FIG 6.
The feuA gene is required for enterobactin to promote sporulation gene expression in B. subtilis. The fluorescence intensity of wild-type (WT) or siderophore-specific SBP mutant (feuA, fpiA, yfmC, yfiY, fhuD, or yxeB) B. subtilis PsspB-yfp microcolony lawns in response to 10 μM enterobactin was quantified; corresponding fluorescence images of the lawns (false-colored green) are shown at the top. There was a significant decrease in the promotion of sporulation gene expression on the feuA lawns, compared to wild-type B. subtilis (n = 3). Error bars represent standard deviations. *, P < 0.01.