ArnR, a novel transcriptional regulator, represses expression of the narKGHJI operon in Corynebacterium glutamicum.

ABSTRACT: The narKGHJI operon that comprises putative nitrate/nitrite transporter (narK) and nitrate reductase (narGHJI) genes is required for the anaerobic growth of Corynebacterium glutamicum with nitrate as a terminal electron acceptor. In this study, we identified a gene, arnR, which encodes a transcriptional regulator that represses the expression of the narKGHJI operon in C. glutamicum cells under aerobic conditions. Disruption of arnR induced nitrate reductase activities of C. glutamicum cells and increased narKGHJI mRNA levels under aerobic growth conditions. DNA microarray analyses revealed that besides the narKGHJI operon, the hmp gene, which encodes flavohemoglobin, is negatively regulated by ArnR under aerobic conditions. Promoter-reporter assays indicated that arnR gene expression was p

SUBMITTER: Nishimura T 

PROVIDER: S-EPMC2347399 | biostudies-literature | 2008 May

REPOSITORIES: biostudies-literature