Baumann B, van der Meer J R, Snozzi M, Zehnder A J
Swiss Federal Institute for Environmental Science and Technology (EAWAG), Dübendorf, Switzerland.
Antonie Van Leeuwenhoek. 1997 Oct;72(3):183-9. doi: 10.1023/a:1000342125891.
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 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.
研究了pH对反硝化副球菌连续培养物反硝化活性的影响，并与亚硝酸盐的存在相关联。在次优pH值6.8下从好氧条件转变为厌氧条件后，反硝化副球菌无法建立起功能性的反硝化途径。亚硝酸盐作为主要的反硝化产物在培养基中积累。尽管亚硝酸还原酶基因被正确诱导，但在培养物中无法检测到足够量的该酶。这些观察结果在某种程度上受到了抑制，或者一旦合成的亚硝酸还原酶被灭活，可能是由于高浓度的亚硝酸（HNO2）。有趣的是，当在厌氧条件下生长至稳态的反硝化副球菌培养物随后暴露于次优pH值时，细胞表现出整体反硝化活性降低，但亚硝酸盐和任何其他反硝化中间产物均未积累。
