CONTROL OF REDUCED DIPHOSPHOPYRIDINE NUCLEOTIDE OSCILLATIONS IN BEEF HEART EXTRACTS .2. OSCILLATIONS OF GLYCOLYTIC INTERMEDIATES AND ADENINE NUCLEOTIDES

Analysis of samples obtained during the course of DPNH oscillations on cell-free extracts prepared from beef heart have shown clear phase shifts between the changes in the reduced nucleotide and those occurring in the concentrations of other intermediates. The concentration of fructose 1,6-diphosphate (FDP) reached a maximum before the maximum in DPNH was attained and appeared 180 ° out of phase with respect to glucose 6-phosphate and fructose 6-phosphate. On the other hand, the concentration of dihydroxyacetone phosphate reached its maximum after the maximum in DPNH. Adenosine 5′-monophosphate and -diphosphate showed kinetics similar to those of FDP, and ATP appeared 180 ° out of phase with respect to the other adcnine nucleotides. This evidence supports the role of phosphofructokinase as the primary oscillator in this system, under the control of the adenine nucleotides. © 1968.