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bioRxiv · 10.1101/2022.09.14.507962

Microsecond melting and revitrification of cryo samples with a correlative light-electron microscopy approach

Bongiovanni, G.·Harder, O. F.·Drabbels, M.·Lorenz, U. J.
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Abstract

We have recently introduced a novel approach to time-resolved cryo-electron microscopy (cryo-EM) that affords microsecond time resolution. It involves melting a cryo sample with a laser beam to allow dynamics of the embedded particles to occur. Once the laser beam is switched off, the sample revitrifies within just a few microseconds, trapping the particles in their transient configurations, which can subsequently be imaged to obtain a snap shot of the dynamics at this point in time. While we have previously performed such experiments with a modified transmission electron microscope, we here demonstrate a simpler implementation that uses an optical microscope. We believe that this will make our technique more easily accessible and hope that it will encourage other groups to apply microsecond time-resolved cryo-EM to study the fast dynamics of a variety of proteins.

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Bongiovanni, G., Harder, O. F., Drabbels, M., Lorenz, U. J.. 2022-09-14. Microsecond melting and revitrification of cryo samples with a correlative light-electron microscopy approach. https://doi.org/10.1101/2022.09.14.507962

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