Figure 2: Residue 223 variation in FimH of S. Typhimurium and Typhi swaps host specificity.
From: Allelic variation contributes to bacterial host specificity
(a) Host origin distribution for 580 S. Typhimurium isolates that have either a valine (Val) or an alanine (Ala) at position 223 of FimH. (b) Binding to three human (in red) and four bovine (in black) intestinal epithelial cells of recombinant E. coli expressing Salmonella type 1 fimbriae with the FimH1 or FimH7 alleles that have valine or alanine at position 223, respectively. (c) The different binding properties of fimH80 with valine and engineered fimH80 with alaline at position 223 for three human and four bovine enterocytes. The data in b and c are expressed as mean percentages of bacterial binding relative to the difference between fimH2 (100% binding for FimH of S. Typhimurium strain AJB3, not shown) and ΔfimH (0% binding) with±s.e.m. of three experiments. P-values were calculated by using a one-sided paired t-test: *P<0.05; **P<0.01; ***P<0.001.
