FIG. 7.

Transcriptional analysis of trx genes. The parental strain (wild type [WT], B. fragilis strain 638R) and the isogenic trxD mutant (ΔtrxD, strain IB469) were exposed for 5 min to 500 μM, 100 μM, and 50 μM diamide or maintained under standard anaerobic conditions (0 μM control). For each condition, RNA was isolated and real-time RT-PCR was performed in triplicate. The sigma-54 modulation protein gene was used as a standard, and the results are expressed as fold induction relative to levels under the control condition. The values are means of fold induction, compared to the 0 μM control, from two independent experiments. The error bars indicate standard deviations.