Combined spectroelectrochemical and proteomic characterizations of bidirectional Alcaligenes faecalis-electrode electron transfer
Combined spectroelectrochemical and proteomic characterizations of bidirectional Alcaligenes faecalis-electrode electron transfer
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双向粪产碱菌电极电子转移的光谱电化学和蛋白质组学表征相结合
DOI：
10.1016/j.bios.2018.01.032
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发表时间：
2018
影响因子：
12.6
通讯作者：
Zhou Shungui
中科院分区：
文献类型：
--
作者：
Yu Linpeng;Yuan Yong;Rensing Christopher;Zhou Shungui
生物电化学系统使用微生物作为电流产生或消耗的催化剂。到目前为止，只有少数微生物被证明能够向外和向内进行胞外电子转移(EET)(即双向电子转移)。然而，微生物和胞外固体之间的电子交换机制仍然不确定。在这里，我们表明，粪产碱菌催化了向外的EET，并在+0.3V与SHE的平衡电位下发电，而它在−0.5V与SHE的平衡电位下进行了自养反硝化的EET。循环伏安和现场电化学FTIR光谱都表明，在向外和向内的EET过程中利用了不同的氧化还原成分。电子传递抑制实验首次表明，化合物I、II、III和质膜上的苯二酚池参与了双向EET。比较蛋白质组学表明，外向EET生物膜的蛋白质表达谱与内向EET生物膜的蛋白质表达谱有很大差异，提示菌毛蛋白和外膜蛋白可能分别负责界面外向和内向EET。这些结果提示了不同的电子传递途径。粪便生物膜可用于双向EET。
Bioelectrochemical systems use microbes as catalysts for current production or consumption. Up to now only a few microbes have been demonstrated to be capable of both outward and inward extracellular electron transfer (EET) (i.e. bidirectional electron transfer). However, the mechanisms of electron exchange between microbes and extracellular solids remain uncertain. Here, we showed thatAlcaligenes faecaliscatalyzed an outward EET and generated electricity at a poised potential of +0.3 V vs. SHE, whereas it conducted an inward EET for autotrophic denitrification at −0.5 V vs. SHE. Both cyclic voltammetry and in situ electrochemical FTIR spectroscopy revealed that different redox components were utilized during the outward and inward EET. Electron transport inhibitor experiments indicated for the first time that complex I, II, III, and the quinone pool on the plasma membrane were involved in the bidirectional EET. Comparative proteomics showed that the protein expression profile of outward-EET biofilms differed greatly from those of inward-EET biofilms, implying that the pili and outer membrane proteins might be responsible for the interfacial outward and inward EET, respectively. These results suggest different electron transport conduits ofA. faecalisbiofilms could be used for bidirectional EET.