金黄色葡萄球菌Al-2群体感应系统的调控
详细信息    本馆镜像全文|  推荐本文 |  |   获取CNKI官网全文
摘要
近年来的研究发现,细胞之间的信息交流不单单存在于多细胞生物中,细菌的细胞之间也存在着相互交流来协调行为方式。细菌在增殖的过程中,会产生一些次级代谢产物,有些次级代谢产物可以作为化学信号在细菌细胞间传递信息。这种信号分子的浓度会随着细菌的增殖而在胞外积累,即信号分子的浓度反映了细菌细胞的密度。当信号分子积累到一定的阈值浓度时,可被细菌感知,与相应的受体结合后在群体范围内引发一系列的基因调控,使细菌能在多细胞水平上采取协调一致的行动来完成一些重要的生理学功能,如生物发光、生物膜的形成、细胞分化、运动性、致病菌的毒力因子的诱导、抗生素与细菌素的合成等。这些重要的生理功能单凭细菌个体是无法完成的。这种信号分子称为自诱导物,这一过程称为群体感应或密度依赖的基因调控,这一调控系统称为群体感应系统。大多数细菌都有群体感应系统,在革兰氏阴性细菌中的种内信号通讯使用的语言是酰基高丝氨酸内酯(AHLs),革兰氏阳性细菌利用寡肽作为信号分子实现种内细胞通讯。不同种的细菌之间也能进行交流,交流所用的语言是Autoinducer-2 (AI-2),这种信号分子存在于大多数细菌中,是目前所知的唯一能进行种内和种间交流的通用语言。AI-2由LuxS催化合成,luxS基因广泛存在于革兰氏阴性细菌和革兰氏阳性细菌中,且具有很高的保守性。LuxS是细菌硫代谢中甲基循环中一个代谢酶,在代谢过程中AI-2作为副产物被合成。所以LuxS肩负着代谢和信号传递的双重功能,因此成为近年来研究的一个热点。但是针对于某一种细菌来说,AI-2信号系统通常不是起到主导地位的群体感应系统,和主要的群体感应一起共同参与基因的调控,所以研究起来相对比较困难。目前有很多研究证明LuxS/AI-2在多种细菌中能发挥信号调控功能,参与调控这些细菌一些重要的生物学途径,如在哈氏弧菌Vibrio harveyi中参与调控生物发光现象,在大肠杆菌Escherichia coli中参与调控生物膜的形成,在霍乱弧菌Vibrio cholerae中参与调控致病性,在链球菌Streptococcus anginosus中参与调控其对抗生素的敏感性等。然而在可以广泛引起人畜疾病的革兰氏阳性菌金黄色葡萄球菌中,LuxS/AI-2系统是否具有信号调控的功能,如果有信号调控功能,AI-2群体感应系统参与哪些生理功能的调控,调控的方式如何等等问题还没有详细的研究报道。
     金黄色葡萄球菌在环境中无处不在,能引起医院或社区获得感染,是一种非常重要的条件致病菌。金黄色葡萄球菌的感染能引起人畜多种疾病,从皮肤的浅表感染如丘疹、脓包、疥疮、烫伤样皮肤综合症,到可以致死的深层感染如肺炎、脑膜炎、骨髓炎、心内膜炎、中毒性休克综合症以及败血症等。金黄色葡萄球菌之所以有很强的致病性,主要归结于其能产生大量的毒性因子。这些毒性因子包括在金黄色葡萄球菌在生长的延滞期和对数前期表达的细胞表面毒力因子,如表面蛋白、超抗原、一些抗吞噬因子等,这些毒素因子能促进细菌在宿主表面的粘附。在对数后期和稳定期生长阶段,金黄色葡萄球菌表达的毒性因子主要是一些分泌到胞外的酶和外毒素等,能够促进对宿主的入侵和感染。这些毒性因子的产生与生长周期相关,大多都受金黄色葡萄球菌中已知的群体感应系统Agr系统的调控,同时也受一些重要的调控子的调控。金黄色葡萄球菌中也存在LuxS,而且具有合成AI-2的活性,因此我们感兴趣的是它是否能作为信号分子参与基因的调控。
     本课题通过基因芯片和实时荧光定量PCR等技术分析比较了金黄色葡萄球菌标准菌株NCTC8325的野生型、luxS基因敲除菌株以及在敲除菌株中添加外源AI-2时,这些菌株基因表达转录谱的差异。结果显示在luxS基因敲除菌株中荚膜多糖(Capsular Polysaccharide, CP)基因cap和二元信号系统kdpDE的转录水平都发生了变化,并且改变的水平能被AI-2回补。CP是金黄色葡萄球菌所产生的毒性因子之一,属于细胞表面成分,在侵染过程中能够起到抗吞噬的作用使细菌免受宿主免疫细胞杀伤。有趣的是被报道的能调控cap操纵子的调控子如yabJ-spoVG, arlRS, agr, sbcDC, ccpA, mgr, sae,以及sarA等的转录水平在luxS敲除菌株中都没有变化。因此我们推测,金黄色葡萄球菌中AI-2群体感应系统应该是通过一个未知的途径调控CP的转录。KdpDE由感应蛋白KdpD和效应蛋白KdpE组成一个二元信号系统,最先在大肠杆菌中被阐述与环境中K+缺少或高渗透压有关。在致病菌结核分枝杆菌Mycobacterium tuberculosis中kdpDE基因敲出后能导致其毒性增强,金黄色葡萄球菌中也存在KdpDE系统,虽然有报道它受环境压力的调控但是目前还没有具体功能的研究报道。为了研究KdpDE和CP之间关系,我们获得了kdpDE敲除菌株,发现kdpDE敲除后,CP的转录水平下降,DNA凝胶阻滞实验证明了KdpE可以结合到cap基因的启动子上直接调控其表达。kdpE基因敲除和互补以及KdpE磷酸化位点突变实验证明了KdpDE系统是通过磷酸化传递途径实现其对荚膜多糖表达的调控。细胞吞噬实验显示AI-2作为信号分子能调控生物膜的形成和细菌的抗吞噬能力,此结果和荚膜多糖的转录水平一致进一步验证了证明了我们的推测,即AI-2群体感应系统通过二元信号系统KdpDE调控荚膜多糖的表达进而影响一些表型的变化。此研究为LuxS/AI-2系统在金黄色葡萄球菌中的信号调控功能提供了直接的证据,首次阐述了二元信号系统KdpDE在金葡菌中与致病性相关的具体功能,为金葡菌感染的治疗提供了新的启示。
Recently people found cell-cell communication is not just in multi-cellular organism, bacteria can also communicate with one another to coordinate their behavior. In the process of proliferation, bacteria secrete small diffusible molecules called autoinducers (AIs) continuously. While bacteria proliferated, AIs accumulated in the around environment, once reached a threshold concentration AIs can be detected and enter the cell, bind to its receptors and regulate transcription of lots of target genes. Thus bacteria can coordinate social behavior at multi-cellular level, such as bioluminescence, biofilm formation, swarming behavior, antibiotic production, and virulence factor secretion. This process is referred to as quorum sensing (QS), or density-dependent gene regulation, and this system is called QS system. Many QS mechanisms have evolved among bacteria. In general, gram-negative bacteria use acylated homoserine lactones (AHLs) as AIs, and gram-positive bacteria use oligopeptide AIs, which act through two-component phosphorelay cascades. There is one mechanism that is shared by both gram-positive and gram-negative bacteria, involving the production of autoinducer 2 (AI-2). In contrast to other autoinducers that are species specific, AI-2 is widely present in bacteria, leading to the suggestion that it is a universal language for interspecies communication. AI-2 is byproduct synthesized by LuxS enzyme in a metabolic pathway known as the activated methyl cycle. LuxS is conserved and widely present in both gram-negative and gram-positive bacteria. Due to its dual roles in metabolism and in QS, has been a hot topic to study, however, it is difficulty to find out its real rule in QS since it is not the main QS system and it is regulated by other regulators. The LuxS/AI-2 system is known to be functional as a QS system involved in the regulation of a range of behaviours in diverse bacteria, such as bioluminescence in Vibrio harveyi, biofilm formation in Escherichia coli, virulence-associated traits in Vibrio cholerae, and antibiotic susceptibility in Streptococcus anginosu. However, AI-2 QS role in gram-positive bacteria, especially in S. aureus, has not been studied in detail until now.
