Crystal structure of asparagine synthetase reveals a close evolutionary relationship to class II aminoacyl-tRNA synthetase

Nat Struct Biol. 1998 Jan;5(1):15-9. doi: 10.1038/nsb0198-15.


The crystal structure of E. coli asparagine synthetase has been determined by X-ray diffraction analysis at 2.5 A resolution. The overall structure of the enzyme is remarkably similar to that of the catalytic domain of yeast aspartyl-tRNA synthetase despite low sequence similarity. These enzymes have a common reaction mechanism that implies the formation of an aminoacyl-adenylate intermediate. The active site architecture and most of the catalytic residues are also conserved in both enzymes. These proteins have probably evolved from a common ancestor even though their sequence similarities are small. The functional and structural similarities of both enzymes suggest that new enzymatic activities would generally follow the recruitment of a protein catalyzing a similar chemical reaction.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Amino Acyl-tRNA Synthetases / ultrastructure*
  • Aspartate-Ammonia Ligase / ultrastructure*
  • Aspartic Acid / chemistry
  • Binding Sites
  • Crystallography, X-Ray
  • Escherichia coli / enzymology
  • Models, Molecular
  • Molecular Sequence Data
  • Protein Binding
  • Protein Structure, Secondary
  • Protein Structure, Tertiary
  • Saccharomyces cerevisiae / enzymology
  • Sequence Alignment
  • Sequence Homology, Amino Acid


  • Aspartic Acid
  • Amino Acyl-tRNA Synthetases
  • Aspartate-Ammonia Ligase

Associated data

  • PDB/11AS
  • PDB/12AS