title: Expression, purification and preliminary X-ray diffraction studies of the transcriptional factor PyrR from Bacillus halodurans.
abstract: The PyrR transcriptional regulator is widely distributed in bacteria. This RNA-binding protein is involved in the control of genes involved in pyrimidine biosynthesis, in which uridyl and guanyl nucleotides function as effectors. Here, the crystallization and preliminary X-ray diffraction analysis of two crystal forms of Bacillus halodurans PyrR are reported. One of the forms belongs to the monoclinic space group P2(1) with unit-cell parameters a = 59.7, b = 87.4, c = 72.1 A, beta = 104.4 degrees , while the other form belongs to the orthorhombic space group P22(1)2(1) with unit-cell parameters a = 72.7, b = 95.9, c = 177.1 A. Preliminary X-ray diffraction data analysis and molecular-replacement solution revealed the presence of four and six monomers per asymmetric unit; a crystallographic tetramer is formed in both forms.
authors.affiliation: Departamento de Bioquímica, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Circuito Exterior s/n, Ciudad Universitaria, Apartado Postal 70-243, Mexico City 04510, Mexico.
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Arreola
authors.forename: Anita
authors.initials: A
authors.lastname: Vega-Miranda
authors.forename: Armando
authors.initials: A
authors.lastname: Gómez-Puyou
authors.forename: Ruy
authors.initials: R
authors.lastname: Pérez-Montfort
authors.forename: Enrique
authors.initials: E
authors.lastname: Merino-Pérez
authors.forename: Alfredo
authors.initials: A
authors.lastname: Torres-Larios
mesh_terms: D001407:Bacillus / Q000737:chemistry*; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D001483:Base Sequence; D002850:Chromatography, Gel; D003001:Cloning, Molecular; D018360:Crystallography, X-Ray; D017931:DNA Primers; D004591:Electrophoresis, Polyacrylamide Gel; D008958:Models, Molecular; D010430:Pentosyltransferases / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D011487:Protein Conformation; D012097:Repressor Proteins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification
chemical_list: D001426:Bacterial Proteins; D017931:DNA Primers; D012097:Repressor Proteins; D010430:Pentosyltransferases; C098851:PyrR protein, bacteria