Single-particle cryo-EM at atomic resolution.

Area of Science:

• Structural Biology
• Biophysics
• Biochemistry

Background:

• Protein structure dictates biological function.
• High-resolution protein structures are crucial for understanding molecular mechanisms.
• Electron cryo-microscopy (cryo-EM) has advanced protein structure determination.

Purpose of the Study:

• To achieve atomic resolution using cryo-EM single-particle analysis.
• To visualize individual atoms, solvent molecules, and hydrogen bonds in proteins.
• To enable structure-based drug discovery and high-throughput screening.

Main Methods:

• Utilized a novel electron source, energy filter, and camera for cryo-EM.
• Applied single-particle analysis to a human membrane protein (β3 GABA receptor) and mouse apoferritin.
• Developed advanced techniques for data acquisition and sample preparation.

Main Results:

• Obtained a 1.7 Å resolution cryo-EM reconstruction of the β3 GABA receptor.
• Achieved 1.22 Å resolution for mouse apoferritin, providing an atomic-resolution view.
• Visualized hydrogen atoms and their bonding networks in protein structures.

Conclusions:

• Technological advancements in cryo-EM enable routine atomic resolution.
• This resolution level facilitates detailed understanding of protein structure and function.
• The method supports small molecule screening and structure-based drug discovery.