4NCD

Crystal Structure of Class 5 Fimbriae Chaperone CfaA

Summary for 4NCD

• Entry DOI: 10.2210/pdb4ncd/pdb
• Descriptor: Gram-negative pili assembly chaperone, N-terminal domain protein (2 entities in total)
• Functional Keywords: immunoglobulin fold, chaperone
• Biological source: Escherichia coli
• Total number of polymer chains: 1
• Total formula weight: 28329.70

Authors

Bao, R.,Xia, D. (deposition date: 2013-10-24, release date: 2014-08-27, Last modification date: 2024-10-16)

Primary citation

Bao, R.,Fordyce, A.,Chen, Y.X.,McVeigh, A.,Savarino, S.J.,Xia, D.
Structure of CfaA Suggests a New Family of Chaperones Essential for Assembly of Class 5 Fimbriae.
Plos Pathog., 10:e1004316-e1004316, 2014

PubMed Abstract: Adhesive pili on the surface of pathogenic bacteria comprise polymerized pilin subunits and are essential for initiation of infections. Pili assembled by the chaperone-usher pathway (CUP) require periplasmic chaperones that assist subunit folding, maintain their stability, and escort them to the site of bioassembly. Until now, CUP chaperones have been classified into two families, FGS and FGL, based on the short and long length of the subunit-interacting loops between its F1 and G1 β-strands, respectively. CfaA is the chaperone for assembly of colonization factor antigen I (CFA/I) pili of enterotoxigenic E. coli (ETEC), a cause of diarrhea in travelers and young children. Here, the crystal structure of CfaA along with sequence analyses reveals some unique structural and functional features, leading us to propose a separate family for CfaA and closely related chaperones. Phenotypic changes resulting from mutations in regions unique to this chaperone family provide insight into their function, consistent with involvement of these regions in interactions with cognate subunits and usher proteins during pilus assembly.

PubMed: 25122114
DOI: 10.1371/journal.ppat.1004316

Experimental method

X-RAY DIFFRACTION (2.037 Å)