Respiration and protein synthesis in Escherichia coli membrane-envelope fragments. VI. Solubilization and characterization of the electron transport chain.
Membranes obtained from Escherichia coli have been solubilized with deoxycholate. The solubilized dehydrogenases and cytochromes are not sedimented at 105,000 g. These components readily penetrate the "included space" of Sepharose 4B (Pharmacia Fine Chemicals Inc., Uppsala, Sweden) and polyacrylamide gels and have been fractionated on the basis of molecular size. Solubilization destroys nicotinamide adenine dinucleotide, reduced form (NADH) oxidase and D-lactate oxidase activities, but leaves an appreciable part of the original succinoxidase activity intact. Evidence for a succinate dehydrogenase-cytochrome b(1) complex is given. Menadione added to the solubilized preparation does not elicit NADH oxidase activity nor stimulate the existing succinoxidase activity, but does provoke an active D-lactate oxidase activity. This D-lactate oxidase activity, however, does not use cytochromes and is not sensitive to cyanide.
D001426:Bacterial Proteins / Q000096:biosynthesis* / Q000302:isolation & purification; D001647:Bile Acids and Salts; D002458:Cell Fractionation; D002462:Cell Membrane / Q000201:enzymology / Q000378:metabolism*; D002852:Chromatography, Ion Exchange; D003580:Cytochromes / Q000302:isolation & purification; D004579:Electron Transport; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007503:Iron Isotopes; D007521:Isocitrate Dehydrogenase / Q000302:isolation & purification; D007770:L-Lactate Dehydrogenase / Q000302:isolation & purification; D008291:Malate Dehydrogenase / Q000302:isolation & purification; D008722:Methods; D009243:NAD; D009249:NADP; D010088:Oxidoreductases / Q000302:isolation & purification; D010101:Oxygen Consumption; D013053:Spectrophotometry; D013385:Succinate Dehydrogenase / Q000302:isolation & purification
D001426:Bacterial Proteins; D001647:Bile Acids and Salts; D003580:Cytochromes; D007503:Iron Isotopes; D009243:NAD; D009249:NADP; D010088:Oxidoreductases; D007770:L-Lactate Dehydrogenase; D008291:Malate Dehydrogenase; D007521:Isocitrate Dehydrogenase; D013385:Succinate Dehydrogenase