title: 1H one-dimensional and two-dimensional NMR studies of the ferricytochrome c 551 from Rhodocyclus gelatinosus.
abstract: 1H two-dimensional NMR spectroscopy has been applied to the oxidized form of cytochrome c 551 from Rhodocyclus gelatinosus, which is paramagnetic with S = 1/2. The investigation has allowed a complete and unambiguous assignment of the heme protons and some residues around the heme. We have learned that: the conformation of the axial methionine is equal to that of horse heart cytochrome c and different from two isoenzymes of the same cytochrome c 551 from a different strain; pKa of 6.6 +/- 0.3 has been detected through the shift variations of seventh propionate protons. The detailed differences with other cytochromes c in the hyperfine shifts are discussed.
authors.affiliation: Department of Chemistry, University of Florence, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Banci
authors.forename: I
authors.initials: I
authors.lastname: Bertini
authors.forename: M T
authors.initials: MT
authors.lastname: Cambria
authors.forename: F
authors.initials: F
authors.lastname: Capozzi
authors.forename: A
authors.initials: A
authors.lastname: Dikiy
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins; D003574:Cytochrome c Group / Q000737:chemistry*; D006859:Hydrogen; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D010649:Phenylalanine / Q000032:analysis; D011487:Protein Conformation; D012244:Rhodospirillaceae / Q000378:metabolism*; D013816:Thermodynamics; D014364:Tryptophan / Q000032:analysis; D014961:X-Ray Diffraction
chemical_list: D001426:Bacterial Proteins; D003574:Cytochrome c Group; D010649:Phenylalanine; D006859:Hydrogen; D014364:Tryptophan; C017167:cytochrome C(551)