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  • Review Article
  • Published:

Staphylococcus epidermidis — the 'accidental' pathogen

Nature Reviews Microbiology volume 7, pages 555–567 (2009)Cite this article

Key Points

  • Staphylococcus epidermidis is a common member of the human epithelial microflora and one of the most frequent nosocomial pathogens.

  • S. epidermidis is mostly involved with indwelling medical device-associated infections.The prevalence of S. epidermidis in this type of infection is likely to be due to its abundance on the human skin and its capacity to adhere to catheter surfaces and form biofilms.

  • Biofilm formation, exopolymers and other mechanisms protect S. epidermidis from antibiotics and host defences.

  • Efficient S. epidermidis biofilm formation is dependent on both protein and exopolysaccharide aggregation substances.

  • S. epidermidis can sense the presence of antimicrobial peptides and trigger defensive responses against this type of innate host defence mechanism, which it encounters in its natural habitat.

  • S. epidermidis functions as a reservoir for genes that can be transferred to Staphylococcus aureus, enhancing the pathogenic success and antibiotic resistance of this more dangerous pathogen.

  • S. epidermidis does not produce aggressive toxins and its immune evasion factors probably have original functions in the commensal lifestyle of this species. This indicates that S. epidermidis infection is 'accidental' in nature.

Abstract

Although nosocomial infections by Staphylococcus epidermidis have gained much attention, this skin-colonizing bacterium has apparently evolved not to cause disease, but to maintain the commonly benign relationship with its host. Accordingly, S. epidermidis does not produce aggressive virulence determinants. Rather, factors that normally sustain the commensal lifestyle of S. epidermidis seem to give rise to additional benefits during infection. Furthermore, we are beginning to comprehend the roles of S. epidermidis in balancing the epithelial microflora and serving as a reservoir of resistance genes. In this Review, I discuss the molecular basis of the commensal and infectious lifestyles of S. epidermidis.

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Figure 1: Biofilm development in Staphylococcus epidermidis.
Figure 2: The Staphylococcus epidermidis cell surface.
Figure 3: The exopolysaccharide poly-N-acetylglucosamine.
Figure 4: Phenol-soluble modulins.
Figure 5: The antimicrobial peptide sensor and regulator Aps.
Figure 6: Staphylococcus epidermidis as a commensal and infectious microorganism.

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References

  1. CDC. National Nosocomial Infections Surveillance (NNIS) system report, data summary from January 1992 through June 2004, issued October 2004. Am. J. Infect. Control 32, 470–485 (2004).

  2. Uckay, I. et al. Foreign body infections due to Staphylococcus epidermidis. Ann. Med. 41, 109–119 (2009).

    Article  CAS  PubMed  Google Scholar 

  3. Dimick, J. B. et al. Increased resource use associated with catheter-related bloodstream infection in the surgical intensive care unit. Arch. Surg. 136, 229–234 (2001).

    Article  CAS  PubMed  Google Scholar 

  4. Rello, J. et al. Evaluation of outcome of intravenous catheter-related infections in critically ill patients. Am. J. Respir. Crit. Care Med. 162, 1027–1030 (2000).

    Article  CAS  PubMed  Google Scholar 

  5. Rogers, K. L., Fey, P. D. & Rupp, M. E. Coagulase-negative staphylococcal infections. Infect. Dis. Clin. North Am. 23, 73–98 (2009). This provides an excellent review on clinical aspects of S. epidermidis infections.

    Article  PubMed  Google Scholar 

  6. Costerton, J. W., Stewart, P. S. & Greenberg, E. P. Bacterial biofilms: a common cause of persistent infections. Science 284, 1318–1322 (1999).

    Article  CAS  PubMed  Google Scholar 

  7. Kloos, W. & Schleifer, K. H. in Bergey's Manual of Systematic Bacteriology (eds Sneath, P. H. A., Mair, N., Sharpe, M. E. & Holt, J. G.) 1013–1035 (Williams & Wilkins, Baltimore, 1986).

    Google Scholar 

  8. Kloos, W. E. & Musselwhite, M. S. Distribution and persistence of Staphylococcus and Micrococcus species and other aerobic bacteria on human skin. Appl. Microbiol. 30, 381–385 (1975).

    CAS  PubMed  PubMed Central  Google Scholar 

  9. Gill, S. R. et al. Insights on evolution of virulence and resistance from the complete genome analysis of an early methicillin-resistant Staphylococcus aureus strain and a biofilm-producing methicillin-resistant Staphylococcus epidermidis strain. J. Bacteriol. 187, 2426–2438 (2005). This article describes the sequencing and comparison of the genomes of biofilm-forming S. epidermidis and S. aureus.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  10. Zhang, Y. Q. et al. Genome-based analysis of virulence genes in a non-biofilm-forming Staphylococcus epidermidis strain (ATCC 12228). Mol. Microbiol. 49, 1577–1593 (2003).

    Article  CAS  PubMed  Google Scholar 

  11. Wang, X. M. et al. Evaluation of a multilocus sequence typing system for Staphylococcus epidermidis. J. Med. Microbiol. 52, 989–998 (2003).

    Article  CAS  PubMed  Google Scholar 

  12. Wisplinghoff, H. et al. Related clones containing SCCmec type IV predominate among clinically significant Staphylococcus epidermidis isolates. Antimicrob. Agents Chemother. 47, 3574–3579 (2003).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  13. Thomas, J. C. et al. Improved multilocus sequence typing scheme for Staphylococcus epidermidis. J. Clin. Microbiol. 45, 616–619 (2007).

    Article  PubMed  Google Scholar 

  14. Miragaia, M., Thomas, J. C., Couto, I., Enright, M. C. & de Lencastre, H. Inferring a population structure for Staphylococcus epidermidis from multilocus sequence typing data. J. Bacteriol. 189, 2540–2552 (2007). This article details an investigation of the population structure of S. epidermidis.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  15. Li, M., Wang, X., Gao, Q. & Lu, Y. Molecular characterization of Staphylococcus epidermidis strains isolated from a teaching hospital in Shanghai, China. J. Med. Microbiol. 58, 456–461 (2009).

