3F84

Structure of fusion complex of major pilin CfaB and major pilin CfaB of CFA/I pilus from ETEC E. coli

Summary for 3F84

• Entry DOI: 10.2210/pdb3f84/pdb
• Related: 2HB0 3F83 3F85
• Descriptor: CFA/I fimbrial subunit B (2 entities in total)
• Functional Keywords: etec, cfa/i, fimbriae, pilus, e. coli, diarrhea, cfabb, cell projection, fimbrium, cell adhesion
• Biological source: Escherichia coli; More
• Total number of polymer chains: 2
• Total formula weight: 64904.94

Authors

Xia, D.,Li, Y.F. (deposition date: 2008-11-11, release date: 2009-08-11, Last modification date: 2023-12-27)

Primary citation

Li, Y.F.,Poole, S.,Nishio, K.,Jang, K.,Rasulova, F.,McVeigh, A.,Savarino, S.J.,Xia, D.,Bullitt, E.
Structure of CFA/I fimbriae from enterotoxigenic Escherichia coli.
Proc.Natl.Acad.Sci.USA, 106:10793-10798, 2009

PubMed Abstract: Adhesion pili (fimbriae) play a critical role in initiating the events that lead to intestinal colonization and diarrheal disease by enterotoxigenic Escherichia coli (ETEC), an E. coli pathotype that inflicts an enormous global disease burden. We elucidate atomic structures of an ETEC major pilin subunit, CfaB, from colonization factor antigen I (CFA/I) fimbriae. These data are used to construct models for 2 morphological forms of CFA/I fimbriae that are both observed in vivo: the helical filament into which it is typically assembled, and an extended, unwound conformation. Modeling and corroborative mutational data indicate that proline isomerization is involved in the conversion between these helical and extended forms. Our findings affirm the strong structural similarities seen between class 5 fimbriae (from bacteria primarily causing gastrointestinal disease) and class 1 pili (from bacteria that cause urinary, respiratory, and other infections) in the absence of significant primary sequence similarity. They also suggest that morphological and biochemical differences between fimbrial types, regardless of class, provide structural specialization that facilitates survival of each bacterial pathotype in its preferred host microenvironment. Last, we present structural evidence for bacterial use of antigenic variation to evade host immune responses, in that residues occupying the predicted surface-exposed face of CfaB and related class 5 pilins show much higher genetic sequence variability than the remainder of the pilin protein.

PubMed: 19515814
DOI: 10.1073/pnas.0812843106

Experimental method

X-RAY DIFFRACTION (2.35 Å)