Lan Jian-Ying, Jiang Hai-Ming, Li Xia
School of Life Science and Technology, Inner Mongolia University of Science and Technology, Baotou 014010, Inner Mongolia, China.
Inner Mongolia Key Laboratory of Biomass-Energy Conversion, Baotou 014010, Inner Mongolia, China.
Ying Yong Sheng Tai Xue Bao. 2021 Jan;32(1):358-368. doi: 10.13287/j.1001-9332.202101.032.
Hydrogen and formic acid have been considered as the intermediate electron transporters among microbes for a long time. In recent years, however, it has been found that direct interspecies electron transfer (DIET) might be an alternative beyond hydrogen/formic acid to transfer electron among microbes. As a new way of electron transfer among microbes, the electron transfer efficiency of DIET is higher than that of traditional hydrogen/formate transfer. The discovery of DIET has changed the traditional understanding that the growth and metabolism of microbial syntrophism must rely on electron carriers such as hydrogen or formic acid, and also has opened a new perspective for the study of microbial interaction. Although great progress has been made in the study of DIET, in-depth studies are still lacking on the microbes that can form co-culture via DIET, the mechanism of DIET, and the factors affecting DIET. In this review, we summarized the microbes that can form DIET, the mechanism underlying the extracellular electron transfer of microbe acted as electron donor in DIET, as well as the mechanism underlying the extracellular electron transfer of microbe acted as electron acceptor in DIET. The effects of conductive materials on DIET were elaborated, and several research directions for DIET were proposed, with the aim to mitigate performance degradation and facilitate research and development in this area.
长期以来，氢气和甲酸一直被认为是微生物之间的中间电子传递体。然而，近年来发现，直接种间电子转移（DIET）可能是一种替代氢气/甲酸在微生物间转移电子的方式。作为微生物间电子转移的一种新方式，DIET的电子转移效率高于传统的氢气/甲酸转移。DIET的发现改变了传统观念，即微生物互营生长和代谢必须依赖氢气或甲酸等电子载体，也为微生物相互作用的研究开辟了新视角。尽管在DIET研究方面取得了很大进展，但对于能够通过DIET形成共培养的微生物、DIET的机制以及影响DIET的因素仍缺乏深入研究。在这篇综述中，我们总结了能够形成DIET的微生物、DIET中作为电子供体的微生物细胞外电子转移机制以及DIET中作为电子受体的微生物细胞外电子转移机制。阐述了导电材料对DIET的影响，并提出了DIET的几个研究方向，旨在减轻性能退化并促进该领域的研发。
