Overview of electroactive microorganisms and electron transfer mechanisms in microbial electrochemistry

• Published in: Bioresource technology Vol. 347; p. 126579
• Main Authors: Thapa, Bhim Sen, Kim, Taeyoung, Pandit, Soumya, Song, Young Eun, Afsharian, Yasamin Pesaran, Rahimnejad, Mostafa, Kim, Jung Rae, Oh, Sang-Eun
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.03.2022
• Subjects: Bioelectric Energy Sources; Bioelectrochemical system; electricity; Electroactive microorganisms; Electrochemistry; Electrodes; Electron transfer; Electron Transport; Electrons; electrosynthesis; eukaryotic cells; microalgae; Microbial electrosynthesis; Microbial metabolism; prokaryotic cells; redox potential; Electron transfer; Microbial electrosynthesis; Electroactive microorganisms; Bioelectrochemical system; Microbial metabolism
• ISSN: 0960-8524; 1873-2976; 1873-2976
• DOI: 10.1016/j.biortech.2021.126579

•This article focuses on electroactive microorganisms in bioelectrochemical systems.•Comprehensive discussion on electroactive microbes and electron transfer phenomenon.•Emphasis on metabolic activity in electrogenic and electrotrophic microorganisms.•Brief note on synthetic biology approach in microbial electrochemistry.•Comprehensive discussion on bioanode and biocathode reactions in BES. Electroactive microorganisms acting as microbial electrocatalysts have intrinsic metabolisms that mediate a redox potential difference between solid electrodes and microbes, leading to spontaneous electron transfer to the electrode (exo-electron transfer) or electron uptake from the electrode (endo-electron transfer). These microbes biochemically convert various organic and/or inorganic compounds to electricity and/or biochemicals in bioelectrochemical systems (BESs) such as microbial fuel cells (MFCs) and microbial electrosynthesis cells (MECs). For the past two decades, intense studies have converged to clarify electron transfer mechanisms of electroactive microbes in BESs, which thereby have led to improved bioelectrochemical performance. Also, many novel exoelectrogenic eukaryotes as well as prokaryotes with electroactive properties are being continuously discovered. This review presents an overview of electroactive microorganisms (bacteria, microalgae and fungi) and their exo- and endo-electron transfer mechanisms in BESs for optimizing and advancing bioelectrochemical techniques.