    Article  CAS  PubMed  Google Scholar 

  16. Galdbart, J. O., Allignet, J., Tung, H. S., Ryden, C. & El Solh, N. Screening for Staphylococcus epidermidis markers discriminating between skin-flora strains and those responsible for infections of joint prostheses. J. Infect. Dis. 182, 351–355 (2000).

    Article  CAS  PubMed  Google Scholar 

  17. Gu, J. et al. Bacterial insertion sequence IS256 as a potential molecular marker to discriminate invasive strains from commensal strains of Staphylococcus epidermidis. J. Hosp. Infect. 61, 342–348 (2005).

    Article  CAS  PubMed  Google Scholar 

  18. Kozitskaya, S. et al. The bacterial insertion sequence element IS256 occurs preferentially in nosocomial Staphylococcus epidermidis isolates: association with biofilm formation and resistance to aminoglycosides. Infect. Immun. 72, 1210–1215 (2004).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  19. Yao, Y. et al. Factors characterizing Staphylococcus epidermidis invasiveness determined by comparative genomics. Infect. Immun. 73, 1856–1860 (2005).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  20. Lina, G. et al. Bacterial competition for human nasal cavity colonization: role of staphylococcal agr alleles. Appl. Environ. Microbiol. 69, 18–23 (2003).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  21. O'Grady, N. P. et al. Guidelines for the prevention of intravascular catheter-related infections. MMWR Recomm. Rep. 51, 1–26 (2002).

    PubMed  Google Scholar 

  22. Chu, V. H. et al. Coagulase-negative staphylococcal prosthetic valve endocarditis — a contemporary update based on the International Collaboration on Endocarditis: prospective cohort study. Heart 95, 570–576 (2009).

    Article  CAS  PubMed  Google Scholar 

  23. Massey, R. C., Horsburgh, M. J., Lina, G., Hook, M. & Recker, M. The evolution and maintenance of virulence in Staphylococcus aureus: a role for host-to-host transmission? Nature Rev. Microbiol. 4, 953–958 (2006). This article reviews the mathematical model that explains the evolution of lifestyle differences between S. epidermidis and S. aureus.

    Article  CAS  Google Scholar 

  24. Otto, M., Sussmuth, R., Vuong, C., Jung, G. & Gotz, F. Inhibition of virulence factor expression in Staphylococcus aureus by the Staphylococcus epidermidis agr pheromone and derivatives. FEBS Lett. 450, 257–262 (1999).

    Article  CAS  PubMed  Google Scholar 

  25. Carmody, A. B. & Otto, M. Specificity grouping of the accessory gene regulator quorum-sensing system of Staphylococcus epidermidis is linked to infection. Arch. Microbiol. 181, 250–253 (2004).

    Article  CAS  PubMed  Google Scholar 

  26. Harder, J. & Schroder, J. M. Antimicrobial peptides in human skin. Chem. Immunol. Allergy 86, 22–41 (2005).

    Article  CAS  PubMed  Google Scholar 

  27. Faurschou, M. & Borregaard, N. Neutrophil granules and secretory vesicles in inflammation. Microbes Infect. 5, 1317–1327 (2003).

    Article  CAS  PubMed  Google Scholar 

  28. Pourmand, M. R., Clarke, S. R., Schuman, R. F., Mond, J. J. & Foster, S. J. Identification of antigenic components of Staphylococcus epidermidis expressed during human infection. Infect. Immun. 74, 4644–4654 (2006).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  29. Yao, Y., Sturdevant, D. E. & Otto, M. Genomewide analysis of gene expression in Staphylococcus epidermidis biofilms: insights into the pathophysiology of S. epidermidis biofilms and the role of phenol-soluble modulins in formation of biofilms. J. Infect. Dis. 191, 289–298 (2005). An investigation of genome-wide gene regulatory changes that occur in S. epidermidis biofilms.

    Article  CAS  PubMed  Google Scholar 

  30. Khardori, N., Yassien, M. & Wilson, K. Tolerance of Staphylococcus epidermidis grown from indwelling vascular catheters to antimicrobial agents. J. Ind. Microbiol. 15, 148–151 (1995).

    Article  CAS  PubMed  Google Scholar 

  31. Duguid, I. G., Evans, E., Brown, M. R. & Gilbert, P. Effect of biofilm culture upon the susceptibility of Staphylococcus epidermidis to tobramycin. J. Antimicrobiol. Chemother. 30, 803–810 (1992).

    Article  CAS  Google Scholar 

  32. Duguid, I. G., Evans, E., Brown, M. R. & Gilbert, P. Growth-rate-independent killing by ciprofloxacin of biofilm-derived Staphylococcus epidermidis; evidence for cell-cycle dependency. J. Antimicrobiol. Chemother. 30, 791–802 (1992).

    Article  CAS  Google Scholar 

  33. O'Toole, G., Kaplan, H. B. & Kolter, R. Biofilm formation as microbial development. Annu. Rev. Microbiol. 54, 49–79 (2000).

    Article  CAS  PubMed  Google Scholar 

  34. Vacheethasanee, K. et al. Bacterial surface properties of clinically isolated Staphylococcus epidermidis strains determine adhesion on polyethylene. J. Biomed. Mater. Res. 42, 425–432 (1998).

    Article  CAS  PubMed  Google Scholar 

  35. Heilmann, C., Hussain, M., Peters, G. & Gotz, F. Evidence for autolysin-mediated primary attachment of Staphylococcus epidermidis to a polystyrene surface. Mol. Microbiol. 24, 1013–1024 (1997).

    Article  CAS  PubMed  Google Scholar 

  36. Tormo, M. A., Knecht, E., Gotz, F., Lasa, I. & Penades, J. R. Bap-dependent biofilm formation by pathogenic species of Staphylococcus: evidence of horizontal gene transfer? Microbiology 151, 2465–2475 (2005).

    Article  CAS  PubMed  Google Scholar 

  37. Mazmanian, S. K., Liu, G., Ton-That, H. & Schneewind, O. Staphylococcus aureus sortase, an enzyme that anchors surface proteins to the cell wall. Science 285, 760–763 (1999).