     S. aureus is a major nosocomial pathogen with the ability to cause a variety of infectious diseases, from relatively benign skin infections such as pimples, impetigo, furuncles, and scalded skin syndrome, to potentially fatal systemic disorders such as pneumonia, meningitis, osteomyelitis and septicemia. The strong pathogenesis of S. aureus is essentially determined by its virulence factors, including surface-associated adhesins, superantigens, exoenzymes and exotoxin, which are regulated by a wide range of regulatory systems. Among these regulatory elements, the Agr system (the accessory gene regulator) is the only characterized QS system in S. aureus. Interestingly, S. aureus also possesses a functional luxS gene and has the capability to produce AI-2. It will be of great importance to explore whether AI-2 can function as a QS signal to regulate physiological functions in S. aureus.
     In this study, we analyzed the transcript differences between the standard strains of S. aureus NCTC8325 wild type, the luxS mutant and the luxS mutant added exogenous AI-2 using microarray and real time RT-PCR. Our data show that Inactivation of luxS in S. aureus NCTC8325 resulted in higher transcription of capsular polysaccharide (CP) synthesis genes and the two component system kdpDE genes. The survival rate of the luxS mutant was higher than that of the wild type both in human blood and macrophage U937. Addition of exogenous AI-2 restored all the parental phenotypes by a concentration-dependent mechanism. CP is an important cell wall component that can interact with the host immune system during the invasive process, allowing the organism to resist uptake and killing by phagocytes. It is interesting that the transcript levels of various regulatory elements known to modulate CP synthesis in S. aureus such as agrA, sarA, sbcDC, rnaⅢarlRS, ccpA, mgrA, saeRS, and spoVG displayed no apparent changes in luxS mutant. So we suspected that LuxS/AI-2 modulated cap gene transcription through another mechanism. Sensor protein KdpD together with reaction protein KdpE constitutes a two-component signal transduction system, which was first characterized in E. coli. In this organism, KdpDE regulate severe K+ limitation or osmotic upshift. In Mycobacterium tuberculosis, deletion of kdpDE resulted in increased virulence. Although several reports have shown that, in S. aureus, the transcript level of kdpDE changes under certain environmental stresses, information about the role of KdpDE in S. aureus and how it functions remains incomplete.
     To study the relationship between KdpDE and CP, we constructed kdpDE mutant strain. Our data show that the transcript levels of cap genes were decreased in kdpDE mutant and gel-shift assay show that KdpE can bind to the promoter region of the cap operon, suggesting that the KdpDE system could regulate cap gene transcription. kdpE mutant and KdpE phosphorylation site mutant assays indicated that KdpE regulates the transcription of cap through a phosphorylation pathway. The alterated survival of S. aureus in human blood and monocytic cells correlated with the changes in transcript levels of CP. The data further validated our hypothesis that S. aureus AI-2 quorum sensing regulates CP synthesis and virulence through the two-component regulatory system KdpDE. Our study provided a direct proof that the LuxS/AI-2 system played a signaling role in S. aureus and new clues to the functional analysis of the KdpDE system in S. aureus. Our findings add new understanding to AI-2 quorum sensing regulation and mechanisms of innate immune evasion used by S. aureus and provide novel clues for antimicrobial chemotherapy of Staphylococal infection.
引文
Ahmed, N.A., Petersen, F.C., and Scheie, A.A. (2007) AI-2 quorum sensing affects antibiotic susceptibility in Streptococcus anginosus[J]. J Antimicrob Chemother 60:49-53.
    Ahmed, N.A., Petersen, F.C., and Scheie, A.A. (2009) AI-2/LuxS is involved in increased biofilm formation by Streptococcus intermedius in the presence of antibiotics[J]. Antimicrob Agents Chemother 53:4258-4263.
    Ahmed, S., Meghji, S., Williams, R.J., Henderson, B., Brock, J.H., and Nair, S.P. (2001) Staphylococcus aureus fibronectin binding proteins are essential for internalization by osteoblasts but do not account for differences in intracellular levels of bacteria[J]. Infect Immun 69:2872-2877.
    Allison, C., and Hughes, C. (1991) Bacterial swarming:an example of prokaryotic differentiation and multicellular behaviour[J]. Sci Prog 75:403-422.
    Altendorf, K., Voelkner, P., and Puppe, W. (1994) The sensor kinase KdpD and the response regulator KdpE control expression of the kdpFABC operon in Escherichia coli[J]. Res Microbiol 145:374-381.
    Anand, S.K., and Griffiths, M.W. (2003) Quorum sensing and expression of virulence in Escherichia coli O157:H7[J]. Int J Food Microbiol 85:1-9.
    Antunes, L.C., and Ferreira, R.B. (2009) Intercellular communication in bacteria[J]. Crit Rev Microbiol 35:69-80.
    Arbeit, R.D., Karakawa, W.W., Vann, W.F., and Robbins, J.B. (1984) Predominance of two newly described capsular polysaccharide types among clinical isolates of Staphylococcus aureus[J]. Diagn Microbiol Infect Dis 2:85-91.
    Arbeit, R.D., and Dunn, R.M. (1987) Expression of capsular polysaccharide during experimental focal infection with Staphylococcus aureus[J]. J Infect Dis 156:947-952.
    Auger, S., Krin, E., Aymerich, S., and Gohar, M. (2006) Autoinducer 2 affects biofilm formation by Bacillus cereus[J]. Appl Environ Microbiol 72:937-941.
    Ballal, A., Basu, B., and Apte, S.K. (2007) The Kdp-ATPase system and its regulation[J]. J Biosci 32:559-568.
    Barnard, A.M., and Salmond, G.P. (2007) Quorum sensing in Erwinia species[J]. Anal Bioanal Chem 387:415-423.
    Bassler, B.L., Wright, M., Showalter, R.E., and Silverman, M.R. (1993) Intercellular signalling in Vibrio harveyi:sequence and function of genes regulating expression of luminescence[J]. Mol Microbiol 9:773-786.
    Bassler, B.L. (1999) How bacteria talk to each other:regulation of gene expression by quorum sensing[J]. Curr Opin Microbiol 2:582-587.
    Bassler, B.L. (2002) Small talk. Cell-to-cell communication in bacteria[J]. Cell 109:421-424.
