. _:b376135859 . . _:b376135858 . . _:b376135869 . . _:b376135868 . _:b376136162 . _:b376136291 . _:b376135871 . _:b376135870 . _:b376136237 . _:b376135865 . _:b3471514 "It is also known that some surface adhesins, such as protein A and fibronectin-binding protein, are cleaved by the native S. aureus secreted proteases [>>43<<],[44]. Considering the agr system regulates the secreted proteases [45],[46], we hypothesized that increased expression of extracellular proteases could be responsible for biofilm detachment." . . _:b376135864 . _:b376135867 . . _:b376135866 . _:b376135291 . . _:b376135811 . _:b376135877 . _:b3471571 . . . . _:b3471465 . _:b376135218 . _:b376135876 . _:b376135910 . . _:b376135879 . _:b376135878 . _:b376135873 . . _:b376135872 . _:b376135875 . . _:b376135874 . . . _:b376135885 . _:b376135884 . _:b3471472 . _:b376135887 . _:b376136272 . . _:b376136140 . . _:b376135886 . _:b376135881 . _:b376135880 . _:b376136021 . . _:b376135883 . _:b376136650 . . _:b376135325 . _:b376135212 . _:b3471465 "[85] SH1000 rsbU positive derivative of 8325-4, agr Type INone [89] SH1001SH1000/\u0394agr::tet Tet [89] FRI1169 agr Type INone [31] SA502A agr Type IINone [15] ATCC25923 agr Type IIINoneATCCKB600\u0394spl::erm Erm [90] SP6391 sspA::erm Erm [>>50<<] DU1126 sspA::tet Tet [91] MN8\u0394ica::tet Tet [92] AH462SH1000/pDB59Cam [16] AH500SH1000/pAH9ErmThis workAH595SH1000/\u0394ica:" . . _:b376135882 . . _:b376135893 . _:b376135892 . _:b376136788 . . . . _:b376135895 . _:b376136297 . _:b376135894 . _:b376136240 . _:b376135889 . _:b376136120 . _:b376135888 . _:b376135496 . _:b3471570 . _:b376135891 . . _:b376135548 . _:b376135890 . _:b376136661 . _:b376135901 . _:b376135900 . . _:b3471537 "on biofilm detachment have focused on factors capable of initiating the process, such as nutrient availability [54],[55], nitric oxide exposure [56], oxygen tension [57], iron salts [58], chelators [59], and signaling molecules [>>60<<]\u2013[63]. Alternatively, detachment studies have addressed effector gene products that contribute to the dissolution of the biofilm, including surfactants [10],[13],[64],[65], hydrolases [66],[67], proteases [37]\u2013[39], and DNase [68]." . _:b376135903 . _:b376136807 . . _:b376135902 . _:b376135668 . _:b376135897 . . _:b376135896 . _:b376136022 . _:b376136037 . _:b376135899 . _:b376135566 . . _:b376135898 . . _:b376135909 . _:b376135908 . . _:b3471524 "Aur is a metalloprotease that is required to initiate a zymogen activation cascade [>>49<<],[50], starting with the V8 protease [51], which in turn activates the SspB cysteine protease [52]." . . _:b376135911 . _:b376135910 . . . . _:b376135905 . . _:b376135904 . . . _:b376135907 . _:b376135906 . _:b376136760 . _:b376135430 . _:b376135217 . _:b376135917 . _:b376135842 . _:b376135916 . _:b376135919 . . _:b376135918 . . . _:b376135355 . _:b376135913 . _:b376136741 . _:b376135912 . _:b376135912 . _:b376135257 . . _:b376135915 . . _:b376136211 . _:b376135746 . _:b376135439 . _:b376135914 . . _:b376136824 . _:b376135925 . _:b376136767 . . _:b376135924 . . _:b376135774 . _:b376135576 . _:b376135927 . _:b3471490 "The activating signals of each group cross-inhibits the alternative signal receptors with surprising potency, a phenomenon termed \u201Cbacterial interference\u201D [>>15<<]. Since AIP-I and AIP-IV differ by only one amino acid and function interchangeably [28], they are grouped together in the classification scheme, although this assignment has been controversial [29],[30]." . . _:b376136001 . . _:b376135926 . _:b376135921 . _:b376135486 . . _:b376136853 . _:b376136435 . _:b376135920 . _:b376136207 . _:b376135923 . _:b376136411 . _:b376135922 . _:b376135933 . . _:b376135932 . . _:b376135935 . _:b376135511 . . _:b376135934 . _:b376136062 . _:b376135572 . _:b376135929 . . . . _:b376135284 . _:b376135748 . _:b376135928 . _:b376135931 . . _:b376135645 . _:b376135930 . _:b376136402 . . . . . _:b376136577 . _:b3471538 "on biofilm detachment have focused on factors capable of initiating the process, such as nutrient availability [54],[55], nitric oxide exposure [56], oxygen tension [57], iron salts [58], chelators [59], and signaling molecules [60]\u2013[>>63<<]. Alternatively, detachment studies have addressed effector gene products that contribute to the dissolution of the biofilm, including surfactants [10],[13],[64],[65], hydrolases [66],[67], proteases [37]\u2013[39], and DNase [68]." . . . . _:b376136504 . _:b3471513 . . _:b376136548 . . _:b376136380 . _:b376135555 . . _:b376135618 . . . _:b376135728 . _:b3471512 . _:b376136019 . _:b3471525 . _:b376136026 . _:b376136733 . . . . . . . _:b3471459 "coli DH5\u03B1-ECloning strainNoneInvitrogenAH394ER2566/\u0394gshA::cat Cam [27] AH426AH394/pDnaB8\u2013AIPIAmp [27] AH495AH394/pDnaB8\u2013AIPIIAmp [27] AH496AH394/pDnaB8\u2013AIPIIIAmp [27] Staphylococcus aureus RN4220Restriction mutant of 8325-4None [>>85<<] SH1000 rsbU positive derivative of 8325-4, agr Type INone [89] SH1001SH1000/\u0394agr:" . . . _:b376136551 . _:b376135983 . _:b376136338 . _:b376136298 . _:b376136846 . _:b376136514 . _:b376136238 . . . . . _:b376135783 . _:b376136301 . _:b376135954 . _:b376135745 . . . . _:b376136546 . _:b376136109 . . . . _:b376135651 . . _:b376136805 . _:b376135409 . _:b3471588 . _:b376135673 . . _:b376135418 . _:b376136335 . . . . . . _:b376135805 . . _:b3471463 "[27] Staphylococcus aureus RN4220Restriction mutant of 8325-4None [85] SH1000 rsbU positive derivative of 8325-4, agr Type INone [89] SH1001SH1000/\u0394agr::tet Tet [89] FRI1169 agr Type INone [31] SA502A agr Type IINone [>>15<<] ATCC25923 agr Type IIINoneATCCKB600\u0394spl::erm Erm [90] SP6391 sspA::erm Erm [50] DU1126 sspA:" . . _:b376135830 . _:b376136117 . . _:b376136496 . . . . _:b3471451 "it binds to a surface histidine kinase receptor, initiating a regulatory cascade that controls expression of a myriad of virulence factors, such as proteases, hemolysins, and toxins [18]. A recent study by Yarwood et. al. [>>19<<] raised the possibility that the agr quorum-sensing system is involved in biofilm detachment." . _:b3471526 "Aur is a metalloprotease that is required to initiate a zymogen activation cascade [49],[50], starting with the V8 protease [>>51<<], which in turn activates the SspB cysteine protease [52]." . _:b376135408 . . _:b3471497 "The strains tested were (i) FRI1169, agr-I, toxic shock syndrome isolate [31]; (ii) SA502a (ATCC27217), nasal isolate and prototype agr-II strain [15],[32]; and (iii) ATCC25923, clinical agr-III isolate [>>9<<]. When the correct AIP signal was added to 2-day old biofilms of each strain (FRI1169, AIP-1; SA502a, AIP-II; ATCC25923, AIP-III), signal addition resulted in robust detachment of each biofilm over a period of 48 hours (Figure 3). These" . . _:b376135740 . . . _:b376136552 . _:b376135907 . _:b376136266 . . _:b376135328 . . . . _:b376135417 . . _:b3471462 . _:b376135380 . _:b3471550 "These results are in accord with previous studies showing that agr mutants have a propensity to form biofilms [13],[14] and that cells actively expressing agr leave biofilms at a high frequency [>>19<<]. Our findings also explain why S. aureus biofilm formation requires glucose supplementation to growth media." . . . _:b376136565 . . _:b376135837 . . . _:b376136626 . . . _:b376136647 . _:b376136186 . _:b376136275 . _:b376135392 . _:b376135264 . . _:b3471560 . _:b376136501 . _:b376136696 . _:b376136475 . _:b376135517 . _:b376135425 . _:b376135210 . . . _:b376136849 . _:b3471502 "Similar to previous antibiotic susceptibility results [>>19<<], even at the highest concentration tested (100 \u00B5g/ml), the level of rifampicin killing was <2 log units of the biofilm biomass (Figure 6)." . . _:b376135294 . _:b376136410 . _:b376135940 . . . _:b376136511 . . _:b376136264 . . . _:b3471539 . . _:b376135867 . . . . _:b376136793 . . . _:b3471576 "Also, the S. aureus secreted proteases are known to activate lipase (Sal-1 and Sal-2) precursors [>>75<<] and process other secreted enzymes, such as staphylococcal nuclease [76],[77]." . _:b376136073 . . _:b376135482 . _:b376135527 . . _:b376135220 . _:b376135884 . _:b376135814 . _:b376135656 . _:b376136003 . _:b376136093 . _:b376135920 . _:b376135229 . . . . _:b3471577 "Also, the S. aureus secreted proteases are known to activate lipase (Sal-1 and Sal-2) precursors [75] and process other secreted enzymes, such as staphylococcal nuclease [>>76<<],[77]." . _:b376135968 . _:b3471441 "challenge presented by biofilm infections is the remarkable resistance to both host immune responses and available chemotherapies [6],[7], and estimates suggest that as many as 80% of chronic bacterial infections are biofilm associated [>>8<<]. In response to certain environmental cues, bacteria living in biofilms are capable of using active mechanisms to leave biofilms and return to the planktonic (free-living) state in which sensitivity to antimicrobials is regained [9]\u2013[11]." . _:b376136031 . . . _:b3471541 "Alternatively, detachment studies have addressed effector gene products that contribute to the dissolution of the biofilm, including surfactants [10],[13],[>>64<<],[65], hydrolases [66],[67], proteases [37]\u2013[39], and DNase [68]." . . _:b376136155 . . . . . . . _:b376135543 . _:b376135833 . . _:b376135881 . _:b376135753 . _:b376136605 . _:b3471585 . _:b376136386 . _:b376135777 . _:b376136601 . _:b3471586 "Quorum-sensing has been implicated in dispersal of biofilms formed by Yersinia pseudotuberculosis [79], Rhodobacter sphaeroides [80], Pseudomonas aureofaciens [>>81<<], Xanthomonas capmestris [62], and Serratia marceascens [61]." . . _:b376136632 . . _:b376135882 . . . . _:b376135698 . _:b376135943 . _:b376136061 . . . . . . _:b376136277 . _:b376135477 . . . _:b376135667 . . . _:b376136045 . . _:b376136329 . . . . . _:b376136231 . _:b3471516 "Considering the agr system regulates the secreted proteases [>>45<<],[46], we hypothesized that increased expression of extracellular proteases could be responsible for biofilm detachment." . _:b376136391 . _:b376135659 . . _:b376135258 . _:b376135807 . _:b376135934 . . . . . _:b3471539 "Alternatively, detachment studies have addressed effector gene products that contribute to the dissolution of the biofilm, including surfactants [>>10<<],[13],[64],[65], hydrolases [66],[67], proteases [37]\u2013[39], and DNase [68]." . . . . _:b3471529 "Considering the Spl proteases are not zymogens [>>53<<], we examined the combined effects of the Aur cascade and the Spl proteases by constructing an \u0394aur \u0394spl:" . . _:b376136197 "2"^^ . . . _:b376135320 . _:b376136196 "2"^^ . _:b3471585 "Quorum-sensing has been implicated in dispersal of biofilms formed by Yersinia pseudotuberculosis [79], Rhodobacter sphaeroides [>>80<<], Pseudomonas aureofaciens [81], Xanthomonas capmestris [62], and Serratia marceascens [61]." . _:b376136199 "2"^^ . _:b376135312 . . _:b376136198 "2"^^ . _:b376136123 . . _:b376136193 "2"^^ . . _:b376136192 "2"^^ . _:b376135443 . _:b3471574 "Atl is additionally known to require proteolytic processing for activation, and this processing is PMSF inhibited [>>74<<]. Other possibilities include microbial surface components recognizing adhesive matrix molecules (MSCRAMMs), which are important for adherence to the extracellular matrices of mammalian cells [40]. Also, the S. aureus secreted proteases" . . _:b376135693 . _:b376136195 "2"^^ . _:b376135251 . _:b376135733 . _:b376135813 . _:b376136593 . _:b376136194 "2"^^ . . _:b376136205 "2"^^ . . _:b376136458 . _:b376136040 . _:b376136204 "2"^^ . _:b3471562 "S. aureus has been reported to form biofilms through an ica-dependent mechanism suggesting that PIA could have a role in detachment [34],[>>36<<]. We observed no defect in microtiter or flow cell biofilm formation using an ica mutant of SH1000 (Figure 7)." . . _:b376136207 "2"^^ . _:b376135647 . _:b376136206 "2"^^ . _:b376135607 . _:b376136201 "2"^^ . . _:b376135951 . _:b376136200 "2"^^ . . _:b376136560 . _:b376136203 "2"^^ . _:b376135747 . _:b376135847 . . . _:b376136202 "2"^^ . _:b376135262 . _:b376136213 "2"^^ . . . _:b376136212 "2"^^ . _:b3471584 "Quorum-sensing has been implicated in dispersal of biofilms formed by Yersinia pseudotuberculosis [>>79<<], Rhodobacter sphaeroides [80], Pseudomonas aureofaciens [81], Xanthomonas capmestris [62], and Serratia marceascens [61]." . _:b376136215 "2"^^ . _:b376136224 . _:b376136214 "2"^^ . _:b376136209 "2"^^ . _:b376136809 . . _:b376136208 "2"^^ . . . _:b376136211 "2"^^ . _:b376136210 "2"^^ . . _:b376136221 "2"^^ . . . _:b376136538 . . _:b376136232 . _:b376136220 "2"^^ . . . _:b376136053 . _:b376136223 "2"^^ . _:b376136222 "2"^^ . _:b376136217 "2"^^ . . _:b376136216 "2"^^ . . _:b376136219 "2"^^ . . _:b376136728 . . _:b376136218 "2"^^ . . _:b376136528 . _:b376136229 "2"^^ . . _:b376136515 . _:b376136228 "2"^^ . _:b376136231 "2"^^ . . _:b376136230 "2"^^ . _:b376135364 . _:b376136225 "2"^^ . . . _:b376136224 "2"^^ . _:b376135821 . _:b376136107 . . _:b376136227 "2"^^ . _:b376135268 . _:b376136226 "2"^^ . . _:b376136237 "2"^^ . _:b376136251 . . . _:b376135361 . _:b376136452 . _:b376136236 "2"^^ . . _:b376136239 "2"^^ . _:b376136323 . . . _:b376136238 "2"^^ . . _:b376136248 . _:b376135750 . _:b376136233 "2"^^ . _:b376136232 "2"^^ . . . _:b376136235 "2"^^ . _:b376136038 . _:b376136234 "2"^^ . _:b376136245 "2"^^ . . _:b376136244 "2"^^ . . . _:b3471549 . _:b376136247 "2"^^ . _:b3471518 . _:b376136246 "2"^^ . _:b376136241 "2"^^ . _:b376136459 . _:b376135859 . _:b376135932 . _:b376135991 . . _:b376136240 "2"^^ . _:b376136641 . . . . _:b3471468 "Tet [89] FRI1169 agr Type INone [31] SA502A agr Type IINone [15] ATCC25923 agr Type IIINoneATCCKB600\u0394spl::erm Erm [90] SP6391 sspA::erm Erm [50] DU1126 sspA::tet Tet [91] MN8\u0394ica::tet Tet [92] AH462SH1000/pDB59Cam [>>16<<] AH500SH1000/pAH9ErmThis workAH595SH1000/\u0394ica::tet TetThis workAH596SH1000/pDB59+pAH9Cam, ErmThis workAH703SH1000/\u0394aur NoneThis workAH741SH1000/sspA:" . _:b376136243 "2"^^ . . . . _:b376136242 "2"^^ . _:b3471455 "Plasmid DNA was prepared from E. coli and transformed by electroporation into S. aureus RN4220 as described [>>84<<]. Plasmids were moved from RN4220 into other S. aureus strains by transduction with bacteriophage \u03B180 [85] or by purifying the plasmid DNA and transformed by electroporation into appropriate strains. To move sspA and splABCDEF mutations" . _:b376135256 . _:b376136253 "2"^^ . . _:b376136252 "2"^^ . . _:b376136313 . _:b376136202 . . _:b376136255 "2"^^ . _:b376136254 "2"^^ . _:b376136308 . _:b376136249 "2"^^ . _:b376136375 . . _:b376136248 "2"^^ . . _:b376136177 . _:b376136251 "2"^^ . . _:b376136250 "2"^^ . . _:b376135606 . _:b376136261 "2"^^ . . _:b376136260 "2"^^ . . _:b376136263 "2"^^ . _:b376135947 . . _:b376136262 "2"^^ . _:b376136537 . _:b376136257 "2"^^ . . _:b376135945 . _:b376136256 "2"^^ . _:b376136259 "2"^^ . _:b376136258 "2"^^ . _:b376135265 . _:b376136269 "2"^^ . _:b376136218 . . _:b376136268 "2"^^ . _:b376135917 . . _:b376136271 "2"^^ . _:b376136721 . _:b376136270 "2"^^ . . . . _:b376136265 "2"^^ . _:b376136264 "2"^^ . . . _:b376136267 "2"^^ . _:b376136558 . . _:b376136243 . . _:b376136692 . . _:b376136266 "2"^^ . . _:b376136277 "2"^^ . _:b376136494 . _:b3471510 "In S. aureus strains that produce ica-independent biofilms, proteinase K eliminates adherence and biofilm formation [35], [37]\u2013[>>39<<], perhaps through cleavage of surface structures." . _:b376135941 . _:b376136276 "2"^^ . . _:b376136279 "2"^^ . _:b376136278 "2"^^ . . _:b376136273 "2"^^ . _:b376136526 . . _:b376136272 "2"^^ . _:b3471439 "The opportunistic pathogen Staphylococcus aureus can form biofilms on many host tissues and implanted medical devices often causing chronic infections [>>2<<]\u2013[5]. The challenge presented by biofilm infections is the remarkable resistance to both host immune responses and available chemotherapies [6],[7], and estimates suggest that as many as 80% of chronic bacterial infections are biofilm" . _:b376136275 "2"^^ . _:b376136530 . _:b376136274 "2"^^ . . _:b376136138 . _:b376136285 "2"^^ . _:b376135493 . _:b376135939 . . _:b376136284 "2"^^ . . . _:b376136287 "2"^^ . . _:b376136286 "2"^^ . . _:b376136281 "2"^^ . _:b3471529 . _:b376136280 "2"^^ . _:b376136283 "2"^^ . _:b376135593 . _:b376136282 "2"^^ . _:b376136293 "2"^^ . _:b376135241 . _:b376136292 "2"^^ . . . _:b376136295 "2"^^ . _:b376136596 . . _:b376136294 "2"^^ . . _:b3471535 "The majority of studies on biofilm detachment have focused on factors capable of initiating the process, such as nutrient availability [54],[55], nitric oxide exposure [56], oxygen tension [57], iron salts [>>58<<], chelators [59], and signaling molecules [60]\u2013[63]." . _:b376136289 "2"^^ . _:b376135385 . _:b376136288 "2"^^ . _:b376135975 . _:b376136291 "2"^^ . . _:b376136290 "2"^^ . _:b376136444 . . . _:b376136301 "2"^^ . _:b376136401 . _:b376136300 "2"^^ . _:b376135505 . . _:b376135672 . . . . _:b376136303 "2"^^ . . _:b376135855 . _:b376136302 "2"^^ . . _:b376135492 . _:b376136297 "2"^^ . _:b376136296 "2"^^ . . _:b376136299 "2"^^ . . _:b376136298 "2"^^ . . _:b376136309 "2"^^ . _:b376136308 "2"^^ . _:b3471583 . _:b376136311 "2"^^ . _:b376136310 "2"^^ . _:b376135674 . . _:b376136549 . _:b376135997 . . _:b376136305 "2"^^ . _:b376136304 "2"^^ . . _:b376136668 . . _:b376136307 "2"^^ . _:b376136306 "2"^^ . _:b376135687 . . . _:b376136317 "2"^^ . _:b376136316 "2"^^ . _:b376136129 . _:b376136685 . _:b376136319 "2"^^ . _:b376136206 . _:b376135680 . . _:b376136318 "2"^^ . . _:b376136313 "2"^^ . _:b376135344 . _:b376136312 "2"^^ . . . _:b376136315 "2"^^ . _:b376136314 "2"^^ . _:b376135653 . . _:b376136325 "2"^^ . _:b376136098 . _:b376136381 . _:b376136324 "2"^^ . _:b376136852 . _:b376136327 "2"^^ . _:b376136326 "2"^^ . _:b376136075 . _:b376136477 . _:b376135894 . _:b376136321 "2"^^ . . _:b376135401 . _:b376135718 . _:b376136320 "2"^^ . _:b376136367 . _:b376136184 . _:b376136323 "2"^^ . _:b376135404 . _:b376136322 "2"^^ . _:b376135389 . . _:b376136333 "2"^^ . . _:b3471550 . _:b376136332 "2"^^ . _:b376136110 . . . _:b376136335 "2"^^ . _:b376136334 "2"^^ . _:b376136329 "2"^^ . . _:b376136328 "2"^^ . _:b376136331 "2"^^ . _:b376136330 "2"^^ . . . . _:b376136341 "2"^^ . . . _:b376136340 "2"^^ . . _:b376136343 "2"^^ . _:b376136342 "2"^^ . _:b376136337 "2"^^ . _:b376136336 "2"^^ . _:b3471563 "PIA is not a major matrix component of S. aureus biofilms, as exogenous addition of dispersin B, an N-acetyl-glucosaminidase capable of degrading PIA, has little effect on established biofilms of SH1000 and other S. aureus strains [>>70<<]. In contrast, dispersin B does detach S. epidermidis biofilms indicating a more significant role for PIA in the S. epidermidis matrix structure [70]." . _:b376136487 . _:b376136527 . _:b376136339 "2"^^ . _:b3471575 . _:b376136338 "2"^^ . _:b376136349 "2"^^ . _:b376135700 . _:b376136348 "2"^^ . _:b376136351 "2"^^ . _:b376135433 . _:b376136350 "2"^^ . _:b376136345 "2"^^ . _:b3471500 "This biofilm mediated resistance hinders treatment of many chronic S. aureus biofilm related infections, including endocarditis, osteomyelitis, and indwelling medical device infections [>>3<<],[33]. Therefore, we asked whether AIP-dispersed bacteria regained sensitivity to a clinically relevant antibiotic, rifampicin. To test this, we collected detached cells from an AIP-treated biofilm effluent and compared resistance to" . _:b376136103 . _:b376136169 . _:b376136344 "2"^^ . _:b376135795 . . _:b376136347 "2"^^ . _:b376135196 . _:b376136033 . _:b376136346 "2"^^ . . _:b376136357 "2"^^ . . . _:b376136356 "2"^^ . _:b376136359 "2"^^ . . _:b376136358 "2"^^ . _:b376136353 "2"^^ . _:b376136261 . . _:b376136352 "2"^^ . . _:b376136355 "2"^^ . _:b376135841 . _:b376135610 . . _:b376136354 "2"^^ . . _:b376136365 "2"^^ . _:b376135858 . _:b376136364 "2"^^ . _:b376136539 . _:b376135707 . _:b376136367 "2"^^ . . _:b376136067 . _:b376136366 "2"^^ . _:b376136361 "2"^^ . _:b376136179 . _:b376136212 . _:b376135281 . _:b376136360 "2"^^ . _:b376135568 . _:b376135551 . _:b376136363 "2"^^ . _:b376136379 . _:b376135396 . _:b376136362 "2"^^ . _:b376136373 "2"^^ . _:b376136274 . _:b376136372 "2"^^ . . _:b376135530 . _:b376136375 "2"^^ . _:b376136118 . . _:b376136374 "2"^^ . _:b376136002 . _:b376136369 "2"^^ . . _:b376136187 . _:b376136368 "2"^^ . _:b376136371 "2"^^ . . _:b376136842 . _:b376136370 "2"^^ . _:b376136381 "2"^^ . _:b3471502 . _:b376135931 . _:b376136380 "2"^^ . . _:b376136383 "2"^^ . _:b376136382 "2"^^ . _:b3471499 . _:b376136377 "2"^^ . _:b376136376 "2"^^ . . . _:b376136379 "2"^^ . _:b376136378 "2"^^ . . . . _:b376136389 "2"^^ . . _:b376136388 "2"^^ . _:b376136762 . . . . _:b376135331 . _:b376135203 . _:b376136391 "2"^^ . _:b376136163 . _:b376136390 "2"^^ . _:b376135937 . _:b376136385 "2"^^ . _:b376136384 "2"^^ . . . _:b376136358 . _:b376136387 "2"^^ . . _:b376135639 . _:b376136386 "2"^^ . . _:b376136397 "2"^^ . _:b376135986 . _:b376136396 "2"^^ . . _:b376135717 . _:b376136399 "2"^^ . _:b376136398 "2"^^ . . _:b376136059 . . _:b376136393 "2"^^ . . _:b376136392 "2"^^ . _:b376135626 . . _:b376136395 "2"^^ . _:b376135994 . _:b376136394 "2"^^ . . _:b376136405 "2"^^ . _:b3471464 "mutant of 8325-4None [85] SH1000 rsbU positive derivative of 8325-4, agr Type INone [89] SH1001SH1000/\u0394agr::tet Tet [89] FRI1169 agr Type INone [31] SA502A agr Type IINone [15] ATCC25923 agr Type IIINoneATCCKB600\u0394spl::erm Erm [>>90<<] SP6391 sspA::erm Erm [50] DU1126 sspA::tet Tet [91] MN8\u0394ica::tet Tet [92] AH462SH1000/pDB59Cam [16] AH500SH1000/pAH9ErmThis workAH595SH1000/\u0394ica:" . _:b376136729 . . . _:b376136404 "2"^^ . . . _:b376136407 "2"^^ . _:b376136406 "2"^^ . _:b376136401 "2"^^ . . . . _:b376136400 "2"^^ . _:b376136403 "2"^^ . _:b376136317 . _:b3471511 . _:b376136830 . _:b376135317 . _:b376136402 "2"^^ . _:b376136446 . . . _:b376136413 "2"^^ . _:b376135502 . _:b376136412 "2"^^ . _:b376136063 . _:b376135562 . _:b376135825 . . _:b376136415 "2"^^ . . _:b376135228 . . . _:b376136414 "2"^^ . _:b376135356 . . _:b376136137 . _:b376136409 "2"^^ . . . _:b376136408 "2"^^ . . . _:b376136642 . . _:b376136411 "2"^^ . _:b376136410 "2"^^ . _:b376136421 "2"^^ . . . _:b376136420 "2"^^ . _:b376136036 . . . _:b3471496 "The strains tested were (i) FRI1169, agr-I, toxic shock syndrome isolate [31]; (ii) SA502a (ATCC27217), nasal isolate and prototype agr-II strain [15],[>>32<<]; and (iii) ATCC25923, clinical agr-III isolate [9]." . _:b376136423 "2"^^ . _:b376136422 "2"^^ . . . . _:b376136417 "2"^^ . _:b376135893 . _:b376136663 . _:b376136489 . _:b376136303 . . _:b376136416 "2"^^ . _:b376136419 "2"^^ . . _:b376136418 "2"^^ . _:b3471504 . _:b376136429 "2"^^ . _:b376136428 "2"^^ . . . . _:b376136431 "2"^^ . _:b376135478 . _:b376135193 . _:b376136430 "2"^^ . _:b376136425 "2"^^ . . _:b376136710 . _:b376136424 "2"^^ . _:b376136427 "2"^^ . _:b376136426 "2"^^ . _:b376136437 "2"^^ . _:b376136436 "2"^^ . . _:b376136439 "2"^^ . . . _:b376135749 . _:b376136438 "2"^^ . _:b3471555 . _:b376135959 . _:b376136433 "2"^^ . _:b3471499 "Biofilm growth of S. aureus increases resistance to antimicrobials when compared to the planktonic growth mode [9],[>>19<<]. This biofilm mediated resistance hinders treatment of many chronic S. aureus biofilm related infections, including endocarditis, osteomyelitis, and indwelling medical device infections [3],[33]." . _:b376136589 . _:b376136432 "2"^^ . _:b376136435 "2"^^ . _:b376135377 . _:b3471450 . _:b376135407 . . _:b376136434 "2"^^ . _:b3471443 . _:b3471479 . _:b376136445 "2"^^ . _:b376136309 . _:b376135824 . _:b376136444 "2"^^ . _:b376136447 "2"^^ . _:b3471514 . . _:b376136446 "2"^^ . _:b376136441 "2"^^ . . _:b376136440 "2"^^ . _:b376136443 "2"^^ . . _:b376136229 . _:b376136442 "2"^^ . . . _:b376136453 "2"^^ . . _:b376136452 "2"^^ . . _:b376135885 . _:b376136455 "2"^^ . _:b376136557 . _:b376136454 "2"^^ . . _:b376136223 . _:b376136449 "2"^^ . _:b376136448 "2"^^ . . _:b376136451 "2"^^ . . _:b376136450 "2"^^ . _:b376136550 . . . _:b376136461 "2"^^ . _:b376136460 "2"^^ . _:b3471519 "There are 10 known extracellular proteases produced by most S. aureus strains and expression of all these enzymes is controlled by the agr system [18],[>>45<<],[46]. These 10 proteases include the metalloprotease aureolysin (aur), two cysteine proteases (scpA and sspB), and seven serine proteases (sspA (V8) and splABCDEF) [47]." . _:b376136839 . _:b376136463 "2"^^ . . _:b376136462 "2"^^ . . _:b376136832 . _:b376135649 . _:b376136457 "2"^^ . _:b376136510 . _:b376136456 "2"^^ . . _:b376136561 . _:b376136459 "2"^^ . _:b3471561 . . _:b3471491 "Since AIP-I and AIP-IV differ by only one amino acid and function interchangeably [>>28<<], they are grouped together in the classification scheme, although this assignment has been controversial [29],[30]." . _:b376136458 "2"^^ . _:b376136469 "2"^^ . . . _:b376136468 "2"^^ . _:b376135513 . _:b376135965 . . _:b3471453 . _:b376136471 "2"^^ . _:b3471484 "Interestingly, in most published flow cell biofilm studies, one commonality is the use of growth media containing or supplemented with glucose [9], [19], [21]\u2013[>>24<<]. In our own efforts to grow S. aureus flow cell biofilms, we found a strict dependence on glucose supplementation. For the experimental setup, a once-through, continuous culture system was employed as previously described [19],[25], and S." . _:b376135719 . . . . _:b376136470 "2"^^ . _:b376136465 "2"^^ . _:b376136464 "2"^^ . _:b376136368 . _:b376136467 "2"^^ . . _:b3471446 . . _:b376136466 "2"^^ . _:b376136477 "2"^^ . _:b376136476 "2"^^ . _:b376136217 . _:b376135263 . . _:b376136479 "2"^^ . _:b376135810 . _:b376136478 "2"^^ . . _:b376136473 "2"^^ . _:b376135579 . _:b376136472 "2"^^ . . _:b376136090 . _:b376136475 "2"^^ . _:b376136474 "2"^^ . _:b376135473 . _:b376136485 "2"^^ . . _:b376136484 "2"^^ . _:b376136423 . _:b376136487 "2"^^ . . _:b376136486 "2"^^ . _:b376136709 . _:b376136481 "2"^^ . . _:b376136480 "2"^^ . . _:b376135671 . _:b376136483 "2"^^ . . _:b376136482 "2"^^ . _:b376135237 . _:b376136493 "2"^^ . . . _:b376136035 . _:b376135737 . _:b376136492 "2"^^ . _:b376136495 "2"^^ . . _:b376136494 "2"^^ . _:b376136489 "2"^^ . . . _:b376136488 "2"^^ . . _:b376136471 . _:b376136491 "2"^^ . _:b376136490 "2"^^ . _:b376135338 . _:b376136640 . _:b376136501 "2"^^ . . _:b376136500 "2"^^ . . _:b376136503 "2"^^ . _:b376136502 "2"^^ . _:b376136497 "2"^^ . . _:b376136496 "2"^^ . _:b376136600 . _:b376136135 . _:b376136499 "2"^^ . _:b376136498 "2"^^ . _:b376136667 . . _:b376136509 "2"^^ . . _:b376136621 . _:b376136585 . _:b376136508 "2"^^ . _:b376135536 . _:b376136511 "2"^^ . _:b376136256 . _:b376136510 "2"^^ . . _:b376136505 "2"^^ . _:b376135582 . _:b376135927 . _:b376136504 "2"^^ . _:b376135205 . _:b376136507 "2"^^ . . . _:b376136506 "2"^^ . . . _:b376136517 "2"^^ . . _:b376136516 "2"^^ . . _:b376136519 "2"^^ . _:b376136518 "2"^^ . _:b376135288 . _:b3471475 . . _:b376136513 "2"^^ . _:b376136629 . _:b3471466 "derivative of 8325-4, agr Type INone [89] SH1001SH1000/\u0394agr::tet Tet [89] FRI1169 agr Type INone [31] SA502A agr Type IINone [15] ATCC25923 agr Type IIINoneATCCKB600\u0394spl::erm Erm [90] SP6391 sspA::erm Erm [50] DU1126 sspA::tet Tet [>>91<<] MN8\u0394ica::tet Tet [92] AH462SH1000/pDB59Cam [16] AH500SH1000/pAH9ErmThis workAH595SH1000/\u0394ica:" . _:b376136512 "2"^^ . _:b376136515 "2"^^ . _:b376136514 "2"^^ . . _:b376136525 "2"^^ . _:b376136524 "2"^^ . _:b3471485 . _:b376136527 "2"^^ . _:b3471481 . . _:b376136526 "2"^^ . . _:b376136152 . . _:b376136521 "2"^^ . _:b3471482 . _:b376136520 "2"^^ . _:b376136523 "2"^^ . . _:b376136522 "2"^^ . _:b3471521 "These 10 proteases include the metalloprotease aureolysin (aur), two cysteine proteases (scpA and sspB), and seven serine proteases (sspA (V8) and splABCDEF) [>>47<<]. To elucidate what class(es) of proteases are prevalent in AIP-treated biofilms, the effluent from a detaching biofilm was assayed for protease activity in the presence of protease inhibitors or activating agents. The addition of EGTA, an" . _:b376136525 . _:b376135285 . . _:b376136533 "2"^^ . _:b376136532 "2"^^ . _:b376136535 "2"^^ . _:b3471570 "One potential target is the surface adhesins, and possible candidates include the surface proteins Atl, Bap, and SasG, all of which have reported roles in biofilm formation [>>41<<], [42], [71]\u2013[73]." . _:b376136534 "2"^^ . _:b376136660 . . _:b376136529 "2"^^ . . _:b376136528 "2"^^ . . _:b376136531 "2"^^ . . _:b376136530 "2"^^ . _:b3471471 . . _:b376136541 "2"^^ . . _:b376136540 "2"^^ . _:b3471469 . _:b376136543 "2"^^ . . _:b376136542 "2"^^ . _:b376135190 . _:b376136537 "2"^^ . _:b376135865 . _:b376136536 "2"^^ . _:b3471536 . . _:b376136539 "2"^^ . . _:b376136199 . _:b376136538 "2"^^ . . _:b376136549 "2"^^ . . _:b376135360 . . . _:b376135250 . _:b376136548 "2"^^ . _:b376136675 . _:b376136551 "2"^^ . _:b376136775 . _:b376136550 "2"^^ . _:b376136545 "2"^^ . . _:b376136544 "2"^^ . _:b376135760 . _:b376135980 . _:b376136547 "2"^^ . . _:b376136546 "2"^^ . . _:b376136557 "2"^^ . . _:b376136197 . _:b376136556 "2"^^ . . _:b376136559 "2"^^ . _:b376135849 . _:b376136065 . _:b376136558 "2"^^ . _:b376135201 . _:b3471451 . . _:b376136553 "2"^^ . _:b376135282 . _:b376136552 "2"^^ . _:b376136617 . _:b376136555 "2"^^ . _:b376135789 . _:b376135655 . . _:b376136554 "2"^^ . _:b3471442 . _:b376136565 "2"^^ . . _:b3471495 "The strains tested were (i) FRI1169, agr-I, toxic shock syndrome isolate [31]; (ii) SA502a (ATCC27217), nasal isolate and prototype agr-II strain [>>15<<],[32]; and (iii) ATCC25923, clinical agr-III isolate [9]." . _:b376136564 "2"^^ . _:b376136047 . . _:b376136172 . _:b376136567 "2"^^ . _:b376136387 . . _:b376135270 . _:b376136566 "2"^^ . _:b376135909 . _:b376136561 "2"^^ . _:b376136560 "2"^^ . _:b376136738 . _:b376136563 "2"^^ . . . _:b376136562 "2"^^ . _:b3471457 "To move sspA and splABCDEF mutations into appropriate genetic backgrounds, phage transduction with \u03B180 was used as described [>>85<<]. To construct the \u0394aur mutation, the pKOR1-aur plasmid was used as described [16]. Fluorescence measurements with S. aureus strains containing pDB59 were performed as previously described [27]." . . _:b376136573 "2"^^ . _:b376135787 . _:b376136572 "2"^^ . _:b376135384 . _:b376135871 . _:b376136454 . _:b376136575 "2"^^ . _:b376135913 . . _:b376136574 "2"^^ . _:b376136569 "2"^^ . _:b376136568 "2"^^ . . . _:b376136571 "2"^^ . _:b376136570 "2"^^ . _:b376136581 "2"^^ . _:b3471556 . . . _:b376136580 "2"^^ . _:b376136447 . _:b376136461 . _:b376136583 "2"^^ . _:b376135679 . _:b376136582 "2"^^ . . _:b376135761 . _:b376136577 "2"^^ . . . _:b376136576 "2"^^ . . _:b376136579 "2"^^ . _:b376135731 . _:b3471448 "During growth, AIP is synthesized and secreted through a poorly understood mechanism that requires multiple peptidases [>>16<<],[17]. Once AIP reaches a critical concentration, it binds to a surface histidine kinase receptor, initiating a regulatory cascade that controls expression of a myriad of virulence factors, such as proteases, hemolysins, and toxins [18]. A" . _:b376136695 . _:b376136578 "2"^^ . _:b376135801 . _:b376136589 "2"^^ . _:b376135280 . _:b376136588 "2"^^ . . _:b376136591 "2"^^ . _:b376136314 . . _:b376136590 "2"^^ . . . _:b376136585 "2"^^ . _:b376136258 . _:b376135611 . _:b376136013 . . _:b376136584 "2"^^ . _:b3471467 . _:b376136587 "2"^^ . _:b376136586 "2"^^ . . _:b376135310 . _:b376136597 "2"^^ . _:b376136673 . . _:b376136596 "2"^^ . _:b376135379 . _:b376135763 . . _:b376136599 "2"^^ . _:b376135664 . _:b376136598 "2"^^ . _:b376136089 . _:b376136593 "2"^^ . _:b376136592 "2"^^ . . _:b376136633 . _:b376136595 "2"^^ . _:b376135835 . . _:b3471498 . _:b376136594 "2"^^ . . _:b376136605 "2"^^ . _:b376135863 . _:b376136604 "2"^^ . . _:b376136531 . _:b3471497 . _:b376136607 "2"^^ . _:b376136606 "2"^^ . _:b376136087 . _:b376136601 "2"^^ . _:b3471503 . . _:b376136600 "2"^^ . _:b3471445 "Surprisingly, the opposite is true in S. aureus, as the presence of an active quorum-sensing impedes attachment and development of a biofilm [>>13<<],[14]. The S. aureus quorum-sensing system is encoded by the accessory gene regulator (agr) locus and the communication molecule that it produces and senses is called an autoinducing peptide (AIP), which is an eight-residue peptide with" . _:b376135460 . _:b376136340 . . _:b376136603 "2"^^ . . _:b376136602 "2"^^ . _:b376135703 . . _:b376136613 "2"^^ . _:b376136612 "2"^^ . _:b376135240 . _:b376136615 "2"^^ . _:b376135307 . _:b376136614 "2"^^ . _:b376136609 "2"^^ . . _:b376136608 "2"^^ . _:b376136419 . _:b376136611 "2"^^ . . _:b376136610 "2"^^ . . _:b376136621 "2"^^ . _:b376136620 "2"^^ . _:b376135227 . _:b376136777 . _:b376136623 "2"^^ . . . _:b376136622 "2"^^ . _:b3471507 . _:b376136617 "2"^^ . _:b376135799 . _:b376135708 . _:b376136616 "2"^^ . _:b376135253 . _:b376136485 . _:b376136619 "2"^^ . _:b376135254 . _:b376136360 . _:b376136570 . _:b376135629 . _:b376136618 "2"^^ . . _:b376136133 . . _:b376136629 "2"^^ . . _:b376136280 . _:b376136113 . . _:b376136628 "2"^^ . _:b376135272 . _:b376136631 "2"^^ . . _:b376135996 . _:b376136630 "2"^^ . . _:b376136625 "2"^^ . _:b3471576 . _:b376136624 "2"^^ . _:b376136627 "2"^^ . _:b376136626 "2"^^ . . _:b376135904 . _:b376136408 . _:b376136637 "2"^^ . . . _:b376136636 "2"^^ . . _:b376136639 "2"^^ . . _:b376136638 "2"^^ . _:b376136633 "2"^^ . _:b376135243 . _:b376136659 . _:b376136632 "2"^^ . _:b376135538 . _:b376136635 "2"^^ . . _:b376136634 "2"^^ . . _:b376135315 . _:b3471492 . _:b376135641 . _:b376136645 "2"^^ . _:b376136644 "2"^^ . _:b376136647 "2"^^ . _:b376136646 "2"^^ . _:b376136755 . _:b376136641 "2"^^ . . . _:b376136640 "2"^^ . _:b376136643 "2"^^ . _:b376136642 "2"^^ . _:b376135784 . _:b376136653 "2"^^ . _:b376136652 "2"^^ . _:b376136655 "2"^^ . _:b376135230 . _:b376135602 . _:b376136654 "2"^^ . _:b376136649 "2"^^ . _:b3471589 . _:b376136648 "2"^^ . _:b376136651 "2"^^ . _:b376136650 "2"^^ . _:b376136669 . _:b376136576 . _:b376136661 "2"^^ . . _:b376136660 "2"^^ . _:b376136428 . _:b376136663 "2"^^ . . _:b376135890 . _:b376136662 "2"^^ . . _:b376136657 "2"^^ . _:b376136415 . _:b376136656 "2"^^ . . _:b376136659 "2"^^ . _:b376135906 . _:b376136658 "2"^^ . . _:b376136669 "2"^^ . _:b376136007 . _:b376136668 "2"^^ . _:b376135923 . . _:b376136671 "2"^^ . _:b376136670 "2"^^ . . _:b376136665 "2"^^ . _:b376136664 "2"^^ . _:b376136418 . _:b376136052 . _:b376136667 "2"^^ . _:b3471477 "results" . _:b376136682 . _:b376136666 "2"^^ . _:b376135779 . _:b376136677 "2"^^ . _:b376135587 . . _:b376136676 "2"^^ . . _:b376136679 "2"^^ . . _:b376135509 . _:b376136678 "2"^^ . . _:b376136673 "2"^^ . _:b376136672 "2"^^ . _:b376136675 "2"^^ . _:b3471541 . _:b376136674 "2"^^ . _:b376136685 "2"^^ . _:b376136684 "2"^^ . . . . _:b376136687 "2"^^ . _:b376136686 "2"^^ . . _:b376136681 "2"^^ . _:b376136680 "2"^^ . _:b376136289 . _:b376136307 . . _:b376136683 "2"^^ . _:b376135416 . _:b376136682 "2"^^ . _:b376135332 . . _:b376136445 . _:b376136693 "2"^^ . . _:b376136692 "2"^^ . _:b376136018 . _:b3471464 . _:b376136695 "2"^^ . . _:b376136694 "2"^^ . . _:b376136689 "2"^^ . . _:b376136325 . . . _:b376136688 "2"^^ . . _:b376135296 . _:b376136691 "2"^^ . . _:b376136041 . _:b376136690 "2"^^ . . _:b376136701 "2"^^ . _:b376135347 . _:b376136700 "2"^^ . . _:b376135853 . _:b376136703 "2"^^ . . _:b376136784 . _:b376136702 "2"^^ . _:b376136697 "2"^^ . _:b376136009 . . _:b376136696 "2"^^ . _:b376135556 . . . _:b376136699 "2"^^ . _:b376136698 "2"^^ . _:b3471591 "However, homoserine lactone signals play a divergent role in Pseudomonas aeuruginosa [12], Pseudomonas fluorescens [82], and Burkholderia cepacia [>>83<<], where the active versions of these quorum-sensing systems are necessary for biofilm formation and robustness under some growth conditions." . _:b376135685 "3"^^ . _:b376135684 "3"^^ . . _:b376135687 "3"^^ . _:b376135686 "3"^^ . . _:b376135681 "3"^^ . _:b376135680 "3"^^ . _:b376135683 "3"^^ . . _:b376135682 "3"^^ . _:b376135905 . _:b376136356 . _:b376135693 "3"^^ . . . . _:b376135692 "3"^^ . _:b376135695 "3"^^ . . _:b376135694 "3"^^ . _:b376135689 "3"^^ . _:b376136191 . _:b376136054 . . _:b376135688 "3"^^ . _:b376136837 . _:b376135691 "3"^^ . _:b3471575 "Other possibilities include microbial surface components recognizing adhesive matrix molecules (MSCRAMMs), which are important for adherence to the extracellular matrices of mammalian cells [>>40<<]. Also, the S. aureus secreted proteases are known to activate lipase (Sal-1 and Sal-2) precursors [75] and process other secreted enzymes, such as staphylococcal nuclease [76],[77]." . _:b376135682 . _:b376135690 "3"^^ . _:b376135971 . _:b376135701 "3"^^ . _:b376135510 . . _:b376135700 "3"^^ . . . _:b376135703 "3"^^ . . _:b376135431 . _:b376135702 "3"^^ . _:b376136482 . . . _:b376135697 "3"^^ . . _:b376135550 . _:b376135508 . _:b376135696 "3"^^ . _:b376135699 "3"^^ . . _:b376135698 "3"^^ . . _:b376135189 . . _:b376135709 "3"^^ . . _:b376135349 . . _:b376136149 . _:b376135708 "3"^^ . _:b376135711 "3"^^ . . _:b376135710 "3"^^ . _:b376136845 . _:b376135501 . _:b376135617 . _:b376135705 "3"^^ . _:b376135526 . _:b376135704 "3"^^ . . _:b376135707 "3"^^ . . _:b376136151 . _:b376135706 "3"^^ . _:b376135717 "3"^^ . _:b376135506 . _:b376135716 "3"^^ . _:b376135874 . . _:b376136730 . _:b376135719 "3"^^ . _:b376135718 "3"^^ . _:b376135713 "3"^^ . . _:b376135712 "3"^^ . . . _:b376135715 "3"^^ . _:b376135714 "3"^^ . . _:b376136623 . _:b376135725 "3"^^ . _:b376135724 "3"^^ . _:b376135727 "3"^^ . _:b376135337 . . _:b3471526 . _:b376135580 . _:b376135726 "3"^^ . _:b376135721 "3"^^ . . _:b376135720 "3"^^ . _:b376135723 "3"^^ . . _:b376135722 "3"^^ . . _:b376135733 "3"^^ . . _:b376135732 "3"^^ . _:b376135735 "3"^^ . _:b376136497 . . . _:b376136328 . _:b376135734 "3"^^ . . . . . _:b376135729 "3"^^ . _:b376135339 . _:b376135728 "3"^^ . . _:b376135850 . . _:b3471462 "[27] AH496AH394/pDnaB8\u2013AIPIIIAmp [27] Staphylococcus aureus RN4220Restriction mutant of 8325-4None [85] SH1000 rsbU positive derivative of 8325-4, agr Type INone [89] SH1001SH1000/\u0394agr::tet Tet [89] FRI1169 agr Type INone [>>31<<] SA502A agr Type IINone [15] ATCC25923 agr Type IIINoneATCCKB600\u0394spl::erm Erm [90] SP6391 sspA:" . _:b376135731 "3"^^ . . _:b376135730 "3"^^ . . . _:b376135741 "3"^^ . _:b376136158 . . _:b376135740 "3"^^ . _:b376136806 . . . _:b376135412 . . _:b376135743 "3"^^ . . . _:b376135742 "3"^^ . _:b376136072 . . _:b376135308 . _:b376136725 . _:b376135737 "3"^^ . _:b3471501 "This biofilm mediated resistance hinders treatment of many chronic S. aureus biofilm related infections, including endocarditis, osteomyelitis, and indwelling medical device infections [3],[>>33<<]. Therefore, we asked whether AIP-dispersed bacteria regained sensitivity to a clinically relevant antibiotic, rifampicin. To test this, we collected detached cells from an AIP-treated biofilm effluent and compared resistance to intact" . . _:b376135650 . _:b376135736 "3"^^ . . . . _:b376135739 "3"^^ . . _:b3471573 "One potential target is the surface adhesins, and possible candidates include the surface proteins Atl, Bap, and SasG, all of which have reported roles in biofilm formation [41], [42], [71]\u2013[>>73<<]. Atl is additionally known to require proteolytic processing for activation, and this processing is PMSF inhibited [74]. Other possibilities include microbial surface components recognizing adhesive matrix molecules (MSCRAMMs), which are" . _:b376135738 "3"^^ . . _:b376135749 "3"^^ . _:b376135973 . _:b376135748 "3"^^ . . . _:b376135751 "3"^^ . . _:b376135750 "3"^^ . . . _:b376135745 "3"^^ . _:b376135744 "3"^^ . _:b3471525 "Aur is a metalloprotease that is required to initiate a zymogen activation cascade [49],[>>50<<], starting with the V8 protease [51], which in turn activates the SspB cysteine protease [52]." . _:b376136393 . _:b376135747 "3"^^ . . _:b376135746 "3"^^ . _:b376135757 "3"^^ . _:b376135351 . _:b376135756 "3"^^ . . _:b376135759 "3"^^ . . _:b376135758 "3"^^ . . _:b376135753 "3"^^ . . _:b376136836 . . _:b376135752 "3"^^ . . _:b376135755 "3"^^ . _:b376136010 . _:b376135754 "3"^^ . . _:b376136294 . _:b376135765 "3"^^ . . _:b376135764 "3"^^ . _:b376135754 . _:b376135816 . _:b376135767 "3"^^ . _:b376136101 . _:b376135766 "3"^^ . _:b3471552 . . _:b376135761 "3"^^ . . _:b3471461 "[27] AH495AH394/pDnaB8\u2013AIPIIAmp [27] AH496AH394/pDnaB8\u2013AIPIIIAmp [27] Staphylococcus aureus RN4220Restriction mutant of 8325-4None [85] SH1000 rsbU positive derivative of 8325-4, agr Type INone [89] SH1001SH1000/\u0394agr::tet Tet [>>89<<] FRI1169 agr Type INone [31] SA502A agr Type IINone [15] ATCC25923 agr Type IIINoneATCCKB600\u0394spl:" . _:b376135760 "3"^^ . _:b3471554 . _:b376135763 "3"^^ . . _:b376135376 . _:b376135762 "3"^^ . _:b376135596 . . _:b376135773 "3"^^ . _:b376135897 . . _:b376136276 . _:b376135772 "3"^^ . . _:b376135775 "3"^^ . _:b376135681 . _:b376135924 . _:b376136747 . _:b376135774 "3"^^ . _:b3471444 . _:b376135769 "3"^^ . _:b376135768 "3"^^ . . _:b376135771 "3"^^ . _:b376135318 . _:b376135992 . _:b376135770 "3"^^ . . _:b376135995 . _:b376135464 . _:b376135781 "3"^^ . . _:b376135780 "3"^^ . _:b376135783 "3"^^ . _:b376135782 "3"^^ . . _:b376135777 "3"^^ . _:b376135776 "3"^^ . _:b376136346 . _:b376135779 "3"^^ . _:b376136441 . _:b376135273 . _:b376135778 "3"^^ . _:b3471511 "S. aureus is coated with cell wall attached proteins that mediate adherence to a variety of substrates [>>40<<], and some of these adhesins, such as biofilm associated protein (BAP) and SasG are important for biofilm formation [41],[42]." . . _:b376135789 "3"^^ . . . _:b376136260 . _:b376135788 "3"^^ . . _:b3471467 "agr Type INone [89] SH1001SH1000/\u0394agr::tet Tet [89] FRI1169 agr Type INone [31] SA502A agr Type IINone [15] ATCC25923 agr Type IIINoneATCCKB600\u0394spl::erm Erm [90] SP6391 sspA::erm Erm [50] DU1126 sspA::tet Tet [91] MN8\u0394ica::tet Tet [>>92<<] AH462SH1000/pDB59Cam [16] AH500SH1000/pAH9ErmThis workAH595SH1000/\u0394ica::tet TetThis workAH596SH1000/pDB59+pAH9Cam, ErmThis workAH703SH1000/\u0394aur NoneThis workAH741SH1000/sspA:" . . _:b376136737 . _:b376135791 "3"^^ . . . _:b376135790 "3"^^ . . _:b376135785 "3"^^ . . _:b376135784 "3"^^ . _:b376136304 . _:b376135787 "3"^^ . . . _:b376135942 . _:b376135786 "3"^^ . _:b376135797 "3"^^ . _:b376136023 . _:b376135796 "3"^^ . . . _:b376135799 "3"^^ . . _:b376136220 . . _:b376135798 "3"^^ . . . _:b376135793 "3"^^ . _:b376135792 . _:b376136281 . _:b376135792 "3"^^ . . _:b3471460 "Cam [27] AH426AH394/pDnaB8\u2013AIPIAmp [27] AH495AH394/pDnaB8\u2013AIPIIAmp [27] AH496AH394/pDnaB8\u2013AIPIIIAmp [27] Staphylococcus aureus RN4220Restriction mutant of 8325-4None [85] SH1000 rsbU positive derivative of 8325-4, agr Type INone [>>89<<] SH1001SH1000/\u0394agr::tet Tet [89] FRI1169 agr Type INone [31] SA502A agr Type IINone [15] ATCC25923 agr Type IIINoneATCCKB600\u0394spl:" . _:b376135795 "3"^^ . _:b376136453 . _:b376136359 . . _:b376135196 . _:b376135197 . _:b376135794 "3"^^ . . _:b376136239 . _:b376135198 . _:b376135199 . _:b376135192 . _:b376135193 . _:b376135805 "3"^^ . . _:b376135194 . _:b376135195 . _:b376135188 . _:b376135189 . _:b376135804 "3"^^ . _:b376135190 . _:b376135191 . . _:b376135807 "3"^^ . . _:b376136678 . . _:b376135212 . _:b3471458 "To construct the \u0394aur mutation, the pKOR1-aur plasmid was used as described [>>16<<]. Fluorescence measurements with S. aureus strains containing pDB59 were performed as previously described [27]." . _:b376135213 . _:b376135806 "3"^^ . _:b376135214 . _:b376135215 . _:b376135208 . _:b376135209 . _:b376135801 "3"^^ . _:b376135210 . _:b3471523 . _:b376135211 . _:b376135640 . _:b376135713 . _:b376135204 . _:b376135205 . _:b376136185 . _:b376135800 "3"^^ . _:b376135206 . _:b376135207 . _:b376135200 . _:b376135201 . _:b376135803 "3"^^ . _:b376135202 . _:b376135203 . _:b376135228 . _:b376135229 . _:b376135802 "3"^^ . . _:b376135230 . _:b376135231 . _:b376135224 . _:b376135225 . _:b376135813 "3"^^ . . _:b376135226 . _:b376135227 . _:b376135220 . _:b376135221 . _:b376135812 "3"^^ . _:b376135222 . _:b376135223 . _:b376135216 . . _:b376135217 . _:b376135815 "3"^^ . _:b376135326 . _:b376135218 . _:b376135200 . . _:b376135219 . _:b376135244 . _:b376135245 . _:b376135814 "3"^^ . _:b376135246 . _:b376135192 . _:b376135247 . _:b376135240 . _:b376135241 . _:b376135809 "3"^^ . . _:b376135242 . _:b376135243 . _:b376135236 . _:b376135237 . _:b376135808 "3"^^ . _:b376135238 . . _:b376135239 . _:b376135232 . _:b376135233 . _:b376135811 "3"^^ . . _:b376135234 . . _:b376135235 . _:b376135260 . _:b376135261 . _:b376135810 "3"^^ . _:b376135557 . _:b376135262 . _:b376135263 . _:b376135256 . _:b376135257 . _:b376135821 "3"^^ . _:b376135258 . _:b376135259 . _:b376135252 . _:b376135253 . _:b376135820 "3"^^ . _:b376135254 . _:b376135255 . _:b376135248 . . _:b376135823 "3"^^ . _:b376135249 . _:b376135250 . _:b376135251 . _:b376135276 . _:b376135277 . _:b376135822 "3"^^ . _:b376135278 . _:b376135279 . _:b376135272 . _:b376135273 . _:b376136422 . _:b376136188 . . _:b376135817 "3"^^ . _:b376135274 . . _:b376135275 . _:b376135268 . _:b376135269 . _:b376135816 "3"^^ . _:b376135518 . _:b376135270 . _:b376135271 . _:b376135264 . . _:b376135819 "3"^^ . _:b376135265 . _:b376135514 . _:b376135266 . . _:b376135255 . _:b376135267 . _:b376135292 . _:b376135293 . _:b376135818 "3"^^ . _:b376135294 . . . _:b376135295 . _:b376135288 . _:b376135289 . _:b376136233 . _:b376135829 "3"^^ . _:b376135290 . _:b376135291 . _:b376135293 . _:b376135284 . _:b376135285 . _:b376135828 "3"^^ . _:b376135286 . . _:b376135287 . "10.1371%2Fjournal.ppat.1000052" . _:b376135280 . _:b376135281 . _:b376135831 "3"^^ . _:b376135282 . . _:b376135762 . _:b376135283 . _:b376135308 . _:b376135309 . _:b3471488 . _:b376135830 "3"^^ . _:b376135310 . _:b376135311 . _:b376135304 . . _:b376135305 . _:b376135825 "3"^^ . _:b376135766 . _:b376135306 . _:b376135307 . . _:b376135300 . _:b376135301 . _:b376135824 "3"^^ . _:b376135302 . _:b376135303 . _:b376135296 . _:b376135297 . _:b376135827 "3"^^ . _:b376135298 . _:b376135299 . . _:b376135324 . _:b376135341 . _:b376135325 . _:b376135826 "3"^^ . _:b376135326 . _:b376135327 . _:b376135320 . _:b376135321 . _:b376135837 "3"^^ . _:b376135322 . _:b376136516 . _:b376135323 . _:b376135316 . _:b376136282 . _:b376135317 . _:b376135836 "3"^^ . _:b376135318 . _:b376135319 . . _:b376135312 . _:b376135313 . _:b376136427 . _:b376136334 . _:b376135839 "3"^^ . _:b376135314 . _:b376135315 . _:b376135340 . _:b3471480 "Regassa et al. reported that growth on rich media containing glucose represses the agr system through the nonmaintained generation of low pH [>>20<<]. Interestingly, in most published flow cell biofilm studies, one commonality is the use of growth media containing or supplemented with glucose [9], [19], [21]\u2013[24]. In our own efforts to grow S. aureus flow cell biofilms, we found a" . _:b376135341 . _:b376136287 . _:b376135838 "3"^^ . _:b376135342 . _:b376135343 . . _:b376135456 . _:b376135336 . _:b376135337 . _:b376135833 "3"^^ . . _:b376135338 . _:b376135339 . _:b376135411 . _:b376135332 . . _:b376136810 . _:b376135832 "3"^^ . _:b376135333 . . _:b376135334 . _:b376135335 . _:b376136273 . . _:b376135328 . _:b376135329 . _:b376135835 "3"^^ . _:b376135330 . . _:b376135331 . _:b376135356 . _:b376135357 . _:b376135834 "3"^^ . _:b376135358 . _:b376135359 . _:b376135352 . _:b376135353 . _:b376135845 "3"^^ . . _:b376135354 . _:b376135355 . _:b376136388 . _:b376135348 . _:b376135794 . _:b376135844 "3"^^ . . _:b376135349 . _:b376135350 . . _:b376135832 . _:b376135351 . _:b376135344 . _:b376135345 . _:b376135847 "3"^^ . _:b376135346 . _:b376135347 . _:b376135372 . _:b3471543 . _:b376135373 . _:b376135846 "3"^^ . . _:b376135374 . _:b376135375 . _:b376135368 . _:b376135369 . _:b376135841 "3"^^ . _:b376135370 . _:b376135962 . _:b376135371 . _:b376135364 . _:b376135365 . _:b376136801 . _:b376136339 . _:b376135840 "3"^^ . _:b376135366 . . _:b376135367 . . _:b376135360 . _:b376135361 . _:b376136046 . _:b376135843 "3"^^ . . _:b376135362 . _:b376135363 . _:b376135388 . _:b376135389 . _:b376135842 "3"^^ . _:b376135390 . _:b376136029 . _:b376135391 . _:b3471591 . _:b376135384 . _:b376135385 . _:b376135853 "3"^^ . _:b376135386 . _:b376135387 . . _:b376135380 . _:b376135381 . _:b376135852 "3"^^ . _:b376135382 . _:b376135383 . _:b376135376 . . _:b376135855 "3"^^ . _:b376135377 . _:b376135378 . _:b376135379 . _:b3471571 "One potential target is the surface adhesins, and possible candidates include the surface proteins Atl, Bap, and SasG, all of which have reported roles in biofilm formation [41], [>>42<<], [71]\u2013[73]." . _:b376135404 . . _:b376135854 "3"^^ . _:b376135405 . _:b376135406 . _:b376135407 . _:b376135400 . _:b376135401 . _:b376135849 "3"^^ . _:b376135402 . _:b376135403 . _:b376135396 . _:b376135397 . _:b376135848 "3"^^ . _:b376135398 . _:b376135399 . _:b376135392 . _:b376135393 . _:b376135851 "3"^^ . . _:b376135394 . _:b376135395 . _:b376135420 . _:b376135421 . _:b376135850 "3"^^ . _:b376135422 . _:b376135423 . _:b376135416 . . _:b376135417 . _:b376135861 "3"^^ . _:b376135489 . _:b376135542 . _:b376135418 . _:b376135419 . _:b376135412 . _:b376135413 . _:b376135860 "3"^^ . _:b376135414 . _:b376135415 . . . _:b376135408 . . _:b376135863 "3"^^ . _:b376135409 . _:b376135410 . _:b376135411 . _:b376135436 . . _:b376135437 . _:b376135862 "3"^^ . _:b376135438 . _:b376136374 . _:b376135439 . _:b376135432 . _:b376135433 . _:b376135857 "3"^^ . . _:b376135434 . _:b376135916 . _:b376135435 . . _:b376135428 . . _:b376135429 . _:b376135856 "3"^^ . _:b376135430 . _:b376135431 . _:b376135424 . . _:b376135859 "3"^^ . _:b376135425 . . . _:b376135426 . _:b376135427 . _:b376135452 . _:b376136254 . . _:b376135858 "3"^^ . _:b376135453 . _:b376135454 . _:b376135976 . _:b376135208 . _:b376135455 . _:b376135448 . _:b376135449 . _:b376135869 "3"^^ . _:b376135450 . _:b376135451 . _:b376135444 . _:b376135445 . _:b376135868 "3"^^ . _:b376135446 . _:b376135447 . _:b376135440 . _:b376135441 . _:b376135871 "3"^^ . _:b376135442 . _:b376135443 . _:b376135468 . _:b376135469 . _:b376135870 "3"^^ . _:b376135470 . _:b3471544 . _:b376135471 . _:b376135464 . _:b376135465 . _:b376135865 "3"^^ . . _:b376135466 . _:b376135467 . _:b376135460 . _:b376135720 . _:b376135864 "3"^^ . _:b376135461 . . _:b376136761 . _:b376135462 . _:b3471437 . _:b376135463 . . _:b376136456 . _:b376135456 . _:b376135457 . _:b376135867 "3"^^ . _:b376135458 . _:b3471438 . _:b376135459 . _:b376135484 . _:b376135485 . _:b376135866 "3"^^ . _:b376135486 . _:b3471439 . _:b376136610 . _:b376135487 . _:b376135480 . _:b376135481 . _:b376135877 "3"^^ . _:b376135482 . _:b376135963 . _:b376135483 . _:b376136148 . . _:b376135476 . _:b376135477 . _:b376135876 "3"^^ . _:b376135478 . _:b376135479 . _:b376135472 . . _:b376135879 "3"^^ . _:b376135473 . . _:b376135474 . _:b376135475 . _:b376136606 . . _:b376135500 . _:b376135501 . _:b376135878 "3"^^ . _:b376135502 . _:b376135503 . . _:b376135496 . _:b376135497 . _:b376135873 "3"^^ . _:b376135498 . _:b3471444 . _:b376135499 . _:b376135492 . _:b376135493 . _:b376135872 "3"^^ . _:b376135494 . _:b3471445 . _:b376135495 . _:b376135488 . _:b376135489 . _:b376135875 "3"^^ . _:b376135490 . _:b3471446 . _:b376135491 . _:b376135665 . _:b376135516 . _:b376135517 . _:b376135874 "3"^^ . _:b376135518 . _:b3471447 . _:b376135519 . _:b376135512 . _:b376135513 . _:b376135885 "3"^^ . _:b376135514 . _:b3471440 . _:b376135515 . _:b376135508 . _:b376135509 . _:b376135884 "3"^^ . _:b376135757 . _:b3471441 . _:b376136639 . _:b376135510 . _:b376135511 . . _:b376135504 . _:b376135505 . _:b376136473 . _:b376135887 "3"^^ . _:b376135506 . _:b3471442 . _:b376135507 . _:b3471485 "For the experimental setup, a once-through, continuous culture system was employed as previously described [>>19<<],[25], and S. aureus SH1000 constitutively expressing red fluorescent protein (PsarA-RFP, plasmid pAH9) was used as the testing strain." . _:b376136770 . _:b376135532 . _:b376135533 . _:b376135886 "3"^^ . _:b376135534 . _:b3471443 . _:b376135535 . _:b376136619 . . _:b376135528 . _:b376135529 . _:b376135881 "3"^^ . _:b376135530 . _:b3471452 . _:b376135531 . _:b376135524 . _:b376135525 . _:b376135880 "3"^^ . _:b376135526 . _:b3471453 . _:b376135527 . _:b376135520 . _:b376135521 . _:b376135883 "3"^^ . _:b376135522 . _:b3471454 . _:b376135523 . _:b376135548 . _:b376135549 . _:b376135882 "3"^^ . _:b376135550 . _:b3471455 . _:b376135551 . _:b376135544 . _:b376135545 . _:b376135893 "3"^^ . _:b376135546 . _:b3471448 . _:b376135547 . _:b376135540 . _:b376135541 . _:b376135892 "3"^^ . _:b376135428 . . _:b3471449 . _:b376135542 . _:b376135543 . _:b376135213 . _:b376136592 . _:b376135536 . _:b376135537 . _:b376135895 "3"^^ . _:b376135538 . _:b3471450 . _:b376135539 . _:b376135564 . _:b376136011 . _:b376135565 . _:b376135894 "3"^^ . _:b376135566 . _:b3471451 . . _:b376135567 . _:b376136505 . _:b376135560 . _:b376135561 . _:b376135889 "3"^^ . _:b376135562 . _:b3471460 . _:b376135563 . _:b376135764 . _:b376135556 . _:b3471478 . _:b376136533 . _:b376135557 . _:b376135888 "3"^^ . _:b376135558 . _:b3471461 . _:b376135559 . . _:b376135552 . _:b376135891 "3"^^ . _:b376135553 . _:b376135554 . _:b3471462 . _:b376135555 . _:b376135580 . _:b376135890 "3"^^ . . _:b376135436 . _:b376135581 . _:b376135582 . _:b3471463 . _:b376135583 . _:b376135576 . _:b376135901 "3"^^ . _:b376136706 . _:b376135577 . _:b376135578 . _:b3471456 . _:b376135579 . _:b376135572 . _:b376135658 . _:b376135900 "3"^^ . _:b376135573 . _:b376135574 . _:b3471457 . _:b376135575 . _:b376135568 . . _:b376135903 "3"^^ . _:b376135569 . _:b376135570 . _:b3471458 . _:b376135571 . _:b376135596 . _:b376135902 "3"^^ . _:b376135597 . _:b376135598 . _:b3471459 . _:b376135599 . _:b376135592 . _:b376135897 "3"^^ . _:b376135593 . . _:b376135594 . _:b3471468 . _:b376135595 . _:b376135588 . _:b376135896 "3"^^ . _:b376135589 . _:b376135590 . _:b3471469 . _:b376135591 . _:b376135584 . _:b376135899 "3"^^ . _:b376135585 . . _:b376135586 . _:b3471470 . _:b376135587 . _:b376136042 . _:b376135612 . _:b376135898 "3"^^ . _:b376135613 . _:b376135614 . _:b3471471 . _:b376135861 . _:b376135615 . _:b376136787 . _:b376135909 "2"^^ . _:b376135608 . _:b376135609 . . _:b376135610 . _:b3471464 . _:b376135611 . _:b376136364 . _:b376135908 "2"^^ . _:b376135604 . _:b376135605 . _:b376135606 . _:b3471465 . _:b376136295 . _:b376135607 . _:b376135911 "2"^^ . _:b376135600 . . _:b376135601 . _:b376135602 . _:b3471466 . _:b376136636 . _:b376135603 . _:b376135910 "2"^^ . _:b376135628 . . _:b376135891 . _:b376135629 . _:b376135630 . _:b3471467 . . _:b376135631 . _:b376135905 "2"^^ . _:b376135624 . _:b376135625 . _:b376135626 . _:b3471476 . _:b376135627 . _:b376135904 "2"^^ . _:b376135620 . . _:b376135621 . _:b376135622 . _:b3471477 . _:b376136564 . _:b376135623 . _:b376135907 "2"^^ . _:b376135616 . . _:b376135617 . _:b376135618 . _:b3471478 . _:b376136603 . _:b376135619 . _:b376135906 "2"^^ . _:b376135644 . _:b376135591 . _:b376135645 . _:b376135709 . . _:b3471479 . _:b376135646 . _:b376135647 . _:b376135917 "2"^^ . _:b3471530 . _:b376135640 . _:b376135641 . _:b376135955 . _:b376135642 . _:b3471472 . . _:b376135643 . _:b376135916 "2"^^ . _:b376136008 . _:b376135636 . . _:b376135637 . _:b376135638 . _:b3471473 . _:b376135639 . _:b376135292 . _:b376135919 "2"^^ . _:b376135632 . _:b376135266 . _:b376135633 . _:b376135634 . _:b3471474 . _:b376135635 . _:b376135918 "2"^^ . _:b3471452 . _:b3471454 . _:b376135660 . _:b376135661 . _:b376135350 . _:b3471475 . _:b376135662 . _:b376135663 . _:b376135913 "2"^^ . _:b376135656 . _:b376135657 . _:b376135658 . _:b3471484 . _:b376135659 . _:b376135912 "2"^^ . _:b376135652 . _:b376135653 . . _:b3471485 . _:b376135654 . _:b376135655 . _:b376135915 "2"^^ . _:b376135648 . . _:b376135649 . _:b376135650 . _:b3471486 . . _:b3471437 . _:b376135651 . _:b376135914 "2"^^ . _:b376135676 . _:b376135622 . . _:b376135677 . . . _:b3471487 . _:b376135678 . . . _:b376136523 . _:b376135679 . _:b376135925 "2"^^ . _:b376136472 . . _:b376135672 . _:b376135673 . _:b376135674 . _:b3471480 . _:b376136745 . _:b376135675 . _:b376135924 "2"^^ . _:b376135668 . _:b376135669 . . _:b376135670 . _:b3471481 . _:b376135671 . _:b376135927 "2"^^ . _:b3471445 . _:b376135664 . _:b376135665 . _:b376136483 . _:b376135666 . _:b3471482 . _:b376135667 . _:b376135926 "2"^^ . _:b376135624 . . _:b3471483 . _:b376136785 . _:b376135921 "2"^^ . _:b376136808 . _:b3471492 . _:b3471477 . _:b376135920 "2"^^ . _:b3471493 . _:b3471547 "Alternatively, detachment studies have addressed effector gene products that contribute to the dissolution of the biofilm, including surfactants [10],[13],[64],[65], hydrolases [66],[67], proteases [37]\u2013[39], and DNase [>>68<<]. Here were do both, by demonstrating that the increasing AIP levels or lowering available glucose can function as a S. aureus biofilm detachment signal by activating the agr quorum-sensing system, resulting in increased levels of" . _:b376136818 . _:b376135923 "2"^^ . _:b376135287 . _:b3471494 . _:b376136147 . _:b376136108 . _:b376135922 "2"^^ . _:b3471495 . . _:b376135933 "2"^^ . _:b3471488 . . _:b376135637 . . _:b376135932 "2"^^ . _:b3471489 . . _:b376135935 "2"^^ . _:b376136150 . _:b3471490 . _:b376135934 "2"^^ . . . _:b3471491 . _:b376135929 "2"^^ . _:b376136819 . _:b3471500 . _:b376135928 "2"^^ . . _:b376135815 . _:b3471501 . _:b376135931 "2"^^ . . _:b3471502 . _:b376135930 "2"^^ . _:b3471503 . _:b376135941 "2"^^ . . _:b3471496 . _:b376136145 . _:b376135940 "2"^^ . _:b3471497 . _:b376135943 "2"^^ . . _:b3471498 . _:b376135942 "2"^^ . _:b3471499 . _:b376135937 "2"^^ . _:b3471508 . _:b376135936 "2"^^ . _:b3471509 . _:b376135252 . _:b376135939 "2"^^ . _:b376135567 . _:b3471510 . _:b376135938 "2"^^ . _:b3471511 . _:b376135949 "2"^^ . _:b3471504 . _:b376136268 . _:b376135948 "2"^^ . _:b3471505 . _:b376135951 "2"^^ . . _:b376136278 . _:b3471506 . _:b376135950 "2"^^ . . _:b376136756 . _:b3471507 . . _:b376135945 "2"^^ . . . _:b3471516 . _:b376135944 "2"^^ . . _:b3471517 . _:b376135947 "2"^^ . _:b3471518 . _:b376135946 "2"^^ . . _:b3471519 . _:b376135957 "2"^^ . _:b376136687 . _:b3471512 . . _:b376135956 "2"^^ . _:b376135323 . . _:b376136051 . _:b3471513 . _:b376135959 "2"^^ . _:b376136739 . _:b376135960 . _:b376135819 . _:b3471514 . _:b376135958 "2"^^ . . . _:b3471515 . . _:b376135953 "2"^^ . . _:b3471524 . _:b376135952 "2"^^ . _:b376135869 . _:b3471525 . _:b376135955 "2"^^ . . . _:b3471526 . _:b376135954 "2"^^ . . _:b376135399 . _:b376136671 . _:b3471527 . _:b376136437 . _:b376135965 "2"^^ . _:b3471520 . _:b376135964 "2"^^ . _:b3471521 . _:b376135462 . _:b376135427 . _:b376135967 "2"^^ . _:b3471522 . _:b376135692 . _:b376135903 . _:b376135966 "2"^^ . . _:b376135366 . _:b3471523 . _:b376135961 "2"^^ . . _:b3471532 . _:b376135960 "2"^^ . _:b376135839 . . _:b3471533 . _:b376135963 "2"^^ . _:b3471534 . _:b376136491 . _:b376135962 "2"^^ . . _:b3471535 . _:b376135973 "2"^^ . _:b3471528 . _:b376135972 "2"^^ . . _:b3471529 . . _:b376135975 "2"^^ . _:b376136581 . _:b3471530 . _:b376136854 . _:b376136638 . _:b376135974 "2"^^ . . _:b3471531 . _:b376135969 "2"^^ . _:b3471568 "Global expression analysis has shown that activation of the agr quorum-sensing system results in up-regulation of extracellular proteases (Aur, SplABCDEF, ScpA, SspAB) and down-regulation of many surface proteins [>>45<<],[46]. However, the target of these agr controlled proteases is not clear. One potential target is the surface adhesins, and possible candidates include the surface proteins Atl, Bap, and SasG, all of which have reported roles in biofilm" . _:b376135421 . _:b3471540 . _:b376135968 "2"^^ . _:b376136121 . _:b3471541 . _:b376136366 . _:b376135971 "2"^^ . . . _:b3471542 . _:b376135970 "2"^^ . . . _:b3471543 . _:b376135981 "2"^^ . . _:b3471536 . _:b376135980 "2"^^ . _:b3471490 . . _:b3471537 . _:b376135397 . _:b376135983 "2"^^ . . _:b376135546 . _:b3471473 . _:b3471538 . _:b376135982 "2"^^ . . . _:b3471518 "There are 10 known extracellular proteases produced by most S. aureus strains and expression of all these enzymes is controlled by the agr system [>>18<<],[45],[46]. These 10 proteases include the metalloprotease aureolysin (aur), two cysteine proteases (scpA and sspB), and seven serine proteases (sspA (V8) and splABCDEF) [47]." . _:b3471539 . _:b376135977 "2"^^ . _:b3471495 . _:b3471534 "The majority of studies on biofilm detachment have focused on factors capable of initiating the process, such as nutrient availability [54],[55], nitric oxide exposure [56], oxygen tension [>>57<<], iron salts [58], chelators [59], and signaling molecules [60]\u2013[63]." . _:b3471548 . _:b376135976 "2"^^ . . _:b3471549 . _:b376135979 "2"^^ . _:b3471550 . _:b376135978 "2"^^ . _:b376135922 . . _:b3471551 . _:b376135989 "2"^^ . _:b376136517 . _:b3471544 . _:b376135988 "2"^^ . . _:b3471545 . _:b376135991 "2"^^ . . . _:b3471546 . _:b376135990 "2"^^ . _:b3471547 . _:b376135985 "2"^^ . _:b376135604 . _:b3471556 . . _:b376135984 "2"^^ . _:b3471557 . _:b376135987 "2"^^ . _:b3471558 . _:b376136143 . _:b376135986 "2"^^ . _:b376136684 . _:b3471559 . _:b376136455 . _:b376135997 "2"^^ . _:b3471552 . _:b376135996 "2"^^ . _:b376135504 . _:b3471553 . _:b376135999 "2"^^ . _:b3471554 . _:b376135998 "2"^^ . _:b3471555 . _:b376135993 "2"^^ . _:b3471564 . _:b376135992 "2"^^ . _:b3471565 . _:b376135995 "2"^^ . _:b3471566 . _:b376135994 "2"^^ . _:b3471567 . . _:b376136005 "2"^^ . _:b3471540 "Alternatively, detachment studies have addressed effector gene products that contribute to the dissolution of the biofilm, including surfactants [10],[>>13<<],[64],[65], hydrolases [66],[67], proteases [37]\u2013[39], and DNase [68]." . _:b3471560 . _:b376136004 "2"^^ . _:b3471561 . _:b376136007 "2"^^ . _:b3471562 . _:b376136006 "2"^^ . . _:b3471563 . _:b376136001 "2"^^ . _:b3471531 "The majority of studies on biofilm detachment have focused on factors capable of initiating the process, such as nutrient availability [>>54<<],[55], nitric oxide exposure [56], oxygen tension [57], iron salts [58], chelators [59], and signaling molecules [60]\u2013[63]." . . _:b3471572 . _:b376136000 "2"^^ . _:b3471573 . . _:b376136003 "2"^^ . _:b376135290 . _:b376135956 . _:b3471574 . _:b376136002 "2"^^ . . _:b3471575 . . . _:b376136013 "2"^^ . _:b3471568 . . . _:b376136012 "2"^^ . _:b3471569 . _:b376136015 "2"^^ . _:b376136409 . _:b376136362 . _:b3471570 . . . _:b376136014 "2"^^ . . . . _:b3471571 . . _:b376136009 "2"^^ . . . _:b3471580 . . . _:b376136008 "2"^^ . _:b376136834 . . _:b3471581 . _:b376136011 "2"^^ . _:b3471582 . _:b376136010 "2"^^ . _:b3471543 "Alternatively, detachment studies have addressed effector gene products that contribute to the dissolution of the biofilm, including surfactants [10],[13],[64],[65], hydrolases [>>66<<],[67], proteases [37]\u2013[39], and DNase [68]." . _:b3471583 . . _:b376136021 "2"^^ . _:b3471576 . _:b376135878 . _:b376136020 "2"^^ . _:b3471577 . _:b376135686 . _:b3471530 "discussion" . _:b376136023 "2"^^ . _:b376136348 . . _:b3471578 . _:b376135445 . _:b376136022 "2"^^ . _:b376135826 . _:b376136112 . _:b3471579 . . _:b376136017 "2"^^ . _:b3471588 . _:b376136000 . _:b376136016 "2"^^ . _:b376136519 . _:b3471589 . . _:b3471580 "Surfactant-like molecules, such as \u03B4-toxin, are induced by the agr system and may exert dispersal effects on biofilms [13],[>>78<<]. There is growing evidence that extracellular DNA (eDNA) is an important S. aureus biofilm matrix component [24],[70], and expression of staphylococcal nuclease is reported to be under control of the agr system [18]. Thus, while agr" . _:b376136019 "2"^^ . _:b376135195 . _:b3471590 . _:b376136331 . _:b376136018 "2"^^ . . _:b376135953 . _:b3471591 . _:b376136029 "2"^^ . _:b3471584 . _:b376136521 . _:b376136028 "2"^^ . _:b3471585 . _:b376136031 "2"^^ . _:b3471438 . _:b3471586 . _:b376135782 . _:b376136030 "2"^^ . _:b3471587 . . _:b376136025 "2"^^ . _:b376136024 "2"^^ . . . _:b376136027 "2"^^ . . _:b376136026 "2"^^ . _:b376136037 "2"^^ . _:b376136250 . . _:b376136036 "2"^^ . _:b376136326 . _:b376136039 "2"^^ . _:b376136337 . _:b376136038 "2"^^ . _:b376135495 . _:b3471452 "These findings correlate well with prior data indicating that agr deficient S. aureus strains form more robust biofilms compared to wild type strains [>>13<<],[14]." . _:b376136033 "2"^^ . _:b3471440 "The challenge presented by biofilm infections is the remarkable resistance to both host immune responses and available chemotherapies [6],[>>7<<], and estimates suggest that as many as 80% of chronic bacterial infections are biofilm associated [8]." . . . _:b376136635 . _:b376136032 "2"^^ . _:b376136035 "2"^^ . _:b376136344 . . _:b376136034 "2"^^ . . _:b376135388 . _:b376136045 "2"^^ . . . _:b376136044 "2"^^ . _:b376135191 "26"^^ . _:b376136047 "2"^^ . . _:b376136104 . _:b376135190 "28"^^ . _:b376136046 "2"^^ . . _:b376135189 "28"^^ . _:b376136041 "2"^^ . . . _:b376135188 "29"^^ . _:b376136040 "2"^^ . _:b376135735 . _:b376135194 "25"^^ . _:b376136043 "2"^^ . _:b376135211 . _:b376135195 "25"^^ . _:b376136042 "2"^^ . . _:b376136053 "2"^^ . _:b3471579 . _:b376135192 "26"^^ . _:b376135193 "25"^^ . _:b376136620 . _:b376136052 "2"^^ . . . _:b376135198 "22"^^ . _:b376136055 "2"^^ . _:b376135199 "22"^^ . _:b376136054 "2"^^ . _:b376135196 "24"^^ . _:b376136049 "2"^^ . _:b376135197 "24"^^ . . _:b376136204 . _:b376136048 "2"^^ . _:b376135201 "21"^^ . _:b376136178 . _:b376136051 "2"^^ . _:b376136050 "2"^^ . _:b376135200 "22"^^ . _:b376135203 "20"^^ . _:b376135585 . _:b376136061 "2"^^ . _:b376136662 . _:b376135441 . _:b376135202 "20"^^ . _:b376136060 "2"^^ . _:b376135205 "19"^^ . . _:b376136063 "2"^^ . _:b376135204 "19"^^ . . _:b376136062 "2"^^ . _:b376135207 "18"^^ . _:b376135978 . _:b376136057 "2"^^ . _:b376135206 "19"^^ . _:b376136430 . _:b376135300 . _:b376135974 . _:b376136056 "2"^^ . _:b376135209 "18"^^ . _:b376136764 . _:b376136059 "2"^^ . _:b376136357 . _:b376135208 "18"^^ . _:b376136058 "2"^^ . _:b376135802 . . _:b376135534 . _:b376136069 "2"^^ . _:b376135210 "18"^^ . _:b376136146 . . _:b376135211 "17"^^ . _:b376136068 "2"^^ . . _:b376135212 "17"^^ . _:b376136071 "2"^^ . _:b376135213 "17"^^ . _:b376136081 . _:b376136070 "2"^^ . _:b376135214 "16"^^ . _:b376136065 "2"^^ . _:b376135565 . _:b376135468 . _:b376135215 "15"^^ . _:b376136064 "2"^^ . _:b376135216 "14"^^ . _:b3471466 . . _:b376135223 "13"^^ . _:b376136067 "2"^^ . . _:b376135217 "14"^^ . _:b376136840 . _:b376135222 "13"^^ . _:b3471583 "There is growing evidence that extracellular DNA (eDNA) is an important S. aureus biofilm matrix component [24],[70], and expression of staphylococcal nuclease is reported to be under control of the agr system [>>18<<]. Thus, while agr induced proteases are required for the detachment phenotype, the agr controlled expression of an array of factors (proteases, nuclease, surfactants) may also contribute to the biofilm detachment mechanism." . _:b376136066 "2"^^ . . . _:b376135218 "14"^^ . . _:b376135221 "13"^^ . _:b376136077 "2"^^ . . _:b376135219 "14"^^ . _:b376135767 . _:b376135220 "13"^^ . _:b376136076 "2"^^ . . _:b376135828 . . _:b376136079 "2"^^ . . _:b3471548 . _:b376136078 "2"^^ . . . _:b376136073 "2"^^ . _:b376136072 "2"^^ . _:b376135231 "12"^^ . _:b376136075 "2"^^ . _:b376136711 . . _:b376135230 "13"^^ . _:b376136074 "2"^^ . _:b376136182 . _:b376135229 "13"^^ . _:b376136085 "2"^^ . _:b376135228 "13"^^ . _:b376136084 "2"^^ . _:b376135227 "13"^^ . _:b376136087 "2"^^ . _:b376135226 "13"^^ . _:b3471540 . _:b376136086 "2"^^ . . _:b376135652 . _:b376135225 "13"^^ . _:b376136081 "2"^^ . _:b376135224 "13"^^ . _:b376136080 "2"^^ . _:b376135239 "11"^^ . _:b376136083 "2"^^ . . _:b376135238 "11"^^ . _:b376136082 "2"^^ . . _:b376135237 "11"^^ . _:b376136342 . _:b376136093 "2"^^ . _:b376135236 "11"^^ . _:b376136803 . _:b376136092 "2"^^ . . . _:b376135235 "11"^^ . . _:b376135371 . _:b376136095 "2"^^ . _:b376135234 "11"^^ . _:b376136602 . _:b376136094 "2"^^ . _:b376135233 "12"^^ . _:b376136089 "2"^^ . _:b376135232 "12"^^ . _:b376136727 . _:b376136088 "2"^^ . _:b376135247 "10"^^ . . _:b376136091 "2"^^ . _:b376135246 "10"^^ . . _:b376136090 "2"^^ . _:b376135245 "10"^^ . . _:b376136101 "2"^^ . _:b376136246 . _:b376135244 "10"^^ . . _:b376136100 "2"^^ . _:b376135243 "10"^^ . _:b376136012 . _:b376135475 . _:b376136103 "2"^^ . . _:b376135948 . _:b376135242 "11"^^ . _:b376136403 . _:b376136102 "2"^^ . _:b376135241 "11"^^ . _:b3471582 . _:b376135743 . _:b376136097 "2"^^ . _:b376135240 "11"^^ . _:b376136180 . _:b376136096 "2"^^ . _:b376135255 "10"^^ . . _:b376136099 "2"^^ . _:b376135254 "10"^^ . . _:b376136098 "2"^^ . _:b376135989 . . _:b376135253 "10"^^ . . . _:b376136109 "2"^^ . _:b376135406 . _:b376135252 "10"^^ . . _:b376136108 "2"^^ . _:b376135251 "10"^^ . _:b376136111 "2"^^ . _:b376135250 "10"^^ . _:b376136198 . _:b376136110 "2"^^ . _:b376135249 "10"^^ . . _:b376136105 "2"^^ . _:b376135248 "10"^^ . _:b376135370 . _:b376135244 . _:b376136104 "2"^^ . _:b376135262 "9"^^ . _:b376136107 "2"^^ . _:b376135263 "9"^^ . _:b376136370 . _:b376136106 "2"^^ . _:b376136127 . . _:b376135260 "9"^^ . _:b376136584 . _:b376136117 "2"^^ . . _:b376135972 . . _:b376135261 "9"^^ . _:b376136116 "2"^^ . . _:b376135949 . _:b376135258 "9"^^ . _:b376136119 "2"^^ . _:b376135259 "9"^^ . _:b376136118 "2"^^ . _:b376136113 "2"^^ . _:b376135256 "10"^^ . _:b376135257 "9"^^ . _:b376136112 "2"^^ . _:b3471564 . _:b376135270 "9"^^ . _:b376136426 . _:b376136115 "2"^^ . . _:b376135467 . _:b3471563 . _:b376135403 . . _:b376135271 "9"^^ . _:b376136114 "2"^^ . _:b3471459 . _:b376135268 "9"^^ . _:b376136125 "2"^^ . _:b376136125 . _:b376135345 . _:b376136732 . _:b376136333 . _:b3471456 . _:b376135269 "9"^^ . _:b376136124 "2"^^ . . _:b376135632 . _:b3471457 . _:b376135266 "9"^^ . _:b376136127 "2"^^ . . _:b3471506 "While SH1000 is a derivative of 8325-4, and there are reports that the ica locus is required for 8325-4 derived strains to make a biofilm [>>36<<], the ica locus was not required for biofilm formation under our experimental conditions." . _:b376135267 "9"^^ . _:b376136126 "2"^^ . . _:b376135742 . _:b376135264 "9"^^ . _:b376136121 "2"^^ . _:b376135623 . . _:b376135265 "9"^^ . _:b376136120 "2"^^ . _:b376135278 "8"^^ . _:b376136123 "2"^^ . _:b376136827 . _:b376135279 "8"^^ . _:b376136077 . _:b376136122 "2"^^ . _:b376135276 "8"^^ . _:b376136133 "2"^^ . . _:b376135277 "8"^^ . . _:b376136132 "2"^^ . . . _:b376135274 "8"^^ . _:b376136135 "2"^^ . _:b376135275 "8"^^ . . _:b376136134 "2"^^ . _:b376135272 "8"^^ . _:b376136129 "2"^^ . . _:b3471483 "Interestingly, in most published flow cell biofilm studies, one commonality is the use of growth media containing or supplemented with glucose [9], [19], [>>21<<]\u2013[24]. In our own efforts to grow S. aureus flow cell biofilms, we found a strict dependence on glucose supplementation. For the experimental setup, a once-through, continuous culture system was employed as previously described [19],[25]," . _:b376136210 . _:b376136718 . _:b376135273 "8"^^ . _:b376135987 . _:b376136128 "2"^^ . _:b376135286 "8"^^ . _:b376135575 . . _:b376136131 "2"^^ . . _:b376136595 . _:b376135287 "8"^^ . _:b376136130 "2"^^ . _:b376135741 . _:b376135284 "8"^^ . _:b376136141 "2"^^ . _:b376135285 "8"^^ . _:b376136140 "2"^^ . . _:b376135188 . . . . _:b376135282 "8"^^ . _:b376135336 . _:b376135851 . _:b376135476 . _:b376136143 "2"^^ . . _:b376135283 "8"^^ . _:b376136142 "2"^^ . _:b376136799 . _:b376135280 "8"^^ . _:b376136137 "2"^^ . _:b3471463 . _:b376135281 "8"^^ . . _:b376135498 . _:b376136136 "2"^^ . _:b376136798 . . _:b376135294 "8"^^ . _:b376136139 "2"^^ . _:b376135295 "8"^^ . _:b376136138 "2"^^ . _:b376135292 "8"^^ . _:b376136149 "2"^^ . . _:b3471565 "material is important for SH1000 biofilm integrity, and this result supports a number of recent studies demonstrating that proteases can inhibit biofilm formation or detach established biofilms from many S. aureus strains [>>35<<], [37]\u2013[39]. It is not clear whether agr-mediated detachment will function in S. aureus strains that produce an ica-dependent biofilm." . _:b376135293 "8"^^ . _:b376135696 . _:b376135206 . _:b376136148 "2"^^ . . _:b376135290 "8"^^ . . _:b376136151 "2"^^ . _:b376136815 . _:b376135291 "8"^^ . . _:b376136150 "2"^^ . _:b376136413 . _:b376135288 "8"^^ . . _:b376136766 . _:b376136145 "2"^^ . _:b376136681 . _:b376135289 "8"^^ . . _:b376136144 "2"^^ . _:b376135277 . _:b376135519 . _:b376135302 "7"^^ . _:b376136147 "2"^^ . _:b3471481 "Interestingly, in most published flow cell biofilm studies, one commonality is the use of growth media containing or supplemented with glucose [>>9<<], [19], [21]\u2013[24]." . _:b376135303 "7"^^ . _:b376136146 "2"^^ . _:b376135300 "7"^^ . _:b376136157 "2"^^ . _:b376135301 "7"^^ . . _:b376136156 "2"^^ . _:b376135298 "7"^^ . _:b376136159 "2"^^ . _:b376135299 "7"^^ . _:b376135751 . _:b376136158 "2"^^ . . . _:b376135296 "8"^^ . _:b376136153 "2"^^ . _:b3471447 . _:b376135297 "7"^^ . _:b376135685 . . _:b376136152 "2"^^ . _:b376135310 "7"^^ . _:b376136155 "2"^^ . _:b376135311 "7"^^ . _:b376136154 "2"^^ . _:b376135308 "7"^^ . _:b376136383 . . . _:b376136165 "2"^^ . _:b376135309 "7"^^ . _:b3471507 "Similar to our observations, an ica mutant of the clinical S. aureus isolate UAMS-1 displays no defect in microtiter and flow cell biofilm assays [>>22<<]. In contrast, when proteinase K was added to SH1000, biofilms were unable to develop in the microtiter plate format (data not shown), indicating the biofilms are forming through an ica-independent mechanism. These findings suggest that" . . _:b376136164 "2"^^ . _:b376135306 "7"^^ . . _:b376136167 "2"^^ . . _:b376135307 "7"^^ . _:b376135834 . _:b376136166 "2"^^ . _:b376135304 "7"^^ . _:b376136161 "2"^^ . _:b376135305 "7"^^ . . . _:b376136160 "2"^^ . _:b376135318 "7"^^ . _:b376135588 . _:b376135283 . _:b376136163 "2"^^ . _:b376135319 "7"^^ . . . _:b376136162 "2"^^ . _:b376135857 . _:b376135316 "7"^^ . _:b376136173 "2"^^ . _:b376135317 "7"^^ . . _:b376136172 "2"^^ . _:b376135765 . _:b376135314 "7"^^ . _:b376136175 "2"^^ . _:b376136343 . _:b376135315 "7"^^ . _:b376136763 . _:b376136372 . _:b376136174 "2"^^ . _:b376135312 "7"^^ . _:b376136169 "2"^^ . _:b376135313 "7"^^ . _:b376136168 "2"^^ . _:b376135752 . . _:b3471521 . _:b376135326 "7"^^ . _:b376136171 "2"^^ . _:b376135327 "7"^^ . _:b376136170 "2"^^ . _:b376135324 "7"^^ . _:b376135246 . _:b376136181 "2"^^ . _:b376135325 "7"^^ . . _:b376136180 "2"^^ . _:b376135322 "7"^^ . . _:b376136183 "2"^^ . _:b376136833 . _:b376136618 . _:b376135323 "7"^^ . _:b376136182 "2"^^ . _:b376135320 "7"^^ . _:b376136624 . . _:b376136177 "2"^^ . _:b376135321 "7"^^ . _:b376136176 "2"^^ . _:b376135334 "6"^^ . _:b3471545 . _:b376135929 . _:b376136179 "2"^^ . _:b3471528 "The activation mechanism of the ScpA cysteine protease remains unresolved [>>49<<]. In contrast to the serine protease mutations, introduction of the \u0394aur deletion into S. aureus reduced extracellular protease levels (Figure 10A) and did not affect biofilm formation (Figure 10B)." . _:b376135335 "6"^^ . _:b376135631 . _:b376136178 "2"^^ . _:b376136676 . _:b376135332 "6"^^ . _:b376135845 . _:b376135902 . _:b376136310 . _:b376136189 "2"^^ . _:b376135333 "6"^^ . . _:b376136188 "2"^^ . _:b376136434 . _:b376135330 "6"^^ . . _:b376136416 . _:b376136191 "2"^^ . _:b376135331 "6"^^ . . _:b376136190 "2"^^ . _:b3471557 "Biofilms are dynamic and dispersal is always operating [11], but accelerated detachment has been observed in response to changing environmental conditions, such as oxygen levels [>>57<<],[69], nutrient depletion [54], changing nutrient composition [55], or increased concentration of quorum-sensing signals [61]." . _:b376135328 "7"^^ . _:b376136185 "2"^^ . _:b376135329 "7"^^ . . _:b376136184 "2"^^ . _:b376135342 "6"^^ . _:b376136187 "2"^^ . _:b376135343 "6"^^ . _:b376135484 . _:b376136186 "2"^^ . _:b376135340 "6"^^ . _:b3471461 . _:b376135341 "6"^^ . _:b3471460 . _:b376135338 "6"^^ . . . _:b376135339 "6"^^ . . _:b376136044 . _:b376135336 "6"^^ . . _:b376135337 "6"^^ . _:b3471515 . _:b376135271 . _:b376135289 . _:b376135350 "6"^^ . . _:b376135260 . _:b376135351 "6"^^ . _:b376135348 "6"^^ . _:b376135520 . _:b376135349 "6"^^ . _:b376135346 "6"^^ . . _:b376135347 "6"^^ . _:b376135344 "6"^^ . _:b376135345 "6"^^ . _:b376135358 "6"^^ . _:b376136580 . _:b376136136 . _:b376135359 "6"^^ . . _:b376135356 "6"^^ . _:b3471589 "However, homoserine lactone signals play a divergent role in Pseudomonas aeuruginosa [>>12<<], Pseudomonas fluorescens [82], and Burkholderia cepacia [83], where the active versions of these quorum-sensing systems are necessary for biofilm formation and robustness under some growth conditions." . _:b376135357 "6"^^ . _:b376135946 . _:b376135354 "6"^^ . _:b3471509 . _:b376135355 "6"^^ . _:b376135549 . _:b376135352 "6"^^ . _:b376135353 "6"^^ . _:b376135366 "6"^^ . _:b376135453 . . _:b376135204 . _:b376135367 "6"^^ . . . . _:b376136656 . _:b376135364 "6"^^ . . . . _:b376135365 "6"^^ . _:b376136228 . _:b376135362 "6"^^ . . . _:b376135363 "6"^^ . _:b376136396 . _:b376135360 "6"^^ . _:b376136535 . _:b376135361 "6"^^ . . _:b376135373 "5"^^ . _:b376136004 . _:b376136522 . _:b376135372 "5"^^ . _:b3471486 . . . _:b376135375 "5"^^ . . _:b376136293 . _:b376135374 "5"^^ . _:b376135370 "6"^^ . _:b376135636 . . _:b376135386 . _:b376135368 "6"^^ . _:b376135583 . _:b376135371 "5"^^ . _:b376136637 . _:b376135369 "6"^^ . . _:b3471569 "Global expression analysis has shown that activation of the agr quorum-sensing system results in up-regulation of extracellular proteases (Aur, SplABCDEF, ScpA, SspAB) and down-regulation of many surface proteins [45],[>>46<<]. However, the target of these agr controlled proteases is not clear. One potential target is the surface adhesins, and possible candidates include the surface proteins Atl, Bap, and SasG, all of which have reported roles in biofilm" . _:b376135381 "5"^^ . _:b376136709 . . _:b376135380 "5"^^ . . _:b376136708 . . _:b3471588 "Quorum-sensing has been implicated in dispersal of biofilms formed by Yersinia pseudotuberculosis [79], Rhodobacter sphaeroides [80], Pseudomonas aureofaciens [81], Xanthomonas capmestris [62], and Serratia marceascens [>>61<<]. However, homoserine lactone signals play a divergent role in Pseudomonas aeuruginosa [12], Pseudomonas fluorescens [82], and Burkholderia cepacia [83], where the active versions of these quorum-sensing systems are necessary for biofilm" . _:b376136774 . _:b376135383 "5"^^ . _:b376136711 . . _:b376135382 "5"^^ . _:b376136710 . _:b376135377 "5"^^ . _:b376136705 . _:b376136105 . _:b376135376 "5"^^ . _:b376136704 . _:b376135921 . _:b376135379 "5"^^ . . _:b376136707 . _:b376135378 "5"^^ . _:b376136706 . _:b376135864 . _:b376135389 "5"^^ . _:b376136717 . _:b376135388 "5"^^ . _:b376135872 . _:b376136716 . _:b376135391 "5"^^ . _:b376136719 . . _:b376135390 "5"^^ . _:b376136718 . _:b376135385 "5"^^ . _:b376136786 . _:b376136583 . . _:b376136713 . _:b376136591 . _:b376135384 "5"^^ . . _:b376135660 . _:b376136712 . _:b376135449 . _:b376135387 "5"^^ . _:b376136715 . . . _:b376135386 "5"^^ . _:b376136714 . _:b376136586 . . _:b376135397 "5"^^ . . _:b376136725 . _:b376135396 "5"^^ . _:b376136724 . . . _:b376135399 "5"^^ . _:b376136727 . _:b3471561 "S. aureus has been reported to form biofilms through an ica-dependent mechanism suggesting that PIA could have a role in detachment [>>34<<],[36]. We observed no defect in microtiter or flow cell biofilm formation using an ica mutant of SH1000 (Figure 7)." . _:b376135398 "5"^^ . _:b376136726 . . _:b376135393 "5"^^ . _:b376136721 . . _:b376135392 "5"^^ . _:b376135395 . _:b376136720 . . _:b376135395 "5"^^ . . _:b376136723 . _:b376135394 "5"^^ . _:b376136722 . _:b376135723 . _:b376135405 "5"^^ . _:b376136733 . _:b376135404 "5"^^ . _:b376135666 . _:b376136732 . _:b376135407 "5"^^ . _:b376136080 . _:b376136735 . _:b376135406 "5"^^ . _:b376136734 . _:b376136154 . _:b376135401 "5"^^ . _:b376135374 . _:b376136729 . _:b376136279 . _:b376135400 "5"^^ . _:b376136844 . _:b376135729 . _:b376136728 . _:b376135403 "5"^^ . _:b376136731 . _:b376135402 "5"^^ . _:b376136730 . . _:b376135413 "5"^^ . _:b376136741 . _:b376135964 . . _:b376135412 "5"^^ . _:b376136740 . _:b376135415 "5"^^ . . _:b3471566 . _:b376136743 . _:b376135414 "5"^^ . _:b376136742 . _:b376135409 "5"^^ . _:b3471522 . _:b376136737 . _:b376136144 . . _:b376135408 "5"^^ . _:b376136736 . . _:b376135487 . . _:b376135411 "5"^^ . _:b376136739 . _:b376135410 "5"^^ . _:b376136574 . _:b376136738 . . _:b3471580 . . . _:b376135421 "5"^^ . . _:b376136749 . . _:b376136811 . _:b376135420 "5"^^ . _:b376135627 . . . _:b376136748 . . _:b376135423 "5"^^ . . _:b376136751 . _:b376136680 . _:b376136702 . _:b376135422 "5"^^ . . _:b376136750 . _:b376135274 . _:b376135417 "5"^^ . _:b376136745 . _:b376135644 . . _:b376135915 . _:b376135416 "5"^^ . _:b376135426 . _:b376136744 . . _:b376135419 "5"^^ . _:b376136747 . . _:b376135418 "5"^^ . _:b376135594 . _:b376136746 . . _:b376135429 "5"^^ . _:b376136757 . . . . _:b3471573 . _:b376135428 "5"^^ . _:b376136756 . _:b376135431 "5"^^ . _:b376136759 . . _:b376136412 . _:b376135430 "5"^^ . _:b376135311 . _:b376136758 . _:b376135870 . _:b376135415 . _:b376135425 "5"^^ . _:b376135908 . _:b376135454 . _:b3471513 "S. aureus is coated with cell wall attached proteins that mediate adherence to a variety of substrates [40], and some of these adhesins, such as biofilm associated protein (BAP) and SasG are important for biofilm formation [41],[>>42<<]. It is also known that some surface adhesins, such as protein A and fibronectin-binding protein, are cleaved by the native S. aureus secreted proteases [43],[44]." . _:b376136753 . . . . _:b376135424 "5"^^ . _:b376136752 . _:b376135756 . _:b376135427 "5"^^ . . _:b376136755 . . _:b376135426 "5"^^ . _:b376136754 . _:b376135437 "5"^^ . _:b376136765 . _:b376136330 . _:b376135436 "5"^^ . _:b376136764 . _:b376135439 "4"^^ . _:b376136541 . _:b376136767 . _:b376135438 "4"^^ . _:b376136766 . _:b376136542 . . . _:b376135433 "5"^^ . _:b376136761 . _:b376135432 "5"^^ . _:b376136760 . _:b3471584 . _:b376135435 "5"^^ . _:b376136726 . _:b376136763 . _:b376135434 "5"^^ . _:b376135809 . _:b376136762 . _:b376135445 "4"^^ . _:b376136724 . _:b376136773 . _:b376135444 "4"^^ . . . _:b376136772 . _:b376136651 . _:b376135447 "4"^^ . _:b376136775 . _:b376135446 "4"^^ . _:b376136774 . . . _:b376135441 "4"^^ . _:b376136769 . . _:b376135440 "4"^^ . _:b376136631 . _:b376136768 . _:b376135443 "4"^^ . _:b376136060 . _:b376136376 . _:b376136771 . . _:b376135721 . _:b376135442 "4"^^ . _:b376136616 . _:b376136770 . _:b376135453 "4"^^ . _:b376136166 . _:b376136781 . _:b376135474 . _:b376135452 "4"^^ . _:b376136780 . _:b376135455 "4"^^ . . _:b376136783 . _:b3471492 "Since AIP-I and AIP-IV differ by only one amino acid and function interchangeably [28], they are grouped together in the classification scheme, although this assignment has been controversial [>>29<<],[30]." . _:b376135247 . _:b376135454 "4"^^ . _:b3471536 "The majority of studies on biofilm detachment have focused on factors capable of initiating the process, such as nutrient availability [54],[55], nitric oxide exposure [56], oxygen tension [57], iron salts [58], chelators [>>59<<], and signaling molecules [60]\u2013[63]." . _:b376136782 . _:b376135449 "4"^^ . _:b376136777 . _:b376135448 "4"^^ . _:b3471500 . _:b376136776 . _:b376135451 "4"^^ . _:b376136779 . _:b376135450 "4"^^ . _:b376136253 . _:b376136559 . _:b376136778 . _:b376136797 . _:b376135222 . _:b376136164 . _:b376135461 "4"^^ . _:b376135231 . _:b376136789 . _:b376135663 . . _:b376135460 "4"^^ . . _:b376136788 . . _:b376135463 "4"^^ . _:b376136791 . . _:b376135462 "4"^^ . _:b376136563 . _:b376136048 . _:b376136417 . _:b376136790 . _:b376135457 "4"^^ . _:b3471572 . _:b376136785 . _:b376135456 "4"^^ . _:b3471538 . _:b376136784 . . _:b376135619 . _:b376135459 "4"^^ . _:b376136787 . _:b376135759 . _:b376136126 . _:b376135458 "4"^^ . _:b376136299 . _:b376136786 . _:b376135469 "4"^^ . _:b376135304 . _:b376136797 . _:b3471505 "S. aureus is known to form biofilms through both ica-dependent and ica-independent mechanisms [34],[>>35<<]. To gain insight on the biofilm detachment mechanism, we sought to distinguish whether our S. aureus biofilms were dependent on PIA. In strain SH1000, we constructed an \u0394ica::Tet deletion mutant (strain AH595) using generalized" . _:b376135468 "4"^^ . . _:b376136796 . _:b376135471 "4"^^ . . . _:b376136799 . _:b376135818 . _:b376136722 . _:b376135470 "4"^^ . _:b376136798 . _:b376136772 . _:b376135820 . _:b376135465 "4"^^ . _:b376136793 . _:b376135464 "4"^^ . _:b376135512 . _:b376136189 . _:b376136792 . _:b376135467 "4"^^ . . . _:b376136795 . _:b376135466 "4"^^ . _:b3471439 . . . _:b376136794 . _:b3471579 "Surfactant-like molecules, such as \u03B4-toxin, are induced by the agr system and may exert dispersal effects on biofilms [>>13<<],[78]. There is growing evidence that extracellular DNA (eDNA) is an important S. aureus biofilm matrix component [24],[70], and expression of staphylococcal nuclease is reported to be under control of the agr system [18]. Thus, while agr" . _:b376135477 "4"^^ . . . _:b376136805 . _:b376136701 . _:b376135476 "4"^^ . _:b376136754 . _:b376136486 . _:b376136804 . _:b376135479 "4"^^ . _:b376135829 . _:b376136807 . _:b376135478 "4"^^ . _:b376136806 . . _:b376135473 "4"^^ . _:b376136196 . _:b376136801 . _:b376135472 "4"^^ . . _:b376136800 . _:b376135475 "4"^^ . _:b376136803 . _:b376135474 "4"^^ . . _:b376136802 . _:b376136433 . _:b376135485 "4"^^ . . _:b376136813 . _:b376135484 "4"^^ . . _:b376135327 . _:b376136812 . _:b376135487 "4"^^ . _:b376136759 . _:b376136815 . . _:b376135486 "4"^^ . . _:b376135248 . _:b376136814 . _:b376135481 "4"^^ . . _:b376136809 . _:b376135480 "4"^^ . . _:b376136808 . _:b376136800 . _:b376135483 "4"^^ . _:b376135999 . _:b376136205 . _:b376136811 . _:b376136225 . _:b376135482 "4"^^ . _:b376136555 . _:b376136810 . _:b376135493 "4"^^ . _:b376136442 . _:b376136821 . _:b376136345 . _:b376135492 "4"^^ . _:b376136512 . _:b376136820 . _:b376135495 "4"^^ . _:b376136318 . _:b376135817 . _:b376136823 . _:b376135494 "4"^^ . _:b376136822 . . _:b376135489 "4"^^ . . _:b376136817 . _:b376135808 . _:b376135488 "4"^^ . _:b376136816 . _:b376135491 "4"^^ . . _:b376135554 . _:b376136819 . _:b376135490 "4"^^ . _:b376136818 . _:b376135501 "4"^^ . _:b376136694 . _:b376136567 . _:b376136829 . . . _:b376135500 "4"^^ . _:b376136828 . _:b376135503 "4"^^ . . . _:b376136831 . _:b376135502 "4"^^ . . . _:b376136830 . . _:b376135497 "4"^^ . _:b376135635 . _:b376135279 . _:b376136825 . _:b376136091 . _:b376135496 "4"^^ . _:b376135699 . _:b376136824 . _:b376135499 "4"^^ . _:b376136827 . _:b376135498 "4"^^ . . . _:b376136826 . . _:b376135509 "4"^^ . . _:b376136837 . _:b376135508 "4"^^ . . _:b376136836 . _:b376136822 . _:b376135511 "4"^^ . _:b376135755 . _:b376135840 . . _:b376136839 . _:b376135510 "4"^^ . . _:b376136838 . _:b376135684 . _:b376135505 "4"^^ . _:b376136833 . _:b376136351 . _:b376135504 "4"^^ . _:b376136832 . _:b3471554 "In the host, many niches colonized by S. aureus are maintained in lower pH ranges, such as the skin and vaginal tract [>>26<<], colonization sites that repress agr function could promote biofilm formation." . . _:b376135507 "4"^^ . . _:b376136835 . _:b376135234 . . _:b3471572 "One potential target is the surface adhesins, and possible candidates include the surface proteins Atl, Bap, and SasG, all of which have reported roles in biofilm formation [41], [42], [>>71<<]\u2013[73]. Atl is additionally known to require proteolytic processing for activation, and this processing is PMSF inhibited [74]. Other possibilities include microbial surface components recognizing adhesive matrix molecules (MSCRAMMs), which" . _:b376135506 "4"^^ . _:b376136834 . . _:b376135517 "4"^^ . _:b376136845 . _:b376135516 "4"^^ . . _:b376136844 . _:b376135519 "4"^^ . _:b376135199 . _:b376136429 . _:b376136847 . _:b376135499 . . _:b376135518 "4"^^ . _:b376136752 . . _:b376136846 . _:b376136132 . _:b376135513 "4"^^ . _:b376136480 . _:b376136841 . _:b376135512 "4"^^ . _:b376136840 . . _:b376135515 "4"^^ . _:b376136320 . _:b376136843 . _:b376135514 "4"^^ . _:b376136842 . _:b376135525 "4"^^ . _:b3471469 "workAH750SH1000/\u0394aur \u0394spl::erm ErmThis workAH788AH750/pDB59Cam, ErmThis workAH789AH703/pDB59CamThis workAH860SH1000/\u0394spl::erm sspA::tet Erm, TetThis workAH861SH1001/pDB59+pAH9Cam, ErmThis workPlasmidspDB59P3-GFP reporterAmp, Cam [>>19<<] pAH9 sarA promoter P1-RFPAmp, ErmThis workpDNAB8-AIPIAIP-I intein plasmidAmp [27] pDNAB8-AIPIIAIP-II intein plasmidAmp [27] pDNAB8-AIPIIIAIP-III intein plasmidAmp [27] pKOR1-aur aur knockout vectorAmp, Cam [16] Construction of an RFP" . _:b376136853 . _:b376135524 "4"^^ . _:b376135309 . _:b376136852 . _:b376135527 "4"^^ . _:b376135526 "4"^^ . . . _:b376136854 . _:b376135521 "4"^^ . _:b376136400 . _:b376136849 . _:b376135520 "4"^^ . _:b3471482 "Interestingly, in most published flow cell biofilm studies, one commonality is the use of growth media containing or supplemented with glucose [9], [>>19<<], [21]\u2013[24]." . . _:b376136064 . _:b376136848 . _:b3471447 "gene regulator (agr) locus and the communication molecule that it produces and senses is called an autoinducing peptide (AIP), which is an eight-residue peptide with the last five residues constrained in a cyclic thiolactone ring [>>15<<]. During growth, AIP is synthesized and secreted through a poorly understood mechanism that requires multiple peptidases [16],[17]." . _:b376135523 "4"^^ . . _:b376135786 . _:b376136851 . _:b376135522 "4"^^ . _:b376136604 . _:b376136850 . _:b376135533 "4"^^ . _:b376135545 . _:b376136235 . _:b376135532 "4"^^ . _:b376135535 "4"^^ . _:b376135534 "4"^^ . _:b376135529 "4"^^ . _:b3471548 "These results are in accord with previous studies showing that agr mutants have a propensity to form biofilms [>>13<<],[14] and that cells actively expressing agr leave biofilms at a high frequency [19]." . _:b376135528 "4"^^ . . _:b376135531 "4"^^ . . _:b376135868 . _:b376135530 "4"^^ . _:b376135873 . _:b3471517 "Considering the agr system regulates the secreted proteases [45],[>>46<<], we hypothesized that increased expression of extracellular proteases could be responsible for biofilm detachment." . _:b376135541 "4"^^ . _:b376135540 "4"^^ . _:b376135543 "4"^^ . . . . _:b3471472 "The mCherry (RFP) gene was PCR amplified from pRSET-mCherry [>>86<<] with oligonucleotides incorporating a 5\u2032 ribosome binding site and KpnI site and a 3\u2032 EcoRI site (for 5\u2032-GTTGGTACCTAGGGAGGTTTTAAACATGGTGAGCAAGGGCGAGGAGG-3\u2032, rev 5\u2032-GTTGAATTCTTACTTGTACAGCTCGTCCATGCC-3\u2032)." . _:b376135542 "4"^^ . . _:b376135537 "4"^^ . _:b376135553 . _:b376135236 . _:b376135536 "4"^^ . . . _:b376135539 "4"^^ . _:b376136672 . _:b376135538 "4"^^ . _:b376135549 "4"^^ . _:b376135548 "4"^^ . _:b376135301 . . . _:b3471480 . _:b376135551 "4"^^ . . _:b376135550 "4"^^ . . _:b376135545 "4"^^ . _:b376135381 . _:b376135544 "4"^^ . . _:b376135532 . _:b376135547 "4"^^ . . . _:b376135546 "4"^^ . . _:b376135557 "4"^^ . _:b3471487 . . . _:b376135556 "4"^^ . _:b376135899 . _:b376135559 "4"^^ . _:b376135558 "4"^^ . _:b376135768 . _:b376135457 . _:b376135553 "4"^^ . . . _:b376136017 . _:b376135993 . _:b376135552 "4"^^ . _:b3471544 "Alternatively, detachment studies have addressed effector gene products that contribute to the dissolution of the biofilm, including surfactants [10],[13],[64],[65], hydrolases [66],[>>67<<], proteases [37]\u2013[39], and DNase [68]." . _:b376135555 "4"^^ . _:b376135239 . _:b376135554 "4"^^ . _:b376135603 . _:b376135565 "4"^^ . _:b376135329 . _:b376135564 "4"^^ . . _:b376135391 . . . _:b376135567 "4"^^ . _:b376135566 "4"^^ . . _:b376136336 . _:b376135600 . _:b376135461 . _:b376135561 "4"^^ . . _:b376135564 . _:b376135560 "4"^^ . _:b376136630 . _:b376135776 . . _:b376135563 "4"^^ . _:b376135450 . . _:b376135562 "4"^^ . . . _:b376136124 . _:b376135573 "4"^^ . _:b376135572 "4"^^ . _:b376135575 "4"^^ . . _:b376135574 "4"^^ . _:b376135569 "4"^^ . _:b376135969 . _:b376136713 . _:b376135568 "4"^^ . . _:b376136599 . _:b376135571 "4"^^ . . _:b376136778 . . _:b376135570 "4"^^ . . _:b376135393 . _:b376135581 "4"^^ . _:b376135580 "4"^^ . . . . _:b376135583 "4"^^ . _:b376135582 "4"^^ . . _:b376135914 . . _:b376135577 "4"^^ . . . _:b376135576 "4"^^ . _:b376135579 "4"^^ . _:b376136847 . _:b376136406 . _:b3471448 . _:b376136498 . . _:b376135578 "4"^^ . . . _:b376135589 "4"^^ . . _:b376135588 "4"^^ . . . _:b376135591 "4"^^ . . _:b376135590 "4"^^ . . . _:b376135585 "4"^^ . . . _:b376136627 . _:b376135584 "4"^^ . . . _:b376135587 "4"^^ . _:b376135586 "4"^^ . _:b376136731 . . . _:b376135597 "3"^^ . _:b376135596 "3"^^ . _:b376135599 "3"^^ . . _:b376135598 "3"^^ . _:b376135593 "3"^^ . _:b376135630 . _:b376135398 . _:b376135592 "3"^^ . _:b376136102 . _:b376135595 "3"^^ . . _:b376135791 . _:b376136157 . _:b376135594 "3"^^ . . _:b376135605 "3"^^ . _:b376136181 . _:b3471470 . . . _:b376135604 "3"^^ . . _:b376135607 "3"^^ . _:b376136607 . . _:b3471468 . . _:b376136259 . _:b376135606 "3"^^ . _:b376136848 . _:b376135601 "3"^^ . _:b3471458 . _:b376135600 "3"^^ . _:b376135901 . _:b376135603 "3"^^ . _:b376135299 . _:b376135602 "3"^^ . _:b376135613 "3"^^ . . . _:b376135612 "3"^^ . _:b376135197 . _:b376135615 "3"^^ . . . _:b376135614 "3"^^ . . . . _:b376135609 "3"^^ . _:b376135608 "3"^^ . _:b376136439 . _:b376135611 "3"^^ . _:b376136407 . _:b376135387 . _:b376135610 "3"^^ . . . _:b376136305 . _:b376135843 . _:b376135957 . _:b376135621 "3"^^ . . _:b376135620 "3"^^ . . _:b376135623 "3"^^ . _:b376135297 . _:b376135622 "3"^^ . . _:b376135617 "3"^^ . _:b376135616 "3"^^ . . _:b376135619 "3"^^ . . _:b376135618 "3"^^ . . _:b376135638 . . _:b376135629 "3"^^ . . _:b376135628 "3"^^ . . _:b376135631 "3"^^ . _:b376135372 . _:b376135630 "3"^^ . _:b376135676 . _:b376135625 "3"^^ . _:b376135624 "3"^^ . _:b376135627 "3"^^ . _:b376135866 . . _:b376135626 "3"^^ . _:b376135637 "3"^^ . . _:b376136453 . _:b376135636 "3"^^ . _:b376136452 . _:b376135639 "3"^^ . . _:b376135353 . . _:b376135558 . _:b376136455 . _:b376135638 "3"^^ . _:b3471553 . _:b376136506 . _:b376135343 . _:b376136454 . _:b376135633 "3"^^ . _:b376136449 . _:b376135632 "3"^^ . _:b376136284 . _:b376136448 . _:b376135609 . _:b376135635 "3"^^ . _:b376136451 . _:b376135634 "3"^^ . _:b376136450 . _:b376135645 "3"^^ . . . _:b376136461 . _:b376135644 "3"^^ . _:b376136204 . _:b376136205 . _:b376136206 . _:b376136460 . _:b376136207 . _:b376135647 "3"^^ . _:b376136200 . _:b376136201 . _:b376136202 . _:b376136463 . _:b376136203 . _:b376135646 "3"^^ . _:b376136196 . _:b376136197 . _:b376136198 . _:b3471444 "Studies on the opportunistic pathogen Pseudomonas aeruginosa indicate that cell-to-cell communication (often termed \u201Cquorum-sensing\u201D) is required to make a robust biofilm under some growth conditions [>>12<<]. Surprisingly, the opposite is true in S. aureus, as the presence of an active quorum-sensing impedes attachment and development of a biofilm [13],[14]." . _:b376136462 . _:b376136199 . _:b376135641 "3"^^ . _:b376136192 . . _:b376136193 . _:b376136194 . _:b376136457 . _:b376136195 . _:b376135640 "3"^^ . _:b376136220 . _:b376136481 . _:b376136353 . _:b376136221 . _:b376135788 . _:b376136222 . _:b376136456 . _:b376136223 . _:b376135643 "3"^^ . _:b376136216 . _:b376136217 . _:b376136218 . _:b376136459 . _:b376136219 . _:b376135642 "3"^^ . _:b376136212 . _:b376136213 . _:b3471528 . _:b376136582 . . _:b376136214 . _:b376136458 . _:b376136215 . . _:b376135653 "3"^^ . _:b376136208 . _:b376136209 . _:b376136210 . _:b376136469 . _:b376136211 . _:b376135652 "3"^^ . _:b376136236 . _:b376136237 . _:b376136363 . _:b376136238 . _:b376136468 . _:b376136239 . _:b376135655 "3"^^ . _:b376136232 . _:b376136233 . _:b376136234 . _:b376136471 . _:b376136235 . _:b376135654 "3"^^ . _:b376136228 . _:b376136229 . _:b376135952 . _:b376136230 . _:b376136470 . _:b376136231 . . _:b376135649 "3"^^ . _:b376136224 . _:b376136225 . _:b376136493 . _:b376136226 . _:b376136465 . _:b376136227 . _:b376135648 "3"^^ . _:b376136252 . _:b376135455 . _:b376136253 . _:b376136167 . _:b376136254 . _:b376136464 . _:b376136255 . _:b376135651 "3"^^ . _:b376136248 . _:b376136249 . _:b376136250 . _:b376136467 . _:b376136251 . _:b376135650 "3"^^ . _:b376136244 . _:b376136245 . _:b376136246 . _:b376136466 . _:b376136247 . _:b376136768 . _:b376135661 "3"^^ . _:b376136240 . _:b376136241 . . _:b376136242 . _:b376136477 . . . _:b376136243 . _:b376135660 "3"^^ . _:b376136268 . _:b376136269 . _:b376136270 . _:b376136476 . _:b376136271 . _:b376136371 . _:b376135663 "3"^^ . _:b376136264 . _:b376136265 . _:b376136266 . _:b376136479 . _:b376136142 . _:b376136267 . _:b376135662 "3"^^ . _:b376136260 . . _:b376136261 . _:b3471524 . _:b376136262 . _:b376136478 . _:b376136263 . _:b376135657 "3"^^ . _:b376136256 . . _:b376136257 . . _:b376136258 . _:b376136473 . _:b376136259 . _:b376135656 "3"^^ . _:b376136284 . _:b376136285 . _:b376136286 . _:b376136472 . _:b376136287 . _:b376136451 . _:b376135659 "3"^^ . _:b376136280 . _:b376136281 . _:b376136282 . _:b376136475 . _:b376136283 . _:b376136086 . _:b376135658 "3"^^ . _:b376136276 . _:b376136277 . . . _:b376136278 . _:b376136474 . . _:b376136279 . _:b376135669 "3"^^ . _:b376136272 . . _:b376136273 . _:b376136274 . _:b376136509 . _:b376136485 . _:b376136275 . _:b376135668 "3"^^ . _:b376136300 . _:b376136301 . _:b376136302 . _:b376136484 . _:b376136303 . _:b376135671 "3"^^ . _:b376136296 . _:b376136297 . _:b376136298 . _:b376136487 . _:b376136299 . _:b376135670 "3"^^ . _:b376136292 . . _:b376136293 . _:b3471558 . _:b376136294 . _:b376136486 . _:b376136306 . _:b376136295 . _:b376135665 "3"^^ . _:b376135877 . _:b376136288 . _:b376136289 . . . _:b376136290 . _:b376136481 . . . _:b376136291 . _:b376135664 "3"^^ . _:b376136316 . _:b376136317 . . . _:b376136318 . _:b376136480 . _:b376136319 . . _:b376135667 "3"^^ . . . _:b376136312 . . _:b376135827 . _:b376136313 . _:b376136314 . _:b376136483 . _:b376136315 . _:b376135666 "3"^^ . _:b376136308 . _:b376136309 . _:b376136310 . _:b376136482 . _:b376136311 . _:b376135677 "3"^^ . _:b376135522 . _:b376136304 . _:b376136305 . _:b376136306 . _:b376136493 . _:b376136307 . _:b376135676 "3"^^ . _:b376136332 . _:b376136333 . _:b376136334 . _:b376136492 . _:b376136335 . _:b376135679 "3"^^ . _:b376136328 . _:b376136329 . . _:b376136330 . _:b376136495 . _:b376136331 . _:b376136050 . _:b376135678 "3"^^ . _:b376136324 . . _:b376136325 . _:b376136326 . _:b376136494 . _:b376136432 . . _:b376136327 . _:b376135673 "3"^^ . _:b376136320 . _:b376135368 . _:b376136321 . _:b376136322 . _:b376136489 . . _:b376135672 "3"^^ . _:b376136323 . _:b376136348 . _:b376136349 . . _:b376136350 . _:b376136488 . _:b376136351 . _:b376135675 "3"^^ . _:b376136344 . _:b376135209 . _:b376136345 . . _:b376136346 . _:b376136491 . . _:b376136347 . _:b376135674 "3"^^ . _:b376136340 . _:b376136341 . _:b376136342 . _:b376136490 . _:b376135515 . _:b376136343 . _:b376136336 . _:b376136566 . _:b376136337 . _:b376136338 . _:b376136501 . _:b376136339 . _:b376136364 . _:b376136365 . _:b376136366 . _:b376136500 . _:b376136460 . _:b376136367 . _:b376135979 . _:b376136360 . _:b376136361 . _:b376136362 . _:b376136771 . _:b376136503 . _:b376136363 . _:b376136356 . . _:b376136357 . _:b376136795 . _:b376136358 . _:b376136502 . _:b376136359 . _:b376136352 . . _:b376136353 . _:b376136354 . _:b376136497 . _:b376136355 . _:b376136380 . _:b376136381 . _:b376136382 . _:b376136496 . _:b376136383 . _:b376136376 . _:b376135359 . _:b376136377 . _:b376136378 . _:b376136499 . _:b376136379 . _:b376136372 . _:b376136373 . _:b376136374 . _:b376136498 . . _:b376136375 . . _:b376136368 . _:b376136369 . _:b376136370 . _:b376136509 . . _:b376136371 . _:b376136396 . _:b376136397 . _:b376136398 . _:b376136508 . _:b376136399 . _:b376136611 . _:b376136392 . _:b376135535 . _:b376136393 . _:b376135479 . _:b376136511 . . _:b376135346 . _:b376136394 . _:b376136395 . _:b376135806 . . _:b376136388 . _:b376136092 . _:b376136389 . _:b376136390 . _:b376136510 . _:b376136391 . _:b376135589 . _:b376136384 . . _:b376136385 . _:b376136386 . _:b376136505 . _:b376136387 . _:b376135402 . _:b376136717 . _:b376136412 . _:b376136413 . _:b376136414 . _:b376136504 . . _:b376136415 . _:b376136408 . _:b376136183 . _:b376136409 . _:b376136410 . _:b376136507 . _:b376135933 . _:b376136411 . _:b376136404 . _:b376136405 . _:b376136406 . _:b376136506 . _:b376136407 . _:b376136400 . . . . _:b376136401 . _:b376136402 . _:b376136517 . _:b376136403 . _:b376136457 . _:b376136428 . _:b376136429 . . _:b376136430 . _:b376136516 . _:b376136431 . _:b376136424 . _:b376136425 . _:b376136426 . _:b376136519 . _:b376136427 . _:b3471489 . _:b376136420 . _:b376136421 . _:b376136422 . _:b376136518 . _:b376136423 . _:b376136131 . . _:b376136416 . . _:b376136417 . . _:b376136513 . . _:b376136418 . _:b376136419 . _:b376136466 . _:b376136444 . _:b376136445 . _:b376136446 . _:b376136512 . _:b376136447 . _:b376136440 . _:b376136441 . _:b376135432 . _:b376136442 . _:b376136515 . _:b376136443 . . _:b376136436 . _:b376136437 . _:b376136438 . _:b376136514 . _:b376136439 . . _:b376136432 . _:b376136433 . _:b376136434 . _:b376136525 . _:b376136435 . _:b376136460 . _:b376136461 . _:b376136462 . _:b376136524 . _:b376136463 . _:b376136456 . _:b376136457 . _:b376136458 . _:b376136527 . _:b376136459 . _:b376136452 . _:b376136453 . . _:b376136454 . _:b376136526 . . _:b376136455 . _:b376136448 . _:b376136449 . _:b376136450 . _:b376136521 . _:b376136082 . . _:b376136451 . _:b376136476 . _:b376136477 . _:b376136478 . _:b376136689 . _:b376136520 . . _:b376136479 . _:b376136472 . _:b376136473 . _:b376136474 . _:b376136523 . _:b376136327 . _:b376136475 . . _:b376136468 . _:b376136469 . _:b376136448 . _:b376136470 . _:b376136522 . . _:b376136471 . _:b376136464 . _:b376136465 . _:b3471549 "These results are in accord with previous studies showing that agr mutants have a propensity to form biofilms [13],[>>14<<] and that cells actively expressing agr leave biofilms at a high frequency [19]. Our findings also explain why S. aureus biofilm formation requires glucose supplementation to growth media." . _:b376136466 . _:b376136533 . _:b376136467 . _:b376136492 . _:b376136571 . _:b376136493 . _:b376136494 . _:b376136532 . _:b376136495 . _:b376136488 . _:b376136489 . _:b376136490 . _:b376136535 . _:b376136491 . _:b376136572 . _:b376136465 . _:b376136484 . _:b376136485 . _:b376136486 . _:b376136534 . . _:b376136487 . _:b376136480 . _:b376136481 . _:b3471551 "The presence of glucose is known to represses RNAIII through a nonmaintained pH decrease to \u223C5.5 [>>20<<], resulting from the secretion of acidic metabolites." . _:b376136482 . _:b376136529 . _:b376136483 . _:b376136508 . _:b376136509 . _:b376136510 . _:b376136588 . _:b376136528 . _:b376136056 . _:b376136511 . _:b376136504 . _:b376136505 . _:b376136506 . _:b376136531 . _:b376136507 . _:b376136500 . _:b376136501 . _:b376136502 . _:b376136530 . _:b376136503 . _:b376136496 . _:b376136213 . _:b376136497 . _:b376136244 . _:b376136498 . _:b376136664 . _:b376136541 . _:b376136499 . _:b376136524 . _:b376136525 . _:b376136526 . _:b376136634 . _:b376136540 . _:b376136527 . _:b376135886 . . _:b376136520 . _:b376136521 . _:b376136522 . _:b376136543 . _:b376136523 . . _:b376135590 . _:b376136516 . _:b376136517 . _:b376136518 . _:b376136542 . . _:b376136519 . _:b376136512 . _:b376136513 . _:b376136514 . _:b376136537 . _:b376136515 . _:b376136540 . _:b376136541 . _:b376136542 . _:b376136536 . . _:b376136543 . _:b376136536 . _:b376136537 . _:b376136538 . _:b376136539 . _:b376136539 . _:b376136532 . _:b3471493 "Since AIP-I and AIP-IV differ by only one amino acid and function interchangeably [28], they are grouped together in the classification scheme, although this assignment has been controversial [29],[>>30<<]." . _:b376136533 . _:b376136534 . _:b376136538 . _:b376136302 . _:b376136535 . _:b376136528 . _:b376136529 . _:b376136530 . _:b376136549 . _:b376136531 . _:b376136556 . _:b376136557 . . _:b376136558 . _:b376136548 . _:b376136559 . _:b376136552 . . _:b376136553 . _:b376136554 . _:b376136551 . _:b376136555 . _:b376136548 . . _:b376136549 . _:b376136550 . _:b376136550 . _:b376136551 . . _:b376136544 . _:b376136545 . _:b376136546 . _:b376136545 . _:b376136547 . _:b376136572 . _:b376136573 . . _:b376136574 . _:b376136544 . _:b376136575 . _:b376136568 . _:b376136569 . _:b376136570 . _:b376136547 . . _:b376136571 . _:b376136399 . _:b376136564 . _:b376136565 . _:b376136566 . _:b376136546 . _:b376136027 . _:b376136567 . _:b376136560 . _:b376136561 . . _:b376136562 . _:b376136557 . _:b376136563 . _:b376136588 . _:b376136589 . _:b376136590 . _:b376136556 . _:b376136591 . _:b376136584 . _:b376136540 . _:b376136585 . _:b376136586 . _:b376136559 . _:b376136587 . _:b376136580 . _:b376136581 . _:b376136128 . _:b376136582 . _:b376136558 . . _:b376136583 . _:b376136746 . _:b376136576 . _:b376136577 . _:b376136578 . _:b376136553 . _:b376136579 . _:b376136604 . . _:b376136605 . _:b376136606 . _:b376136552 . _:b376136607 . . _:b376136600 . _:b376136601 . _:b376136602 . _:b376136555 . _:b376136603 . . _:b376136596 . _:b376136708 . _:b376136005 . . _:b376136597 . . _:b376136598 . _:b376136554 . _:b376136599 . _:b376136592 . _:b376136593 . _:b376136594 . _:b376136565 . _:b376135694 . _:b376136595 . _:b3471551 . . _:b376136620 . _:b376136621 . _:b376136622 . _:b376136564 . _:b376136623 . _:b376135306 . _:b376136616 . . _:b376136617 . _:b376136618 . _:b376136567 . _:b376136619 . . _:b376136612 . _:b376136613 . _:b376136614 . _:b376136566 . . _:b376136615 . _:b3471560 "detachment has been observed in response to changing environmental conditions, such as oxygen levels [57],[69], nutrient depletion [54], changing