    Article  CAS  PubMed  Google Scholar 

  38. Navarre, W. W. & Schneewind, O. Surface proteins of Gram-positive bacteria and mechanisms of their targeting to the cell wall envelope. Microbiol. Mol. Biol. Rev. 63, 174–229 (1999).

    CAS  PubMed  PubMed Central  Google Scholar 

  39. Arrecubieta, C., Lee, M. H., Macey, A., Foster, T. J. & Lowy, F. D. SdrF, a Staphylococcus epidermidis surface protein, binds type I collagen. J. Biol. Chem. 282, 18767–18776 (2007).

    Article  CAS  PubMed  Google Scholar 

  40. Hartford, O., O'Brien, L., Schofield, K., Wells, J. & Foster, T. J. The Fbe (SdrG) protein of Staphylococcus epidermidis HB promotes bacterial adherence to fibrinogen. Microbiology 147, 2545–2552 (2001).

    Article  CAS  PubMed  Google Scholar 

  41. Heilmann, C. et al. Identification and characterization of a novel autolysin (Aae) with adhesive properties from Staphylococcus epidermidis. Microbiology 149, 2769–2778 (2003).

    Article  CAS  PubMed  Google Scholar 

  42. McCrea, K. W. et al. The serine-aspartate repeat (Sdr) protein family in Staphylococcus epidermidis. Microbiology 146, 1535–1546 (2000).

    Article  CAS  PubMed  Google Scholar 

  43. Nilsson, M. et al. A fibrinogen-binding protein of Staphylococcus epidermidis. Infect. Immun. 66, 2666–2673 (1998).

    CAS  PubMed  PubMed Central  Google Scholar 

  44. Guo, B., Zhao, X., Shi, Y., Zhu, D. & Zhang, Y. Pathogenic implication of a fibrinogen-binding protein of Staphylococcus epidermidis in a rat model of intravascular-catheter-associated infection. Infect. Immun. 75, 2991–2995 (2007).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  45. Ponnuraj, K. et al. A “dock, lock, and latch” structural model for a staphylococcal adhesin binding to fibrinogen. Cell 115, 217–228 (2003). This work elucidated the mechanism by which SdrG binds to fibrinogen.

    Article  CAS  PubMed  Google Scholar 

  46. Sellman, B. R. et al. Expression of Staphylococcus epidermidis SdrG increases following exposure to an in vivo environment. Infect. Immun. 76, 2950–2957 (2008).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  47. Arrecubieta, C. et al. SdrF, a Staphylococcus epidermidis surface protein, contributes to the initiation of ventricular assist device driveline-related infections. PLoS Pathog. 5, e1000411 (2009).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  48. Bowden, M. G. et al. Identification and preliminary characterization of cell-wall-anchored proteins of Staphylococcus epidermidis. Microbiology 151, 1453–1464 (2005).

    Article  CAS  PubMed  Google Scholar 

  49. Gross, M., Cramton, S. E., Gotz, F. & Peschel, A. Key role of teichoic acid net charge in Staphylococcus aureus colonization of artificial surfaces. Infect. Immun. 69, 3423–3426 (2001).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  50. Sadovskaya, I., Vinogradov, E., Flahaut, S., Kogan, G. & Jabbouri, S. Extracellular carbohydrate-containing polymers of a model biofilm-producing strain, Staphylococcus epidermidis RP62A. Infect. Immun. 73, 3007–3017 (2005).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  51. Rice, K. C. et al. The cidA murein hydrolase regulator contributes to DNA release and biofilm development in Staphylococcus aureus. Proc. Natl Acad. Sci. USA 104, 8113–8118 (2007).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  52. Mack, D. et al. The intercellular adhesin involved in biofilm accumulation of Staphylococcus epidermidis is a linear β-1,6-linked glucosaminoglycan: purification and structural analysis. J. Bacteriol. 178, 175–183 (1996). This article details the structural characterization of the exopolysaccharide PNAG.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  53. Darby, C., Hsu, J. W., Ghori, N. & Falkow, S. Caenorhabditis elegans: plague bacteria biofilm blocks food intake. Nature 417, 243–244 (2002).

    Article  CAS  PubMed  Google Scholar 

  54. Wang, X., Preston, J. F. I. & Romeo, T. The pgaABCD locus of Escherichia coli promotes the synthesis of a polysaccharide adhesin required for biofilm formation. J. Bacteriol. 186, 2724–2734 (2004).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  55. Heilmann, C., Gerke, C., Perdreau-Remington, F. & Gotz, F. Characterization of Tn917 insertion mutants of Staphylococcus epidermidis affected in biofilm formation. Infect. Immun. 64, 277–282 (1996).

    CAS  PubMed  PubMed Central  Google Scholar 

  56. Heilmann, C. et al. Molecular basis of intercellular adhesion in the biofilm-forming Staphylococcus epidermidis. Mol. Microbiol. 20, 1083–1091 (1996). This work identified the genetic locus that governs PNAG biosynthesis.

    Article  CAS  PubMed  Google Scholar 

  57. Francois, P. et al. Lack of biofilm contribution to bacterial colonisation in an experimental model of foreign body infection by Staphylococcus aureus and Staphylococcus epidermidis. FEMS Immunol. Med. Microbiol. 35, 135–140 (2003).

    Article  CAS  PubMed  Google Scholar 

  58. Rupp, M. E., Ulphani, J. S., Fey, P. D., Bartscht, K. & Mack, D. Characterization of the importance of polysaccharide intercellular adhesin/hemagglutinin of Staphylococcus epidermidis in the pathogenesis of biomaterial-based infection in a mouse foreign body infection model. Infect. Immun. 67, 2627–2632 (1999). This was the first in vivo analysis of an S. epidermidis virulence determinant (PNAG) using an isogenic mutant.

    CAS  PubMed  PubMed Central  Google Scholar 

  59. Rupp, M. E., Ulphani, J. S., Fey, P. D. & Mack, D. Characterization of Staphylococcus epidermidis polysaccharide intercellular adhesin/hemagglutinin in the pathogenesis of intravascular catheter-associated infection in a rat model. Infect. Immun. 67, 2656–2659 (1999).

