title: The first solution structure of a paramagnetic copper(II) protein: the case of oxidized plastocyanin from the cyanobacterium Synechocystis PCC6803.
abstract: The NMR solution structure of oxidized plastocyanin from the cyanobacterium Synechocystis PCC6803 is here reported. The protein contains paramagnetic copper(II), whose electronic relaxation times are quite unfavorable for NMR solution studies. The structure has been solved on the basis of 1041 meaningful NOESY cross-peaks, 18 1D NOEs, 26 T(1) values, 96 dihedral angle constraints, and 18 H-bonds. The detection of broad hyperfine-shifted signals and their full assignment allowed the identification of the copper(II) ligands and the determination of the Cu-S-C-H dihedral angle for the coordinated cysteine. The global root-mean-square deviation from the mean structure for the solution structure family is 0.72 +/- 0.14 and 1.16 +/- 0.17 A for backbone and heavy atoms, respectively. The structure is overall quite satisfactory and represents a breakthrough, in that it includes paramagnetic copper proteins among the metalloproteins for which solution structures can be afforded. The comparison with the available X-ray structure of a triple mutant is also performed.
authors.affiliation: Contribution from the Magnetic Resonance Center, University of Florence, Via L. Sacconi, 6, 50019 Sesto Fiorentino, Italy.
authors.forename: I
authors.initials: I
authors.lastname: Bertini
authors.forename: S
authors.initials: S
authors.lastname: Ciurli
authors.forename: A
authors.initials: A
authors.lastname: Dikiy
authors.forename: C O
authors.initials: CO
authors.lastname: Fernàndez
authors.forename: C
authors.initials: C
authors.lastname: Luchinat
authors.forename: N
authors.initials: N
authors.lastname: Safarov
authors.forename: S
authors.initials: S
authors.lastname: Shumilin
authors.forename: A J
authors.initials: AJ
authors.lastname: Vila
mesh_terms: D000595:Amino Acid Sequence; D000458:Cyanobacteria / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D010084:Oxidation-Reduction; D010970:Plastocyanin / Q000737:chemistry*; D012996:Solutions
chemical_list: D012996:Solutions; D010970:Plastocyanin