Industrial methanol production converts methane from natural gas into methanol through a multistep chemical process. Biological methane-to-methanol conversion under moderate conditions and using biogas would be more environmentally friendly. Methanotrophs, bacteria that use methane as an energy source, convert methane into methanol in a single step catalyzed by the enzyme methane monooxygenase, but inhibition of methanol dehydrogenase, which catalyzes the subsequent conversion of methanol into formaldehyde, is a major challenge. In this study, we used the thermoacidophilic methanotroph “Methylacidiphilum fumariolicum” SolV for biological methanol production. This bacterium possesses a XoxF-type methanol dehydrogenase that is dependent on rare earth elements for activity. By using a cultivation medium nearly devoid of lanthanides, we reduced methanol dehydrogenase activity and obtained a continuous methanol-producing microbial culture. The methanol production rate and conversion efficiency were growth-rate dependent. A maximal conversion efficiency of 63% mol methanol produced per mol methane consumed was obtained at a relatively high growth rate, with a methanol production rate of 0.88 mmol/g (dry weight)/h. This study demonstrates that methanotrophs can be used for continuous methanol production. Full-scale application will require additional increases in the titer, production rate, and efficiency, which can be achieved by further decreasing the lanthanide concentration through the use of increased biomass concentrations and novel reactor designs to supply sufficient gases, including methane, oxygen, and hydrogen.

中文翻译：

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在不同的生长条件下，通过“ Methylacidiphilum fumariolicum” SolV生产甲醇。

工业甲醇生产通过多步化学过程将天然气中的甲烷转化为甲醇。在适度的条件下使用沼气进行生物甲烷到甲醇的转化将更加环保。甲烷营养菌是利用甲烷作为能源的细菌，在甲烷单加氧酶的催化下，一步将甲烷转化为甲醇，但是抑制甲醇脱氢酶却催化了甲醇随后转化为甲醛，这是一个重大挑战。在这项研究中，我们使用了嗜热嗜甲烷甲烷营养菌“甲基嗜酸性烟曲霉”用于生物甲醇生产的SolV。该细菌具有XoxF型甲醇脱氢酶，其活性取决于稀土元素。通过使用几乎没有镧系元素的培养基，我们降低了甲醇脱氢酶的活性并获得了连续的产甲醇微生物培养物。甲醇生产率和转化效率取决于生长速率。在相对较高的生长速率下，每消耗一摩尔甲烷可获得最大转化效率为63％的甲醇甲醇，甲醇的生产率为0.88 mmol / g（干重）/ h。这项研究表明，甲醇可以用于连续甲醇生产。全面应用将需要进一步提高效价，生产率和效率，