FIG 6.

Effect of the resD and nsrR mutations on nasD transcription. The wild-type (wt) and mutant strains carrying nasD-lacZ were anaerobically grown in 2× YT supplemented with 1% glucose and 0.2% nitrate (A) (nitrate respiration) or 0.5% glucose and 0.5% pyruvate (B) (fermentation). Cells were harvested at hourly intervals, and β-galactosidase activities (β-gal. act.) at T−1 (white bars) and T1 (black bars) are shown. Error bars are standard deviations for triplicates. Numbers in parentheses on the y axes show values for the resD and nsrR resD mutants.