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Cryo-EM reveals the structural basis of long-range electron transport in a cytochrome-based bacterial nanowire.

ABSTRACT: Electrically conductive pili from Geobacter species, termed bacterial nanowires, are intensely studied for their biological significance and potential in the development of new materials. Using cryo-electron microscopy, we have characterized nanowires from conductive G. sulfurreducens pili preparations that are composed solely of head-to-tail stacked monomers of the six-heme C-type cytochrome OmcS. The unique fold of OmcS - closely wrapped around a continuous stack of hemes that can serve as an uninterrupted path for electron transport - generates a scaffold that supports the unbranched chain of hemes along the central axis of the filament. We present here, at 3.4?Å resolution, the structure of this cytochrome-based filament and discuss its possible role in long-range biological electron transport.

SUBMITTER: Filman DJ

PROVIDER: S-EPMC6584659 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Cryo-EM reveals the structural basis of long-range electron transport in a cytochrome-based bacterial nanowire.

Filman David J DJ Marino Stephen F SF Ward Joy E JE Yang Lu L Mester Zoltán Z Bullitt Esther E Lovley Derek R DR Strauss Mike M

Communications biology 20190619

Electrically conductive pili from <i>Geobacter</i> species, termed bacterial nanowires, are intensely studied for their biological significance and potential in the development of new materials. Using cryo-electron microscopy, we have characterized nanowires from conductive <i>G. sulfurreducens</i> pili preparations that are composed solely of head-to-tail stacked monomers of the six-heme C-type cytochrome OmcS. The unique fold of OmcS - closely wrapped around a continuous stack of hemes that ca ...[more]

PMID: 31240257

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Cryo-EM reveals the structural basis of long-range electron transport in a cytochrome-based bacterial nanowire

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