Crystal structure of asparagine synthetase reveals a close evolutionary relationship to class II aminoacyl-tRNA synthetase.
Nakatsu, T., Kato, H., Oda, J.(1998) Nat Struct Biol 5: 15-19
- PubMed: 9437423 
- DOI: https://doi.org/10.1038/nsb0198-15
- Primary Citation of Related Structures:  
11AS, 12AS - PubMed Abstract: 
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.
Organizational Affiliation: 
Institute for Chemical Research, Kyoto University, Japan. oda@pclsp2.kuicr.kyoto-u.ac.jp