Visualizing the conformational dynamics of proteins by time-resolved electron microscopy
The function of many proteins involves large-amplitude domain motions that occur on a timescale of microseconds to millisecond. In the absence of tools to directly observe these dynamics, our understanding of the function of proteins is necessarily incomplete and must frequently rely on extrapolation from known static structures. Here, the implementation of real-time imaging of single particle dynamics in liquid phase is proposed with both microsecond time resolution as well as near-atomic spatial resolution. The experimental approach builds on several recent technological advances, namely the advent of Time-Resolved (“Four-dimensional”) Electron Microscopy, graphene liquid cell technology, and direct electron detection cameras, which are combined with established single-particle reconstruction techniques in cryo-Electron Microscopy. Visualizing the conformational dynamics of proteins will fundamentally advance our understanding of these nanoscale machines and has the potential to greatly benefit biomedical applications.