Fast slow folding of an Outer Membrane Porin

Weatherill, E. E.; Fahie, M. A.; Marshall, D. P.; Andvig, R. A.; Cheetham, M. R.; Chen, M.; Wallace, M.

doi:10.1101/2021.04.06.438691

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bioRxiv · 10.1101/2021.04.06.438691

Fast slow folding of an Outer Membrane Porin

Weatherill, E. E.·Fahie, M. A.·Marshall, D. P.·Andvig, R. A.·Cheetham, M. R.·Chen, M.·Wallace, M.

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Abstract

In comparison to globular proteins, the spontaneous folding and insertion of {beta}-barrel membrane proteins is surprisingly slow, typically occurring on the order of minutes. Using single-molecule Forster Resonance Energy Transfer to report on the folding of fluorescently-labelled Outer Membrane Protein G we measured the real-time insertion of a {beta}-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 rare, folding resolves this apparent dichotomy between slow ensemble kinetics, and the typical timescales of biomolecular folding.

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Weatherill, E. E., Fahie, M. A., Marshall, D. P., Andvig, R. A., Cheetham, M. R., Chen, M., Wallace, M.. 2021-04-06. Fast slow folding of an Outer Membrane Porin. https://doi.org/10.1101/2021.04.06.438691

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