title: Crystallization and preliminary X-ray studies of membrane-associated Escherichia coli dihydroorotate dehydrogenase.
abstract: Dihydroorotate dehydrogenases (DHODs) are flavin-containing enzymes which catalyse the conversion of (S)-dihydroorotate to orotate, the fourth step in the de novo biosynthesis of pyrimidine nucleotides. Two major families of DHODs have now been identified based on their amino-acid sequence similarities. The two families differ in their reaction mechanisms, but structures are only known of enzymes belonging to family 1. DHOD from Escherichia coli is a typical member of family 2, which contains the membrane-associated enzymes from Gram-negative bacteria and eukaryotes. Yellow crystals grown of this enzyme belong to the space group P4(1)2(1)2 or P4(3)2(1)2. The unit-cell parameters are a = b = 119.2, c = 294.3 A. Owing to the rather large c axis, the currently available resolution of data is 2.2 A.
authors.affiliation: Centre for Crystallographic Studies, Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen O, Denmark.
authors.forename: P
authors.initials: P
authors.lastname: Rowland
authors.forename: S
authors.initials: S
authors.lastname: Nørager
authors.forename: K F
authors.initials: KF
authors.lastname: Jensen
authors.forename: S
authors.initials: S
authors.lastname: Larsen
mesh_terms: D002462:Cell Membrane / Q000201:enzymology; D003460:Crystallization; D018360:Crystallography, X-Ray / Q000379:methods; D000090722:Dihydroorotate Dehydrogenase; D004926:Escherichia coli / Q000201:enzymology*; D046911:Macromolecular Substances; D010088:Oxidoreductases / Q000737:chemistry* / Q000302:isolation & purification; D044925:Oxidoreductases Acting on CH-CH Group Donors
chemical_list: D000090722:Dihydroorotate Dehydrogenase; D046911:Macromolecular Substances; D010088:Oxidoreductases; D044925:Oxidoreductases Acting on CH-CH Group Donors