6K73

Chaperone-tip adhesin complex is vital for synergistic activation of CFA/I fimbriae biogenesis

Summary for 6K73

• Entry DOI: 10.2210/pdb6k73/pdb
• Descriptor: Colonization factor antigen I chaperone CfaA, CFA/I fimbrial subunit E, GLYCEROL, ... (5 entities in total)
• Functional Keywords: enterotoxigenic escherichia coli, chaperone-usher fimbriae, periplasmic chaperone, adhesive subunit, binding motif, chaperone
• Biological source: Escherichia coli; More
• Total number of polymer chains: 4
• Total formula weight: 126880.35

Authors

Bao, R.,He, L.H. (deposition date: 2019-06-05, release date: 2020-06-10, Last modification date: 2024-10-16)

Primary citation

He, L.H.,Wang, H.,Liu, Y.,Kang, M.,Li, T.,Li, C.C.,Tong, A.P.,Zhu, Y.B.,Song, Y.J.,Savarino, S.J.,Prouty, M.G.,Xia, D.,Bao, R.
Chaperone-tip adhesin complex is vital for synergistic activation of CFA/I fimbriae biogenesis.
Plos Pathog., 16:e1008848-e1008848, 2020

PubMed Abstract: Colonization factor CFA/I defines the major adhesive fimbriae of enterotoxigenic Escherichia coli and mediates bacterial attachment to host intestinal epithelial cells. The CFA/I fimbria consists of a tip-localized minor adhesive subunit, CfaE, and thousands of copies of the major subunit CfaB polymerized into an ordered helical rod. Biosynthesis of CFA/I fimbriae requires the assistance of the periplasmic chaperone CfaA and outer membrane usher CfaC. Although the CfaE subunit is proposed to initiate the assembly of CFA/I fimbriae, how it performs this function remains elusive. Here, we report the establishment of an in vitro assay for CFA/I fimbria assembly and show that stabilized CfaA-CfaB and CfaA-CfaE binary complexes together with CfaC are sufficient to drive fimbria formation. The presence of both CfaA-CfaE and CfaC accelerates fimbria formation, while the absence of either component leads to linearized CfaB polymers in vitro. We further report the crystal structure of the stabilized CfaA-CfaE complex, revealing features unique for biogenesis of Class 5 fimbriae.

PubMed: 33007034
DOI: 10.1371/journal.ppat.1008848

Experimental method

X-RAY DIFFRACTION (2.7742 Å)