Stabilization of glucose-6-phosphatase activity by a 21 000-dalton hepatic microsomal protein.
Hepatic microsomal glucose-6-phosphatase activity was rendered extremely unstable by a variety of techniques: (a) incubation at pH 5.0; (b) extraction of the microsomal fraction in the presence of 1% Lubrol; (c) various purification procedures. These techniques all result in the removal of a 21 kDa polypeptide from the fraction containing glucose-6-phosphatase activity. The 21 kDa protein was purified to apparent homogeneity by solubilization in the detergent Lubrol 12A-9 and chromatography on Fractogel TSK DEAE-650(S) and centrifugation at 105 000 g. The 21 kDa protein stabilizes glucose-6-phosphatase activity, whereas other purified hepatic microsomal proteins do not. The 21 kDa protein appears to be a potential regulator of glucose-6-phosphatase activity.
D000818:Animals; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D005952:Glucose-6-Phosphatase / Q000037:antagonists & inhibitors / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D005779:Immunodiffusion; D008862:Microsomes, Liver / Q000201:enzymology*; D010455:Peptides / Q000302:isolation & purification; D011817:Rabbits
D010455:Peptides; D005952:Glucose-6-Phosphatase