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The structure of bacterial ParM filaments.

ABSTRACT: Bacterial ParM is a homolog of eukaryotic actin and is involved in moving plasmids so that they segregate properly during cell division. Using cryo-EM and three-dimensional reconstruction, we show that ParM filaments have a different structure from F-actin, with very different subunit-subunit interfaces. These interfaces result in the helical handedness of the ParM filament being opposite to that of F-actin. Like F-actin, ParM filaments have a variable twist, and we show that this involves domain-domain rotations within the ParM subunit. The present results yield new insights into polymorphisms within F-actin, as well as the evolution of polymer families.

SUBMITTER: Orlova A

PROVIDER: S-EPMC3541950 | biostudies-literature | 2007 Oct

REPOSITORIES: biostudies-literature

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The structure of bacterial ParM filaments.

Orlova Albina A Garner Ethan C EC Galkin Vitold E VE Heuser John J Mullins R Dyche RD Egelman Edward H EH

Nature structural & molecular biology 20070916 10

Bacterial ParM is a homolog of eukaryotic actin and is involved in moving plasmids so that they segregate properly during cell division. Using cryo-EM and three-dimensional reconstruction, we show that ParM filaments have a different structure from F-actin, with very different subunit-subunit interfaces. These interfaces result in the helical handedness of the ParM filament being opposite to that of F-actin. Like F-actin, ParM filaments have a variable twist, and we show that this involves domai ...[more]

PMID: 17873883

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2023-09-01 | GSE157512 | GEO

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