微生物的胞外电子传递界面

The interface of microbial extracellular electron transfer

微生物胞外电子传递(Extracellular electron transfer,EET)在地球生物化学循环、生态修复、废水处理以及资源再生等领域发挥着重要作用.自然界中胞外电子传递的界面性质各异,导致反应速率和效率明显不同.本文介绍了胞外电子传递过程涉及的无机物-微生物界面和有机物-微生物界面,总结了反应物表面性质与微生物的互作规律:反应物表面的氧化还原活性决定其电子接受/释放能力,从根本上影响胞外电子传递发生的可能性;微生物与反应物之间的氧化还原电势差决定了电子传递方向;表面电荷、润湿性、表面粗糙度、孔隙度和生物相容性综合影响微生物在固体表面的吸附、粘附、生物膜生长及活性,从而影响胞外电子传递的效率;导电性影响电子传输速率.本综述旨在通过对比各种反应界面,认识不同反应物界面间的共性与特性.这些认识有助于系统理解微生物胞外电子传递与环境的关系,为其在工程中的应用提供理论指导.

Microbial extracellular electron transfer(EET) plays an important role in the fields of earth biochemical cycle,ecological restoration,wastewater treatment and resource regeneration. In nature, the interface properties of extracellular electron transfer are different, resulting in significantly different reaction rates and efficiencies. In this article, we introduce the microbeinorganic substance interface and the microbe-organic substance interface involved in the process of extracellular electron transfer,and summarize the interaction rules between surface properties and microorganisms. The redox activities of reactants determine its electron accepting and releasing abilities, and fundamentally affects the possibility of extracellular electron transfer. The redox potential difference between the microorganism and reactants determines the direction of electron transfer. The surface charge,wettability,surface roughness,porosity and biocompatibility of the solid surface comprehensively affect the adsorption, adhesion, biofilm growth and activity of microorganisms on the solid-phase surface,thereby affecting the efficiency of extracellular electron transfer. The conductivity of the solid interface affects the electron transfer rate. This review aims to understand the commonalities and characteristics of different reaction interfaces by comparing various reaction interfaces. These understandings help to systematically understand the relationship between the EET behavior of microorganisms and environment,provide theoretical guidance for its application in engineering.