    CAS  PubMed  PubMed Central  Google Scholar 

  60. Chokr, A., Leterme, D., Watier, D. & Jabbouri, S. Neither the presence of ica locus, nor in vitro-biofilm formation ability is a crucial parameter for some Staphylococcus epidermidis strains to maintain an infection in a guinea pig tissue cage model. Microb. Pathog. 42, 94–97 (2007).

    Article  CAS  PubMed  Google Scholar 

  61. Fluckiger, U. et al. Biofilm formation, icaADBC transcription, and polysaccharide intercellular adhesin synthesis by staphylococci in a device-related infection model. Infect. Immun. 73, 1811–1819 (2005).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  62. Gerke, C., Kraft, A., Sussmuth, R., Schweitzer, O. & Gotz, F. Characterization of the N-acetylglucosaminyltransferase activity involved in the biosynthesis of the Staphylococcus epidermidis polysaccharide intercellular adhesin. J. Biol. Chem. 273, 18586–18593 (1998). This article describes the identification of the biochemical function of the IcaA and IcaD proteins.

    Article  CAS  PubMed  Google Scholar 

  63. Vuong, C. et al. A crucial role for exopolysaccharide modification in bacterial biofilm formation, immune evasion, and virulence. J. Biol. Chem. 279, 54881–54886 (2004). This study identified the biochemical function of the IcaB PNAG de-acetylase and showed its role in vitro and in vivo.

    Article  CAS  PubMed  Google Scholar 

  64. O'Gara, J. P. ica and beyond: biofilm mechanisms and regulation in Staphylococcus epidermidis and Staphylococcus aureus. FEMS Microbiol. Lett. 270, 179–188 (2007).

    Article  CAS  PubMed  Google Scholar 

  65. Ziebuhr, W. et al. A novel mechanism of phase variation of virulence in Staphylococcus epidermidis: evidence for control of the polysaccharide intercellular adhesin synthesis by alternating insertion and excision of the insertion sequence element IS256. Mol. Microbiol. 32, 345–356 (1999).

    Article  CAS  PubMed  Google Scholar 

  66. Knobloch, J. K. et al. Biofilm formation by Staphylococcus epidermidis depends on functional RsbU, an activator of the sigB operon: differential activation mechanisms due to ethanol and salt stress. J. Bacteriol. 183, 2624–2633 (2001).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  67. Mack, D. et al. Identification of three essential regulatory gene loci governing expression of Staphylococcus epidermidis polysaccharide intercellular adhesin and biofilm formation. Infect. Immun. 68, 3799–3807 (2000).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  68. Tormo, M. A. et al. SarA is an essential positive regulator of Staphylococcus epidermidis biofilm development. J. Bacteriol. 187, 2348–2356 (2005).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  69. Handke, L. D. et al. σB and SarA independently regulate polysaccharide intercellular adhesin production in Staphylococcus epidermidis. Can. J. Microbiol. 53, 82–91 (2007).

    Article  CAS  PubMed  Google Scholar 

  70. Al Laham, N. et al. Augmented expression of polysaccharide intercellular adhesin in a defined Staphylococcus epidermidis mutant with the small-colony-variant phenotype. J. Bacteriol. 189, 4494–4501 (2007).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  71. Xu, L. et al. Role of the luxS quorum-sensing system in biofilm formation and virulence of Staphylococcus epidermidis. Infect. Immun. 74, 488–496 (2006).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  72. Vuong, C., Gerke, C., Somerville, G. A., Fischer, E. R. & Otto, M. Quorum-sensing control of biofilm factors in Staphylococcus epidermidis. J. Infect. Dis. 188, 706–718 (2003).

    Article  CAS  PubMed  Google Scholar 

  73. Kogan, G., Sadovskaya, I., Chaignon, P., Chokr, A. & Jabbouri, S. Biofilms of clinical strains of Staphylococcus that do not contain polysaccharide intercellular adhesin. FEMS Microbiol. Lett. 255, 11–16 (2006).

    Article  CAS  PubMed  Google Scholar 

  74. Rohde, H. et al. Polysaccharide intercellular adhesin or protein factors in biofilm accumulation of Staphylococcus epidermidis and Staphylococcus aureus isolated from prosthetic hip and knee joint infections. Biomaterials 28, 1711–1720 (2007). This article gives an exceptionally balanced view of the roles of proteins versus exopolysaccharide in S. epidermis biofilm formation, in contrast to several reports that point to the importance of protein-mediated biofilm formation.

    Article  CAS  PubMed  Google Scholar 

  75. Hussain, M., Herrmann, M., von Eiff, C., Perdreau-Remington, F. & Peters, G. A 140-kilodalton extracellular protein is essential for the accumulation of Staphylococcus epidermidis strains on surfaces. Infect. Immun. 65, 519–524 (1997).

    CAS  PubMed  PubMed Central  Google Scholar 

  76. Rohde, H. et al. Induction of Staphylococcus epidermidis biofilm formation via proteolytic processing of the accumulation-associated protein by staphylococcal and host proteases. Mol. Microbiol. 55, 1883–1895 (2005).

    Article  CAS  PubMed  Google Scholar 

  77. Conrady, D. G. et al. A zinc-dependent adhesion module is responsible for intercellular adhesion in staphylococcal biofilms. Proc. Natl Acad. Sci. USA 105, 19456–19461 (2008). This work shed light on the mechanism of Aap self-aggregation.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  78. Banner, M. A. et al. Localized tufts of fibrils on Staphylococcus epidermidis NCTC 11047 are comprised of the accumulation-associated protein. J. Bacteriol. 189, 2793–2804 (2007).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  79. Bateman, A., Holden, M. T. & Yeats, C. The G5 domain: a potential N-acetylglucosamine recognition domain involved in biofilm formation. Bioinformatics 21, 1301–1303 (2005).

    Article  CAS  PubMed  Google Scholar 

  80. Sun, D., Accavitti, M. A. & Bryers, J. D. Inhibition of biofilm formation by monoclonal antibodies against Staphylococcus epidermidis RP62A accumulation-associated protein. Clin. Diagn. Lab. Immunol. 12, 93–100 (2005).

