Microsecond Time-Resolved Cryo-EM Based on Jet Vitrification

Area of Science:

• Structural biology
• Biophysics
• Biochemistry

Background:

• Understanding protein function requires observing dynamics at fast timescales.
• Current cryo-electron microscopy (cryo-EM) methods offer microsecond resolution but limited observation windows.
• Observing protein dynamics is crucial for understanding their function.

Purpose of the Study:

• To develop a time-resolved cryo-electron microscopy (cryo-EM) technique with extended observation windows.
• To achieve microsecond time resolution for observing protein dynamics across multiple timescales.
• To capture fast protein dynamics crucial for biological function.

Main Methods:

• Utilizing laser flash to initiate protein dynamics.
• Employing jet vitrification for rapid sample freezing, arresting dynamics.
• Combining microsecond resolution with an observation window of up to seconds.
• Achieving near-atomic spatial resolution and 21 µs time resolution.

Main Results:

• Demonstrated microsecond to millisecond observation of protein dynamics.
• Successfully observed photoinduced dynamics of the light-driven sodium pump ErNaR.
• Extended the observable time window for cryo-EM studies of protein dynamics significantly.
• Achieved near-atomic spatial resolution and 21 µs temporal resolution.

Conclusions:

• The developed time-resolved cryo-EM technique significantly expands the capabilities of observing protein dynamics.
• This method enables the study of protein functions across microsecond to millisecond timescales.
• Future studies can leverage this technique to uncover intricate protein mechanisms.