Preliminary X-ray analysis of a new crystal form of recombinant pig kidneyDOPA decarboxylase

DOPA decarboxylase is responsible for the synthesis of the key neurotransmi tters dopamine and serotonin via decarboxylation of L-3,4-dihydroxyphenylal anine (L-DOPA) and L-5-hydroxytryptophan, respectively. The crystals of rec ombinant DOPA decarboxylase differ from those previously reported for the e nzyme purified from pig kidney. They belong to space group P622 with unit-c ell dimensions a = b = 302.6, c = 178.1 Angstrom. Both the self-rotation fu nction and the good diffraction quality of these crystals (2.5 Angstrom on a synchrotron source) suggest that there should be at least three protein d imers in the asymmetric unit. Diffraction data sets have been collected for the native enzyme and a heavy-atom derivative.