Methanol is generally metabolized through a pathway initiated by a cobalamine-containing methanol methyltransferase by anaerobic methylotrophs (such as methanogens and acetogens), or through oxidation to formaldehyde using a methanol dehydrogenase by aerobes. Methanol is an important substrate in deep-subsurface environments, where thermophilic sulfate-reducing bacteria of the genus Desulfotomaculum have key roles. Here, we study the methanol metabolism of Desulfotomaculum kuznetsovii strain 17^T, isolated from a 3000-m deep geothermal water reservoir. We use proteomics to analyze cells grown with methanol and sulfate in the presence and absence of cobalt and vitamin B12. The results indicate the presence of two methanol-degrading pathways in D. kuznetsovii, a cobalt-dependent methanol methyltransferase and a cobalt-independent methanol dehydrogenase, which is further confirmed by stable isotope fractionation. This is the first report of a microorganism utilizing two distinct methanol conversion pathways. We hypothesize that this gives D. kuznetsovii a competitive advantage in its natural environment.

中文翻译：

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深层地下硫酸盐还原剂Desulfotomaculum kuznetsovii采用两种甲醇降解途径。

甲醇通常通过厌氧甲基营养菌（如产甲烷菌和产乙酸菌）由含钴胺的甲醇甲基转移酶引发的途径代谢，或通过需氧甲醇脱氢酶氧化为甲醛。在深地下环境中，甲醇是Desulfotomaculum属的嗜热硫酸盐还原细菌具有关键作用的重要底物。在这里，我们研究Desulfotomaculum kuznetsovii菌株17 ^T的甲醇代谢隔离于3000米深的地热水库中。我们使用蛋白质组学来分析在存在和不存在钴和维生素B12的情况下用甲醇和硫酸盐生长的细胞。结果表明，在库氏假单胞菌中存在两个甲醇降解途径，即钴依赖性甲醇甲基转移酶和钴非依赖性甲醇脱氢酶，这可通过稳定的同位素分级进一步证实。这是微生物利用两种不同的甲醇转化途径的首次报道。我们假设这使库氏假单胞菌在其自然环境中具有竞争优势。