High-resolution cryo-EM using a common LaB₆ 120-keV electron microscope equipped with a sub-200-keV direct electron detector.

ABSTRACT: High-resolution cryo-electron microscopy (cryo-EM) requires costly 200- to 300-keV cryo-transmission electron microscopes (cryo-TEMs) with field emission gun (FEG) sources, stable columns, constant-powered lenses, autoloader, and direct electron detectors (DED). Recent advances in 100-keV imaging with the emergence of sub-200-keV optimized DED technology promises the development of more affordable cryo-TEMs. So far, 100-keV imaging has required microscopes with FEG sources. We here explored whether a standard 120-keV TEMs with thermionic lanthanum hexaboride (LaB₆) source can be upgraded with a sub-200-keV DED for high-resolution cryo-EM. Using this imaging configuration, we successfully obtained a 2.65 Å reconstruction for apoferritin, 4.33 Å for 64-kDa hemoglobin, and 4.4 Å fo

SUBMITTER: Venugopal H 

PROVIDER: S-EPMC11698077 | biostudies-literature | 2025 Jan

REPOSITORIES: biostudies-literature