Kinetics and Crystal Structure of Catechol-O-Methyltransferase Complex with Co-Substrate and a Novel Inhibitor with Potential Therapeutic ApplicationBonifacio, M.J., Archer, M., Rodrigues, M.L., Matias, P.M., Learmonth, D.A., Carrondo, M.A., Soares-da-Silva, P.
(2002) Mol.Pharmacol. 62: 795
- PubMed: 12237326
- PubMed Abstract:
- Crystallization and Preliminary Crystallographic Characterization of Catechol-O-Methyltransferase in Complex with its Co-Substrate and an Inhibitor
Rodrigues, M.L.,Archer, M.,Bonifacio, M.J.,Soares-da-Silva, P.,Carrondo, M.A.
(2001) Acta Crystallogr.,Sect.D D57: 906
Catechol-O-methyltransferase (COMT; E.C. 22.214.171.124) is a ubiquitous enzyme in nature that plays an important role in the metabolism of catechol neurotransmitters and xenobiotics. In particular, inactivation of drugs such as L-3,4-dihydroxyphenylalanine ...
Catechol-O-methyltransferase (COMT; E.C. 126.96.36.199) is a ubiquitous enzyme in nature that plays an important role in the metabolism of catechol neurotransmitters and xenobiotics. In particular, inactivation of drugs such as L-3,4-dihydroxyphenylalanine (L-DOPA) via O-methylation is of relevant pharmacological importance, because L-DOPA is currently the most effective drug used in the treatment of Parkinson's disease. This justified the interest in developing COMT inhibitors as potential adjuncts to L-DOPA therapy. The kinetics of inhibition by BIA 3-335 (1-[3,4-dihydroxy-5-nitrophenyl]-3-(N-3'-trifluormethylphenyl)-piperazine-1-propanone dihydrochloride) were characterized using recombinant rat soluble COMT. BIA 3-335 was found to act as a potent, reversible, tight-binding inhibitor of COMT with a K(i) of 6.0 +/- 1.6 nM and displaying a competitive inhibition toward the substrate binding site and uncompetitive inhibition toward the S-adenosyl-L-methionine (SAM) binding site. The 2.0-A resolution crystal structure of COMT in complex with its cosubstrate SAM and a novel inhibitor BIA 3-335 shows the atomic interactions between the important residues at the active site and the inhibitor. This is the first report of a three-dimensional structure determination of COMT complexed with a potent, reversible, and tight-binding inhibitor that is expected to have therapeutic applications.
Department of Research and Development, BIAL, S. Mamede do Coronado, Portugal.