    Bassler, B.L. (2004) Cell-to-cell communication in bacteria:a chemical discourse. Harvey Lect 100:123-142.
    Bayles, K.W., Wesson, C.A., Liou, L.E., Fox, L.K., Bohach, G.A., and Trumble, W.R. (1998) Intracellular Staphylococcus aureus escapes the endosome and induces apoptosis in epithelial cells[J]. Infect Immun 66:336-342.
    Beenken, K.E., Blevins, J.S., and Smeltzer, M.S. (2003) Mutation of sarA in Staphylococcus aureus limits biofilm formation[J]. Infect Immun 71:4206-4211.
    Beeston, A.L., and Surette, M.G. (2002) pfs-dependent regulation of autoinducer 2 production in Salmonella enterica serovar Typhimurium[J]. J Bacteriol 184:3450-3456.
    Benito, Y., Kolb, F.A., Romby, P., Lina, G., Etienne, J., and Vandenesch, F. (2000) Probing the structure of RNAIII, the Staphylococcus aureus agr regulatory RNA, and identification of the RNA domain involved in repression of protein A expression[J]. Rna 6:668-679.
    Blevins, J.S., Gillaspy, A.F., Rechtin, T.M., Hurlburt, B.K., and Smeltzer, M.S. (1999) The Staphylococcal accessory regulator (sar) represses transcription of the Staphylococcus aureus collagen adhesin gene (cna) in an agr-independent manner[J]. Mol Microbiol 33:317-326.
    Blosser-Middleton, R.S., and Gray, K.M. (2001) Multiple N-acyl homoserine lactone signals of Rhizobium leguminosarum are synthesized in a distinct temporal pattern[J]. J Bacteriol 183: 6771-6777.
    Camilli, A., and Bassler, B.L. (2006) Bacterial small-molecule signaling pathways[J]. Science 311:1113-1116.
    Chen, X., Schauder, S., Potier, N., Van Dorsselaer, A., Pelczer, I., Bassler, B.L., and Hughson, F.M. (2002) Structural identification of a bacterial quorum-sensing signal containing boron[J]. Nature 415:545-549.
    Chen, Z., Luong, T.T., and Lee, C.Y. (2007) The sbcDC locus mediates repression of type 5 capsule production as part of the SOS response in Staphylococcus aureus[J]. J Bacteriol 189: 7343-7350.
    Cheung, A.L., Koomey, J.M., Butler, C.A., Projan, S.J., and Fischetti, V.A. (1992) Regulation of exoprotein expression in Staphylococcus aureus by a locus (sar) distinct from agr[J]. Proc Natl Acad Sci U S A 89:6462-6466.
    Cheung, A.L., Eberhardt, K.J., Chung, E., Yeaman, M.R., Sullam, P.M., Ramos, M., and Bayer, A.S. (1994) Diminished virulence of a sar-/agr-mutant of Staphylococcus aureus in the rabbit model of endocarditis[J]. J Clin Invest 94:1815-1822.
    Cheung, A.L., and Projan, S.J. (1994) Cloning and sequencing of sarA of Staphylococcus aureus, a gene required for the expression of agr[J]. J Bacteriol 176:4168-4172.
    Cheung, A.L., and Ying, P. (1994) Regulation of alpha-and beta-hemolysins by the sar locus of Staphylococcus aureus[J]. J Bacteriol 176:580-585.
    Cheung, A.L., Eberhardt, K., and Heinrichs, J.H. (1997) Regulation of protein A synthesis by the sar and agr loci of Staphylococcus aureus[J]. Infect Immun 65:2243-2249.
    Cheung, A.L., Chien, Y.T., and Bayer, A.S. (1999) Hyperproduction of alpha-hemolysin in a sigB mutant is associated with elevated SarA expression in Staphylococcus aureus[J]. Infect Immun 67:1331-1337.
    Cheung, A.L., Schmidt, K., Bateman, B., and Manna, A.C. (2001) SarS, a SarA homolog repressible by agr, is an activator of protein A synthesis in Staphylococcus aureus[J]. Infect Immun 69:2448-2455.
    Cheung, A.L., and Zhang, G. (2002) Global regulation of virulence determinants in Staphylococcus aureus by the SarA protein family[J]. Front Biosci 7:d1825-1842.
    Chien, Y., and Cheung, A.L. (1998) Molecular interactions between two global regulators, sar and agr, in Staphylococcus aureus[J]. J Biol Chem 273:2645-2652.
    Chien, Y., Manna, A.C., Projan, S.J., and Cheung, A.L. (1999) SarA, a global regulator of virulence determinants in Staphylococcus aureus, binds to a conserved motif essential for sar-dependent gene regulation[J]. J Bioi Chem 274:37169-37176.
    Choi, S.H., and Greenberg, E.P. (1991) The C-terminal region of the Vibrio fischeri LuxR protein contains an inducer-independent lux gene activating domain[J]. Proc Natl Acad Sci U S A 88: 11115-11119.
    Cunnion, K.M., Lee, J.C., and Frank, M.M. (2001) Capsule production and growth phase influence binding of complement to Staphylococcus aureus[J]. Infect Immun 69:6796-6803.
    De Keersmaecker, S.C., Varszegi, C., van Boxel, N., Habel, L.W., Metzger, K., Daniels, R., Marchal, K., De Vos, D., and Vanderleyden, J. (2005) Chemical synthesis of (S)-4,5-dihydroxy-2,3-pentanedione, a bacterial signal molecule precursor, and validation of its activity in Salmonella typhimurium[J]. J Biol Chem 280:19563-19568.
    De Keersmaecker, S.C., Sonck, K., and Vanderleyden, J. (2006) Let LuxS speak up in AI-2 signaling[J]. Trends Microbiol 14:114-119.
    de Kievit, T.R. (2009) Quorum sensing in Pseudomonas aeruginosa biofilms[J]. Environ Microbiol 11:279-288.
    DeLisa, M.P., Valdes, J.J., and Bentley, W.E. (2001a) Mapping stress-induced changes in autoinducer AI-2 production in chemostat-cultivated Escherichia coli K-12[J]. J Bacteriol 183: 2918-2928.
    DeLisa, M.P., Valdes, J.J., and Bentley, W.E. (2001b) Quorum signaling via AI-2 communicates the "Metabolic Burden" associated with heterologous protein production in Escherichia coli[J]. Biotechnol Bioeng 75:439-450.
    Dickschat, J.S. Quorum sensing and bacterial biofilms[J]. Nat Prod Rep 27:343-369.
    Dinges, M.M., Orwin, P.M., and Schlievert, P.M. (2000) Exotoxins of Staphylococcus aureus. Clin Microbiol Rev 13:16-34.
    Dubern, J.F., and Diggle, S.P. (2008) Quorum sensing by 2-alkyl-4-quinolones in Pseudomonas aeruginosa and other bacterial species[J]. Mol Biosyst 4:882-888.
    Dunman, P.M., Murphy, E., Haney, S., Palacios, D., Tucker-Kellogg, G., Wu, S., Brown, E.L. Zagursky, R.J., Shlaes, D., and Projan, S.J. (2001) Transcription profiling-based identification of Staphylococcus aureus genes regulated by the agr and/or sarA loci[J]. J Bacteriol 183: 7341-7353.
    Dunny, G.M., and Leonard, B.A. (1997) Cell-cell communication in gram-positive bacteria[J]. Annu Rev Microbiol 51:527-564.
