1. Structural Biology and Molecular Biophysics
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2.8 Å resolution reconstruction of the Thermoplasma acidophilum 20 S proteasome using cryo-electron microscopy

  1. Melody G Campbell
  2. David Veesler
  3. Anchi Cheng
  4. Clinton S Potter
  5. Bridget Carragher  Is a corresponding author
  1. National Resource for Automated Molecular Microscopy, The Scripps Research Institute, United States
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Cite this article as: eLife 2015;4:e06380 doi: 10.7554/eLife.06380

Abstract

Recent developments in detector hardware and image-processing software have revolutionized single particle cryo-electron microscopy (cryoEM) and led to a wave of near-atomic resolution (typically ~3.3 Å) reconstructions. Reaching resolutions higher than 3 Å is a prerequisite for structure-based drug design and for cryoEM to become widely interesting to pharmaceutical industries. We report here the structure of the 700 kDa Thermoplasma acidophilum 20S proteasome (T20S), determined at 2.8 Å resolution by single-particle cryoEM. The quality of the reconstruction enables identifying the rotameric conformation adopted by some amino-acid side chains (rotamers) and resolving ordered water molecules, in agreement with the expectations for crystal structures at similar resolutions. The results described in this manuscript demonstrate that single particle cryoEM is capable of competing with X-ray crystallography for determination of protein structures of suitable quality for rational drug design.

Article and author information

Author details

  1. Melody G Campbell

    National Resource for Automated Molecular Microscopy, The Scripps Research Institute, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. David Veesler

    National Resource for Automated Molecular Microscopy, The Scripps Research Institute, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Anchi Cheng

    National Resource for Automated Molecular Microscopy, The Scripps Research Institute, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Clinton S Potter

    National Resource for Automated Molecular Microscopy, The Scripps Research Institute, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Bridget Carragher

    National Resource for Automated Molecular Microscopy, The Scripps Research Institute, La Jolla, United States
    For correspondence
    bcarr@nysbc.org
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Sjors HW Scheres, Medical Research Council Laboratory of Molecular Biology, United Kingdom

Publication history

  1. Received: January 8, 2015
  2. Accepted: February 27, 2015
  3. Accepted Manuscript published: March 11, 2015 (version 1)
  4. Version of Record published: March 23, 2015 (version 2)

Copyright

© 2015, Campbell et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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