title: Crystallization and preliminary X-ray diffraction analysis of an oxidized state of Ohr from Xylella fastidiosa.
abstract: Xylella fastidiosa organic hydroperoxide-resistance protein (Ohr) is a dithiol-dependent peroxidase that is widely conserved in several pathogenic bacteria with high affinity for organic hydroperoxides. The protein was crystallized using the hanging-drop vapour-diffusion method in the presence of PEG 4000 as precipitant after treatment with organic peroxide (t-butyl hydroperoxide). X-ray diffraction data were collected to a maximum resolution of 1.8 A using a synchrotron-radiation source. The crystal belongs to the hexagonal space group P6(5)22, with unit-cell parameters a = b = 87.66, c = 160.28 A. The crystal structure was solved by molecular-replacement methods. The enzyme has a homodimeric quaternary structure similar to that observed for its homologue from Pseudomonas aeruginosa, but differs from the previous structure as the active-site residue Cys61 is oxidized. Structure refinement is in progress.
authors.affiliation: Departamento de Biologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão 277, São Paulo SP, Brazil.
authors.forename: Marcos Antonio
authors.initials: MA
authors.lastname: de Oliveira
authors.forename: Luis Eduardo Soares
authors.initials: LE
authors.lastname: Netto
authors.forename: Francisco Javier
authors.initials: FJ
authors.lastname: Medrano
authors.forename: João Alexandre Ribeiro Gonçalves
authors.initials: JA
authors.lastname: Barbosa
authors.forename: Simone Vidigal
authors.initials: SV
authors.lastname: Alves
authors.forename: José Renato Rosa
authors.initials: JR
authors.lastname: Cussiol
authors.forename: Beatriz Gomes
authors.initials: BG
authors.lastname: Guimarães
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry*; D001665:Binding Sites; D003460:Crystallization; D003545:Cysteine / Q000737:chemistry; D019281:Dimerization; D010100:Oxygen / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry; D011487:Protein Conformation; D020836:Protein Structure, Quaternary; D020560:Proteobacteria / Q000378:metabolism*; D012997:Solvents / Q000737:chemistry; D014961:X-Ray Diffraction / Q000379:methods*; D020122:tert-Butylhydroperoxide / Q000737:chemistry
chemical_list: D001426:Bacterial Proteins; D012997:Solvents; C112257:organic hydroperoxide resistance protein, Xanthomonas campestris; D011092:Polyethylene Glycols; D020122:tert-Butylhydroperoxide; D003545:Cysteine; D010100:Oxygen