FIG 6.

BosR regulates Cu homeostasis in B. burgdorferi. The Mn, Fe, Cu, and Zn levels in three isogenic B31 strains differing only in bosR, including the wild-type parental strain (WT), the bosR mutant (bosR), and the complemented bosR mutant (Comp.) were determined by ICP-SFMS. Spirochetes were cultivated microaerobically at 25°C or 37°C to early stationary phase in the BSK-H medium (Sigma-Aldrich). Data represent means (plus SEM) of the results from two independent samples. P values are derived from a two-way ANOVA, followed by Bonferroni posttest. For clarity, only P values for strain-dependent differences are indicated: **, P < 0.01; ***, P < 0.001; those for temperature-dependent differences are discussed only in the text.