Friedrich Michael W
Max Planck Institute for Terrestrial Microbiology, Marburg, Germany.
Methods Enzymol. 2005;397:428-42. doi: 10.1016/S0076-6879(05)97026-2.
In many anoxic environments, methanogenesis is the predominant terminal electron accepting process involved in the mineralization of organic matter, which is catalyzed by methanogenic Archaea. These organisms represent a unique but phylogenetically diverse guild of prokaryotes, which can be conveniently tracked in the environment by targeting the mcrA gene as a functional marker. This gene encodes the alpha subunit of the methyl-coenzyme M reductase (MCR), which catalyzes the last step in methanogenesis and is present in all methanogens. Cultivation-independent analysis of methanogenic communities involves the polymerase chain reaction (PCR) amplification of the mcrA gene from extracted community DNA, comparative analysis of mcrA clone libraries, or PCR-based fingerprinting analysis by terminal restriction fragment polymorphism analysis (T-RFLP). It has also been suggested that anaerobic methane-oxidizing Archaea possess MCR, which facilitates detection of this novel group of "reverse methanogens" as well using the mcrA gene as a functional marker.
在许多缺氧环境中，产甲烷作用是参与有机物矿化的主要末端电子接受过程，该过程由产甲烷古菌催化。这些生物代表了一类独特但系统发育多样的原核生物群体，通过将mcrA基因作为功能标记，可以在环境中方便地追踪它们。该基因编码甲基辅酶M还原酶（MCR）的α亚基，它催化产甲烷作用的最后一步，并且存在于所有产甲烷菌中。对产甲烷群落的非培养分析包括从提取的群落DNA中进行mcrA基因的聚合酶链反应（PCR）扩增、mcrA克隆文库的比较分析，或通过末端限制性片段长度多态性分析（T-RFLP）进行基于PCR的指纹分析。也有人提出，厌氧甲烷氧化古菌拥有MCR，这也使得利用mcrA基因作为功能标记来检测这一新的“反向产甲烷菌”群体成为可能。
