Download MendeleyStructure of ACC synthase inactivated by the mechanism-based inhibitor L-vinylglycine.
Capitani, G., Tschopp, M., Eliot, A.C., Kirsch, J.F., Grutter, M.G.(2005) FEBS Lett 579: 2458-2462
- PubMed: 15848188
- DOI: https://doi.org/10.1016/j.febslet.2005.03.048
- Primary Citation of Related Structures:
1YNU - PubMed Abstract:
L-Vinylglycine (L-VG) is both a substrate for and a mechanism-based inhibitor of 1-aminocyclopropane-1-carboxylate (ACC) synthase. The ratio of the rate constants for catalytic conversion to alpha-ketobutyrate and ammonia to inactivation is 500/1. The crystal structure of the covalent adduct of the inactivated enzyme was determined at 2.25 Angstroms resolution. The active site contains an external aldimine of the adduct of L-VG with the pyridoxal 5'-phosphate cofactor. The side chain gamma-carbon of L-VG is covalently bound to the epsilon-amino group of Lys273. This species corresponds to one of the two alternatives proposed by Feng and Kirsch [Feng, L. and Kirsch, J.F. (2000) L-Vinylglycine is an alternative substrate as well as a mechanism-based inhibitor of 1-aminocyclopropane-1-carboxylate synthase. Biochemistry 39, 2436-2444] and presumably results from Michael addition to a vinylglycine ketimine intermediate.
Organizational Affiliation:
Biochemisches Institut der Universität Zürich, Switzerland. capitani@bioc.unizh.ch