    Dziewanowska, K., Patti, J.M., Deobald, C.F., Bayles, K.W., Trumble, W.R., and Bohach, G.A. (1999) Fibronectin binding protein and host cell tyrosine kinase are required for internalization of Staphylococcus aureus by epithelial cells[J]. Infect Immun 67:4673-4678.
    Eberhard, A. (1972) Inhibition and activation of bacterial luciferase synthesis[J]. J Bacteriol 109: 1101-1105.
    Eberhard, A., Burlingame, A.L., Eberhard, C., Kenyon, G.L., Nealson, K.H., and Oppenheimer, N.J. (1981) Structural identification of autoinducer of Photobacterium fischeri luciferase[J]. Biochemistry 20:2444-2449.
    Egland, K.A., and Greenberg, E.P. (2001) Quorum sensing in Vibrio fischeri:analysis of the LuxR DNA binding region by alanine-scanning mutagenesis[J]. J Bacteriol 183:382-386.
    Elvers, K.T., and Park, S.F. (2002) Quorum sensing in Campylobacter jejuni:detection of a luxS encoded signalling molecule[J]. Microbiology 148:1475-1481.
    Fattom, A.I., Sarwar, J., Ortiz, A., and Naso, R. (1996) A Staphylococcus aureus capsular polysaccharide (CP) vaccine and CP-specific antibodies protect mice against bacterial challenge[J]. Infect Immun 64:1659-1665.
    Federle, M.J. (2009) Autoinducer-2-based chemical communication in bacteria:complexities of interspecies signaling[J]. Contrib Microbiol 16:18-32.
    Foster, T.J., and McDevitt, D. (1994) Surface-associated proteins of Staphylococcus aureus:their possible roles in virulence[J]. FEMS Microbiol Lett 118:199-205.
    Foster, T.J. (2005) Immune evasion by staphylococci[J]. Nat Rev Microbiol 3:948-958.
    Fournier, B., Klier, A., and Rapoport, G. (2001) The two-component system ArlS-ArlR is a regulator of virulence gene expression in Staphylococcus aureus[J]. Mol Microbiol 41: 247-261.
    Fournier, B., and Klier, A. (2004) Protein A gene expression is regulated by DNA supercoiling which is modified by the ArlS-ArlR two-component system of Staphylococcus aureus[J]. Microbiology 150:3807-3819.
    Fuqua, W.C., Winans, S.C., and Greenberg, E.P. (1994) Quorum sensing in bacteria:the LuxR-LuxI family of cell density-responsive transcriptional regulators[J]. J Bacteriol 176: 269-275.
    Goerke, C., Fluckiger, U., Steinhuber, A., Bisanzio, V., Ulrich, M., Bischoff, M., Patti, J.M., and Wolz, C. (2005) Role of Staphylococcus aureus global regulators sae and sigmaB in virulence gene expression during device-related infection[J]. Infect Immun 73:3415-3421.
    Hanzelka, B.L., and Greenberg, E.P. (1995) Evidence that the N-terminal region of the Vibrio fischeri LuxR protein constitutes an autoinducer-binding domain[J]. J Bacteriol 177:815-817.
    Hardman, A.M., Stewart, G.S., and Williams, P. (1998) Quorum sensing and the cell-cell communication dependent regulation of gene expression in pathogenic and non-pathogenic bacteria[J]. Antonie Van Leeuwenhoek 74:199-210.
    Heermann, R., Fohrmann, A., Altendorf, K., and Jung, K. (2003) The transmembrane domains of the sensor kinase KdpD of Escherichia coli are not essential for sensing K+ limitation[J]. Mol Microbiol 47:839-848.
    Holden, I., Swift, I., and Williams, I. (2000) New signal molecules on the quorum-sensing block. Trends Microbiol 8:101-104; discussion 103-104.
    Holden, M.T., Ram Chhabra, S., de Nys, R., Stead, P., Bainton, N.J., Hill, P.J., Manefield, M., Kumar, N., Labatte, M., England, D., Rice, S., Givskov, M., Salmond, G.P., Stewart, G.S., Bycroft, B.W., Kjelleberg, S., and Williams, P. (1999) Quorum-sensing cross talk:isolation and chemical characterization of cyclic dipeptides from Pseudomonas aeruginosa and other gram-negative bacteria[J]. Mol Microbiol 33:1254-1266.
    Huntzinger, E., Boisset, S., Saveanu, C., Benito, Y., Geissmann, T., Namane, A., Lina, G., Etienne, J., Ehresmann, B., Ehresmann, C., Jacquier, A., Vandenesch, F., and Romby, P. (2005) Staphylococcus aureus RNAIII and the endoribonuclease III coordinately regulate spa gene expression[J]. Embo J 24:824-835.
    Il'ina, T.S., Romanova Iu, M., and Gintsburg, A.L. (2006) [Communication systems in bacteria and their role in pathogenicity]. Mol Gen Mikrobiol Virusol:22-29.
    Janssens, J.C., De Keersmaecker, S.C., De Vos, D.E., and Vanderleyden, J. (2008) Small molecules for interference with cell-cell-communication systems in Gram-negative bacteria[J]. Curr Med Chem 15:2144-2156.
    Janzon, L., Lofdahl, S., and Arvidson, S. (1989) Identification and nucleotide sequence of the delta-lysin gene, hid, adjacent to the accessory gene regulator (agr) of Staphylococcus aureus[J]. Mol Gen Genet 219:480-485.
    Janzon, L., and Arvidson, S. (1990) The role of the delta-lysin gene (hid) in the regulation of virulence genes by the accessory gene regulator (agr) in Staphylococcus aureus[J]. Embo J 9: 1391-1399.
    Ji, G., Pei, W., Zhang, L., Qiu, R., Lin, J., Benito, Y., Lina, G., and Novick, R.P. (2005) Staphylococcus intermedius produces a functional agr autoinducing peptide containing a cyclic lactone[J]. J Bacteriol 187:3139-3150.
    Kaiser, D., and Losick, R. (1993) How and why bacteria talk to each other[J]. Cell 73:873-885.
    Kampen, A.H., Tollersrud, T., and Lund, A. (2005) Staphylococcus aureus capsular polysaccharide types 5 and 8 reduce killing by bovine neutrophils in vitro[J]. Infect Immun 73: 1578-1583.
    Kaplan, H.B., and Greenberg, E.P. (1985) Diffusion of autoinducer is involved in regulation of the Vibrio fischeri luminescence system[J]. J Bacteriol 163:1210-1214.
    Karakawa, W.W., Sutton, A., Schneerson, R., Karpas, A., and Vann, W.F. (1988) Capsular antibodies induce type-specific phagocytosis of capsulated Staphylococcus aureus by human polymorphonuclear leukocytes[J]. Infect Immun 56:1090-1095.
    Keller, L., and Surette, M.G. (2006) Communication in bacteria:an ecological and evolutionary perspective[J]. Nat Rev Microbiol 4:249-258.
    Kleerebezem, M., Quadri, L.E., Kuipers, O.P., and de Vos, W.M. (1997) Quorum sensing by peptide pheromones and two-component signal-transduction systems in Gram-positive bacteria[J]. Mol Microbiol 24:895-904.
