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PROSITE documentation PDOC00552

Gram-negative pili assembly chaperone signature


Most Gram-negative bacteria possess a supramolecular structure - the pili - on their surface, that mediates attachment to specific receptors. The assembly of the pili requires the help of specialized periplasmic chaperones [1,2,3]. These proteins are structurally and possibly evolutionary related to the immunoglobulin family. Known members of this family are listed below:

  • Escherichia coli papD for P pili.
  • Escherichia coli afaB for AFA-III adhesin.
  • Escherichia coli aggD for AAF/I fimbriae.
  • Escherichia coli cssC for CS6 antigen.
  • Escherichia coli F17-D for F17 pili.
  • Escherichia coli faeE for K88 pili.
  • Escherichia coli fanE for K99 pili.
  • Escherichia coli fimC for type 1 fimbriae.
  • Escherichia coli focC for F1C fimbriae.
  • Escherichia coli nfaE for NFA-I adhesin.
  • Escherichia coli sfaE for S pili.
  • Escherichia coli clpE for CS31A capsule-like antigen.
  • Escherichia coli ecpD for a yet unknown pilin.
  • Escherichia coli CS3-1 for CS3 pili.
  • Bordetella pertussis fhaD (or fimB) for filamentous hemagglutinin and fimbria.
  • Haemophilus influenzae hifB for type b pili.
  • Klebsiella pneumoniae mrkB for type 3 pili.
  • Proteus mirabilis pmfD for PMF fimbriae.
  • Salmonella enteritidis sefB for sef14 fimbriae.
  • Salmonella typhimurium lpfB for long polar fimbriae.
  • Yersinia enterocolitica myfB for myf fimbriae.
  • Yersinia pestis caf1M for F1 capsule antigen.
  • Yersinia pestis psaB for pH6 antigen.
  • Escherichia coli hypothetical protein ybgP.
  • Escherichia coli hypothetical protein ycbF.
  • Escherichia coli hypothetical protein yehC.
  • Escherichia coli hypothetical protein yfcS.
  • Escherichia coli hypothetical protein yhcA.
  • Escherichia coli hypothetical protein yqiH.
  • Escherichia coli hypothetical protein yraI.

Structurally, these proteins consist of two globular domains with a topology identical to an immunoglobulin fold. As a signature pattern, we selected a highly conserved region located in the C-terminal section of the first globular domain.

Last update:

December 2004 / Pattern and text revised.

Technical section

PROSITE method (with tools and information) covered by this documentation:

PILI_CHAPERONE, PS00635; Gram-negative pili assembly chaperone signature  (PATTERN)


1AuthorsHung D.L., Knight S.D., Woods R.M., Pinkner J.S., Hultgren S.J.
TitleMolecular basis of two subfamilies of immunoglobulin-like chaperones.
SourceEMBO J. 15:3792-3805(1996).
PubMed ID8670884

2AuthorsJacob-Dubuisson F., Kuehn M.J., Hultgren S.J.
SourceTrends Microbiol. 1:50-55(1993).

3Authorsvan Rosmalen M., Saier M.H. Jr.
SourceRes. Microbiol. 144:507-527(1993).

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