title: Crystallization and preliminary crystallographic characterization of catechol-O-methyltransferase in complex with its cosubstrate and an inhibitor.
abstract: Catechol-O-methyltransferase (COMT) is involved in the metabolism of catecholamines, catechol steroids and xenobiotic catechols. A precise knowledge of the enzyme-inhibitor structural interactions could help in the design of better inhibitors. Soluble rat COMT was expressed in Escherichia coli and the recombinant protein was crystallized with a new tight-binding inhibitor, BIA 3-335 [1-(3,4-dihydroxy-5-nitrophenyl)-3-(n-3'-trifluoromethylphenyl)piperazine-1-propanone dihydrochloride]. The crystals were obtained by the sitting-drop vapour-diffusion method using PEG 6K as a precipitant. These crystals diffracted to better than 1.9 A and belong to the trigonal space group P3(2)21. The unit-cell parameters for the crystal measured at room temperature were a = b = 51.5, c = 168.3 A; each shrank by about 1 A on freezing.
authors.affiliation: Instituto de Biologia Experimental e Tecnológica (IBET), Apt. 12, 2748-901 Oeiras, Portugal.
authors.forename: M L
authors.initials: ML
authors.lastname: Rodrigues
authors.forename: M
authors.initials: M
authors.lastname: Archer
authors.forename: M J
authors.initials: MJ
authors.lastname: Bonifácio
authors.forename: P
authors.initials: P
authors.lastname: Soares-da-Silva
authors.forename: M A
authors.initials: MA
authors.lastname: Carrondo
mesh_terms: D000818:Animals; D002394:Catechol O-Methyltransferase / Q000737:chemistry* / Q000235:genetics; D003460:Crystallization; D018360:Crystallography, X-Ray; D004791:Enzyme Inhibitors / Q000737:chemistry; D011487:Protein Conformation; D051381:Rats; D011994:Recombinant Proteins / Q000737:chemistry; D013379:Substrate Specificity
chemical_list: D004791:Enzyme Inhibitors; D011994:Recombinant Proteins; D002394:Catechol O-Methyltransferase