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Protein identification from electron cryomicroscopy maps by automated model building and side-chain matching.

ABSTRACT: Using single-particle electron cryo-microscopy (cryo-EM), it is possible to obtain multiple reconstructions showing the 3D structures of proteins imaged as a mixture. Here, it is shown that automatic map interpretation based on such reconstructions can be used to create atomic models of proteins as well as to match the proteins to the correct sequences and thereby to identify them. This procedure was tested using two proteins previously identified from a mixture at resolutions of 3.2 Å, as well as using 91 deposited maps with resolutions between 2 and 4.5 Å. The approach is found to be highly effective for maps obtained at resolutions of 3.5 Å and better, and to have some utility at resolutions as low as 4 Å.

SUBMITTER: Terwilliger TC

PROVIDER: S-EPMC8025881 | biostudies-literature | 2021 Apr

REPOSITORIES: biostudies-literature

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Protein identification from electron cryomicroscopy maps by automated model building and side-chain matching.

Terwilliger Thomas C TC Sobolev Oleg V OV Afonine Pavel V PV Adams Paul D PD Ho Chi Min CM Li Xiaorun X Zhou Z Hong ZH

Acta crystallographica. Section D, Structural biology 20210330 Pt 4

Using single-particle electron cryo-microscopy (cryo-EM), it is possible to obtain multiple reconstructions showing the 3D structures of proteins imaged as a mixture. Here, it is shown that automatic map interpretation based on such reconstructions can be used to create atomic models of proteins as well as to match the proteins to the correct sequences and thereby to identify them. This procedure was tested using two proteins previously identified from a mixture at resolutions of 3.2 Å, as well ...[more]

PMID: 33825706

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