Department of Chemical and Biological Physics , Weizmann Institute of Science , Rehovot 76100 , Israel.
Department of Physics and Astronomy , University of Southern California , Los Angeles , California 90089 , United States.
J Am Chem Soc. 2019 Dec 11;141(49):19198-19202. doi: 10.1021/jacs.9b09262. Epub 2019 Nov 11.
Multiheme cytochromes, located on the bacterial cell surface, function as long-distance (>10 nm) electron conduits linking intracellular reactions to external surfaces. This extracellular electron transfer process, which allows microorganisms to gain energy by respiring solid redox-active minerals, also facilitates the wiring of cells to electrodes. While recent studies have suggested that a chiral induced spin selectivity effect is linked to efficient electron transmission through biomolecules, this phenomenon has not been investigated in extracellular electron conduits. Using magnetic conductive probe atomic force microscopy, Hall voltage measurements, and spin-dependent electrochemistry of the decaheme cytochromes MtrF and OmcA from the metal-reducing bacterium MR-1, we show that electron transport through these extracellular conduits is spin-selective. Our study has implications for understanding how spin-dependent interactions and magnetic fields may control electron transport across biotic-abiotic interfaces in both natural and biotechnological systems.
多血红素细胞色素位于细菌细胞表面，作为长距离 (>10nm) 电子导体，将细胞内反应与外部表面连接起来。这种细胞外电子转移过程使微生物能够通过呼吸固体氧化还原活性矿物来获取能量，同时也促进了细胞与电极的连接。尽管最近的研究表明，手性诱导的自旋选择性效应对生物分子的有效电子传输有关联，但这种现象尚未在细胞外电子导体中进行研究。使用磁导探针原子力显微镜、霍尔电压测量和来自金属还原菌 MR-1 的 decaheme 细胞色素 MtrF 和 OmcA 的自旋相关电化学，我们表明，这些细胞外导体中的电子传输是自旋选择性的。我们的研究对于理解自旋相关相互作用和磁场如何可能控制自然和生物技术系统中生物-非生物界面的电子传输具有重要意义。
