Expression of nirK and nirS genes in two strains of Pseudomonas stutzeri harbouring both types of NO-forming nitrite reductases

Publication date: Available online 9 May 2018Source: Research in MicrobiologyAuthor(s): Lea Wittorf, Christopher M. Jones, Germán Bonilla-Rosso, Sara HallinAbstractReduction 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.

Source: Research in Microbiology - July 10, 2018 Category: Microbiology Source Type: research