Download MendeleyThe 2.0 A structure of human hypoxanthine-guanine phosphoribosyltransferase in complex with a transition-state analog inhibitor.
Shi, W., Li, C.M., Tyler, P.C., Furneaux, R.H., Grubmeyer, C., Schramm, V.L., Almo, S.C.(1999) Nat Struct Biol 6: 588-593
- PubMed: 10360366
- DOI: https://doi.org/10.1038/9376
- Primary Citation of Related Structures:
1BZY - PubMed Abstract:
The structure of human HGPRT bound to the transition-state analog immucillinGP and Mg2+-pyrophosphate has been determined to 2.0 A resolution. ImmucillinGP was designed as a stable analog with the stereoelectronic features of the transition state. Bound inhibitor at the catalytic site indicates that the oxocarbenium ion of the transition state is stabilized by neighboring-group participation from MgPPi and O5'. A short hydrogen bond forms between Asp 137 and the purine ring analog. Two Mg2+ ions sandwich the pyrophosphate and contact both hydroxyls of the ribosyl analog. The transition-state analog is shielded from bulk solvent by a catalytic loop that moves approximately 25 A to cover the active site and becomes an ordered antiparallel beta-sheet.
Organizational Affiliation:
Department of Biochemistry, Albert Einstein College of Medicine, Bronx, New York 10461, USA.
