Multiheme Cytochrome Mediated Redox Conduction through Shewanella oneidensis MR-1 Cells

作者：Xu Shuai; Barrozo Alexandre; Tender Leonard M; Krylov Anna I; El Naggar Mohamed Y^*

来源：Journal of the American Chemical Society, 2018, 140(32): 10085-10089.

DOI：10.1021/jacs.8b05104

Multiheme cytochromes function as extracellular electron transfer (EET) conduits that extend the metabolic reach of microorganisms to external solid surfaces. These conduits are also proposed to facilitate long-distance electron transport along cellular membranes and across multiple cells. Here we report electrochemical gating measurements of Shewanella oneidensis MR-1 cells linking interdigitated electrodes. The dependence of the source-drain current on gate potential demonstrates a redox conduction mechanism, which we link to the presence of multiheme cytochromes of the Mtr pathway. We also find that the measured thermal activation energy of 0.29 +/- 0.03 eV is consistent with these obtained from electron hopping calculations through the S. oneidensis Mtr outer-membrane decaheme cytochromes. Our measurements and calculations have implications for understanding and controlling micrometer-scale electron transport in microbial systems.

• 出版日期2018-8-15