    Knobloch, J.K., Jager, S., Horstkotte, M.A., Rohde, H., and Mack, D. (2004) RsbU-dependent regulation of Staphylococcus epidermidis biofilm formation is mediated via the alternative sigma factor sigmaB by repression of the negative regulator gene icaR[J]. Infect Immun 72: 3838-3848.
    Koenig, R.L., Ray, J.L., Maleki, S.J., Smeltzer, M.S., and Hurlburt, B.K. (2004) Staphylococcus aureus AgrA binding to the RNAIII-agr regulatory region[J]. J Bacteriol 186:7549-7555.
    Kong, K.F., Vuong, C., and Otto, M. (2006) Staphylococcus quorum sensing in biofilm formation and infection[J]. Int J Med Microbiol 296:133-139.
    Krin, E., Chakroun, N., Turlin, E., Givaudan, A., Gaboriau, F., Bonne, I., Rousselle, J.C., Frangeul, L., Lacroix, C., Hullo, M.F., Marisa, L., Danchin, A., and Derzelle, S. (2006) Pleiotropic role of quorum-sensing autoinducer 2 in Photorhabdus luminescens[J]. Appl Environ Microbiol 72:6439-6451.
    Lee, C.Y., and J. C. Lee. (2000) Staphylococcal capsule. Washington, D.C:ASM Press.
    Lee, J.C., Perez, N.E., Hopkins, C.A., and Pier, G.B. (1988) Purified capsular polysaccharide-induced immunity to Staphylococcus aureus infection[J]. J Infect Dis 157: 723-730.
    Lee, J.C., Takeda, S., Livolsi, P.J., and Paoletti, L.C. (1993) Effects of in vitro and in vivo growth conditions on expression of type 8 capsular polysaccharide by Staphylococcus aureus[J]. Infect Immun 61:1853-1858.
    Lee, J.C., Xu, S., Albus, A., and Livolsi, P.J. (1994) Genetic analysis of type 5 capsular polysaccharide expression by Staphylococcus aureus[J]. J Bacteriol 176:4883-4889.
    Lee, J.C., Park, J.S., Shepherd, S.E., Carey, V., and Fattom, A. (1997) Protective efficacy of antibodies to the Staphylococcus aureus type 5 capsular polysaccharide in a modified model of endocarditis in rats[J]. Infect Immun 65:4146-4151.
    Lenz, D.H., Mok, K.C., Lilley, B.N., Kulkarni, R.V., Wingreen, N.S., and Bassler, B.L. (2004) The small RNA chaperone Hfq and multiple small RNAs control quorum sensing in Vibrio harveyi and Vibrio cholerae[J]. Cell 118:69-82.
    Li, J., Attila, C., Wang, L., Wood, T.K., Valdes, J.J., and Bentley, W.E. (2007) Quorum sensing in Escherichia coli is signaled by AI-2/LsrR:effects on small RNA and biofilm architecture[J]. J Bacteriol 189:6011-6020.
    Lilley, B.N., and Bassler, B.L. (2000) Regulation of quorum sensing in Vibrio harveyi by LuxO and sigma-54[J]. Mol Microbiol 36:940-954.
    Liu, Y., Manna, A.C., Pan, C.H., Kriksunov, I.A., Thiel, D.J., Cheung, A.L., and Zhang, G. (2006) Structural and function analyses of the global regulatory protein SarA from Staphylococcus aureus[J]. Proc Natl Acad Sci U S A 103:2392-2397.
    Lowy, F.D. (1998) Staphylococcus aureus infections[J]. N Engl J Med 339:520-532.
    Luong, T., Sau, S., Gomez, M., Lee, J.C., and Lee, C.Y. (2002) Regulation of Staphylococcus aureus capsular polysaccharide expression by agr and sarA[J]. Infect Immun 70:444-450.
    Luong, T.T., and Lee, C.Y. (2002) Overproduction of type 8 capsular polysaccharide augments Staphylococcus aureus virulence[J]. Infect Immun 70:3389-3395.
    Luong, T.T., Newell, S.W., and Lee, C.Y. (2003) Mgr, a novel global regulator in Staphylococcus aureus[J]. J Bacteriol 185:3703-3710.
    Luong, T.T., Dunman, P.M., Murphy, E., Projan, S.J., and Lee, C.Y. (2006) Transcription Profiling of the mgrA Regulon in Staphylococcus aureus[J]. J Bacteriol 188:1899-1910.
    Luong, T.T., and Lee, C.Y. (2006) The arl locus positively regulates Staphylococcus aureus type 5 capsule via an mgrA-dependent pathway[J]. Microbiology 152:3123-3131.
    Lyon, G.J., Mayville, P., Muir, T.W., and Novick, R.P. (2000) Rational design of a global inhibitor of the virulence response in Staphylococcus aureus, based in part on localization of the site of inhibition to the receptor-histidine kinase, AgrC[J]. Proc Natl Acad Sci U S A 97: 13330-13335.
    Lyon, G.J., and Novick, R.P. (2004) Peptide signaling in Staphylococcus aureus and other Gram-positive bacteria[J]. Peptides 25:1389-1403.
    Manna, A.C., Bayer, M.G., and Cheung, A.L. (1998) Transcriptional analysis of different promoters in the sar locus in Staphylococcus aureus[J]. J Bacteriol 180:3828-3836.
    Manna, A.C., and Cheung, A.L. (2003) sarU, a sarA homolog, is repressed by SarT and regulates virulence genes in Staphylococcus aureus[J]. Infect Immun 71:343-353.
    Manna, A.C., Ingavale, S.S., Maloney, M., van Wamel, W., and Cheung, A.L. (2004) Identification of sarV (SA2062), a new transcriptional regulator, is repressed by SarA and MgrA (SA0641) and involved in the regulation of autolysis in Staphylococcus aureus[J]. J Bacteriol 186:5267-5280.
    Manna, A.C., and Cheung, A.L. (2006a) Transcriptional regulation of the agr locus and the identification of DNA binding residues of the global regulatory protein SarR in Staphylococcus aureus[J]. Mol Microbiol 60:1289-1301.
    Manna, A.C., and Cheung, A.L. (2006b) Expression of SarX, a negative regulator of agr and exoprotein synthesis, is activated by MgrA in Staphylococcus aureus[J]. J Bacteriol 188: 4288-4299.
    Manna, A.C., and Ray, B. (2007) Regulation and characterization of rot transcription in Staphylococcus aureus[J]. Microbiology 153:1538-1545.
    McCallum, N., Bischoff, M., Maki, H., Wada, A., and Berger-Bachi, B. (2004) TcaR, a putative MarR-like regulator of sarS expression[J]. J Bacteriol 186:2966-2972.
    McKenney, D., Hubner, J., Muller, E., Wang, Y, Goldmann, D.A., and Pier, G.B. (1998) The ica locus of Staphylococcus epidermidis encodes production of the capsular polysaccharide/adhesin[J]. Infect Immun 66:4711-4720.
    McNab, R., Ford, S.K., El-Sabaeny, A., Barbieri, B., Cook, G.S., and Lamont, R.J. (2003) LuxS-based signaling in Streptococcus gordonii:autoinducer 2 controls carbohydrate metabolism and biofilm formation with Porphyromonas gingivalis[J]. J Bacteriol 185: 274-284.
    Meier, S., Goerke, C., Wolz, C., Seidl, K., Homerova, D., Schulthess, B., Kormanec, J., Berger-Bachi, B., and Bischoff, M. (2007) sigmaB and the sigmaB-dependent arlRS and yabJ-spoVG loci affect capsule formation in Staphylococcus aureus[J]. Infect Immun 75: 4562-4571.
