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bioRxiv · 10.1101/2023.04.19.536710

Fast viral dynamics revealed by Microsecond Time-Resolved Cryo-EM

Harder, O. F.·Barrass, S. V.·Drabbels, M.·Lorenz, U. J.
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Abstract

Observing proteins as they perform their tasks has largely remained elusive, which has left our understanding of protein function fundamentally incomplete. To enable such observations, we have recently proposed a novel technique that improves the time resolution of cryo-electron microscopy (cryo EM) to microseconds. Here, we demonstrate that microsecond time-resolved cryo-EM enables observations of fast protein dynamics. We use our approach to elucidate the mechanics of the capsid of cowpea chlorotic mottle virus (CCMV), whose large-amplitude motions play a crucial role in the viral life cycle. We observe that a pH jump causes the extended configuration of the capsid to contract on the microsecond timescale. While this is a concerted process, the motions of the capsid proteins involve different timescales, leading to a curved reaction path.

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Harder, O. F., Barrass, S. V., Drabbels, M., Lorenz, U. J.. 2023-04-19. Fast viral dynamics revealed by Microsecond Time-Resolved Cryo-EM. https://doi.org/10.1101/2023.04.19.536710

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