Bacterial adhesion to target cells enhanced by shear force.
Surface adhesion of bacteria generally occurs in the presence of shear stress, and the lifetime of receptor bonds is expected to be shortened in the presence of external force. However, by using Escherichia coli expressing the lectin-like adhesin FimH and guinea pig erythrocytes in flow chamber experiments, we show that bacterial attachment to target cells switches from loose to firm upon a 10-fold increase in shear stress applied. Steered molecular dynamics simulations of tertiary structure of the FimH receptor binding domain and subsequent site-directed mutagenesis studies indicate that shear-enhancement of the FimH-receptor interactions involves extension of the interdomain linker chain under mechanical force. The ability of FimH to function as a force sensor provides a molecular mechanism for discrimination between surface-exposed and soluble receptor molecules.
Department of Bioengineering, 98195, Seattle, WA, USA
Wendy E
WE
Thomas
Elena
E
Trintchina
Manu
M
Forero
Viola
V
Vogel
Evgeni V
EV
Sokurenko
D018829:Adhesins, Bacterial / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D018830:Adhesins, Escherichia coli; D000818:Animals; D001422:Bacterial Adhesion; D001696:Biomechanical Phenomena; D002449:Cell Aggregation; D003198:Computer Simulation; D004912:Erythrocytes / Q000166:cytology / Q000382:microbiology*; D004926:Escherichia coli / Q000235:genetics / Q000502:physiology*; D036781:Fimbriae Proteins; D006168:Guinea Pigs; D008958:Models, Molecular; D009154:Mutation; D017434:Protein Structure, Tertiary; D013329:Structure-Activity Relationship
D018829:Adhesins, Bacterial; D018830:Adhesins, Escherichia coli; C058769:fimH protein, E coli; D036781:Fimbriae Proteins