    CAS  PubMed  PubMed Central  Google Scholar 

  81. Conlon, K. M., Humphreys, H. & O'Gara, J. P. Inactivations of rsbU and sarA by IS256 represent novel mechanisms of biofilm phenotypic variation in Staphylococcus epidermidis. J. Bacteriol. 186, 6208–6219 (2004).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  82. Chaignon, P. et al. Susceptibility of staphylococcal biofilms to enzymatic treatments depends on their chemical composition. Appl. Microbiol. Biotechnol. 75, 125–132 (2007).

    Article  CAS  PubMed  Google Scholar 

  83. Vuong, C., Kocianova, S., Yao, Y., Carmody, A. B. & Otto, M. Increased colonization of indwelling medical devices by quorum-sensing mutants of Staphylococcus epidermidis in vivo. J. Infect. Dis. 190, 1498–1505 (2004). This manuscript shows the role of the S. epidermidis agr quorum sensing regulator in vivo.

    Article  PubMed  Google Scholar 

  84. Yarwood, J. M., Bartels, D. J., Volper, E. M. & Greenberg, E. P. Quorum sensing in Staphylococcus aureus biofilms. J. Bacteriol. 186, 1838–1850 (2004).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  85. Boles, B. R. & Horswill, A. R. Agr-mediated dispersal of Staphylococcus aureus biofilms. PLoS Pathog. 4, e1000052 (2008).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  86. Teufel, P. & Gotz, F. Characterization of an extracellular metalloprotease with elastase activity from Staphylococcus epidermidis. J. Bacteriol. 175, 4218–4224 (1993).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  87. Dubin, G. et al. Molecular cloning and biochemical characterisation of proteases from Staphylococcus epidermidis. Biol. Chem. 382, 1575–1582 (2001).

    Article  CAS  PubMed  Google Scholar 

  88. Ohara-Nemoto, Y. et al. Characterization and molecular cloning of a glutamyl endopeptidase from Staphylococcus epidermidis. Microb. Pathog. 33, 33–41 (2002).

    Article  CAS  PubMed  Google Scholar 

  89. Kaplan, J. B. et al. Genes involved in the synthesis and degradation of matrix polysaccharide in Actinobacillus actinomycetemcomitans and Actinobacillus pleuropneumoniae biofilms. J. Bacteriol. 186, 8213–8220 (2004).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  90. Kaplan, J. B., Ragunath, C., Ramasubbu, N. & Fine, D. H. Detachment of Actinobacillus actinomycetemcomitans biofilm cells by an endogenous β-hexosaminidase activity. J. Bacteriol. 185, 4693–4698 (2003).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  91. Kong, K. F., Vuong, C. & Otto, M. Staphylococcus quorum sensing in biofilm formation and infection. Int. J. Med. Microbiol. 296, 133–139 (2006).

    Article  CAS  PubMed  Google Scholar 

  92. Vuong, C. et al. Regulated expression of pathogen-associated molecular pattern molecules in Staphylococcus epidermidis: quorum-sensing determines pro-inflammatory capacity and production of phenol-soluble modulins. Cell. Microbiol. 6, 753–759 (2004).

    Article  CAS  PubMed  Google Scholar 

  93. Yao, Y. et al. Characterization of the Staphylococcus epidermidis accessory-gene regulator response: quorum-sensing regulation of resistance to human innate host defence. J. Infect. Dis. 193, 841–848 (2006).

    Article  PubMed  Google Scholar 

  94. Kocianova, S. et al. Key role of poly-γ-DL-glutamic acid in immune evasion and virulence of Staphylococcus epidermidis. J. Clin. Invest. 115, 688–694 (2005). This article investigates the role of poly-γ- DL -glutamic acid in S. epidermidis.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  95. Little, S. F. & Ivins, B. E. Molecular pathogenesis of Bacillus anthracis infection. Microbes Infect. 1, 131–139 (1999).

    Article  CAS  PubMed  Google Scholar 

  96. Oppermann-Sanio, F. B. & Steinbuchel, A. Occurrence, functions and biosynthesis of polyamides in microorganisms and biotechnological production. Naturwissenschaften 89, 11–22 (2002).

    Article  PubMed  Google Scholar 

  97. Kristian, S. A. et al. Biofilm formation induces C3a release and protects Staphylococcus epidermidis from IgG and complement deposition and from neutrophil-dependent killing. J. Infect. Dis. 197, 1028–1035 (2008).

    Article  PubMed  Google Scholar 

  98. Vuong, C. et al. Polysaccharide intercellular adhesin (PIA) protects Staphylococcus epidermidis against major components of the human innate immune system. Cell. Microbiol. 6, 269–275 (2004). This study shows the important role of PNAG in immune evasion.

    Article  CAS  PubMed  Google Scholar 

  99. Begun, J. et al. Staphylococcal biofilm exopolysaccharide protects against Caenorhabditis elegans immune defences. PLoS Pathog. 3, e57 (2007).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  100. Mah, T. F. et al. A genetic basis for Pseudomonas aeruginosa biofilm antibiotic resistance. Nature 426, 306–310 (2003).

    Article  CAS  PubMed  Google Scholar 

  101. Heine, H. & Ulmer, A. J. Recognition of bacterial products by Toll-like receptors. Chem. Immunol. Allergy 86, 99–119 (2005).

    Article  CAS  PubMed  Google Scholar 

  102. Stevens, N. T. et al. Staphylococcus epidermidis polysaccharide intercellular adhesin induces IL-8 expression in human astrocytes via a mechanism involving TLR2. Cell. Microbiol. 11, 421–432 (2008).

    Article  CAS  PubMed  Google Scholar 

  103. Henneke, P. et al. Lipoproteins are critical TLR2 activating toxins in group B streptococcal sepsis. J. Immunol. 180, 6149–6158 (2008).

    Article  CAS  PubMed  Google Scholar 

  104. Li, H., Nooh, M. M., Kotb, M. & Re, F. Commercial peptidoglycan preparations are contaminated with superantigen-like activity that stimulates IL-17 production. J. Leukoc. Biol. 83, 409–418 (2008).

    Article  CAS  PubMed  Google Scholar 

  105. Hashimoto, M. et al. Not lipoteichoic acid but lipoproteins appear to be the dominant immunobiologically active compounds in Staphylococcus aureus. J. Immunol. 177, 3162–3169 (2006).

