title: Purification and characterization of cytochrome c oxidase from rat liver mitochondria.
abstract: Cytochrome c oxidase has been purified from rat liver mitochondria using affinity chromatography. The preparation contains 10.5 to 13.4 nmol of heme a + a3 per mg of protein and migrates as a single band during polyacrylamide gel electrophoresis under nondissociating conditions. It has a heme a/a3 ratio of 1.12 and is free of cytochromes b, c, and c1 as well as the enzymes, NADH dehydrogenase, succinic dehydrogenase, coenzyme Q-cytochrome c reductase, and ATPase. The enzyme preparation consists of six polypeptides having apparent Mr of 66,000, 39,000, 23,000, 14,000, 12,500 and 10,000 as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The peptide composition is similar to those found for cytochrome c oxidases from other systems. The enzymatic activity of the purified enzyme is completely inhibited by carbon monoxide or cyanide, partially inhibited by Triton X-100 and dramatically enhanced by Tween 80 or phospholipids.
mesh_terms: D000818:Animals; D002248:Carbon Monoxide; D003576:Electron Transport Complex IV / Q000302:isolation & purification / Q000378:metabolism*; D005260:Female; D007700:Kinetics; D008297:Male; D008930:Mitochondria, Liver / Q000201:enzymology*; D008970:Molecular Weight; D010084:Oxidation-Reduction; D051381:Rats; D013053:Spectrophotometry
chemical_list: D002248:Carbon Monoxide; D003576:Electron Transport Complex IV