title: Cloning, purification, crystallization and preliminary X-ray analysis of the receiver domain of the histidine kinase CKI1 from Arabidopsis thaliana.
abstract: The receiver domain (RD) of a sensor histidine kinase (HK) catalyses the transphosphorylation reaction during the action of HKs in hormonal and abiotic signalling in plants. Crystals of the recombinant RD of the Arabidopsis thaliana HK CYTOKININ-INDEPENDENT1 (CKI1(RD)) have been obtained by the hanging-drop vapour-diffusion method using ammonium sulfate as a precipitant and glycerol as a cryoprotectant. The crystals diffracted to approximately 2.4 A resolution on beamline BW7B of the DORIS-III storage ring. The diffraction improved significantly after the use of a non-aqueous cryoprotectant. Crystals soaked in Paratone-N diffracted to at least 2.0 A resolution on beamline BW7B and their mosaicity decreased more than tenfold. The crystals belonged to space group C222(1), with unit-cell parameters a = 54.46, b = 99.82, c = 79.94 A. Assuming the presence of one molecule of the protein in the asymmetric unit gives a Matthews coefficient V(M) of 2.33 A(3) Da(-1). A molecular-replacement solution has been obtained and structure refinement is in progress.
authors.affiliation: Department of Functional Genomics and Proteomics, Institute of Experimental Biology, Masaryk University, Kamenice, Brno, Czech Republic.
authors.forename: Tomás
authors.initials: T
authors.lastname: Klumpler
authors.forename: Blanka
authors.initials: B
authors.lastname: Pekárová
authors.forename: Jaromír
authors.initials: J
authors.lastname: Marek
authors.forename: Petra
authors.initials: P
authors.lastname: Borkovcová
authors.forename: Lubomír
authors.initials: L
authors.lastname: Janda
authors.forename: Jan
authors.initials: J
authors.lastname: Hejátko
mesh_terms: D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics; D029681:Arabidopsis Proteins / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D003001:Cloning, Molecular; D003460:Crystallization; D018360:Crystallography, X-Ray; D000071677:Histidine Kinase; D011494:Protein Kinases / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D011494:Protein Kinases; D000071677:Histidine Kinase; C101990:CKI1 protein, Arabidopsis