title: Crystallization and X-ray diffraction analysis of ornithine cyclodeaminase from Pseudomonas putida.
abstract: Ornithine cyclodeaminase (OCD) is a member of the micro-crystallin protein family, the biological activity of which is the conversion of L-ornithine to L-proline and ammonia. In order to elucidate the functional groups of this enzyme that are involved in catalysis, the crystallization of OCD from Pseudomonas putida was undertaken. Using microbatch-under-oil screening at the high-throughput crystallization laboratory (HTC) at the Hauptman-Woodward Medical Research Institute Inc. (HWI Buffalo, NY, USA), numerous crystallization conditions were rapidly identified. Several conditions could be reproduced on a larger scale as vapor-diffusion experiments in-house. The best diffraction-quality crystals were obtained from solutions of 40%(v/v) 2-methyl-2,4-pentanediol buffered at pH 6.0 with 0.1 M MES and diffracted X-rays to 1.68 A resolution. Crystals belonged to space group P2(1)2(1)2(1), with unit-cell parameters a = 70.0, b = 78.3, c = 119.4 A. The V(M) was 2.1 A(3) Da(-1), corresponding to 42% solvent, which is consistent with two 38.5 kDa molecules per asymmetric unit. The structure determination is under way using experimental phasing methods.
authors.affiliation: Department of Biochemistry and Biophysics, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA.
authors.forename: Shabnam
authors.initials: S
authors.lastname: Alam
authors.forename: Susan C
authors.initials: SC
authors.lastname: Wang
authors.forename: Frank J
authors.initials: FJ
authors.lastname: Ruzicka
authors.forename: Perry A
authors.initials: PA
authors.lastname: Frey
authors.forename: Joseph E
authors.initials: JE
authors.lastname: Wedekind
mesh_terms: D000642:Ammonia-Lyases / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D001331:Automation; D003001:Cloning, Molecular; D003460:Crystallization; D018360:Crystallography, X-Ray; D011487:Protein Conformation; D016958:Pseudomonas putida / Q000201:enzymology*; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism
chemical_list: D011994:Recombinant Proteins; D000642:Ammonia-Lyases; C021914:ornithine cyclodeaminase