title: Characterization and crystallization of human uroporphyrinogen decarboxylase.
abstract: The cytosolic enzyme uroporphyrinogen decarboxylase (URO-D) catalyzes the fifth step in the heme biosynthetic pathway, converting uroporphyrinogen to coproporphyrinogen by decarboxylating the four acetate side chains of the substrate. Recombinant human URO-D has been expressed in Escherichia coli with a histidine tag and has been purified to homogeneity. Purified protein was determined to be a monodisperse dimer by dynamic light scattering. Equilibrium sedimentation analysis confirmed that the protein is dimeric, with a dissociation constant of 0.1 microM. URO-D containing an amino-terminal histidine tag was crystallized in space group P3(1)21 or its enantiomer P3(2)21 with unit cell dimensions a = b = 103.6 A, c = 75.2 A. There is one molecule in the asymmetric unit, consistent with generation of the dimer by the twofold axis of this crystallographic operator. Native data have been collected to 3.0 a resolution.
authors.affiliation: Department of Medicine, University of Utah, School of Medicine, Salt Lake City 84132, USA. john.phllips@hsc.utah.edu
authors.forename: J D
authors.initials: JD
authors.lastname: Phillips
authors.forename: F G
authors.initials: FG
authors.lastname: Whitby
authors.forename: J P
authors.initials: JP
authors.lastname: Kushner
authors.forename: C P
authors.initials: CP
authors.lastname: Hill
mesh_terms: D002500:Centrifugation, Isopycnic; D003461:Crystallography; D019281:Dimerization; D006801:Humans; D008027:Light; D011994:Recombinant Proteins / Q000737:chemistry; D012542:Scattering, Radiation; D014575:Uroporphyrinogen Decarboxylase / Q000737:chemistry* / Q000235:genetics
chemical_list: D011994:Recombinant Proteins; D014575:Uroporphyrinogen Decarboxylase