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Achieving better-than-3-A resolution by single-particle cryo-EM at 200 keV.

ABSTRACT: Nearly all single-particle cryo-EM structures resolved to better than 4-Å resolution have been determined using 300-keV transmission electron microscopes (TEMs). We demonstrate that it is possible to obtain reconstructions of macromolecular complexes of different sizes to better than 3-Å resolution using a 200-keV TEM. These structures are of sufficient quality to unambiguously assign amino acid rotameric conformations and identify ordered water molecules.

SUBMITTER: Herzik MA

PROVIDER: S-EPMC5679434 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

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Achieving better-than-3-Å resolution by single-particle cryo-EM at 200 keV.

Herzik Mark A MA Wu Mengyu M Lander Gabriel C GC

Nature methods 20171009 11

Nearly all single-particle cryo-EM structures resolved to better than 4-Å resolution have been determined using 300-keV transmission electron microscopes (TEMs). We demonstrate that it is possible to obtain reconstructions of macromolecular complexes of different sizes to better than 3-Å resolution using a 200-keV TEM. These structures are of sufficient quality to unambiguously assign amino acid rotameric conformations and identify ordered water molecules. ...[more]

PMID: 28991891

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