The periplasmic nitrate reductase in Pseudomonas sp. strain G-179 catalyzes the first step of denitrification.

ABSTRACT: Both membrane-bound and periplasmic nitrate reductases have been found in denitrifying bacteria. Yet the role of periplasmic nitrate reductase in denitrification has not been clearly defined. To analyze the function of the periplasmic nitrate reductase in Pseudomonas sp. strain G-179, the nap gene cluster was identified and found to be linked to genes involved in reduction of nitrite and nitric oxide and anaerobic heme biosynthesis. Mutation in the nap region rendered the cells incapable of growing under anaerobic conditions with nitrate as the alternative electron acceptor. No nitrate reduction activity was detected in the Nap- mutant, but that activity could be restored by complementation with the nap region. Unlike the membrane-bound nitrate reductase, the nitrate reduction activity in

SUBMITTER: Bedzyk L 

PROVIDER: S-EPMC93722 | biostudies-literature | 1999 May

REPOSITORIES: biostudies-literature