Triclinic lysozyme at 0.65 A resolution

Acta Crystallogr D Biol Crystallogr. 2007 Dec;63(Pt 12):1254-68. doi: 10.1107/S0907444907054224. Epub 2007 Nov 16.


The crystal structure of triclinic hen egg-white lysozyme (HEWL) has been refined against diffraction data extending to 0.65 A resolution measured at 100 K using synchrotron radiation. Refinement with anisotropic displacement parameters and with the removal of stereochemical restraints for the well ordered parts of the structure converged with a conventional R factor of 8.39% and an R(free) of 9.52%. The use of full-matrix refinement provided an estimate of the variances in the derived parameters. In addition to the 129-residue protein, a total of 170 water molecules, nine nitrate ions, one acetate ion and three ethylene glycol molecules were located in the electron-density map. Eight sections of the main chain and many side chains were modeled with alternate conformations. The occupancies of the water sites were refined and this step is meaningful when assessed by use of the free R factor. A detailed description and comparison of the structure are made with reference to the previously reported triclinic HEWL structures refined at 0.925 A (at the low temperature of 120 K) and at 0.95 A resolution (at room temperature).

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, N.I.H., Intramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Anisotropy
  • Catalytic Domain
  • Chick Embryo
  • Crystallization
  • Crystallography, X-Ray
  • Least-Squares Analysis
  • Models, Molecular
  • Muramidase / chemistry*
  • Protein Conformation
  • Torsion, Mechanical


  • hen egg lysozyme
  • Muramidase