title: An experiment eliminating the rotating carrier mechanism for the active transport of Ca ion in sarcoplasmic reticulum membranes.
abstract: An experiment has been carried out to test the rotating carrier mechanism of the translocation event in membrane transport. To the Ca-ATPase in intact sarcoplasmic reticulum membranes, 2,4-[3H]dinitrophenyl-cadaverine has been covalently attached by the action of the enzyme, transglutaminase. The binding of anti-2,4-dinitrophenyl antibodies to the 2,4-dinitrophenyl-modified membranes was found to have no effect on either the Ca-ATPase activity or the Ca ion transport rate of the membranes. These results rule out the rotating carrier mechanism in this system. A different scheme for the translocation process, the aggregate rearrangement mechanism, is discussed.
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D000818:Animals; D000937:Antigen-Antibody Reactions; D001693:Biological Transport, Active; D002118:Calcium / Q000378:metabolism*; D055598:Chemical Phenomena; D002621:Chemistry; D008954:Models, Biological; D009124:Muscle Proteins; D009578:Nitrobenzenes / Q000276:immunology; D011817:Rabbits; D012519:Sarcoplasmic Reticulum / Q000378:metabolism*
chemical_list: D009124:Muscle Proteins; D009578:Nitrobenzenes; D000251:Adenosine Triphosphatases; D002118:Calcium