Heterotrophic bacteria actively participate in the biogeochemical cycle of sulfur on Earth. The heterotrophic bacterium Cupriavidus pinatubonensis JMP134 contains several enzymes involved in sulfur oxidation, but how these enzymes work together to oxidize sulfide in the bacterium has not been studied. Using gene-deletion and whole-cell assays, we determined that the bacterium uses sulfide:quinone oxidoreductase to oxidize sulfide to polysulfide, which is further oxidized to sulfite by persulfide dioxygenase. Sulfite spontaneously reacts with polysulfide to produce thiosulfate. The sulfur-oxidizing (Sox) system oxidizes thiosulfate to sulfate. Flavocytochrome c sulfide dehydrogenase enhances thiosulfate oxidation by the Sox system but couples with the Sox system for sulfide oxidation to sulfate in the absence of sulfide:quinone oxidoreductase. Thus, C. pinatubonensis JMP134 contains a main pathway and a contingent pathway for sulfide oxidation.

中文翻译：

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异养细菌pinatubonensis Cupriavidus pinatubonensis JMP134用硫代硫酸盐作为关键中间体将硫化物氧化为硫酸盐。

异养细菌积极参与地球上硫的生物地球化学循环。异养细菌Pinnatubonensis Cupriavidus pinatubonensis JMP134包含几种参与硫氧化的酶，但是尚未研究这些酶如何协同作用以氧化细菌中的硫化物。通过基因删除和全细胞分析，我们确定该细菌使用硫化物：醌氧化还原酶将硫化物氧化为多硫化物，再通过过硫化物双加氧酶将其氧化为亚硫酸盐。亚硫酸盐与多硫化物自发反应，生成硫代硫酸盐。硫氧化（Sox）系统将硫代硫酸盐氧化为硫酸盐。黄细胞色素c硫化物脱氢酶通过Sox系统增强了硫代硫酸盐的氧化作用，但在没有硫化物：醌氧化还原酶的情况下，与Sox系统结合将硫化物氧化为硫酸盐。因此，C。pinatubonensis JMP134包含硫化物氧化的主要途径和或有途径。