title: Crystallization and preliminary X-ray crystallographic analysis of agkicetin-C from Deinagkistrodon acutus venom.
abstract: The crystallization and preliminary crystallographic analysis of agkicetin-C, a well known platelet glycoprotein Ib (GPIb) antagonist from the venom of Deinagkistrodon acutus found in Anhui Province, China is reported. Crystals of agkicetin-C suitable for structure determination were obtained from 1.8 M ammonium sulfate, 40 mM MES pH 6.5 with 2%(v/v) PEG 400. Interestingly, low buffer concentrations of MES seem to be necessary for crystal growth. The crystals of agkicetin-C belong to space group C2, with unit-cell parameters a = 177.5, b = 97.7, c = 106.8 A, beta = 118.5 degrees, and diffract to 2.4 A resolution. Solution of the phase problem by the molecular-replacement method shows that there are four agkicetin-C molecules in the asymmetric unit, with a VM value of 3.4 A3 Da(-1), which corresponds to a high solvent content of approximately 64%. Self-rotation function calculations show a single well defined non-crystallographic twofold axis with features that may represent additional elements of non-crystallographic symmetry.
authors.affiliation: Key Laboratory of Structural Biology, Chinese Academy of Sciences, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China.
authors.forename: Gufeng
authors.initials: G
authors.lastname: Xu
authors.forename: Qingqiu
authors.initials: Q
authors.lastname: Huang
authors.forename: Maikun
authors.initials: M
authors.lastname: Teng
authors.forename: Peng
authors.initials: P
authors.lastname: Liu
authors.forename: Yuhui
authors.initials: Y
authors.lastname: Dong
authors.forename: Liwen
authors.initials: L
authors.lastname: Niu
mesh_terms: D017836:Agkistrodon; D000818:Animals; D003435:Crotalid Venoms / Q000737:chemistry / Q000302:isolation & purification; D003460:Crystallization; D018360:Crystallography, X-Ray; D037181:Lectins, C-Type / Q000737:chemistry* / Q000302:isolation & purification; D010446:Peptide Fragments / Q000737:chemistry; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D014961:X-Ray Diffraction
chemical_list: D003435:Crotalid Venoms; D037181:Lectins, C-Type; D010446:Peptide Fragments; C093611:agkicetin