nutrient composition [55], or increased concentration of quorum-sensing signals [>>61<<]. An S. aureus biofilm growing in vivo is likely to encounter a changing physiochemical environment, which could serve as a cue to induce accelerated detachment through an agr-mediated mechanism." . _:b376135614 . _:b376136608 . _:b376136609 . _:b376136610 . _:b376136561 . _:b376136611 . _:b376136636 . _:b376136637 . _:b376136638 . _:b376136560 . _:b376136639 . _:b376136632 . _:b376136633 . . _:b376136634 . _:b3471440 . _:b376136563 . . _:b376136635 . _:b376136628 . _:b376136629 . _:b376136630 . _:b376136562 . _:b376136631 . _:b376136624 . _:b376136625 . _:b3471531 . _:b376136626 . _:b376136573 . _:b376136627 . _:b3471577 . _:b376136652 . _:b376136653 . _:b376136654 . _:b3471567 "material is important for SH1000 biofilm integrity, and this result supports a number of recent studies demonstrating that proteases can inhibit biofilm formation or detach established biofilms from many S. aureus strains [35], [37]\u2013[>>39<<]. It is not clear whether agr-mediated detachment will function in S. aureus strains that produce an ica-dependent biofilm." . _:b376136572 . . _:b376136655 . _:b376136648 . _:b376136649 . _:b376136650 . _:b376136575 . _:b376136651 . . _:b376136644 . _:b376136384 . _:b376136645 . _:b376136646 . _:b376136796 . _:b376136574 . . . _:b376135862 . _:b376136647 . _:b376136790 . . . _:b376136640 . _:b376136641 . . _:b376136642 . _:b376136569 . _:b376136643 . _:b376136668 . _:b376136669 . _:b376136670 . _:b376136568 . _:b376135447 . _:b376136671 . _:b376136664 . . _:b376136665 . _:b376136666 . _:b376136571 . . _:b376136667 . _:b376136660 . _:b376136661 . _:b376136662 . _:b376136570 . _:b376136663 . _:b376136656 . . _:b376136657 . _:b376136658 . _:b376136581 . _:b376136659 . _:b376136715 . _:b376135875 . . _:b376136684 . _:b376136685 . _:b376136686 . _:b376136580 . _:b376136687 . _:b376135316 . _:b376136680 . _:b376136681 . _:b376136657 . _:b376136682 . _:b376136583 . _:b376135485 . _:b376136683 . . _:b376136676 . _:b376135191 . _:b376135394 . _:b376136677 . _:b376136678 . _:b376136582 . _:b376136679 . _:b376136672 . . _:b376136673 . _:b376136674 . _:b376136577 . _:b376136675 . _:b376135704 . _:b376136700 . _:b376136701 . _:b376136702 . _:b376136576 . _:b376136703 . _:b376136696 . _:b376136697 . _:b376136698 . _:b376136579 . _:b376136699 . _:b376136692 . _:b376136693 . _:b376136625 . _:b376136694 . _:b376136578 . _:b376136695 . _:b376136688 . _:b376136614 . _:b376136689 . _:b376136355 . _:b376136690 . _:b376136589 . _:b376135470 . _:b376136691 . _:b376135692 . _:b376135429 . _:b376135693 . _:b376135694 . _:b376136588 . _:b376135695 . _:b376135688 . _:b376135428 . _:b376135689 . _:b376135690 . _:b376136591 . _:b376135691 . _:b376135684 . _:b376135431 . _:b376135685 . . _:b376135686 . _:b376136590 . _:b376135687 . _:b376135680 . _:b376135430 . _:b376135400 . _:b376135681 . _:b376135682 . _:b376136585 . _:b376135683 . _:b376135708 . _:b376135425 . . . _:b376135709 . _:b376135710 . _:b376136584 . . _:b376135711 . . _:b376135704 . _:b376135424 . _:b376135434 . _:b376135705 . _:b376135706 . _:b376136587 . . . _:b376135707 . _:b376135700 . _:b376136693 . _:b376135427 . _:b376135701 . _:b376135702 . _:b376136586 . _:b376135703 . . _:b376135696 . _:b376136088 . _:b376135426 . _:b376135628 . . _:b376135697 . _:b376135698 . _:b376136597 . _:b376135699 . _:b376135442 . _:b376135772 . _:b376135724 . _:b376135437 . _:b376135725 . _:b376135726 . _:b376136596 . _:b376135727 . _:b376135720 . _:b376135436 . _:b376135721 . _:b376135722 . _:b376136599 . _:b376135723 . _:b376135716 . _:b376135439 . _:b376135717 . _:b376135718 . _:b376136598 . _:b376135719 . _:b376135712 . _:b376135438 . _:b376135713 . _:b376135714 . _:b376136593 . _:b376135715 . _:b376135740 . _:b376135433 . _:b376135741 . _:b376135742 . _:b376136592 . _:b376135743 . _:b376135736 . _:b376135432 . _:b376135737 . _:b376135961 . . _:b376135738 . _:b376136595 . . _:b376135276 . . _:b376135739 . _:b376135732 . _:b376136575 . _:b376135435 . . _:b376135733 . _:b376135734 . _:b376136594 . _:b376135735 . _:b376135728 . _:b376135434 . _:b376135729 . _:b376135446 . _:b376135730 . _:b376136605 . _:b376135731 . . _:b376135935 . _:b376135584 . _:b376135445 . _:b376135756 . _:b376135757 . _:b376135758 . _:b376136604 . _:b376135759 . _:b376135752 . _:b376135444 . _:b376135753 . _:b376135754 . _:b376136607 . . _:b376135755 . . _:b376136020 . _:b376135447 . _:b376135748 . _:b376135749 . _:b3471455 . _:b376135750 . _:b376136606 . _:b376135751 . _:b376135744 . _:b376135446 . _:b376135745 . _:b376135746 . _:b376136601 . _:b376135747 . _:b376135772 . _:b376135441 . . _:b376135773 . _:b376135774 . _:b376136600 . _:b376135598 . _:b376135775 . _:b376135768 . _:b376135440 . . _:b376135769 . _:b3471443 "In response to certain environmental cues, bacteria living in biofilms are capable of using active mechanisms to leave biofilms and return to the planktonic (free-living) state in which sensitivity to antimicrobials is regained [9]\u2013[>>11<<]. Therefore an improved understanding of the molecular mechanism of biofilm detachment could facilitate the discovery of innovative treatment options." . _:b376135616 . . _:b376136603 . _:b376135770 . _:b376135771 . _:b376135764 . _:b376136341 . _:b376135443 . _:b376135765 . _:b376135766 . _:b376136602 . _:b376135767 . _:b376135760 . _:b376135442 . . _:b376135761 . _:b376135762 . _:b376136613 . _:b376135523 . . _:b376135763 . _:b376135788 . _:b3471520 "There are 10 known extracellular proteases produced by most S. aureus strains and expression of all these enzymes is controlled by the agr system [18],[45],[>>46<<]. These 10 proteases include the metalloprotease aureolysin (aur), two cysteine proteases (scpA and sspB), and seven serine proteases (sspA (V8) and splABCDEF) [47]." . _:b376136758 . _:b376135453 . _:b376135789 . _:b3471559 . _:b376136431 . _:b376135790 . _:b376136612 . . . _:b376135791 . _:b376135784 . _:b376135314 . _:b376135452 . _:b376135785 . _:b376135786 . _:b376136615 . _:b376135787 . _:b3471456 "Plasmids were moved from RN4220 into other S. aureus strains by transduction with bacteriophage \u03B180 [>>85<<] or by purifying the plasmid DNA and transformed by electroporation into appropriate strains." . _:b376136646 . _:b376135780 . _:b376136579 . _:b376135455 . _:b376135781 . _:b376135782 . _:b376136614 . . _:b376135783 . _:b376135324 . _:b376135776 . _:b376135444 . . _:b376135454 . _:b376135777 . _:b376135778 . _:b376136609 . _:b376135779 . . _:b376135804 . _:b376135449 . _:b376135805 . _:b376135806 . _:b376136608 . _:b376135807 . _:b376135800 . _:b376135448 . _:b376135801 . _:b376135802 . _:b376136611 . _:b376135803 . _:b376135796 . _:b376135451 . _:b376135797 . _:b376135798 . _:b376136610 . _:b376135799 . _:b376135792 . _:b376135483 . _:b376135450 . _:b376135793 . _:b376135794 . _:b376136621 . _:b376135194 . _:b376135795 . _:b376135820 . _:b376135461 . _:b376135821 . _:b376135769 . _:b376135822 . _:b376136620 . _:b376135823 . _:b3471533 "The majority of studies on biofilm detachment have focused on factors capable of initiating the process, such as nutrient availability [54],[55], nitric oxide exposure [>>56<<], oxygen tension [57], iron salts [58], chelators [59], and signaling molecules [60]\u2013[63]." . _:b376135816 . _:b376135460 . _:b376135817 . _:b376135818 . _:b376136623 . _:b376135819 . _:b376135812 . _:b376135463 . _:b376135813 . _:b376135814 . _:b376136622 . _:b376135815 . _:b376135808 . _:b376136014 . _:b376135462 . _:b376135809 . _:b376135810 . _:b376136617 . . _:b376135811 . _:b376135836 . . _:b376135457 . _:b376135837 . _:b376135838 . _:b376136616 . _:b376135330 . _:b376135839 . _:b376135832 . _:b376135456 . _:b376135833 . _:b376135834 . _:b376136619 . _:b376136405 . _:b376135835 . _:b376135828 . _:b376135459 . _:b376135829 . _:b376135830 . _:b376136618 . _:b376135831 . _:b376135824 . _:b376135458 . . _:b376135825 . _:b376135826 . _:b376136629 . _:b376135827 . _:b376135852 . _:b376135469 . _:b376135853 . _:b376135854 . _:b376136628 . _:b376135855 . _:b3471590 "However, homoserine lactone signals play a divergent role in Pseudomonas aeuruginosa [12], Pseudomonas fluorescens [>>82<<], and Burkholderia cepacia [83], where the active versions of these quorum-sensing systems are necessary for biofilm formation and robustness under some growth conditions." . _:b376135848 . _:b376135468 . . _:b376135849 . _:b376135850 . _:b376136631 . _:b376135382 . _:b376135851 . _:b3471476 . _:b376136554 . _:b376135844 . _:b376135471 . _:b376135845 . _:b376136398 . _:b376135846 . _:b376136630 . _:b376135854 . _:b376135847 . _:b3471542 "Alternatively, detachment studies have addressed effector gene products that contribute to the dissolution of the biofilm, including surfactants [10],[13],[64],[>>65<<], hydrolases [66],[67], proteases [37]\u2013[39], and DNase [68]." . _:b376135840 . _:b376135470 . _:b376135841 . _:b376135842 . _:b376136625 . _:b376135843 . _:b376135868 . _:b376135465 . _:b376135869 . _:b376135870 . _:b376136624 . _:b376136556 . _:b376135871 . _:b376135864 . _:b376135464 . _:b376135865 . _:b376135866 . _:b376136627 . _:b376135867 . _:b376135860 . _:b376135467 . _:b376135861 . _:b376135862 . _:b376136626 . _:b376135863 . _:b376135856 . _:b376135466 . _:b376135857 . _:b376135858 . _:b376136637 . _:b376135859 . _:b376135884 . _:b376135477 . _:b376135885 . _:b376135886 . _:b376136636 . _:b376135887 . _:b376135880 . _:b376135476 . . _:b376135881 . _:b376135882 . _:b376136639 . _:b376135362 . _:b376135883 . _:b376135876 . _:b376135479 . _:b376135877 . _:b376135878 . _:b376136638 . . _:b376135879 . _:b376135872 . _:b376135478 . _:b376135232 . _:b376135873 . _:b376135874 . _:b376136633 . . _:b376135875 . _:b376135900 . _:b376135473 . _:b376135901 . _:b376135902 . _:b376136632 . _:b376136392 . _:b376135903 . _:b376135896 . _:b376135472 . _:b376135897 . _:b376135898 . _:b376136635 . _:b376135899 . _:b376136315 . . _:b376135475 . _:b376135892 . _:b376135893 . _:b376135894 . _:b376136634 . . _:b376135895 . _:b376135925 . . _:b376135888 . _:b3471453 "These findings correlate well with prior data indicating that agr deficient S. aureus strains form more robust biofilms compared to wild type strains [13],[>>14<<]." . _:b376135474 . _:b376135889 . . _:b376135890 . _:b376136645 . _:b376135891 . _:b376135916 . _:b376135485 . _:b376135917 . _:b376135918 . _:b376136644 . . _:b376135919 . . _:b376135912 . _:b376135484 . _:b376135913 . _:b376135914 . _:b376136647 . _:b376135915 . _:b376135908 . _:b376135487 . _:b376135909 . _:b376135910 . _:b376136646 . _:b376135911 . _:b376135612 . _:b376135904 . _:b376135486 . _:b376135905 . _:b376135906 . _:b376136641 . _:b376135907 . _:b376135932 . _:b376135481 . _:b376135933 . _:b376135934 . _:b376136640 . _:b376135935 . _:b376135928 . _:b376135480 . _:b376135900 . _:b376135929 . _:b376135930 . _:b376136643 . _:b376135931 . . _:b376135924 . _:b376135483 . _:b376135925 . _:b376135926 . _:b376136642 . _:b376135927 . _:b376136097 . _:b376135920 . _:b376135482 . _:b376135921 . _:b376136094 . _:b376135922 . _:b376136653 . _:b376135923 . _:b376135948 . _:b376136645 . _:b376135493 . _:b376135949 . _:b376136490 . _:b376135950 . _:b376136652 . _:b376135951 . _:b376135944 . _:b376135492 . _:b376135945 . _:b376135946 . _:b376136655 . _:b376135947 . _:b376135940 . _:b376135495 . _:b376135941 . _:b376135942 . _:b3471520 . _:b376136654 . _:b376135943 . _:b376135936 . _:b376135494 . _:b376135937 . _:b376135938 . _:b376136649 . . _:b376135939 . _:b376135964 . _:b376135489 . _:b376135965 . _:b376135966 . _:b376136648 . _:b376136099 . _:b376135967 . _:b376135960 . _:b376135488 . _:b376135961 . _:b376135962 . _:b376136651 . _:b376135963 . _:b376135956 . _:b376135491 . _:b376135957 . _:b376135958 . _:b376136650 . _:b376135959 . _:b376135952 . _:b376135490 . . _:b376135953 . _:b376135954 . _:b376136661 . _:b376136390 . _:b376136270 . _:b376135955 . _:b376135980 . _:b376135501 . _:b376135981 . _:b376135982 . _:b376136660 . _:b376135983 . . _:b376135976 . _:b376136736 . _:b376135500 . _:b376135977 . _:b376135978 . _:b376136663 . _:b376135979 . _:b376135972 . _:b376135503 . _:b376135973 . _:b376135974 . _:b376136662 . _:b376135975 . _:b376135968 . _:b376135502 . _:b376135969 . _:b376135970 . _:b376136657 . _:b376135971 . _:b376135996 . _:b376135497 . _:b376135997 . _:b376135998 . _:b376136656 . . _:b376135999 . _:b376135992 . _:b376135496 . _:b376135993 . _:b376135994 . _:b376136659 . _:b376135995 . _:b376135988 . _:b376135499 . _:b376135989 . _:b376135990 . _:b376136658 . _:b376135991 . _:b376135984 . _:b376135498 . _:b376135985 . _:b376135986 . _:b376136669 . _:b376135987 . _:b376136012 . _:b376135509 . _:b376136013 . _:b376136006 . _:b376136014 . _:b376136668 . _:b376136015 . _:b376136296 . . _:b376136008 . _:b376135508 . _:b376136009 . _:b376135465 . _:b376136010 . _:b376136671 . . . _:b376136011 . _:b376136004 . _:b376135511 . _:b376136005 . _:b376136006 . _:b376136670 . _:b376136007 . . _:b376135225 . _:b376136000 . _:b376135510 . . _:b376136001 . _:b376136002 . _:b376136665 . _:b376136003 . _:b376136028 . . _:b376135505 . _:b376136029 . _:b376136030 . _:b376136664 . _:b376136031 . _:b376136024 . _:b376135504 . _:b376136025 . _:b376136026 . _:b376136667 . . . _:b376136027 . _:b376136020 . _:b376135507 . _:b376136021 . _:b376135998 . _:b376136022 . _:b376136666 . _:b376136023 . . _:b376135506 . _:b376136016 . _:b376136017 . _:b376136018 . _:b376136677 . _:b376136019 . _:b376136378 . _:b376136044 . _:b376135517 . _:b376136045 . _:b3471474 . _:b376136046 . _:b376136676 . _:b376136047 . _:b376136040 . _:b376135516 . _:b376136041 . _:b376136042 . _:b376136679 . _:b376136043 . _:b376136036 . _:b376135519 . _:b376136037 . . _:b376136038 . _:b376136678 . _:b376136039 . . _:b376135518 . _:b376136032 . _:b376136033 . _:b376136034 . _:b376136673 . _:b376136035 . _:b376136060 . _:b376135513 . . _:b376136061 . _:b376136062 . _:b376136672 . _:b376136063 . _:b376136056 . _:b376135512 . _:b376136057 . _:b376136058 . _:b376136675 . _:b376136059 . _:b376136052 . _:b376135515 . _:b376136053 . _:b376136054 . _:b376136674 . . _:b376136055 . _:b376136048 . _:b376135514 . _:b376136049 . _:b376136050 . _:b376136685 . _:b376136051 . _:b376136076 . _:b376135525 . _:b376136077 . _:b376136078 . _:b376136684 . _:b376136079 . _:b376136072 . _:b376136216 . _:b376135524 . _:b376136073 . _:b376136074 . _:b376136712 . _:b376136687 . _:b376136075 . _:b376136068 . _:b376135527 . _:b376135383 . _:b376136069 . _:b376136070 . _:b376136686 . _:b376136071 . _:b376136064 . _:b376135526 . _:b376136065 . _:b376136066 . _:b376136681 . _:b376136067 . _:b376136092 . _:b376135521 . _:b376136093 . _:b376136094 . _:b376136680 . _:b376136095 . _:b376136088 . _:b376135520 . _:b376136089 . _:b376136090 . _:b376136683 . _:b376136643 . _:b376136091 . _:b376136084 . _:b376135523 . _:b376136085 . _:b376136086 . _:b376136682 . _:b376135357 . _:b376136087 . _:b376136080 . _:b376135522 . . _:b376135848 . . _:b376136081 . . _:b3471517 . _:b376136693 . _:b376136082 . _:b376136083 . _:b376136108 . _:b376135533 . _:b376136109 . _:b376136110 . _:b376136692 . _:b376136111 . _:b376136104 . _:b376135532 . _:b376136105 . _:b3471523 "Lastly, the addition of DTT, a reducing agent used to activate thiol proteases [>>48<<], did not significantly change protease activity in the effluents." . _:b376136106 . _:b376136695 . _:b376136107 . _:b3471532 "The majority of studies on biofilm detachment have focused on factors capable of initiating the process, such as nutrient availability [54],[>>55<<], nitric oxide exposure [56], oxygen tension [57], iron salts [58], chelators [59], and signaling molecules [60]\u2013[63]." . . _:b376136100 . _:b376135535 . _:b376136101 . _:b376136102 . _:b376136694 . . . _:b376136103 . _:b376136115 . . _:b376135521 . _:b376135534 . _:b376136096 . _:b376135711 . _:b376136097 . _:b376136098 . _:b376136689 . _:b376136099 . _:b376136161 . _:b376136124 . _:b376135529 . _:b376136125 . . _:b376136126 . _:b376136688 . _:b376136127 . "PMC0" . _:b376135528 . _:b376136120 . _:b376136121 . . _:b376136122 . _:b376136691 . _:b376136123 . _:b376136116 . _:b376136518 . _:b376135531 . _:b376136117 . _:b376136118 . _:b376136690 . _:b376136119 . _:b376136068 . . _:b376136112 . _:b376135530 . _:b376136113 . _:b376136114 . _:b376136701 . _:b376136115 . _:b376136140 . _:b376135541 . . _:b376136141 . . _:b376136142 . _:b376136700 . _:b376136143 . _:b376136136 . _:b376135540 . _:b376136137 . _:b376136138 . _:b376136703 . _:b376136139 . _:b376136132 . _:b376135543 . _:b376136133 . _:b376136134 . _:b376136702 . _:b376136135 . _:b376136128 . _:b376135542 . _:b376136129 . . _:b376136130 . _:b376136697 . . _:b376136131 . _:b376136156 . _:b376135537 . _:b376136157 . _:b376136158 . _:b376136696 . . _:b376135438 . _:b376135988 . . _:b376136159 . _:b376136152 . _:b376135536 . . _:b376136153 . _:b376136154 . _:b376136699 . _:b376136155 . _:b376136148 . _:b376136648 . _:b376135539 . . _:b376136149 . . _:b376136698 . _:b376136153 . _:b376136150 . _:b376136151 . _:b376136144 . _:b376135538 . _:b376136145 . . _:b376136146 . _:b376136197 . _:b376136147 . _:b376136172 . _:b376135549 . _:b376136173 . _:b376136174 . _:b376136196 . _:b376136175 . . _:b376136168 . _:b376135548 . _:b376136169 . _:b376135926 . _:b376136199 . _:b376136170 . _:b376135803 . _:b376136165 . . _:b376136171 . _:b376136164 . _:b376135551 . _:b376135223 . _:b376136165 . _:b376136166 . _:b376136198 . _:b376136167 . _:b376136160 . _:b376136395 . _:b376135550 . _:b376136161 . _:b376136162 . _:b376136193 . _:b376136163 . _:b376136188 . _:b376135545 . _:b376136189 . _:b376136190 . _:b376136192 . _:b376136191 . _:b376136184 . _:b376135544 . _:b376136185 . _:b376136186 . _:b376136195 . _:b376136187 . _:b376136180 . _:b376135547 . _:b376136181 . _:b376136182 . _:b376136194 . _:b376136183 . _:b376136074 . . _:b376135546 . _:b376136176 . _:b376136177 . . _:b376136178 . _:b376136205 . _:b376136179 . _:b376135557 . . _:b376136204 . _:b376135556 . _:b3471532 . _:b376136207 . _:b3471503 "The AIP-detached cells were more resistant than broth culture to comparable levels of rifampicin, suggesting parts of the detached biofilm may remain in emboli that are known to possess elevated antibiotic resistance [>>9<<]. These observations demonstrated that S. aureus cells detached from a biofilm regain susceptibility to a clinical antibiotic." . _:b376135559 . _:b376136206 . _:b376135558 . _:b376136201 . . _:b376135553 . _:b376136200 . _:b376135552 . _:b376136203 . _:b376136622 . _:b376135555 . _:b376136202 . . _:b376135554 . . _:b376136213 . _:b376136513 . . _:b376136742 . _:b376135565 . . _:b376136212 . _:b376136813 . . _:b376135564 . _:b376136215 . _:b376135567 . _:b376136214 . . _:b376135566 . _:b376136209 . _:b376135883 . _:b376135561 . _:b376136208 . _:b376135560 . _:b376136211 . . _:b376135563 . _:b376136520 . _:b376136210 . _:b376135562 . _:b376136221 . . _:b376135573 . _:b376135375 . _:b376136220 . . _:b376136159 . _:b376135572 . _:b376136223 . . _:b376135575 . _:b376136222 . _:b376135936 . _:b376135574 . _:b376135295 . _:b376136217 . . _:b376136249 . _:b376136230 . _:b376135569 . . _:b376136608 . _:b376136216 . . _:b376136226 . _:b376135568 . _:b376136219 . . _:b376135242 . . _:b376135571 . _:b376135488 . _:b376136218 . . _:b376135570 . _:b376136229 . _:b376135581 . _:b376135574 . _:b376136228 . . _:b376135580 . _:b376136231 . _:b376135985 . _:b376135798 . . _:b376135583 . _:b376135595 . _:b376136230 . _:b376135582 . . . _:b376135852 . _:b376136225 . _:b376135577 . _:b3471587 . _:b376136224 . _:b376135576 . . _:b376136227 . _:b376135579 . . _:b376136226 . . _:b376135578 . _:b376136237 . . . _:b376135589 . _:b376135437 . _:b376136236 . . _:b376135588 . . _:b376136239 . _:b376135591 . _:b376136612 . _:b376136238 . _:b376135590 . . _:b376136233 . _:b376135585 . _:b376136232 . _:b376135584 . _:b376135267 . _:b376136235 . _:b376135587 . _:b376136234 . _:b376136316 . _:b376135586 . . _:b376136245 . _:b376135597 . . _:b376136244 . _:b376135596 . . _:b376136247 . _:b376135599 . . _:b376136246 . . _:b376135598 . . _:b376136241 . _:b376135593 . . _:b376136240 . . _:b376135592 . _:b376136243 . _:b376135595 . _:b376135773 . _:b376136242 . _:b376135322 . _:b376135594 . . _:b376136195 . _:b376136253 . _:b376135605 . _:b376136252 . _:b376135604 . . _:b376136255 . . _:b376135607 . . _:b376136254 . _:b376135606 . _:b376135561 . _:b3471569 . _:b376136249 . _:b376135601 . _:b376136248 . _:b376136835 . _:b376135600 . . _:b376136251 . _:b376135603 . _:b376136250 . _:b376135602 . _:b376136261 . _:b376136698 . _:b376135613 . . _:b376136260 . . _:b376135633 . _:b376135612 . _:b3471557 . . _:b376136440 . _:b376136263 . _:b376135615 . _:b376135440 . _:b376136262 . _:b376135614 . _:b3471553 "The RNAIII repression is not due to glucose itself, but results from the mild acid conditions [26] and can be mimicked with other carbon sources, such as galactose [>>20<<], that also lower the media pH." . _:b376135533 . _:b376136257 . . _:b376135609 . _:b376136256 . _:b376135608 . _:b376136259 . _:b376135611 . _:b376136258 . . _:b376135610 . . . _:b376136269 . _:b376135705 . _:b376135621 . _:b376136057 . . _:b376136268 . _:b376135620 . _:b3471501 . _:b376136271 . . _:b376135623 . . _:b376136270 . _:b376135622 . _:b376136644 . _:b376136705 . _:b376136265 . . _:b376135617 . _:b376136190 . _:b376136264 . _:b376136319 . _:b376135616 . . _:b376135552 . _:b376136267 . _:b376135619 . _:b3471587 "Quorum-sensing has been implicated in dispersal of biofilms formed by Yersinia pseudotuberculosis [79], Rhodobacter sphaeroides [80], Pseudomonas aureofaciens [81], Xanthomonas capmestris [>>62<<], and Serratia marceascens [61]." . _:b376136266 . _:b376135618 . _:b376136350 . _:b376135722 . _:b376136277 . _:b376136377 . _:b376135629 . _:b3471473 "To determine relative protease activities of strains, assays were performed as described previously using the Azocoll (Calbiochem) reagent [>>48<<]. For measuring protease levels in biofilm effluents, 100 mL of effluent was collected on ice (\u223C12 hours) after AIP addition to the biofilm medium. Cells were removed from the effluents through centrifugation and filtering, and ammonium" . _:b376135608 . _:b376136276 . _:b376136349 . _:b376135628 . _:b376135238 . _:b376136781 . _:b376136279 . . _:b376135796 . _:b376135631 . _:b376136278 . _:b376136085 . _:b376135630 . _:b376136273 . _:b376136283 . _:b376135625 . _:b376136272 . _:b376135233 . _:b376135624 . . _:b376136275 . _:b376135627 . _:b376136274 . _:b376135626 . _:b376136285 . . _:b376135637 . _:b376135695 . _:b376136284 . _:b376135636 . _:b376135544 . _:b376136287 . . _:b376135639 . _:b3471516 . . _:b376136743 . _:b376136286 . _:b376135638 . _:b3471519 . . _:b376135793 . _:b376136281 . . _:b376135633 . _:b376136280 . . _:b376135632 . _:b376136283 . _:b376135278 . _:b376135635 . . _:b376136282 . _:b376135634 . _:b376135571 . _:b376136293 . _:b376135645 . _:b376136292 . . . _:b376135644 . _:b376136295 . _:b376135647 . _:b376135812 . _:b376136294 . _:b376135646 . . _:b376136289 . . . _:b376135641 . _:b376136288 . _:b376135605 . _:b376135640 . _:b376135726 . _:b376136291 . _:b376135643 . . . _:b376135950 . _:b376136290 . _:b376135642 . _:b376136301 . _:b376135653 . . _:b376136300 . _:b376135652 . _:b376136290 . . _:b376136303 . _:b376135655 . _:b376136030 . _:b376136302 . _:b376136802 . _:b376135654 . _:b376136297 . _:b376136524 . _:b376136321 . _:b376135649 . _:b376135413 . _:b376136241 . _:b376136296 . _:b376135648 . . . _:b376136299 . _:b376136484 . _:b376135651 . _:b376136825 . . _:b376136424 . _:b376136298 . _:b376136719 . _:b376135650 . . . . _:b376136309 . _:b376135661 . . _:b376136308 . _:b3471546 "Alternatively, detachment studies have addressed effector gene products that contribute to the dissolution of the biofilm, including surfactants [10],[13],[64],[65], hydrolases [66],[67], proteases [37]\u2013[>>39<<], and DNase [68]." . _:b376136658 . _:b376135660 . . _:b376135202 . _:b376136311 . _:b376135663 . . _:b376135739 . . _:b376136310 . _:b376135662 . _:b3471545 "Alternatively, detachment studies have addressed effector gene products that contribute to the dissolution of the biofilm, including surfactants [10],[13],[64],[65], hydrolases [66],[67], proteases [>>37<<]\u2013[39], and DNase [68]." . . _:b376135516 . _:b376136193 . _:b376136305 . _:b376135657 . . _:b376135414 . . _:b376136304 . _:b376136055 . _:b376135656 . . _:b376136307 . . _:b376135659 . _:b376135507 . _:b376136306 . _:b376135658 . _:b376136750 . _:b376136242 . . _:b376136317 . _:b376135669 . _:b376136058 . . _:b376136316 . _:b376135668 . _:b376136319 . _:b376135671 . _:b376136543 . _:b376136318 . . . _:b376135670 . . _:b376136313 . _:b376135665 . . _:b376135683 . _:b376136312 . _:b376135664 . _:b376136826 . _:b376135800 . _:b376136315 . _:b376135667 . . _:b376136314 . _:b376135666 . _:b376136325 . _:b376135677 . . _:b376136324 . . _:b376135676 . _:b376135528 . . _:b376136327 . _:b376135679 . _:b376136326 . _:b376136735 . _:b376135678 . _:b376136321 . _:b376135405 . _:b376135673 . _:b376136320 . _:b376135672 . _:b376136649 . _:b376136323 . . _:b376135675 . . _:b376136322 . _:b376135887 . _:b376135674 . . _:b376136697 . _:b376136333 . . _:b376136716 . _:b376136717 . _:b376136718 . _:b376136332 . _:b376136719 . _:b376136712 . _:b376136713 . _:b376136714 . _:b376136335 . _:b376136715 . _:b376136708 . _:b376135226 . _:b376136709 . _:b376136710 . _:b376136334 . . . _:b376136711 . _:b376136024 . _:b376136704 . . _:b376136705 . . _:b376136706 . _:b376136329 . _:b376136134 . _:b376135642 . _:b376136707 . _:b376136732 . _:b376136488 . _:b376135335 . _:b376136733 . _:b376136734 . _:b376136328 . _:b376136735 . _:b376136728 . . _:b376136729 . _:b376136730 . _:b376136331 . _:b376136731 . _:b376136168 . _:b376136724 . _:b376136725 . _:b376136726 . _:b376136330 . . _:b376136727 . _:b376136720 . _:b376135541 . _:b376136721 . _:b376136722 . _:b376136779 . _:b376136341 . _:b376136723 . . _:b376135715 . _:b376136748 . _:b376136749 . _:b3471565 . _:b376136750 . _:b376136340 . _:b376136751 . _:b376136744 . _:b376136745 . _:b376136746 . _:b376136343 . _:b376135219 . _:b376136747 . . _:b376136740 . _:b376136741 . _:b376136742 . _:b376136342 . _:b376136743 . _:b376136736 . . _:b376136737 . _:b376136738 . _:b376136337 . _:b376136739 . _:b376136764 . _:b376135738 . _:b376136765 . _:b376136766 . _:b376136336 . _:b376136288 . _:b376136767 . . _:b376136760 . _:b376136761 . _:b376136762 . _:b376136339 . _:b376136763 . _:b376136756 . _:b3471534 . _:b376136757 . _:b376136758 . _:b376136338 . _:b376135860 . _:b376136759 . _:b376136752 . _:b376136753 . _:b376136754 . _:b376136349 . _:b376136755 . _:b376135189 . _:b376136780 . _:b376136781 . _:b376136782 . _:b376136348 . _:b376136783 . _:b376135188 . _:b376136776 . _:b376136777 . _:b376136778 . _:b376136382 . _:b376136351 . _:b376136779 . _:b376135373 . _:b376135191 . _:b376136772 . _:b376136773 . _:b376136774 . _:b376136350 . . _:b376136775 . _:b376135981 . _:b376135190 . _:b376135302 . _:b376136768 . _:b376136769 . _:b376136770 . _:b376136345 . . _:b376136771 . _:b376135451 . _:b376136796 . _:b376136797 . _:b376136798 . _:b376136344 . _:b376136799 . _:b376136792 . _:b376136793 . _:b376136794 . _:b376136347 . _:b376136795 . _:b376135573 . _:b3471568 . . _:b376136788 . _:b376136789 . . _:b376136790 . _:b376136346 . _:b376136791 . _:b376135224 . _:b376136784 . _:b376136785 . _:b376136786 . _:b376136357 . _:b376136787 . _:b376135197 . _:b376136812 . _:b376136813 . _:b376136814 . _:b376136356 . . _:b376136111 . _:b376136815 . _:b376135196 . _:b376136808 . _:b376136809 . _:b376135690 . _:b376136810 . _:b376136359 . _:b376136811 . _:b376135199 . _:b376136804 . _:b376136805 . _:b376136806 . _:b376136358 . . _:b376135895 . _:b376136807 . . _:b376135198 . _:b376136800 . _:b376136801 . _:b376136802 . _:b376136794 . _:b376136353 . _:b376136803 . _:b376135193 . _:b376136828 . _:b376135689 . _:b376136829 . . _:b376136352 . _:b376136830 . _:b376136831 . . _:b376135192 . _:b376136824 . _:b376136825 . _:b376136826 . _:b376136355 . . _:b376136827 . _:b376135195 . _:b376136820 . _:b376136821 . _:b376136822 . _:b376136354 . _:b376136823 . _:b376135194 . _:b376136816 . . _:b376136817 . _:b376136818 . _:b376136365 . _:b376136819 . _:b376135205 . _:b376136844 . _:b376136845 . _:b376136846 . _:b376136364 . _:b376136847 . _:b376135204 . _:b376135500 . _:b376136840 . . _:b376136594 . _:b376136841 . _:b376136842 . _:b376136367 . _:b376136843 . . . _:b376135207 . _:b376136836 . _:b376136837 . _:b376136838 . _:b376136366 . _:b376136839 . . _:b376136832 . _:b376135206 . _:b376136833 . _:b376136834 . _:b376136361 . _:b376136835 . . _:b376135201 . . . _:b3471496 . _:b376136360 . _:b376135200 . . _:b376136363 . _:b376135203 . _:b376136852 . _:b376136853 . _:b376136854 . _:b376136362 . _:b376135202 . _:b376136848 . _:b376136849 . _:b376136850 . _:b376136373 . _:b376136851 . _:b376135213 . _:b376135298 . _:b376136372 . . _:b376135212 . . _:b376136375 . _:b376135215 . . . _:b376136374 . . _:b3471441 . _:b376135214 . . _:b376136369 . _:b376136829 . _:b376135209 . . _:b376136368 . _:b376135208 . _:b376136095 . . . _:b376136371 . _:b376135654 . _:b376135211 . . _:b376136370 . _:b376136704 . . _:b376135210 . . _:b376136381 . _:b376135221 . . _:b376136380 . . _:b376135220 . _:b376136665 . . _:b376136383 . _:b376135223 . _:b376136382 . _:b376135222 . _:b376136816 . . _:b376136707 . _:b376136377 . _:b376135217 . _:b376136263 . _:b376136376 . _:b376135216 . _:b376136379 . _:b376135219 . . _:b376136378 . . _:b376135218 . _:b376136529 . _:b376135736 . _:b376136389 . _:b376135229 . _:b376136388 . . _:b376135228 . _:b3471558 "Biofilms are dynamic and dispersal is always operating [11], but accelerated detachment has been observed in response to changing environmental conditions, such as oxygen levels [57],[69], nutrient depletion [>>54<<], changing nutrient composition [55], or increased concentration of quorum-sensing signals [61]." . . _:b376135275 . _:b376136391 . _:b376135231 . _:b376136390 . _:b376135230 . _:b376136385 . . _:b376135494 . _:b376135225 . _:b3471506 . _:b376136384 . _:b376136843 . . _:b376135224 . _:b376136387 . _:b376135227 . _:b376136386 . . _:b376135466 . _:b376135226 . _:b376136397 . _:b376136397 . _:b3471566 "material is important for SH1000 biofilm integrity, and this result supports a number of recent studies demonstrating that proteases can inhibit biofilm formation or detach established biofilms from many S. aureus strains [35], [>>37<<]\u2013[39]. It is not clear whether agr-mediated detachment will function in S. aureus strains that produce an ica-dependent biofilm." . _:b376135237 . _:b376136396 . _:b376135236 . . _:b376136399 . _:b376135239 . _:b376136749 . _:b376135657 . _:b376136398 . _:b376135238 . . . _:b376136393 . _:b376135233 . _:b376136699 . _:b376136392 . _:b376135232 . _:b376135423 . _:b376136578 . _:b376136395 . _:b376135235 . . . . _:b376136394 . . _:b376135234 . _:b376136405 . _:b376135245 . . _:b376136769 . _:b376136404 . . _:b376135244 . _:b376136271 . _:b376135321 . _:b376136407 . _:b376135247 . _:b376135599 . _:b376136406 . _:b376135246 . _:b376135249 . . _:b376136401 . _:b376135241 . . . _:b3471505 . _:b376136400 . _:b376135240 . . . _:b376136403 . _:b3471559 "are dynamic and dispersal is always operating [11], but accelerated detachment has been observed in response to changing environmental conditions, such as oxygen levels [57],[69], nutrient depletion [54], changing nutrient composition [>>55<<], or increased concentration of quorum-sensing signals [61]." . _:b376135243 . _:b376135365 . . _:b376136402 . _:b376135242 . _:b3471489 "The flow cell media was supplemented with glucose to attenuate agr expression [>>20<<], allowing cell attachment and biofilm development." . _:b376136413 . _:b376135253 . _:b376136823 . _:b376136122 . _:b376136412 . _:b376135252 . _:b376136450 . _:b376135422 . _:b3471508 . _:b376136415 . . _:b376135255 . _:b376135261 . _:b376136414 . _:b376135615 . _:b376135254 . _:b376136544 . _:b376136409 . _:b376135249 . _:b376136408 . _:b3471564 "In contrast, dispersin B does detach S. epidermidis biofilms indicating a more significant role for PIA in the S. epidermidis matrix structure [>>70<<]. Our experiments with proteinase K and the S. aureus proteases indicate that some proteinaceous material is important for SH1000 biofilm integrity, and this result supports a number of recent studies demonstrating that proteases can" . _:b376135248 . _:b376136347 . _:b3471483 . _:b376135410 . _:b376136449 . _:b376136411 . . . _:b3471446 "Surprisingly, the opposite is true in S. aureus, as the presence of an active quorum-sensing impedes attachment and development of a biofilm [13],[>>14<<]. The S. aureus quorum-sensing system is encoded by the accessory gene regulator (agr) locus and the communication molecule that it produces and senses is called an autoinducing peptide (AIP), which is an eight-residue peptide with the" . _:b376135251 . _:b376136410 . _:b376135250 . _:b376135928 . _:b376136421 . _:b376135261 . _:b376136420 . _:b376135260 . _:b376136423 . _:b376135263 . _:b376136422 . _:b376135262 . . . _:b376136417 . _:b376135257 . . . _:b376136416 . _:b376135256 . _:b376136209 . _:b376136419 . _:b376135259 . _:b376135984 . _:b376136418 . . . _:b376135258 . _:b376136429 . _:b376136652 . . _:b376135207 . _:b376135269 . . _:b376136025 . _:b3471530 _:b3471564 . _:b376136428 . _:b3471530 _:b3471565 . _:b376136791 . _:b3471530 _:b3471566 . . _:b376135268 . _:b3471530 _:b3471567 . _:b376136817 . _:b3471530 _:b3471560 . _:b376136431 . _:b3471530 _:b3471561 . _:b3471530 _:b3471562 . _:b376136545 . _:b376135271 . _:b3471530 _:b3471563 . _:b3471530 _:b3471556 . _:b376136430 . _:b3471530 _:b3471557 . _:b3471530 _:b3471558 . _:b376135706 . _:b376135270 . _:b3471530 _:b3471559 . _:b3471530 _:b3471552 . _:b376136425 . _:b376135581 . _:b3471530 _:b3471553 . . _:b3471530 _:b3471554 . _:b376135265 . _:b3471530 _:b3471555 . _:b3471530 _:b3471580 . _:b376136424 . _:b3471530 _:b3471581 . _:b3471530 _:b3471582 . _:b376135264 . _:b3471530 _:b3471583 . . _:b376136467 . _:b376136427 . _:b3471530 _:b3471576 . _:b3471530 _:b3471577 . _:b3471530 _:b3471578 . _:b376136773 . _:b376135823 . _:b376135267 . _:b3471530 _:b3471579 . _:b3471530 _:b3471572 . _:b376136426 . _:b3471530 _:b3471573 . _:b3471530 _:b3471574 . _:b376136257 . _:b376135266 . _:b3471530 _:b3471575 . _:b3471530 _:b3471568 . _:b376136437 . _:b3471530 _:b3471569 . _:b376136076 . _:b3471530 _:b3471570 . _:b376135277 . _:b3471530 _:b3471571 . _:b376136436 . _:b376135276 . _:b376136439 . . . _:b376135279 . _:b3471530 _:b3471588 . _:b376136828 . _:b376136734 . _:b376136438 . _:b3471530 _:b3471589 . _:b3471530 _:b3471590 . _:b376135390 . _:b376135278 . _:b3471530 _:b3471591 . _:b3471530 _:b3471584 . _:b3471582 "There is growing evidence that extracellular DNA (eDNA) is an important S. aureus biofilm matrix component [24],[>>70<<], and expression of staphylococcal nuclease is reported to be under control of the agr system [18]." . _:b376136433 . _:b3471530 _:b3471585 . _:b3471530 _:b3471586 . _:b376135273 . _:b3471530 _:b3471587 . _:b376136432 . _:b376135272