    Article  CAS  PubMed  Google Scholar 

  106. Mehlin, C., Headley, C. M. & Klebanoff, S. J. An inflammatory polypeptide complex from Staphylococcus epidermidis: isolation and characterization. J. Exp. Med. 189, 907–918 (1999). This article describes the identification and pro-inflammatory properties of the main S. epidermidis PSMs.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  107. Wang, R. et al. Identification of novel cytolytic peptides as key virulence determinants for community-associated MRSA. Nature Med. 13, 1510–1514 (2007).

    Article  CAS  PubMed  Google Scholar 

  108. Hajjar, A. M. et al. Cutting edge: functional interactions between Toll-like receptor (TLR) 2 and TLR1 or TLR6 in response to phenol-soluble modulin. J. Immunol. 166, 15–19 (2001).

    Article  CAS  PubMed  Google Scholar 

  109. Lambert, P. A., Worthington, T., Tebbs, S. E. & Elliott, T. S. Lipid S, a novel Staphylococcus epidermidis exocellular antigen with potential for the serodiagnosis of infections. FEMS Immunol. Med. Microbiol. 29, 195–202 (2000).

    Article  CAS  PubMed  Google Scholar 

  110. Li, M. et al. Gram-positive three-component antimicrobial peptide-sensing system. Proc. Natl Acad. Sci. USA 104, 9469–9474 (2007). This work identified and characterized the first Gram-positive AMP sensor in S. epidermidis.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  111. Peschel, A. et al. Inactivation of the dlt operon in Staphylococcus aureus confers sensitivity to defensins, protegrins, and other antimicrobial peptides. J. Biol. Chem. 274, 8405–8410 (1999).

    Article  CAS  PubMed  Google Scholar 

  112. Peschel, A. et al. Staphylococcus aureus resistance to human defensins and evasion of neutrophil killing via the novel virulence factor MprF is based on modification of membrane lipids with L-lysine. J. Exp. Med. 193, 1067–1076 (2001).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  113. Li, M. et al. The antimicrobial peptide-sensing system aps of Staphylococcus aureus. Mol. Microbiol. 66, 1136–1147 (2007).

    Article  CAS  PubMed  Google Scholar 

  114. Bader, M. W. et al. Recognition of antimicrobial peptides by a bacterial sensor kinase. Cell 122, 461–472 (2005).

    Article  CAS  PubMed  Google Scholar 

  115. Marin, M. E., de la Rosa, M. C. & Cornejo, I. Enterotoxigenicity of Staphylococcus strains isolated from Spanish dry-cured hams. Appl. Environ. Microbiol. 58, 1067–1069 (1992).

    CAS  PubMed  PubMed Central  Google Scholar 

  116. Bautista, L., Gaya, P., Medina, M. & Nunez, M. A quantitative study of enterotoxin production by sheep milk staphylococci. Appl. Environ. Microbiol. 54, 566–569 (1988).

    CAS  PubMed  PubMed Central  Google Scholar 

  117. Klingenberg, C. et al. Persistent strains of coagulase-negative staphylococci in a neonatal intensive care unit: virulence factors and invasiveness. Clin. Microbiol. Infect. 13, 1100–1111 (2007).

    Article  CAS  PubMed  Google Scholar 

  118. Scheifele, D. W., Bjornson, G. L., Dyer, R. A. & Dimmick, J. E. Delta-like toxin produced by coagulase-negative staphylococci is associated with neonatal necrotizing enterocolitis. Infect. Immun. 55, 2268–2273 (1987).

    CAS  PubMed  PubMed Central  Google Scholar 

  119. Rohde, H. et al. Detection of virulence-associated genes not useful for discriminating between invasive and commensal Staphylococcus epidermidis strains from a bone marrow transplant unit. J. Clin. Microbiol. 42, 5614–5619 (2004).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  120. Ziebuhr, W. et al. Modulation of the polysaccharide intercellular adhesin (PIA) expression in biofilm forming Staphylococcus epidermidis. Analysis of genetic mechanisms. Adv. Exp. Med. Biol. 485, 151–157 (2000).

    Article  CAS  PubMed  Google Scholar 

  121. Rogers, K. L., Rupp, M. E. & Fey, P. D. The presence of icaADBC is detrimental to the colonization of human skin by Staphylococcus epidermidis. Appl. Environ. Microbiol. 74, 6155–6157 (2008).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  122. Lai, Y. et al. The human anionic antimicrobial peptide dermcidin induces proteolytic defence mechanisms in staphylococci. Mol. Microbiol. 63, 497–506 (2007).

    Article  CAS  PubMed  Google Scholar 

  123. Diekema, D. J. et al. Survey of infections due to Staphylococcus species: frequency of occurrence and antimicrobial susceptibility of isolates collected in the United States, Canada, Latin America, Europe, and the Western Pacific region for the SENTRY Antimicrobial Surveillance Program, 1997–1999. Clin. Infect. Dis. 32, S114–S132 (2001).

    Article  CAS  PubMed  Google Scholar 

  124. Vos, M. C., Ott, A. & Verbrugh, H. A. Successful search-and-destroy policy for methicillin-resistant Staphylococcus aureus in The Netherlands. J. Clin. Microbiol. 43, 2034; author reply 2034–2035 (2005).

    Article  PubMed  PubMed Central  Google Scholar 

  125. van Pelt, C. et al. Strict infection control measures do not prevent clonal spread of coagulase negative staphylococci colonizing central venous catheters in neutropenic hemato-oncologic patients. FEMS Immunol. Med. Microbiol. 38, 153–158 (2003).

    Article  CAS  PubMed  Google Scholar 

  126. Chambers, H. F., Hartman, B. J. & Tomasz, A. Increased amounts of a novel penicillin-binding protein in a strain of methicillin-resistant Staphylococcus aureus exposed to nafcillin. J. Clin. Invest. 76, 325–331 (1985).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  127. Ma, X. X. et al. Novel type of staphylococcal cassette chromosome mec identified in community-acquired methicillin-resistant Staphylococcus aureus strains. Antimicrob. Agents Chemother. 46, 1147–1152 (2002).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  128. Miragaia, M., Couto, I. & de Lencastre, H. Genetic diversity among methicillin-resistant Staphylococcus epidermidis (MRSE). Microb. Drug Resist. 11, 83–93 (2005).

