title: Structure of plastocyanin from the cyanobacterium Anabaena variabilis.
abstract: Plastocyanin from the cyanobacterium Anabaena variabilis was heterologously produced in Escherichia coli and purified. Plate-like crystals were obtained by crystallization in 1.15 M trisodium citrate and 7.67 mM sodium borate buffer pH 8.5. The crystals belong to the orthorhombic space group P2(1)2(1)2(1), with unit-cell parameters a = 67.85, b = 45.81, c = 63.41 Angstrom. The structure of the oxidized protein was solved to a resolution of 1.6 Angstrom using plastocyanin from Phormidium laminosum as a search model. Two molecules were found in the asymmetric unit. The electrostatic surface of the basic protein showed a large population of positively charged residues in the northern site, whereas the eastern site lacked the two strongly negatively charged patches. The copper ion was found to be relatively mobile and there were two distinct conformations of His61.
authors.affiliation: Department of Chemistry, The Technical University of Denmark, Building 207, DK-2800 Kgs. Lyngby, Denmark.
authors.forename: Lars
authors.initials: L
authors.lastname: Schmidt
authors.forename: Hans E M
authors.initials: HE
authors.lastname: Christensen
authors.forename: Pernille
authors.initials: P
authors.lastname: Harris
mesh_terms: D000595:Amino Acid Sequence; D017033:Anabaena / Q000378:metabolism*; D001881:Borates / Q000494:pharmacology; D002951:Citrates / Q000494:pharmacology; D003460:Crystallization; D018360:Crystallography, X-Ray; D004583:Electrons; D004926:Escherichia coli / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D008968:Molecular Conformation; D008969:Molecular Sequence Data; D010970:Plastocyanin / Q000737:chemistry*; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D017386:Sequence Homology, Amino Acid; D055672:Static Electricity
chemical_list: D001881:Borates; D002951:Citrates; C514290:trisodium citrate; D010970:Plastocyanin; C010634:sodium borate