title: Metalloprotein active site structure determination: synergy between X-ray absorption spectroscopy and X-ray crystallography.
abstract: Structures of metalloprotein active sites derived from X-ray crystallography frequently contain chemical anomalies such as unexpected atomic geometries or elongated bond-lengths. Such anomalies are expected from the known errors inherent in macromolecular crystallography (ca. 0.1-0.2Å) and from the lack of appropriate restraints for metal sites which are often without precedent in the small molecule structure literature. Here we review the potential of X-ray absorption spectroscopy to provide information and perspective which could aid in improving the accuracy of metalloprotein crystal structure solutions. We also review the potential problem areas in analysis of the extended X-ray absorption fine structure (EXAFS) and discuss the use of density functional theory as another possible source of geometrical restraints for crystal structure analysis of metalloprotein active sites.
authors: Molecular and Environmental Sciences Research Group, Department of Geological Sciences, University of Saskatchewan, Saskatoon, SK, Canada S7N 5E2.
authors: Julien J H
authors: JJ
authors: Cotelesage
authors: M Jake
authors: MJ
authors: Pushie
authors: Pawel
authors: P
authors: Grochulski
authors: Ingrid J
authors: IJ
authors: Pickering
authors: Graham N
authors: GN
authors: George
mesh_terms: D020134:Catalytic Domain; D018360:Crystallography, X-Ray; D030562:Databases, Protein; D008667:Metalloproteins / Q000737:chemistry*; D056928:X-Ray Absorption Spectroscopy
chemical_list: D008667:Metalloproteins