The demonstration in rat liver cell sap of protein kinase and phosphoprotein phosphatase active on fructose-bisphosphatase

• A protein kinase active on fructose-bisphosphatase (D-fructose-1,6-bisphosphate 1-phosphohydrolase, EC 3.1.3.11) was demonstrated in rat liver cell sap. The protein kinase activity was stimulated by cyclic AMP and coincided with the activity of cyclic AMP-dependent protein kinase type I. In addition, three different peaks of phosphoprotein phosphatase active on [32P] phosphofructose-bisphosphatase were found on chromatography of rat liver cell sap on a DEAE-cellulose column. These phosphatases needed divalent cations for full activity. 5'-AMP, a negative modulator of fructose-bisphosphatase, had no effect on the phosphorylation-de-phosphorylation reactions of the enzyme. ATP and Ca2+ did not influence the dephosphorylation reaction of fructose-bisphosphatase.

Subject headings

NATURVETENSKAP  -- Biologi -- Biokemi och molekylärbiologi (hsv//swe)

NATURAL SCIENCES  -- Biological Sciences -- Biochemistry and Molecular Biology (hsv//eng)

Keyword

fructose-bisphosphatase

protein kinase

phosphoprotein phosphatase

Publication and Content Type

ref (subject category)

art (subject category)