title: Crystallization and preliminary crystallographic studies of five crystal forms of Escherichia coli L-asparaginase II (Asp90Glu mutant).
abstract: L-Asparaginase II from Escherichia coli with an Asp90Glu mutation in the active site has been crystallized in five polymorphic forms. Crystals of all polymorphs suitable for X-ray diffraction experiments were obtained by the vapour-diffusion method. Crystals of form I belong to the monoclinic system (space group C2), have unit-cell parameters a = 73.1, b = 133.1, c = 62.6 A, beta = 108.8 degrees and diffract to 2.27 A resolution. Three of the crystal forms are orthorhombic, with unit-cell parameters a = 225.4, b = 128.0, c = 62.6 A (form II, P2(1)2(1)2), a = 59.9, b = 71.2, c = 130.6 A (form III, primitive cell) and a = 73.8, b = 122.1, c = 124.2 A (form IV, P2(1)2(1)2(1) or P2(1)2(1)2); the crystals diffract to 2.33, 3.5 and 1.7 A, respectively. Polymorph V is trigonal, space group P3(1)21, with unit-cell parameters a = 123.1, c = 83.8 A; the crystals diffract to 2.65 A resolution.
authors.affiliation: Department of Macromolecular Physics, Faculty of Physics, A. Mickiewicz University, Poznañ, Poland. mkozak@amu.edu.pl
authors.forename: Maciej
authors.initials: M
authors.lastname: Kozak
authors.forename: Dominika
authors.initials: D
authors.lastname: Borek
authors.forename: Robert
authors.initials: R
authors.lastname: Janowski
authors.forename: Mariusz
authors.initials: M
authors.lastname: Jaskólski
mesh_terms: D001215:Asparaginase / Q000737:chemistry* / Q000235:genetics; D001224:Aspartic Acid / Q000235:genetics*; D003460:Crystallization; D018360:Crystallography, X-Ray; D004926:Escherichia coli / Q000201:enzymology*; D018698:Glutamic Acid / Q000235:genetics*; D009154:Mutation; D011487:Protein Conformation
chemical_list: D001224:Aspartic Acid; D018698:Glutamic Acid; D001215:Asparaginase