    Menzies, B.E., and Kourteva, I. (1998) Internalization of Staphylococcus aureus by endothelial cells induces apoptosis[J]. Infect Immun 66:5994-5998.
    Merritt, J., Kreth, J., Shi, W., and Qi, F. (2005) LuxS controls bacteriocin production in Streptococcus mutans through a novel regulatory component[J]. Mol Microbiol 57:960-969.
    Miller, M.B., and Bassler, B.L. (2001) Quorum sensing in bacteria[J]. Annu Rev Microbiol 55: 165-199.
    Miller, M.B., Skorupski, K., Lenz, D.H., Taylor, R.K., and Bassler, B.L. (2002) Parallel quorum sensing systems converge to regulate virulence in Vibrio cholerae[J]. Cell 110:303-314.
    Miller, S.T., Xavier, K.B., Campagna, S.R., Taga, M.E., Semmelhack, M.F., Bassler, B.L., and Hughson, F.M. (2004) Salmonella typhimurium recognizes a chemically distinct form of the bacterial quorum-sensing signal AI-2[J]. Mol Cell 15:677-687.
    Moreau, M., Richards, J.C., Fournier, J.M., Byrd, R.A., Karakawa, W.W., and Vann, W.F. (1990) Structure of the type 5 capsular polysaccharide of Staphylococcus aureus[J]. Carbohydr Res 201:285-297.
    Moslehi-Jenabian, S., Gori, K., and Jespersen, L. (2009) AI-2 signalling is induced by acidic shock in probiotic strains of Lactobacillus spp[J]. Int J Food Microbiol 135:295-302.
    Muir, T.W. (2003) Turning virulence on and off in staphylococci[J]. J Pept Sci 9:612-619.
    Murthy, S.V., Melly, M.A., Harris, T.M., Hellerqvist, C.G., and Hash, J.H. (1983) The repeating sequence of the capsular polysaccharide of Staphylococcus aureus M. Carbohydr Res 117: 113-123.
    Nealson, K.H., Platt, T., and Hastings, J.W. (1970) Cellular control of the synthesis and activity of the bacterial luminescent system[J]. J Bacteriol 104:313-322.
    Nealson, K.H., and Hastings, J.W. (1979) Bacterial bioluminescence:its control and ecological significance[J]. Microbiol Rev 43:496-518.
    Ng, W.L., and Bassler, B.L. (2009) Bacterial quorum-sensing network architectures[J]. Annu Rev Genet 43:197-222.
    Nicholas, R.O., Li, T., McDevitt, D., Marra, A., Sucoloski, S., Demarsh, P.L., and Gentry, D.R. (1999) Isolation and characterization of a sigB deletion mutant of Staphylococcus aureus[J]. Infect Immun 67:3667-3669.
    Nilsson, I.M., Lee, J.C., Bremell, T., Ryden, C., and Tarkowski, A. (1997) The role of staphylococcal polysaccharide microcapsule expression in septicemia and septic arthritis[J]. Infect Immun 65:4216-4221.
    Novick, R.P., Ross, H.F., Projan, S.J., Kornblum, J., Kreiswirth, B., and Moghazeh, S. (1993) Synthesis of staphylococcal virulence factors is controlled by a regulatory RNA molecule[J]. Embo J 12:3967-3975.
    Novick, R.P., and Geisinger, E. (2008) Quorum sensing in staphylococci[J]. Annu Rev Genet 42: 541-564.
    Nyvad, B., and Kilian, M. (1987) Microbiology of the early colonization of human enamel and root surfaces in vivo[J]. Scand J Dent Res 95:369-380.
    O'Riordan, K., and Lee, J.C. (2004) Staphylococcus aureus capsular polysaccharides[J]. Clin Microbiol Rev 17:218-234.
    Oscarsson, J., Harlos, C., and Arvidson, S. (2005) Regulatory role of proteins binding to the spa (protein A) and sarS (staphylococcal accessory regulator) promoter regions in Staphylococcus aureus NTCC 8325-4. Int J Med Microbiol 295:253-266.
    Otto, M. (2001) Staphylococcus aureus and Staphylococcus epidermidis peptide pheromones produced by the accessory gene regulator agr system[J]. Peptides 22:1603-1608.
    Pane-Farre, J., Jonas, B., Forstner, K., Engelmann, S., and Hecker, M. (2006) The sigmaB regulon in Staphylococcus aureus and its regulation[J]. Int J Med Microbiol 296:237-258.
    Parish, T., Smith, D.A., Kendall, S., Casali, N., Bancroft, G.J., and Stoker, N.G. (2003) Deletion of two-component regulatory systems increases the virulence of Mycobacterium tuberculosis. Infect Immun 71:1134-1140.
    Parsek, M.R., and Greenberg, E.P. (2000) Acyl-homoserine lactone quorum sensing in gram-negative bacteria:a signaling mechanism involved in associations with higher organisms. Proc Natl Acad Sci U S A 97:8789-8793.
    Poutrel, B., Boutonnier, A., Sutra, L., and Fournier, J.M. (1988) Prevalence of capsular polysaccharide types 5 and 8 among Staphylococcus aureus isolates from cow, goat, and ewe milk[J]. J Clin Microbiol 26:38-40.
    Poutrel, B., Gilbert, F.B., and Lebrun, M. (1995) Effects of culture conditions on production of type 5 capsular polysaccharide by human and bovine Staphylococcus aureus strains[J]. Clin Diagn Lab Immunol 2:166-171.
    Pragman, A.A., and Schlievert, P.M. (2004) Virulence regulation in Staphylococcus aureus:the need for in vivo analysis of virulence factor regulation[J]. FEMS Immunol Med Microbiol 42: 147-154.
    Pragman, A.A., Yarwood, J.M., Tripp, T.J., and Schlievert, P.M. (2004) Characterization of virulence factor regulation by SrrAB, a two-component system in Staphylococcus aureus[J]. J Bacteriol 186:2430-2438.
    Pragman, A.A., Herron-Olson, L., Case, L.C., Vetter, S.M., Henke, E.E., Kapur, V., and Schlievert, P.M. (2007a) Sequence analysis of the Staphylococcus aureus srrAB loci reveals that truncation of srrA affects growth and virulence factor expression[J]. J Bacteriol 189: 7515-7519.
    Pragman, A.A., Ji, Y., and Schlievert, P.M. (2007b) Repression of Staphylococcus aureus SrrAB using inducible antisense srrA alters growth and virulence factor transcript levels[J]. Biochemistry 46:314-321.
    Projan, S.J.a.N., R.P. (1997) The molecular basis of pathogenicity. In the staphylococci in human disease. New York, N.Y., Churchill Livingstone:55-81.
    Qiu, R., Pei, W., Zhang, L., Lin, J., and Ji, G. (2005) Identification of the putative staphylococcal AgrB catalytic residues involving the proteolytic cleavage of AgrD to generate autoinducing peptide[J]. J Biol Chem 280:16695-16704.
    Rachid, S., Ohlsen, K., Wallner, U., Hacker, J., Hecker, M., and Ziebuhr, W. (2000) Alternative transcription factor sigma(B) is involved in regulation of biofilm expression in a Staphylococcus aureus mucosal isolate[J]. J Bacteriol 182:6824-6826.
