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Structure and Stoichiometry of the Ton Molecular Motor.

ABSTRACT: The Ton complex is a molecular motor that uses the proton gradient at the inner membrane of Gram-negative bacteria to generate force and movement, which are transmitted to transporters at the outer membrane, allowing the entry of nutrients into the periplasmic space. Despite decades of investigation and the recent flurry of structures being reported by X-ray crystallography and cryoEM, the mode of action of the Ton molecular motor has remained elusive, and the precise stoichiometry of its subunits is still a matter of debate. This review summarizes the latest findings on the Ton system by presenting the recently reported structures and related reports on the stoichiometry of the fully assembled complex.

SUBMITTER: Celia H

PROVIDER: S-EPMC7014051 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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Structure and Stoichiometry of the Ton Molecular Motor.

Celia Herve H Noinaj Nicholas N Buchanan Susan K SK

International journal of molecular sciences 20200107 2

The Ton complex is a molecular motor that uses the proton gradient at the inner membrane of Gram-negative bacteria to generate force and movement, which are transmitted to transporters at the outer membrane, allowing the entry of nutrients into the periplasmic space. Despite decades of investigation and the recent flurry of structures being reported by X-ray crystallography and cryoEM, the mode of action of the Ton molecular motor has remained elusive, and the precise stoichiometry of its subuni ...[more]

PMID: 31936081

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Author Correction: Cryo-EM structure of the bacterial Ton motor subcomplex ExbB-ExbD provides information on structure and stoichiometry.

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