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Annual Review of Microbiology

Volume 77, 2023

Electron Transfer Beyond the Outer Membrane: Putting Electrons to Rest

Abstract

Extracellular electron transfer (EET) is the physiological process that enables the reduction or oxidation of molecules and minerals beyond the surface of a microbial cell. The first bacteria characterized with this capability were and , both reported to couple their growth to the reduction of iron or manganese oxide minerals located extracellularly. A key difference between EET and nearly every other respiratory activity on Earth is the need to transfer electrons beyond the cell membrane. The past decade has resolved how well-conserved strategies conduct electrons from the inner membrane to the outer surface. However, recent data suggest a much wider and less well understood collection of mechanisms enabling electron transfer to distant acceptors. This review reflects the current state of knowledge from and , specifically focusing on transfer across the outer membrane and beyond—an activity that enables reduction of highly variable minerals, electrodes, and even other organisms.

Keyword(s): cytochrome, electron shuttles, extracellular electron transfer, Geobacter, Shewanella
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2023-09-15
2024-04-29
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/content/journals/10.1146/annurev-micro-032221-023725
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Electron Transfer Beyond the Outer Membrane: Putting Electrons to Rest
Annual Review of Microbiology 77, 517 (2023); https://doi.org/10.1146/annurev-micro-032221-023725
/content/journals/10.1146/annurev-micro-032221-023725
/content/journals/10.1146/annurev-micro-032221-023725
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