    Rickard, A.H., Palmer, R.J., Jr., Blehert, D.S., Campagna, S.R., Semmelhack, M.F., Egland, P.G., Bassler, B.L., and Kolenbrander, P.E. (2006) Autoinducer 2:a concentration-dependent signal for mutualistic bacterial biofilm growth[J]. Mol Microbiol 60:1446-1456.
    Risley, A.L., Loughman, A., Cywes-Bentley, C., Foster, T.J., and Lee, J.C. (2007) Capsular polysaccharide masks clumping factor A-mediated adherence of Staphylococcus aureus to fibrinogen and platelets[J]. J Infect Dis 196:919-927.
    Rodelas, B., Lithgow, J.K., Wisniewski-Dye, F., Hardman, A., Wilkinson, A., Economou, A., Williams, P., and Downie, J.A. (1999) Analysis of quorum-sensing-dependent control of rhizosphere-expressed (rhi) genes in Rhizobium leguminosarum bv. viciae[J]. J Bacteriol 181: 3816-3823.
    Rooijakkers, S.H., van Kessel, K.P., and van Strijp, J.A. (2005) Staphylococcal innate immune evasion[J]. Trends Microbiol 13:596-601.
    Said-Salim, B., Dunman, P.M., McAleese, F.M., Macapagal, D., Murphy, E., McNamara, P.J., Arvidson, S., Foster, T.J., Projan, S.J., and Kreiswirth, B.N. (2003) Global regulation of Staphylococcus aureus genes by Rot[J]. J Bacteriol 185:610-619.
    Sanchez-Contreras, M., Bauer, W.D., Gao, M., Robinson, J.B., and Allan Downie, J. (2007) Quorum-sensing regulation in rhizobia and its role in symbiotic interactions with legumes[J]. Philos Trans R Soc Lond B Biol Sci 362:1149-1163.
    Sau, S., and Lee, C.Y. (1996) Cloning of type 8 capsule genes and analysis of gene clusters for the production of different capsular polysaccharides in Staphylococcus aureus[J]. J Bacteriol 178:2118-2126.
    Schauder, S., Shokat, K., Surette, M.G., and Bassler, B.L. (2001) The LuxS family of bacterial autoinducers:biosynthesis of a novel quorum-sensing signal molecule[J]. Mol Microbiol 41: 463-476.
    Schmidt, K.A., Manna, A.C., Gill, S., and Cheung, A.L. (2001) SarT, a repressor of alpha-hemolysin in Staphylococcus aureus[J]. Infect Immun 69:4749-4758.
    Schmidt, K.A., Manna, A.C., and Cheung, A.L. (2003) SarT influences sarS expression in Staphylococcus aureus[J]. Infect Immun 71:5139-5148.
    Seidl, K., Stucki, M., Ruegg, M., Goerke, C., Wolz, C., Harris, L., Berger-Bachi, B., and Bischoff, M. (2006) Staphylococcus aureus CcpA affects virulence determinant production and antibiotic resistance[J]. Antimicrob Agents Chemother 50:1183-1194.
    Semmelhack, M.F., Campagna, S.R., Hwa, C., Federle, M.J., and Bassler, B.L. (2004) Boron binding with the quorum sensing signal AI-2 and analogues[J]. Org Lett 6:2635-2637.
    Senadheera, D., and Cvitkovitch, D.G. (2008) Quorum sensing and biofilm formation by Streptococcus mutans[J]. Adv Exp Med Biol 631:178-188.
    Senn, M.M., Giachino, P., Homerova, D., Steinhuber, A., Strassner, J.; Kormanec, J., Fluckiger, U., Berger-Bachi, B., and Bischoff, M. (2005) Molecular analysis and organization of the sigmaB operon in Staphylococcus aureus[J]. J Bacteriol 187:8006-8019.
    Smith, R.S., and Iglewski, B.H. (2003) P. aeruginosa quorum-sensing systems and virulence[J]. Curr Opin Microbiol 6:56-60.
    Soell, M., Diab, M., Haan-Archipoff, G., Beretz, A., Herbelin, C., Poutrel, B., and Klein, J.P. (1995) Capsular polysaccharide types 5 and 8 of Staphylococcus aureus bind specifically to human epithelial (KB) cells, endothelial cells, and monocytes and induce release of cytokines[J]. Infect Immun 63:1380-1386.
    Steinhuber, A., Goerke, C., Bayer, M.G., Doring, G., and Wolz, C. (2003) Molecular architecture of the regulatory Locus sae of Staphylococcus aureus and its impact on expression of virulence factors[J]. J Bacteriol 185:6278-6286.
    Sterba, K.M., Mackintosh, S.G., Blevins, J.S., Hurlburt, B.K., and Smeltzer, M.S. (2003) Characterization of Staphylococcus aureus SarA binding sites[J]. J Bacteriol 185:4410-4417.
    Sturme, M.H., Kleerebezem, M., Nakayama, J., Akkermans, A.D., Vaugha, E.E., and de Vos, W.M. (2002) Cell to cell communication by autoinducing peptides in gram-positive bacteria[J]. Antonie Van Leeuwenhoek 81:233-243.
    Sturme, M.H., Francke, C., Siezen, R.J., de Vos, W.M., and Kleerebezem, M. (2007) Making sense of quorum sensing in lactobacilli:a special focus on Lactobacillus plantarum WCFS1[J]. Microbiology 153:3939-3947.
    Taga, M.E., Semmelhack, J.L., and Bassler, B.L. (2001) The LuxS-dependent autoinducer AI-2 controls the expression of an ABC transporter that functions in AI-2 uptake in Salmonella typhimurium[J]. Mol Microbiol 42:777-793.
    Taga, M.E., Miller, S.T, and Bassler, B.L. (2003) Lsr-mediated transport and processing of AI-2 in Salmonella typhimurium[J]. Mol Microbiol 50:1411-1427.
    Tavender, T.J., Halliday, N.M., Hardie, K.R., and Winzer, K. (2008) LuxS-independent formation of AI-2 from ribulose-5-phosphate[J]. BMC Microbiol 8:98.
    Tegmark, K., Karlsson, A., and Arvidson, S. (2000) Identification and characterization of SarH1, a new global regulator of virulence gene expression in Staphylococcus aureus[J]. Mol Microbiol 37:398-409.
    Thakker, M., Park, J.S., Carey, V., and Lee, J.C. (1998) Staphylococcus aureus serotype 5 capsular polysaccharide is antiphagocytic and enhances bacterial virulence in a murine bacteremia model[J]. Infect Immun 66:5183-5189.
    Thimme, R., Blum, H.E., and Weber, F. (1998) [Quorum sensing:a mechanism of communication between bacteria]. Dtsch Med Wochenschr 123:1183-1184.
    Trotonda, M.P., Manna, A.C., Cheung, A.L., Lasa, I., and Penades, J.R. (2005) SarA positively controls bap-dependent biofilm formation in Staphylococcus aureus[J]. J Bacteriol 187: 5790-5798.
    Ulrich, M., Bastian, M., Cramton, S.E., Ziegler, K., Pragman, A.A., Bragonzi, A., Memmi, G, Wolz, C., Schlievert, P.M., Cheung, A., and Doring, G. (2007) The staphylococcal respiratory response regulator SrrAB induces ica gene transcription and polysaccharide intercellular adhesin expression, protecting Staphylococcus aureus from neutrophil killing under anaerobic growth conditions[J]. Mol Microbiol 65:1276-1287.
