title: Expression, purification, crystallization and preliminary crystallographic analysis of phosphoserine aminotransferase from Bacillus alcalophilus.
abstract: Phosphoserine aminotransferase (PSAT; EC 2.6.1.52) from Bacillus alcalophilus, an obligatory alkalophile with optimum growth at pH 10.6, was overexpressed in Escherichia coli, purified and crystallized under two different conditions using the hanging-drop vapour-diffusion method. Crystals were obtained using trisodium citrate dihydrate or PEG 400 as a precipitating agent. Crystals grown in the presence of trisodium citrate belong to the orthorhombic space group C222(1), with unit-cell parameters a = 105.6, b = 136.6, c = 152.0 A, and those grown in the presence of PEG 400 belong to the orthorhombic space group P2(1)2(1)2, with unit-cell parameters a = 143.7, b = 84.3, c = 67.4 A. Complete data sets were collected to 1.7 and 1.6 A resolution, respectively, at 100 K using synchrotron radiation. Analysis of the structure of B. alcalophilus PSAT may reveal structural features that contribute to enzyme adaptability at high pH values.
authors.affiliation: Turku Centre for Biotechnology, University of Turku and Abo Academi University, PO Box 123, Turku 20521, Finland.
authors.forename: Anatoly P
authors.initials: AP
authors.lastname: Dubnovitsky
authors.forename: Evangelia G
authors.initials: EG
authors.lastname: Kapetaniou
authors.forename: Anastassios C
authors.initials: AC
authors.lastname: Papageorgiou
mesh_terms: D001407:Bacillus / Q000201:enzymology* / Q000235:genetics; D001426:Bacterial Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics; D003460:Crystallization; D018360:Crystallography, X-Ray; D004926:Escherichia coli / Q000378:metabolism; D015870:Gene Expression; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics; D017356:Synchrotrons; D000637:Transaminases / Q000096:biosynthesis / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification
chemical_list: D001426:Bacterial Proteins; D011994:Recombinant Proteins; D000637:Transaminases; C022393:phosphoserine aminotransferase