Abstract
Inhibitors of the enzyme catechol-O-methyltransferase (COMT) are used as co-adjuvants in the therapy of Parkinson's disease. A recombinant form of the soluble cytosolic COMT from rat has been co-crystallized with a new potent inhibitor, BIA 8-176 [(3,4-dihydroxy-2-nitrophenyl)phenylmethanone], by the vapour-diffusion method using PEG 6K as precipitant. Crystals diffract to 1.6 A resolution on a synchrotron-radiation source and belong to the monoclinic space group P2(1), with unit-cell parameters a = 52.77, b = 79.63, c = 61.54 A, beta = 91.14 degrees.