RpoE-dependent transcriptomes of Haemophilus ducreyi

To potentially understand how H. ducreyi responds to membrane stress, here we defined RpoE-dependent genes using RNA-Seq. We identified 180 RpoE-dependent genes, of which 98% were upregulated; a major set of these genes encodes homologues of envelope maintenance and repair factors. We also identified and validated a putative RpoE promoter consensus sequence, which was enriched in the majority of RpoE-dependent targets. Comparison of RpoE-dependent genes to those controlled by CpxR showed that each transcription factor regulated a distinct set of genes. Given that RpoE activated a large number of genes encoding envelope maintenance and repair factors and CpxRA represses genes encoding envelope-localized proteins, these data suggest that RpoE and CpxRA appear to play distinct yet complementary roles in regulating envelope homeostasis in H. ducreyi. Overall design: RNA of Haemophilus ducreyi 35000HP wild-type strain containing a rpoE inducible plasmid and wild-type strain containing a control plasmid were collected at 0 minutes, 5 minutes, and 10 minutes after induction in quadruplicate.