title: Characterization of the cytochromes occurring in Methanosarcina species.
abstract: Several members of the genus Methanosarcina were investigated by room-temperature and low-temperature difference spectroscopy for the presence of cytochromes. In combination with potentiometric titrations two membrane-bound b-cytochromes and one membrane-bound c-cytochrome could be detected in cells grown on methanol or trimethylamine. Very probably acetate-grown cells contained an additional cytochrome b. The midpoint potentials of the two b-type cytochromes were Em1 = -325 mV and Em2 = -183 mV, respectively. The additional b cytochrome formed during growth on acetate exhibited a midpoint potential of Em3 = -250 mV.
mesh_terms: D000085:Acetates / Q000378:metabolism; D002462:Cell Membrane / Q000032:analysis; D003080:Cold Temperature; D003573:Cytochrome b Group / Q000032:analysis*; D003574:Cytochrome c Group / Q000032:analysis*; D019605:Euryarchaeota / Q000032:analysis* / Q000502:physiology; D000432:Methanol / Q000378:metabolism; D010084:Oxidation-Reduction; D045332:Photosystem II Protein Complex; D011199:Potentiometry; D013053:Spectrophotometry
chemical_list: D000085:Acetates; D003573:Cytochrome b Group; D003574:Cytochrome c Group; D045332:Photosystem II Protein Complex; C019313:cytochrome b559; D000432:Methanol