title: Escherichia coli B gamma-glutamylcysteine synthetase: modification, purification, crystallization and preliminary crystallographic analysis.
abstract: Escherichia coli B gamma-glutamylcysteine synthetase (gammaGCS) catalyzes the ATP-dependent coupling of L-Glu and L-Cys to form the glutathione precursor gamma-L-Glu-Cys and is a target for development of potential therapeutic agents. By introducing four point mutations of surface-exposed cysteine residues to serine, the gammaGCS was purified to homogeneity; single crystals have been obtained using the hanging-drop vapour-diffusion method with sodium formate. The gammaGCS crystal diffracted to 2.8 A and belongs to space group R3, with unit-cell parameters a = b = 326.7, c = 103.9 A.
authors.affiliation: Department of Bioscience, Fukui Prefectural University, Fukui 910-1195, Japan. hibi@fpu.ac.jp
authors.forename: Takao
authors.initials: T
authors.lastname: Hibi
authors.forename: Hiromoto
authors.initials: H
authors.lastname: Hisada
authors.forename: Toru
authors.initials: T
authors.lastname: Nakatsu
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Kato
authors.forename: Jun'ichi
authors.initials: J
authors.lastname: Oda
mesh_terms: D003460:Crystallization; D018360:Crystallography, X-Ray; D003545:Cysteine / Q000235:genetics; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics; D005721:Glutamate-Cysteine Ligase / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D008301:Maleimides / Q000737:chemistry; D009154:Mutation; D011487:Protein Conformation; D012694:Serine / Q000235:genetics; D013438:Sulfhydryl Compounds / Q000737:chemistry
chemical_list: D008301:Maleimides; D013438:Sulfhydryl Compounds; D012694:Serine; C000245:N-(4-(2-benzimidazolyl)phenyl)maleimide; D005721:Glutamate-Cysteine Ligase; D003545:Cysteine