Effect of enzyme concentrations on sustained oscillations in the fructose 6-phosphate/fructose 1,6-bisphosphate-cycle.
Sustained oscillations were investigated in an open and homogeneous enzyme system reconstituted from phosphofructokinase, fructose 1,6- biphosphatase , pyruvate kinase, adenylate kinase, and glucose 6-phosphate isomerase. The generation of oscillations if mainly due to antagonistic kinetic effects of AMP on phosphofructokinase and fructose 1,6- biphosphatase under the experimental conditions applied. Sustained oscillations were obtained in a broad range of maximum activities of phosphofructokinase or fructose 1,6- biphosphatase are increased. At low maximum activities of the two enzymes oscillations arise, which form a folded limit cycle, while by increasing concentrations of phosphofructokinase or fructose 1,6-bisphosphatase sustained oscillations are introduced, which are restricted to two dimensions.
D000263:Adenylate Kinase / Q000378:metabolism; D000818:Animals; D006597:Fructose-Bisphosphatase / Q000378:metabolism; D005635:Fructosediphosphates / Q000378:metabolism*; D005636:Fructosephosphates / Q000378:metabolism*; D005956:Glucose-6-Phosphate Isomerase / Q000378:metabolism; D006598:Hexosediphosphates / Q000378:metabolism*; D007700:Kinetics; D009991:Oscillometry; D010732:Phosphofructokinase-1 / Q000378:metabolism; D011770:Pyruvate Kinase / Q000378:metabolism
D005635:Fructosediphosphates; D005636:Fructosephosphates; D006598:Hexosediphosphates; C027618:fructose-6-phosphate; D010732:Phosphofructokinase-1; D011770:Pyruvate Kinase; D000263:Adenylate Kinase; D006597:Fructose-Bisphosphatase; D005956:Glucose-6-Phosphate Isomerase; C029063:fructose-1,6-diphosphate