Chromatographic resolution and characterization of different casein phosphatase activities from the cytosolic compartment of rat erythrocytes.
Casein phosphatase activity in the cytosol of erythrocytes, taken from 1-month-old rats, is associated with three chromatographically distinct peaks: E1, E2 and E3. The dominant molecular form was E3 phosphatase, molecular weight 180,000 dalton, which increased in the cytosol of erythrocytes as compared to the value found in the same compartments of reticulocytes. The enzyme had the pH optimum at 6.5 and seemed to be positively cooperative with respect to substrate and negatively cooperative with respect to pyrophosphate, the most potent inhibitor. E1 and E2 casein phosphatases seem to be remnant activities in erythrocytes as compared to the values found in the cytosol of reticulocytes.
D000818:Animals; D002848:Chromatography, DEAE-Cellulose; D002850:Chromatography, Gel; D003035:Cobalt / Q000494:pharmacology; D003600:Cytosol / Q000201:enzymology; D004912:Erythrocytes / Q000201:enzymology*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008970:Molecular Weight; D051381:Rats; D011919:Rats, Inbred Strains; D013379:Substrate Specificity
D003035:Cobalt; C018021:cobaltous chloride