Manipulating denitrifying sulfide removal of Pseudomonas sp. C27 with nitrite as sole nitrogen source: Shotgun proteomics analysis.

Pseudomonas sp. C27 can effectively conduct denitrifying sulfide removal (DSR) reactions via autotrophic denitrification, heterotrophic denitrification and coupled-cycle pathway. This study is the first to cultivate strain C27 using nitrite as the sole nitrogen source, and to conduct shotgun proteomics analysis and investigate the characteristics of DSR growth of strain C27 with nitrate or nitrite as sole nitrogen source. Shotgun proteomics analysis identified a total of 42 specially expressed proteins of C27 in the nitrite medium, based on which, together with chemical analysis data, a supplementary pathway of sulfur metabolism for C27 from sulfate to thiosulfate via intermediate adenosine-5'-phosphosulfate and 3'-phosphoadenosine-5'-phosphosulfate was proposed. Based on the newly revised scheme, the use of nitrite as sole nitrogen source expands the assessible regime of DSR reactions by C27 and provides the potential to recover renewable chemicals such as pyruvate and succinate from the coupled-cycle pathway.