    Article  CAS  PubMed  Google Scholar 

  129. Diep, B. A. et al. The arginine catabolic mobile element and staphylococcal chromosomal cassette mec linkage: convergence of virulence and resistance in the USA300 clone of methicillin-resistant Staphylococcus aureus. J. Infect. Dis. 197, 1523–1530 (2008).

    Article  CAS  PubMed  Google Scholar 

  130. Miragaia, M. et al. Molecular characterization of methicillin-resistant Staphylococcus epidermidis clones: evidence of geographic dissemination. J. Clin. Microbiol. 40, 430–438 (2002).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  131. Raad, I., Hanna, H. & Maki, D. Intravascular catheter-related infections: advances in diagnosis, prevention, and management. Lancet Infect. Dis. 7, 645–657 (2007).

    Article  PubMed  Google Scholar 

  132. Schwalbe, R. S., Stapleton, J. T. & Gilligan, P. H. Emergence of vancomycin resistance in coagulase-negative staphylococci. N. Engl. J. Med. 316, 927–931 (1987).

    Article  CAS  PubMed  Google Scholar 

  133. Gagnon, R. F., Richards, G. K. & Subang, R. Vancomycin therapy of experimental peritoneal catheter-associated infection (Staphylococcus epidermidis) in a mouse model. Perit. Dial. Int. 13 (Suppl. 2), 310–312 (1993).

    Google Scholar 

  134. Richards, G. K., Prentis, J. & Gagnon, R. F. Antibiotic activity against Staphylococcus epidermidis biofilms in dialysis fluids. Adv. Perit. Dial. 5, 133–137 (1989).

    CAS  PubMed  Google Scholar 

  135. Raad, I. et al. Comparative activities of daptomycin, linezolid, and tigecycline against catheter-related methicillin-resistant Staphylococcus bacteremic isolates embedded in biofilm. Antimicrob. Agents Chemother. 51, 1656–1660 (2007).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  136. Hanssen, A. M., Kjeldsen, G. & Sollid, J. U. Local variants of staphylococcal cassette chromosome mec in sporadic methicillin-resistant Staphylococcus aureus and methicillin-resistant coagulase-negative staphylococci: evidence of horizontal gene transfer? Antimicrob. Agents Chemother. 48, 285–296 (2004).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  137. Chambers, H. F. The changing epidemiology of Staphylococcus aureus? Emerg. Infect. Dis. 7, 178–182 (2001).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  138. Diep, B. A. et al. Complete genome sequence of USA300, an epidemic clone of community-acquired meticillin-resistant Staphylococcus aureus. Lancet 367, 731–739 (2006).

    Article  CAS  PubMed  Google Scholar 

  139. DeLeo, F. R. & Otto, M. An antidote for Staphylococcus aureus pneumonia? J. Exp. Med. 205, 271–274 (2008).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  140. Otto, M. Targeted immunotherapy for staphylococcal infections: focus on anti-MSCRAMM antibodies. BioDrugs 22, 27–36 (2008).

    Article  CAS  PubMed  Google Scholar 

  141. Marraffini, L. A. & Sontheimer, E. J. CRISPR interference limits horizontal gene transfer in staphylococci by targeting DNA. Science 322, 1843–1845 (2008). This article describes the functional characterization of CRISPR sequences in S. epidermidis.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  142. Rupp, M. E., Fey, P. D., Heilmann, C. & Gotz, F. Characterization of the importance of Staphylococcus epidermidis autolysin and polysaccharide intercellular adhesin in the pathogenesis of intravascular catheter-associated infection in a rat model. J. Infect. Dis. 183, 1038–1042 (2001).

    Article  CAS  PubMed  Google Scholar 

  143. Pintens, V. et al. The role of σB in persistence of Staphylococcus epidermidis foreign body infection. Microbiology 154, 2827–2836 (2008).

    Article  CAS  PubMed  Google Scholar 

  144. Vandecasteele, S. J., Peetermans, W. E., Merckx, R. & Van Eldere, J. Expression of biofilm-associated genes in Staphylococcus epidermidis during in vitro and in vivo foreign body infections. J. Infect. Dis. 188, 730–737 (2003).

    Article  CAS  PubMed  Google Scholar 

  145. Vuong, C., Kocianova, S., Yu, J., Kadurugamuwa, J. L. & Otto, M. Development of real-time in vivo imaging of device-related Staphylococcus epidermidis infection in mice and influence of animal immune status on susceptibility to infection. J. Infect. Dis. 198, 258–261 (2008).

    Article  PubMed  Google Scholar 

  146. Novick, R. P. & Geisinger, E. Quorum sensing in staphylococci. Annu. Rev. Genet. 42, 541–564 (2008).

    Article  CAS  PubMed  Google Scholar 

  147. Novick, R. P. et al. Synthesis of staphylococcal virulence factors is controlled by a regulatory RNA molecule. EMBO J. 12, 3967–3975 (1993).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  148. Queck, S. Y. et al. RNAIII-independent target gene control by the agr quorum-sensing system: insight into the evolution of virulence regulation in Staphylococcus aureus. Mol. Cell 32, 150–158 (2008).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  149. Mayville, P. et al. Structure–activity analysis of synthetic autoinducing thiolactone peptides from Staphylococcus aureus responsible for virulence. Proc. Natl Acad. Sci. USA 96, 1218–1223 (1999).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  150. Otto, M., Sussmuth, R., Jung, G. & Gotz, F. Structure of the pheromone peptide of the Staphylococcus epidermidis agr system. FEBS Lett. 424, 89–94 (1998).

    Article  CAS  PubMed  Google Scholar 

  151. Otto, M. Staphylococcus aureus and Staphylococcus epidermidis peptide pheromones produced by the accessory gene regulator agr system. Peptides 22, 1603–1608 (2001).

