title: Purification, crystallization and X-ray diffraction analysis of human synaptotagmin 1 C2A-C2B.
abstract: Synaptotagmin acts as the Ca(2+) sensor for neuronal exocytosis. The cytosolic domain of human synaptotagmin 1 is composed of tandem C2 domains: C2A and C2B. These C2 domains modulate the interaction of synaptotagmin with the phospholipid bilayer of the presynaptic terminus and effector proteins such as the SNARE complex. Human synaptotagmin C2A-C2B has been expressed as a glutathione-S-transferase fusion protein in Escherichia coli. The purification, crystallization and preliminary X-ray analysis of this protein are reported here. The crystals diffract to 2.7 A and belong to the orthorhombic space group P2(1)2(1)2(1), with unit-cell parameters a = 82.37, b = 86.31, c = 140.2 A. From self-rotation function analysis, there are two molecules in the asymmetric unit. The structure determination of the protein using this data is ongoing.
authors.affiliation: Department of Neuroscience and Cell Biology, The University of Texas Medical Branch, Galveston, TX 77555-0437, USA.
authors.forename: Miguel
authors.initials: M
authors.lastname: Montes
authors.forename: Kerry L
authors.initials: KL
authors.lastname: Fuson
authors.forename: R Bryan
authors.initials: RB
authors.lastname: Sutton
authors.forename: J Justin
authors.initials: JJ
authors.lastname: Robert
mesh_terms: D003460:Crystallization; D018360:Crystallography, X-Ray / Q000379:methods; D005982:Glutathione Transferase / Q000096:biosynthesis / Q000235:genetics; D006801:Humans; D017434:Protein Structure, Tertiary; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics; D050863:Synaptotagmin I / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification
chemical_list: D011993:Recombinant Fusion Proteins; D050863:Synaptotagmin I; D005982:Glutathione Transferase