title: The phosphoprotein intermediate of a Ca2+ transport ATPase in rat liver endoplasmic reticulum.
abstract: Smooth endoplasmic reticulum vesicles from rat liver display an ATP-supported Ca2+ transport which is mediated by a (Ca2+ + Mg2+)-ATPase. During the catalytic cycle the terminal phosphate from ATP is incorporated to form an acid-precipitable reaction product(118 000-Mr in SDS-gel electrophoresis) with stability characteristics of an acylphosphate. Comparative studies with sarcoplasmic reticulum vesicles from fast-twitch skeletal muscle suggest that the 118 000-Mr phosphopeptide may be identified with the phosphorylated reaction intermediate of a Ca2+ transport ATPase in endoplasmic reticulum, similar to that in sarcoplasmic reticulum of muscle.
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D000818:Animals; D001693:Biological Transport, Active; D017301:Ca(2+) Mg(2+)-ATPase; D002118:Calcium / Q000378:metabolism; D000252:Calcium-Transporting ATPases / Q000302:isolation & purification / Q000378:metabolism*; D004721:Endoplasmic Reticulum / Q000201:enzymology*; D007700:Kinetics; D008099:Liver / Q000201:enzymology*; D008297:Male; D008970:Molecular Weight; D010750:Phosphoproteins / Q000302:isolation & purification / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D010750:Phosphoproteins; D000251:Adenosine Triphosphatases; D017301:Ca(2+) Mg(2+)-ATPase; D000252:Calcium-Transporting ATPases; D002118:Calcium