    Article  CAS  PubMed  Google Scholar 

  152. Otto, M., Echner, H., Voelter, W. & Gotz, F. Pheromone cross-inhibition between Staphylococcus aureus and Staphylococcus epidermidis. Infect. Immun. 69, 1957–1960 (2001).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  153. Vuong, C., Gotz, F. & Otto, M. Construction and characterization of an agr deletion mutant of Staphylococcus epidermidis. Infect. Immun. 68, 1048–1053 (2000).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  154. Simons, J. W. et al. Cloning, purification and characterisation of the lipase from Staphylococcus epidermidis — comparison of the substrate selectivity with those of other microbial lipases. Eur. J. Biochem. 253, 675–683 (1998).

    Article  CAS  PubMed  Google Scholar 

  155. Farrell, A. M., Foster, T. J. & Holland, K. T. Molecular analysis and expression of the lipase of Staphylococcus epidermidis. J. Gen. Microbiol. 139, 267–277 (1993).

    Article  CAS  PubMed  Google Scholar 

  156. Longshaw, C. M., Farrell, A. M., Wright, J. D. & Holland, K. T. Identification of a second lipase gene, gehD, in Staphylococcus epidermidis: comparison of sequence with those of other staphylococcal lipases. Microbiology 146, 1419–1427 (2000).

    Article  CAS  PubMed  Google Scholar 

  157. Lindsay, J. A., Riley, T. V. & Mee, B. J. Production of siderophore by coagulase-negative staphylococci and its relation to virulence. Eur. J. Clin. Microbiol. Infect. Dis. 13, 1063–1066 (1994).

    Article  CAS  PubMed  Google Scholar 

  158. Cotton, J. L., Tao, J. & Balibar, C. J. Identification and characterization of the Staphylococcus aureus gene cluster coding for staphyloferrin A. Biochemistry 48, 1025–1035 (2009).

    Article  CAS  PubMed  Google Scholar 

  159. Cockayne, A. et al. Molecular cloning of a 32-kilodalton lipoprotein component of a novel iron-regulated Staphylococcus epidermidis ABC transporter. Infect. Immun. 66, 3767–3774 (1998).

    CAS  PubMed  PubMed Central  Google Scholar 

  160. Chamberlain, N. R. & Brueggemann, S. A. Characterisation and expression of fatty acid modifying enzyme produced by Staphylococcus epidermidis. J. Med. Microbiol. 46, 693–697 (1997).

    Article  CAS  PubMed  Google Scholar 

  161. Park, P. W., Rosenbloom, J., Abrams, W. R., Rosenbloom, J. & Mecham, R. P. Molecular cloning and expression of the gene for elastin-binding protein (ebpS) in Staphylococcus aureus. J. Biol. Chem. 271, 15803–15809 (1996).

    Article  CAS  PubMed  Google Scholar 

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Acknowledgements

This work was supported by the intramural research programme of the National Institute of Allergy and Infectious Diseases.

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  1. National Institute of Allergy and Infectious Diseases, The National Institutes of Health, 9000 Rockville Pike Building 33 1W10, Bethesda, 20892, Maryland, USA

    Michael Otto

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DATABASES

Entrez Genome Project

Bacillus anthracis

Caenorhabditis elegans

Escherichia coli

Pseudomonas aeruginosa

Staphylococcus aureus

S. epidermidis ATCC 12228

S. epidermidis RP62A

Yersinia pestis

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Glossary

Biofilm

A multicellular agglomeration of microorganisms that forms on a surface. Biofilms have a characteristic three-dimensional structure and physiology.

Quorum sensing

A method of cell density-dependent gene regulation in bacteria. Quorum sensing systems in Gram-positive bacteria commonly contain peptide-based secreted signals and a membrane-located sensor. The staphylococcal quorum sensing system is termed agr and controls a series of genes involved in metabolism and virulence.

Antimicrobial peptide

A peptide such as a defensin or cathelicidin, which have antimicrobial activity. Antimicrobial peptides are secreted by the host, for example, by epithelial cells or into neutrophil phagosomes.

Innate host defence

A part of the immune system that provides the first line of defence, a fast response to invading microorganisms, based on recognition of pathogen-associated molecular patterns. The innate immune system consists mainly of phagocytes, platelets and secreted antimicrobial peptides.

Neutrophil

The most abundant leukocyte in human blood. Neutrophils are the main cells that eliminate invading microorganisms by uptake and subsequent killing through reactive oxygen species and antimicrobial proteins and peptides.

Acquired host defence

A part of the immune system that depends on antigen-dependent clonal expansion of T and B cells after antigen presentation by professional antigen-presenting cells. The acquired response provides long-term humoral (antibody-based) and cell-mediated immunity, but is delayed.

Sortase

An enzyme that covalently links secreted bacterial surface proteins to peptidoglycan. Most of these proteins are substrates of sortase A and are characterized by an LPXTG amino acid motif at the carboxyl terminus.

Teichoic acid

An anionic cell envelope glycopolymer produced by Gram-positive bacteria, composed of many identical sugar–phosphate-repeating units. Teichoic acids can be linked to peptidoglycan (wall teichoic acids) or to the cytoplasmic membrane through a lipid anchor (lipoteichoic acids).

Pseudopeptide

A peptide that is formed by peptide bonds through carboxyl groups other than the α-carboxyl group.

Pathogen-associated molecular pattern

A surface structure on pathogens that is recognized by the innate immune system as non-self and triggers activation of innate host defence, usually by binding to Toll-like receptors.

Two-component system

A bacterial sensory system composed of a membrane-located sensor (histidine kinase) and a cytoplasmic DNA-binding regulatory protein (response regulator). The autophosphorylation-dependent activation of two-component systems is triggered by an extracellular signal.

Enterotoxin

A protein toxin released by a microorganism into the intestine of its host.

Methicillin

A penicillin derivative that is resistant to penicillinase (an enzyme widespread in staphylococci that provides resistance to penicillin).

Mobile genetic element

DNA such as a plasmid or transposon that can be exchanged between bacteria by horizontal gene transfer. Mobile genetic elements often carry virulence or antibiotic resistance genes.

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Otto, M. Staphylococcus epidermidis — the 'accidental' pathogen. Nat Rev Microbiol 7, 555–567 (2009). https://doi.org/10.1038/nrmicro2182

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