title: The EPR spectra of the cytochrome b-c1 complex of Rhodopseudomonas sphaeroides.
abstract: The purified cytochrome b-c1 complex of Rhodopseudomonas sphaeroides has two b cytochromes distinguishable by optical, thermodynamic and electron paramagnetic resonance criteria (gz values are approximately equal to 3.75 and approximately equal to 3.4). EPR features typical of a Rieske iron sulfur cluster (g values of 2.03 1.90 and 1.81) and a c1 type cytochrome (g approximately equal to 3.4) were also observed. The b and c1 cytochromes were individually purified from the complex. The cytochrome c1 retained its native EPR spectrum. The b cytochrome lost over 90% of the intensity from the 'b566 type' heme site (g approximately equal to 3.75), while the 'b561 type' heme site (g approximately equal to 3.4) retained its native EPR spectrum.
mesh_terms: D001205:Ascorbic Acid / Q000494:pharmacology; D003573:Cytochrome b Group / Q000302:isolation & purification; D003575:Cytochromes c1 / Q000302:isolation & purification; D004578:Electron Spin Resonance Spectroscopy; D014450:Electron Transport Complex III; D009097:Multienzyme Complexes / Q000302:isolation & purification; D010084:Oxidation-Reduction; D011199:Potentiometry; D011808:Quinone Reductases / Q000302:isolation & purification; D012242:Rhodobacter sphaeroides / Q000201:enzymology*
chemical_list: D003573:Cytochrome b Group; D009097:Multienzyme Complexes; D003575:Cytochromes c1; D011808:Quinone Reductases; D014450:Electron Transport Complex III; D001205:Ascorbic Acid