Refined structure of the complex between guanylate kinase and its substrate GMP at 2.0 A resolution

J Mol Biol. 1992 Apr 20;224(4):1127-41. doi: 10.1016/0022-2836(92)90474-x.

Abstract

The crystal structure of guanylate kinase from Saccharomyces cerevisiae complexed with its substrate GMP has been refined at a resolution of 2.0 A. The final crystallographic R-factor is 17.3% in the resolution range 7.0 A to 2.0 A for all reflections of the 100% complete data set. The final model has standard geometry with root-mean-square deviations of 0.016 A in bond lengths and 3.0 in bond angles. It consists of all 186 amino acid residues, the N-terminal acetyl group, the substrate GMP, one sulfate ion and 174 water molecules. Guanylate kinase is structurally related to adenylate kinases and G-proteins with respect to its central beta-sheet with connecting helices and the giant anion hole that binds nucleoside triphosphates. These nucleotides are ATP and GTP for the kinases and GTP for the G-proteins. The chain segment binding the substrate GMP of guanylate kinase differs grossly from the respective part of the adenylate kinases; it has no counterpart in the G-proteins. The binding mode of GMP is described in detail. Probably, the observed structure represents one of several structurally quite different intermediate states of the catalytic cycle.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Triphosphate / metabolism
  • Adenylate Kinase / ultrastructure
  • Amino Acid Sequence
  • Binding Sites
  • Crystallography
  • GTP-Binding Proteins / ultrastructure
  • Guanosine Monophosphate* / metabolism
  • Guanylate Kinases
  • Models, Molecular
  • Molecular Sequence Data
  • Motion
  • Nucleoside-Phosphate Kinase / ultrastructure*
  • Protein Conformation
  • Saccharomyces cerevisiae / enzymology
  • Solvents
  • Sulfates / metabolism
  • Temperature
  • Water
  • X-Ray Diffraction

Substances

  • Solvents
  • Sulfates
  • Water
  • Guanosine Monophosphate
  • Adenosine Triphosphate
  • Adenylate Kinase
  • Nucleoside-Phosphate Kinase
  • Guanylate Kinases
  • GTP-Binding Proteins