Gao Kailin, Lu Yahai
College of Urban and Environmental Sciences, Peking University, Beijing, China.
Front Microbiol. 2021 Mar 22;12:611739. doi: 10.3389/fmicb.2021.611739. eCollection 2021.
It has been suggested that a few methanogens are capable of extracellular electron transfers. For instance, can directly capture electrons from the coexisting microbial cells of other species. and retrieve electrons from direct interspecies electron transfer (DIET). Recently, , designated strain YSL, has been found to grow DIET in the co-culture with . can perform anaerobic methane oxidation and respiratory growth relying on Fe(III) reduction through the extracellular electron transfer. is capable of electromethanogenesis under the conditions where electron-transfer mediators like H or formate are limited. The membrane-bound multiheme c-type cytochromes (MHC) and electrically-conductive cellular appendages have been assumed to mediate the extracellular electron transfer in bacteria like and species. These molecules or structures are rare but have been recently identified in a few methanogens. Here, we review the current state of knowledge for the putative extracellular electron transfers in methanogens and highlight the opportunities and challenges for future research.
有人提出，一些产甲烷菌能够进行细胞外电子转移。例如， 能够直接从其他物种共存的微生物细胞中捕获电子。 和 通过直接种间电子转移（DIET）从 中获取电子。最近，已发现 ，命名为菌株YSL，在与 的共培养中通过DIET生长。 能够通过细胞外电子转移进行厌氧甲烷氧化和依赖于Fe（III）还原的呼吸生长。在诸如H或甲酸盐等电子转移介质有限的条件下， 能够进行电产甲烷作用。膜结合的多血红素c型细胞色素（MHC）和导电细胞附属物被认为介导了诸如 和 物种等细菌中的细胞外电子转移。这些分子或结构很少见，但最近在一些产甲烷菌中已被鉴定出来。在这里，我们综述了产甲烷菌中假定的细胞外电子转移的当前知识状态，并强调了未来研究的机遇和挑战。
