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Gold nanoparticles and tilt pairs to assess protein flexibility by cryo-electron microscopy.

ABSTRACT: A computational method was developed to recover the three-dimensional coordinates of gold nanoparticles specifically attached to a protein complex from tilt-pair images collected by electron microscopy. The program was tested on a simulated dataset and applied to a real dataset comprising tilt-pair images recorded by cryo electron microscopy of RNA polymerase II in a complex with four gold-labeled single-chain antibody fragments. The positions of the gold nanoparticles were determined, and comparison of the coordinates among the tetrameric particles revealed the range of motion within the protein complexes.

SUBMITTER: Jagota M

PROVIDER: S-EPMC8238918 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature

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Gold nanoparticles and tilt pairs to assess protein flexibility by cryo-electron microscopy.

Jagota Milind M Townshend Raphael J L RJL Kang Lin-Woo LW Bushnell David A DA Dror Ron O RO Kornberg Roger D RD Azubel Maia M

Ultramicroscopy 20210504

A computational method was developed to recover the three-dimensional coordinates of gold nanoparticles specifically attached to a protein complex from tilt-pair images collected by electron microscopy. The program was tested on a simulated dataset and applied to a real dataset comprising tilt-pair images recorded by cryo electron microscopy of RNA polymerase II in a complex with four gold-labeled single-chain antibody fragments. The positions of the gold nanoparticles were determined, and compa ...[more]

PMID: 34062386

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