Figure 2.

Uropathogenic E. coli import Ni–Ybt. a–c, UTI89ΔybtA expressing none, one, or both of the Ybt uptake components (pfyuA and pybtPQ) were grown in M63 minimal media and exposed to 0.2 μm exogenous Ni–Ybt for 2 h prior to isolation and extraction of Ni–Ybt and metal-free Ybt from the supernatant (a and c, respectively) or cells (b). Ybt or Ni–Ybt were quantified by LC-MS/MS. Cartoons indicate which Ybt species was assessed in which graph. Experiments were performed in triplicate; results are shown as mean ± S.D. **, p ≤ 0.01; ***, p ≤ 0.001; ****, p ≤ 0.0001 based on a t test (two-tailed); NS, nonsignificant.