CO2 conversion to methane and biomass in obligate methylotrophic methanogens in marine sediments.,The ISME Journal

当前位置： X-MOL 学术 › ISME J. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

CO2 conversion to methane and biomass in obligate methylotrophic methanogens in marine sediments.
The ISME Journal ( IF 10.8 ) Pub Date : 2019-04-30 , DOI: 10.1038/s41396-019-0425-9
Xiuran Yin _{1,

2,

3} , Weichao Wu _{2,

4,

5} , Mara Maeke _{1,

3} , Tim Richter-Heitmann ₁ , Ajinkya C Kulkarni _{1,

2,

3} , Oluwatobi E Oni _{1,

2} , Jenny Wendt _{2,

4} , Marcus Elvert _{2,

4} , Michael W Friedrich _{1,

2}

Affiliation

Methyl substrates are important compounds for methanogenesis in marine sediments but diversity and carbon utilization by methylotrophic methanogenic archaea have not been clarified. Here, we demonstrate that RNA-stable isotope probing (SIP) requires 13C-labeled bicarbonate as co-substrate for identification of methylotrophic methanogens in sediment samples of the Helgoland mud area, North Sea. Using lipid-SIP, we found that methylotrophic methanogens incorporate 60-86% of dissolved inorganic carbon (DIC) into lipids, and thus considerably more than what can be predicted from known metabolic pathways (~40% contribution). In slurry experiments amended with the marine methylotroph Methanococcoides methylutens, up to 12% of methane was produced from CO2, indicating that CO2-dependent methanogenesis is an alternative methanogenic pathway and suggesting that obligate methylotrophic methanogens grow in fact mixotrophically on methyl compounds and DIC. Although methane formation from methanol is the primary pathway of methanogenesis, the observed high DIC incorporation into lipids is likely linked to CO2-dependent methanogenesis, which was triggered when methane production rates were low. Since methylotrophic methanogenesis rates are much lower in marine sediments than under optimal conditions in pure culture, CO2 conversion to methane is an important but previously overlooked methanogenic process in sediments for methylotrophic methanogens.

中文翻译：

海洋沉积物中的专性甲基营养产甲烷菌将二氧化碳转化为甲烷和生物质。

甲基底物是海洋沉积物中产甲烷的重要化合物，但甲基营养产甲烷古菌的多样性和碳利用尚未阐明。在这里，我们证明了 RNA 稳定同位素探测 (SIP) 需要 13C 标记的碳酸氢盐作为共同底物，以识别北海 Helgoland 泥区沉积物样品中的甲基营养产甲烷菌。使用脂质-SIP，我们发现甲基营养产甲烷菌将 60-86% 的溶解无机碳 (DIC) 结合到脂质中，因此比已知代谢途径预测的要多得多（约 40% 的贡献）。在用海洋甲基营养菌 Methanococcoidesmethylutens 修正的泥浆实验中，高达 12% 的甲烷是由二氧化碳产生的，表明依赖 CO2 的产甲烷作用是一种替代的产甲烷途径，并表明专性甲基营养产甲烷菌实际上在甲基化合物和 DIC 上混合营养生长。虽然甲醇形成甲烷是产甲烷的主要途径，但观察到的高 DIC 掺入脂质可能与 CO2 依赖性产甲烷有关，这是在甲烷产量低时触发的。由于海洋沉积物中的甲基营养产甲烷率远低于纯培养的最佳条件下，因此二氧化碳转化为甲烷是沉积物中甲基营养产甲烷菌的重要但以前被忽视的产甲烷过程。虽然甲醇形成甲烷是产甲烷的主要途径，但观察到的高 DIC 掺入脂质可能与 CO2 依赖性产甲烷有关，这是在甲烷产量低时触发的。由于海洋沉积物中的甲基营养产甲烷率远低于纯培养的最佳条件下，因此二氧化碳转化为甲烷是沉积物中甲基营养产甲烷菌的重要但以前被忽视的产甲烷过程。虽然甲醇形成甲烷是产甲烷的主要途径，但观察到的高 DIC 掺入脂质可能与 CO2 依赖性产甲烷有关，这是在甲烷产量低时触发的。由于海洋沉积物中的甲基营养产甲烷率远低于纯培养的最佳条件下，因此二氧化碳转化为甲烷是沉积物中甲基营养产甲烷菌的重要但以前被忽视的产甲烷过程。

更新日期：2019-05-16

点击分享查看原文

点击收藏

公开下载

阅读更多本刊新发论文