    Valle, J., Toledo-Arana, A., Berasain, C., Ghigo, J.M., Amorena, B., Penades, J.R., and Lasa, I. (2003) SarA and not sigmaB is essential for biofilm development by Staphylococcus aureus[J]. Mol Microbiol 48:1075-1087.
    Van Houdt, R., Givskov, M., and Michiels, C.W. (2007) Quorum sensing in Serratia[J]. FEMS Microbiol Rev 31:407-424.
    van Wamel, W., Xiong, Y.Q., Bayer, A.S., Yeaman, M.R., Nast, C.C., and Cheung, A.L. (2002) Regulation of Staphylococcus aureus type 5 capsular polysaccharides by agr and sarA in vitro and in an experimental endocarditis model[J]. Microb Pathog 33:73-79.
    Vandenesch, F., Kornblum, J., and Novick, R.P. (1991) A temporal signal, independent of agr, is required for hla but not spa transcription in Staphylococcus aureus[J]. J Bacteriol 173: 6313-6320.
    Vendeville, A., Winzer, K., Heurlier, K., Tang, C.M., and Hardie, K.R. (2005) Making'sense'of metabolism:autoinducer-2, LuxS and pathogenic bacteria. Nat Rev Microbiol 3:383-396.
    Venturi, V. (2006) Regulation of quorum sensing in Pseudomonas[J]. FEMS Microbiol Rev 30: 274-291.
    Visick, K.L., Foster, J., Doino, J., McFall-Ngai, M., and Ruby, E.G. (2000) Vibrio fischeri lux genes play an important role in colonization and development of the host light organ[J]. J Bacteriol 182:4578-4586.
    Voelkner, P., Puppe, W., and Altendorf, K. (1993) Characterization of the KdpD protein, the sensor kinase of the K(+)-translocating Kdp system of Escherichia coli[J]. Eur J Biochem 217: 1019-1026.
    von Bodman, S.B., Majerczak, D.R., and Coplin, D.L. (1998) A negative regulator mediates quorum-sensing control of exopolysaccharide production in Pantoea stewartii subsp. stewartii[J]. Proc Natl Acad Sci U S A 95:7687-7692.
    von Bodman, S.B., Willey, J.M., and Diggle, S.P. (2008) Cell-cell communication in bacteria: united we stand[J]. J Bacteriol 190:4377-4391.
    Voyich, J.M., Braughton, K.R., Sturdevant, D.E., Whitney, A.R., Said-Salim, B., Porcella, S.F., Long, R.D., Dorward, D.W., Gardner, D.J., Kreiswirth, B.N., Musser, J.M., and DeLeo, F.R. (2005) Insights into mechanisms used by Staphylococcus aureus to avoid destruction by human neutrophils[J]. J Immunol 175:3907-3919.
    Voyich, J.M., Vuong, C., DeWald, M., Nygaard, T.K., Kocianova, S., Griffith, S., Jones, J., Iverson, C., Sturdevant, D.E., Braughton, K.R., Whitney, A.R., Otto, M., and Deleo, F.R. (2009) The SaeR/S Gene Regulatory System Is Essential for Innate Immune Evasion by Staphylococcus aureus[J]. Journal of Infectious Diseases 199:1698-1706.
    Walderhaug, M.O., Polarek, J.W., Voelkner, P., Daniel, J.M., Hesse, J.E., Altendorf, K., and Epstein, W. (1992) KdpD and KdpE, proteins that control expression of the kdpABC operon, are members of the two-component sensor-effector class of regulators[J]. J Bacteriol 174: 2152-2159.
    Waters, C.M., and Bassler, B.L. (2005) Quorum sensing:cell-to-cell communication in bacteria[J]. Annu Rev Cell Dev Biol 21:319-346.
    Watts, A., Ke, D., Wang, Q., Pillay, A., Nicholson-Weller, A., and Lee, J.C. (2005) Staphylococcus aureus strains that express serotype 5 or serotype 8 capsular polysaccharides differ in virulence[J]. Infect Immun 73:3502-3511.
    Wen, Z.T., and Burne, R.A. (2004) LuxS-mediated signaling in Streptococcus mutans is involved in regulation of acid and oxidative stress tolerance and biofilm formation[J]. J Bacteriol 186: 2682-2691.
    West, A.H., and Stock, A.M. (2001) Histidine kinases and response regulator proteins in two-component signaling systems[J]. Trends Biochem Sci 26:369-376.
    Winzer, K., Hardie, K.R., Burgess, N., Doherty, N., Kirke, D., Holden, M.T., Linforth, R., Cornell, K.A., Taylor, A.J., Hill, P.J., and Williams, P. (2002) LuxS:its role in central metabolism and the in vitro synthesis of 4-hydroxy-5-methyl-3(2H)-furanone[J]. Microbiology 148:909-922.
    Winzer, K., Hardie, K.R., and Williams, P. (2003) LuxS and autoinducer-2:their contribution to quorum sensing and metabolism in bacteria[J]. Adv Appl Microbiol 53:291-396.
    Wisniewski-Dye, F., and Downie, J.A. (2002) Quorum-sensing in Rhizobium[J]. Antonie Van Leeuwenhoek 81:397-407.
    Xavier, K.B., and Bassler, B.L. (2003) LuxS quorum sensing:more than just a numbers game[J]. Curr Opin Microbiol 6:191-197.
    Xavier, K.B., and Bassler, B.L. (2005) Interference with AI-2-mediated bacterial cell-cell communication[J]. Nature 437:750-753.
    Xiong, Y.Q., Bayer, A.S., Yeaman, M.R., Van Wamel, W., Manna, A.C., and Cheung, A.L. (2004) Impacts of sarA and agr in Staphylococcus aureus strain Newman on fibronectin-binding protein A gene expression and fibronectin adherence capacity in vitro and in experimental infective endocarditis[J]. Infect Immun 72:1832-1836.
    Xu, L., Li, H., Vuong, C., Vadyvaloo, V., Wang, J., Yao, Y., Otto, M., and Gao, Q. (2006) Role of the luxS quorum-sensing system in biofilm formation and virulence of Staphylococcus epidermidis[J]. Infect Immun 74:488-496.
    Zhu, J., Miller, M.B., Vance, R.E., Dziejman, M., Bassler, B.L., and Mekalanos, J.J. (2002) Quorum-sensing regulators control virulence gene expression in Vibrio cholerae[J]. Proc Natl Acad Sci U S A 99:3129-3134.
    Ziebandt, A.K., Weber, H., Rudolph, J., Schmid, R., Hoper, D., Engelmann, S., and Hecker, M. (2001) Extracellular proteins of Staphylococcus aureus and the role of SarA and sigma B[J]. Proteomics 1:480-493.
    Ziebandt, A.K., Becher, D., Ohlsen, K., Hacker, J., Hecker, M., and Engelmann, S. (2004) The influence of agr and sigmaB in growth phase dependent regulation of virulence factors in Staphylococcus aureus[J]. Proteomics 4:3034-3047.

© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号

地址:北京市海淀区学院路29号 邮编:100083

电话:办公室:(+86 10)66554848;文献借阅、咨询服务、科技查新:66554700