Catabolite repression of dra-nupC-pdp operon expression in Bacillus subtilis

Expression of the Bacillus subtilis dra-nupC-pdp operon is subject to catab olite repression by glucose. It was shown that a cis-acting catabolite-resp onsive element (CRE) sequence located 64 bp downstream of the transcription -start site mediated catabolite repression of the dra-nupC-pdp operon as it does for many other B. subtilis genes. Point mutations in the CRE sequence caused the loss of catabolite repression of the operon. Catabolite repress ion of dra-nupC-pdp expression was relieved in a ccpA mutant and was found to be dependent on both HPr and the HPr-like protein Crh. Furthermore, a tr anscriotipn-repair coupling factor, Mfd, was also found to be involved in t he glucose repression of dra-nupC-pdp expression. By the use of in vitro ge l mobility shift analysis, a specific HPr-P dependent binding of CcpA to th e dra CRE site was demonstrated.