title: Crystallization and preliminary X-ray analysis of human D-dopachrome tautomerase.
abstract: D-Dopachrome tautomerase catalyzes the conversion of D-dopachrome to 5,6-dihydroxyindole. This protein has amino acid sequence homology with that of macrophage migration inhibitory factor (MIF), suggesting a pathophysiological role of this protein in inflammatory and immunological events. We previously determined the tertiary structure of MIF and revealed the functional and evolutional relationships of this protein to isomerase. However, the reaction mechanism of both proteins associated with the inflammatory response, immune system, or tautomerase activities in vitro have not yet been clarified. The tertiary structure of D-dopachrome tautomerase would provide insight into the molecular function and the mechanism of these proteins. In this study, we crystallized human D-dopachrome tautomerase by a hanging-drop vapor diffusion method. The crystals belong to the trigonal space group P3, with unit cell dimensions a = b = 84.2 A and c = 41.0 A. They contain three (or two) monomers in the asymmetric unit, corresponding to a VM value of 2.21 (or 3.32) A3 Da-1. The best crystals diffract X-ray to 1.6 A resolution using a synchrotron radiation source. Crystallization of the selenomethionyl derivative of the protein for applying the multiwavelength anomalous diffraction method was also successful.
authors.affiliation: Division of Biological Sciences, Graduate School of Science, Hokkaido University, Sapporo, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Sugimoto
authors.forename: M
authors.initials: M
authors.lastname: Taniguchi
authors.forename: A
authors.initials: A
authors.lastname: Nakagawa
authors.forename: I
authors.initials: I
authors.lastname: Tanaka
authors.forename: M
authors.initials: M
authors.lastname: Suzuki
authors.forename: J
authors.initials: J
authors.lastname: Nishihira
mesh_terms: D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange; D003001:Cloning, Molecular; D003460:Crystallization; D018360:Crystallography, X-Ray / Q000379:methods; D017931:DNA Primers; D004926:Escherichia coli; D006801:Humans; D019746:Intramolecular Oxidoreductases / Q000737:chemistry* / Q000302:isolation & purification; D016133:Polymerase Chain Reaction; D017434:Protein Structure, Tertiary; D011994:Recombinant Proteins / Q000737:chemistry / Q000302:isolation & purification
chemical_list: D017931:DNA Primers; D011994:Recombinant Proteins; D019746:Intramolecular Oxidoreductases; C042501:dopachrome isomerase