title: An NMR investigation of electron transfer in the copper-protein, plastocyanin.
abstract: 1. The proton NMR spectra of oxidised and reduced French bean plastocyanin have been recorded on a 270 MHz pulsed spctrometer. 2. The spectrum of a mixture containing the protein in the paramagnetic Cu(II) and diamagnetic Cu(I) states is a superposition of the separate spectra. When ferrirate spectra. 3. The results show that self-exchange between Cu(II)- and Cu(I)-plastocyanin is slow on the NMR time scale (kex less than 2-10(4) M-1-s-1 at 50 degrees C), and that electron transfer in the presence of ferricyanide is rapid (k greater than 1-10(5) M-1-s-1).
mesh_terms: D003300:Copper / Q000032:analysis; D004579:Electron Transport; D004735:Energy Transfer; D006863:Hydrogen-Ion Concentration; D009682:Magnetic Resonance Spectroscopy; D008433:Mathematics; D010084:Oxidation-Reduction; D010940:Plant Proteins; D010944:Plants / Q000032:analysis; D010970:Plastocyanin / Q000302:isolation & purification; D011485:Protein Binding; D011487:Protein Conformation
chemical_list: D010940:Plant Proteins; D003300:Copper; D010970:Plastocyanin