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Fast slow folding of an outer membrane porin.

ABSTRACT: In comparison to globular proteins, the spontaneous folding and insertion of β-barrel membrane proteins are surprisingly slow, typically occurring on the order of minutes. Using single-molecule Förster resonance energy transfer to report on the folding of fluorescently labeled outer membrane protein G we measured the real-time insertion of a β-barrel membrane protein from an unfolded state. Folding events were rare and fast (<20 ms), occurring immediately upon arrival at the membrane. This combination of infrequent, but rapid, folding resolves this apparent dichotomy between slow ensemble kinetics and the typical timescales of biomolecular folding.

SUBMITTER: Weatherill EE

PROVIDER: S-EPMC9171805 | biostudies-literature | 2022 May

REPOSITORIES: biostudies-literature

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Fast slow folding of an outer membrane porin.

Weatherill Eve E EE Fahie Monifa A MA Marshall David P DP Andvig Rachel A RA Cheetham Matthew R MR Chen Min M Wallace Mark I MI

Proceedings of the National Academy of Sciences of the United States of America 20220512 20

In comparison to globular proteins, the spontaneous folding and insertion of β-barrel membrane proteins are surprisingly slow, typically occurring on the order of minutes. Using single-molecule Förster resonance energy transfer to report on the folding of fluorescently labeled outer membrane protein G we measured the real-time insertion of a β-barrel membrane protein from an unfolded state. Folding events were rare and fast (<20 ms), occurring immediately upon arrival at the membrane. This combi ...[more]

PMID: 35549548

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