title: An ensemble of crystallographic models enables the description of novel bromate-oxoanion species trapped within a protein crystal.
abstract: Only a few protein-oxoanion crystal complexes have been described to date. Here, the structure of a protein soaked in a bromate solution has been determined to a resolution of 1.25 A and refined to final overall R/R(free) values of 18.04/21.3 (isotropic) and 11.25/14.67 (anisotropic). In contrast to the single-model approach, refinement of an ensemble of ten models enabled us to determine variances and statistically evaluate bond-length distances and angles in the oxoanions. In total, nine bromate positions, including two BrO(3)(-) x HBrO(3) dimer species, have been identified on the basis of the anomalous signal of the Br atoms. For all bromate ions, the main-chain amide atoms of the protein were identified as the dominant binding positions, a useful property in any experimental phase-determination experiment.
authors.affiliation: Department of Recombinant Expression and Structural Biology, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Flemingovo namesti 2, CZ-16637 Praha 6, Czech Republic. ondracek@img.cas.cz
authors.forename: Jan
authors.initials: J
authors.lastname: Ondrácek
authors.forename: Jeroen R
authors.initials: JR
authors.lastname: Mesters
mesh_terms: D000577:Amides / Q000737:chemistry; D000838:Anions / Q000737:chemistry*; D016880:Anisotropy; D001959:Bromates / Q000737:chemistry*; D003460:Crystallization; D018360:Crystallography, X-Ray; D019281:Dimerization; D004583:Electrons; D006860:Hydrogen Bonding; D008958:Models, Molecular; D008962:Models, Theoretical; D008968:Molecular Conformation; D009113:Muramidase / Q000737:chemistry; D011506:Proteins / Q000737:chemistry*
chemical_list: D000577:Amides; D000838:Anions; D001959:Bromates; D011506:Proteins; D009113:Muramidase