Fructose-6-phosphate,2-kinase activity in human erythrocytes.
The hemolysate partially purified from human red cells was demonstrated to be capable of synthesizing fructose-2,6-bisphosphate (F-2,6-P2) from fructose-6-phosphate in the presence of adenosine triphosphate (ATP) indicating that human red cells contain fructose-6-phosphate,2-kinase. The effect of F-2,6-P2 on the rate-limiting enzymes of glycolysis, ie, hexokinase, phosphofructokinase (PFK), and pyruvate kinase, has also been examined. PFK was activated by this metabolite and the half-maximum activation was obtained at a concentration of 10(-7) mol/L. Neither hexokinase nor pyruvate kinase was affected by F-2,6-P2. These results suggest that human erythrocytes may contain this metabolite as one of the positive effectors for PFK.
Fujii
S
S
Third Department of Internal Medicine, Yamaguchi University School of Medicine, Ube, Japan.
Matsuda
M
M
Okuya
S
S
Yoshizaki
Y
Y
Miura-Kora
Y
Y
Kaneko
T
T
D004912:Erythrocytes / Q000201:enzymology*; D006593:Hexokinase / Q000097:blood; D006801:Humans; D009994:Osmolar Concentration; D010732:Phosphofructokinase-1 / Q000097:blood; D025481:Phosphofructokinase-2; D010770:Phosphotransferases / Q000097:blood* / Q000494:pharmacology; D011770:Pyruvate Kinase / Q000097:blood
D010770:Phosphotransferases; D006593:Hexokinase; D025481:Phosphofructokinase-2; D010732:Phosphofructokinase-1; D011770:Pyruvate Kinase