Where Do 3D Protein Structure Data Come From?
  1. Accurate: 83% by X-ray crystallography, 15% by NMR.

  2. Rough: Comparative modeling, but templates available for only ~20% of domains.

  3. Ab initio theory does not predict tertiary structure accurately enough for most purposes.

  4. Details ...

by Eric Martz, University of Massachusetts, October 2004 for ProteinExplorer.Org