The alternative oxidase (AOX) gene in Vibrio fischeri is controlled by NsrR and upregulated in response to nitric oxide.

ABSTRACT: Alternative oxidase (AOX) is a respiratory oxidase found in certain eukaryotes and bacteria; however, its role in bacterial physiology is unclear. Exploiting the genetic tractability of the bacterium Vibrio fischeri, we explore the regulation of aox expression and AOX function. Using quantitative PCR and reporter assays, we demonstrate that aox expression is induced in the presence of nitric oxide (NO), and that the NO-responsive regulatory protein NsrR mediates the response. We have identified key amino acid residues important for NsrR function and experimentally confirmed a bioinformatically predicted NsrR binding site upstream of aox. Microrespirometry demonstrated that oxygen consumption by V. fischeri CydAB quinol oxidase is inhibited by NO treatment, whereas oxygen consumption by AOX

SUBMITTER: Dunn AK 

PROVIDER: S-EPMC3682826 | biostudies-literature | 2010 Jul

REPOSITORIES: biostudies-literature