Coma-corrected rapid single-particle cryo-EM data collection on the CRYO ARM 300

Area of Science:

• Structural Biology
• Biophysics
• Microscopy

Background:

• Single-particle cryogenic electron microscopy (cryo-EM) is crucial for determining protein structures.
• Increased demand for high-resolution electron microscopes necessitates higher data collection throughput.
• Current methods require stage movement, limiting imaging speed.

Purpose of the Study:

• To characterize the optical properties of the JEOL CRYO ARM 300 under off-axis illumination.
• To evaluate the feasibility of high-throughput data collection using beam-image shifts and coma correction.
• To demonstrate rapid, automated acquisition of high-resolution cryo-EM data.

Main Methods:

• Characterization of JEOL CRYO ARM 300 optical properties with a K3 camera under off-axis illumination.
• Implementation of large beam-image shifts (up to 10 µm) combined with off-axis coma correction.
• Data collection on apoferritin using a rapid acquisition protocol.

Main Results:

• Efficient coma correction was achieved for beam-image shifts of at least 10 µm.
• Routine data collection throughput of 6000–9000 images per day was enabled.
• Apoferritin reconstruction achieved a resolution of 1.7 Å using the rapid data-collection procedure.

Conclusions:

• The JEOL CRYO ARM 300 facilitates high-throughput cryo-EM data collection through optimized optical performance.
• Large beam-image shifts and off-axis coma correction significantly increase imaging rates without compromising resolution.
• This technology enables rapid, automated acquisition of high-resolution cryo-EM micrographs for structural biology research.