Structural and thermodynamic characterization of pre- and postpolymerization states in the F4 fimbrial subunit FaeG.

TitleStructural and thermodynamic characterization of pre- and postpolymerization states in the F4 fimbrial subunit FaeG.
Publication TypeJournal Article
Year of Publication2009
AuthorsVan Molle, I., K. Moonens, A. Garcia-Pino, L. Buts, M. De Kerpel, L. Wyns, J. Bouckaert, and H. De Greve
JournalJ Mol Biol
Volume394
Issue5
Pagination957-67
Date Published2009 Dec 18
Type of Articlesmm
ISSN1089-8638
KeywordsAdhesins, Escherichia coli, Enterotoxigenic Escherichia coli, Kinetics, Models, Molecular, Protein Multimerization, Protein Structure, Quaternary, Protein Structure, Tertiary, Protein Subunits, Thermodynamics
Abstract

Enterotoxigenic Escherichia coli expressing F4 fimbriae are the major cause of porcine colibacillosis and are responsible for significant death and morbidity in neonatal and postweaned piglets. Via the chaperone-usher pathway, F4 fimbriae are assembled into thin, flexible polymers mainly composed of the single-domain adhesin FaeG. The F4 fimbrial system has been labeled eccentric because the F4 pilins show some features distinct from the features of pilins of other chaperone-usher-assembled structures. In particular, FaeG is much larger than other pilins (27 versus approximately 17 kDa), grafting an additional carbohydrate binding domain on the common immunoglobulin-like core. Structural data of FaeG during different stages of the F4 fimbrial biogenesis process, combined with differential scanning calorimetry measurements, confirm the general principles of the donor strand complementation/exchange mechanisms taking place during pilus biogenesis via the chaperone-usher pathway.

DOI10.1016/j.jmb.2009.09.059
Alternate JournalJ. Mol. Biol.
PubMed ID19799915