title: Crystallization and preliminary X-ray diffraction analysis of inositol 1,3,4,5,6-pentakisphosphate kinase from Arabidopsis thaliana.
abstract: Inositol 1,3,4,5,6-pentakisphosphate kinase (IP(5) 2-K) is an enzyme involved in inositol metabolism that synthesizes IP(6) (inositol 1,2,3,4,5,6-hexakisphosphate) from inositol 1,3,4,5,6-pentakisphosphate (IP(5)) and ATP. IP(6) is the major phosphorus reserve in plants, while in mammals it is involved in multiple cellular events such as DNA editing and chromatin remodelling. In addition, IP(6) is the precursor of other highly phosphorylated inositols which also play highly relevant roles. IP(5) 2-K is the only enzyme that phosphorylates the 2-OH axial position of the inositide and understanding its molecular mechanism of substrate specificity is of great interest in cell biology. IP(5) 2-K from Arabidopsis thaliana has been expressed in Escherichia coli as two different fusion proteins and purified. Both protein preparations yielded crystals of different quality, always in the presence of IP(6). The best crystals obtained for X-ray crystallographic analysis belonged to space group P2(1)2(1)2(1), with unit-cell parameters a = 58.124, b = 113.591, c = 142.478 A. Several diffraction data sets were collected for the native enzyme and two heavy-atom derivatives using a synchrotron source.
authors.affiliation: Grupo de Cristalografía Macromolecular y Biología Estructural, Instituto de Química-Física 'Rocasolano', CSIC, Serrano 119, 28006 Madrid, Spain.
authors.forename: Jose Ignacio
authors.initials: JI
authors.lastname: Baños-Sanz
authors.forename: Maider
authors.initials: M
authors.lastname: Villate
authors.forename: Julia
authors.initials: J
authors.lastname: Sanz-Aparicio
authors.forename: Charles Alistair
authors.initials: CA
authors.lastname: Brearley
authors.forename: Beatriz
authors.initials: B
authors.lastname: González
mesh_terms: D017360:Arabidopsis / Q000201:enzymology; D029681:Arabidopsis Proteins / Q000737:chemistry; D003460:Crystallization; D018360:Crystallography, X-Ray; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000737:chemistry*
chemical_list: D029681:Arabidopsis Proteins; D017853:Phosphotransferases (Alcohol Group Acceptor); C502806:inositol 1,3,4,5,6-pentakisphosphate 2-kinase