Electron cryomicroscopy of single particles at subnanometer resolution

Curr Opin Struct Biol. 2005 Oct;15(5):571-7. doi: 10.1016/j.sbi.2005.08.004.


Electron cryomicroscopy and single-particle reconstruction have advanced substantially over the past two decades. There are now numerous examples of structures that have been solved using this technique to better than 10 A resolution. At such resolutions, direct identification of alpha helices is possible and, often, beta-sheet-containing regions can be identified. The most numerous subnanometer resolution structures are the icosahedral viruses, as higher resolution is easier to achieve with higher symmetry. Important non-icosahedral structures solved to subnanometer resolution include several ribosome structures, clathrin assemblies and, most recently, the Ca2+ release channel. There is now hope that, in the next few years, this technique will achieve resolutions approaching 4 A, permitting a complete trace of the protein backbone without reference to a crystal structure.

Publication types

  • Review

MeSH terms

  • Animals
  • Chaperonin 60 / chemistry
  • Chaperonin 60 / ultrastructure
  • Clathrin / chemistry
  • Clathrin / ultrastructure
  • Cryoelectron Microscopy / methods*
  • Humans
  • Models, Molecular
  • Nanostructures / chemistry*
  • Nanostructures / ultrastructure
  • Ribosomes / chemistry
  • Ribosomes / ultrastructure
  • Ryanodine Receptor Calcium Release Channel / chemistry
  • Viral Proteins / chemistry
  • Viruses / chemistry
  • Viruses / ultrastructure


  • Chaperonin 60
  • Clathrin
  • Ryanodine Receptor Calcium Release Channel
  • Viral Proteins