title: Crystal structure of the complex of concanavalin A and tripeptide.
abstract: The X-ray structure analysis of a cross-linked crystal of concanavalin A soaked with the tripeptide molecule as the probe molecule showed electron density corresponding to full occupation in the binding pocket. The site lies on the surface of concanavalin A and is surrounded by three symmetry-related molecules. The crystal structure of the tripeptide complex was refined at 2.4-A resolution to an R-factor of 17.5%, (Rfree factor of 23.7%), with an RMS deviation in bond distances of 0.01 A. The model includes all 237 residue of concanavalin A, 1 manganese ion, 1 calcium ion, 161 water molecules, 1 glutaraldehyde molecule, and 1 tripeptide molecule. This X-ray structure analysis also provides an approach to mapping the binding surface of crystalline protein with a probe molecule that is dissolved in a mixture of organic solvent with water or in neat organic solvent but is hardly dissolved in aqueous solution.
authors.affiliation: Department of Chemistry, Peking University, Beijing, China.
authors.forename: Z
authors.initials: Z
authors.lastname: Zhang
authors.forename: M
authors.initials: M
authors.lastname: Qian
authors.forename: Q
authors.initials: Q
authors.lastname: Huang
authors.forename: Y
authors.initials: Y
authors.lastname: Jia
authors.forename: Y
authors.initials: Y
authors.lastname: Tang
authors.forename: K
authors.initials: K
authors.lastname: Wang
authors.forename: D
authors.initials: D
authors.lastname: Cui
authors.forename: M
authors.initials: M
authors.lastname: Li
mesh_terms: D001665:Binding Sites; D003208:Concanavalin A / Q000737:chemistry* / Q000378:metabolism*; D018360:Crystallography, X-Ray; D008958:Models, Molecular; D010455:Peptides / Q000737:chemistry / Q000378:metabolism*; D011487:Protein Conformation
chemical_list: D010455:Peptides; D003208:Concanavalin A