Characterization of detergent-solubilized adenosine triphosphatase of chromaffin granule membranes.
Purified bovine chromaffin granule membranes contain approximately 24 pmol/mg protein (16 copies per granule) of an F1-like adenosine 5'-triphosphatase, and 340 pmol/mg protein (200 copies per granule) of a low-molecular weight protein which reacts covalently with dicyclohexylcarbodiimide. These co-purify on electrofocusing and exclusion chromatography and are apparently components of a proton-translocating adenosine triphosphatase complex, that is involved in maintaining the high concentration of catecholamines in the granules. The membranes contain another adenosine 5'-triphosphatase, of lower molecular weight, which is sensitive to inhibition by vanadate but relatively insensitive to dicyclohexylcarbodiimide. The function of this enzyme is unknown.
D000251:Adenosine Triphosphatases / Q000378:metabolism*; D000818:Animals; D002352:Carrier Proteins / Q000378:metabolism; D002417:Cattle; D002499:Centrifugation, Density Gradient; D002837:Chromaffin Granules / Q000201:enzymology*; D002838:Chromaffin System / Q000201:enzymology*; D004591:Electrophoresis, Polyacrylamide Gel; D007425:Intracellular Membranes / Q000201:enzymology*; D007525:Isoelectric Focusing; D008970:Molecular Weight
D002352:Carrier Proteins; D000251:Adenosine Triphosphatases