ISSN:
1572-9699
Keywords:
denitrification
;
pH
;
nitrite reductase
;
Paracoccus denitrificans
;
mRNA
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract The influence of pH on the denitrification activity of a continuous culture of Paracoccus denitrificans was studied in relation to the presence of nitrite. After a transition from aerobic to anaerobic conditions at the suboptimal pH of 6.8, P. denitrificans was not able to build up a functional denitrification pathway. Nitrite accumulated in the medium as the predominant denitrification product. Although the nitrite reductase gene was induced properly, the enzyme could not be detected at sufficient amounts in the culture. These observations indicate that either translation was somehow inhibited, or once synthesized nitrite reductase was inactivated, possibly by the high concentrations of nitrous acid (HNO2. Interestingly, when a P. denitrificans culture which was grown to steady-state under anaerobic conditions was then exposed to suboptimal pHs, cells exhibited a reduced overall denitrification activity, but neither nitrite nor any other denitrification intermediate accumulated.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1000342125891
Permalink
