D. Choudhury et al., X-ray structure of the FimC-FimH chaperone-adhesin complex from uropathogenic Escherichia coli, SCIENCE, 285(5430), 1999, pp. 1061-1066
Type 1 pili-adhesive fibers expressed in most members of the Enterobacteria
ceae family-mediate binding to mannose receptors on host cells through the
FimH adhesin. Pilus biogenesis proceeds by way of the chaperone/usher pathw
ay. The x-ray structure of the FimC-FimH chaperone-adhesin complex from uro
pathogenic Escherichia coli at 2.5 angstrom resolution reveals the basis fo
r carbohydrate recognition and for pilus assembly. The carboxyl-terminal pi
lin domain of FimH has an immunoglobulin-like fold, except that the seventh
strand is missing, leaving part of the hydrophobic core exposed. A donor s
trand complementation mechanism in which the chaperone donates a strand to
complete the pilin domain explains the basis for both chaperone function an
d pilus biogenesis.