title: Purification, crystallization and preliminary X-ray analysis of an aminoacylhistidine dipeptidase (PepD) from Vibrio alginolyticus.
abstract: The aminoacylhistidine dipeptidase (PepD) protein encoded by Vibrio alginolyticus pepD was successfully overexpressed and characterized and the putative active-site residues responsible for metal binding and catalysis were identified. The purified enzyme contained two zinc ions per monomer. The recombinant dipeptidase enzyme, which was identified as a homodimer in solution, exhibited broad substrate specificity for Xaa-His dipeptides, with highest activity towards the His-His dipeptide. The purified protein was crystallized using the hanging-drop vapour-diffusion method. Preliminary crystallographic analysis showed that the crystal belonged to space group P6(1) or P6(5), with unit-cell parameters a = b = 80.42, c = 303.11 A. The crystal contained two molecules per asymmetric unit and the predicted solvent content was 53.4%.
authors.affiliation: Department of Biological Science and Technology, National Chiao Tung University, Hsinchu, Taiwan.
authors.forename: Chin Yuan
authors.initials: CY
authors.lastname: Chang
authors.forename: Yin Cheng
authors.initials: YC
authors.lastname: Hsieh
authors.forename: Ting Yi
authors.initials: TY
authors.lastname: Wang
authors.forename: Chun Jung
authors.initials: CJ
authors.lastname: Chen
authors.forename: Tung Kung
authors.initials: TK
authors.lastname: Wu
mesh_terms: D003460:Crystallization; D018360:Crystallography, X-Ray; D004150:Dipeptidases / Q000737:chemistry* / Q000302:isolation & purification*; D004591:Electrophoresis, Polyacrylamide Gel; D044149:Vibrio alginolyticus / Q000201:enzymology*
chemical_list: D004150:Dipeptidases; C038937:dipeptidase