Cryo-EM in Focus: Transforming the Landscape of Membrane Protein Research

Determining the structure of membrane proteins (MPs) is crucial for understanding many biological processes at the molecular level. However, this has historically been challenging due to difficulties associated with MPs purification and stabilization, and the fact that interactions with detergents may adversely affect the protein structure and activity. In an in-depth study of the Haemophilus influenzae Tellurite-Resistance Protein A (HiTehA) purified with different detergents and structurally characterized using cryo-EM, we show how the sample maintains structural integrity across the various detergents, providing insights into the relationship between MPs and solubilizing agents. In addition, we show that cryo-EM structure determination of small, fully embedded MPs that lack clear fiducial markers is possible even when using a standard 200 keV microscope and routine data collection and processing workflows.