Genomic organization, gene expression and activity profile of <i>Marinobacter hydrocarbonoclasticus</i> denitrification enzymes

Abstract

<i>M. hydrocarbonoclasticus</i> cells can reduce nitric and nitrous oxide <i>in vivo,</i> indicating that the four denitrification steps are active. Gene expression profile together with promoter regions analysis indicates the involvement of a cascade regulatory mechanism triggered by FNR-type in response to low oxygen tension, with nitric oxide and nitrate as secondary effectors, through DNR and NarXL, respectively. This global characterization of the denitrification pathway of a strict marine bacterium, contributes to the understanding of the N-cycle and nitrous oxide release in marine environments.