Selective incorporation of membrane proteins into proteoliposomes of different compositions.
1. Cytochrome oxidase was incorporated into preformed liposomes containing phosphatidylserine. When confronted with a mixture of liposomes, some containing phosphatidylserine and some without it, the enzyme was incorporated only into the phosphatidylserine-containing liposomes. 2. The hydrophobic proteins of the oligomycin-sensitive ATPase incubated in the presence of a mixture of liposomes with and without cytochrome oxidase were preferentially incorporated into cytochrome oxidase-containing liposomes. This selectivity was abolished by either cytochrome c or ascorbate. 3. Cytochrome oxidase incubated in the presence of a mixture of liposomes with and without the hydrophobic proteins of the ATPase was preferentially incorporated into liposomes that did not contain the hydrophobic proteins. 4. Cytochrome oxidase and the oligomycin-sensitive ATPase were preferentially incorporated into pure liposomes over bacteriorhodopsin-containing vesicles. 5. Reduced coenzyme Q (QH2)-cytochrome c reductase was incorporated randomly when incubated in the presence of a mixture of pure liposomes and liposomes containing the hydrophobic proteins of the ATPase complex. 6. The significance of the incorporation procedure as a model for membrane biogenesis is discussed.
D000251:Adenosine Triphosphatases / Q000378:metabolism; D001436:Bacteriorhodopsins / Q000378:metabolism; D003579:Cytochrome Reductases / Q000378:metabolism; D003576:Electron Transport Complex IV / Q000378:metabolism; D008081:Liposomes / Q000378:metabolism*; D008563:Membrane Lipids / Q000378:metabolism*; D008565:Membrane Proteins / Q000378:metabolism*; D008567:Membranes, Artificial; D010713:Phosphatidylcholines / Q000378:metabolism; D010714:Phosphatidylethanolamines / Q000378:metabolism; D010718:Phosphatidylserines / Q000378:metabolism; D012995:Solubility; D013329:Structure-Activity Relationship
D008081:Liposomes; D008563:Membrane Lipids; D008565:Membrane Proteins; D008567:Membranes, Artificial; D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines; D010718:Phosphatidylserines; D001436:Bacteriorhodopsins; D003579:Cytochrome Reductases; D003576:Electron Transport Complex IV; D000251:Adenosine Triphosphatases