Abstract

Reduction of nitrite to nitric oxide in denitrification is catalysed by two different nitrite reductases, encoded by nirS or nirK. Long considered mutually exclusive and functionally redundant in denitrifying bacteria, we show expression of both genes co-occurring in Pseudomonas stutzeri. The differential expression patterns between strain AN10 and JM300 in relation to oxygen and nitrate and their different denitrification phenotypes, with AN10 reducing nitrate more rapidly and accumulating nitrite, suggest that nirS and nirK can have different roles. Dissimilar gene arrangements and transcription factors in the nir gene neighbourhoods could explain the observed differences in gene expression and denitrification activity. (C) 2018 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

Keywords

AN10; Denitrification; Gene arrangement; JM300; Phenotype

Published in

Research in Microbiology
2018, volume: 169, number: 6, pages: 343-347
Publisher: ELSEVIER SCIENCE BV

Authors' information