Contribution of cyclic adenosine 3':5'-monophosphate to the regulation of bacterial glycogen synthesis in vivo. Effect of carbon source and cyclic adenosine 3':5'-monophosphate on the quantitative relationship between the rate of glycogen synthesis and the cellular concentrations of glucose 6-phosphate and fructose 1,6-diphosphate in Escherichia coli.

When either fructose, glycerol, or succinate served as a sole source of carbon and energy in nitrogen-starved cultures of Escherichia coli W4597(K) the values of the kinetic constants of the equation that expresses the relationship between glycogen synthesis and hexose phosphates were different from the values observed when glucose was the sole source of carbon and energy. Addition of glucose during either exponential growth or nitrogen starvation to a culture using one of the other carbon sources slowed the rate of glycogen synthesis and shifted the values of the constants toward the values observed in cultures using glucose alone. Addition of cyclic AMP (cyclic adenosine 3':5'-monophosphate) during exponential growth of a culture using glucose caused the values of the constants to be shifted toward the values observed in cultures using a carbon source other than glucose. In all of the metabolic conditions studied in this report the adenylate energy charge ((ATP + 1/2 ADP)/(ATP + ADP + AMP)) and the level of the rate-limiting enzyme of glycogen synthesis, ADP-glucose synthetase (glucose 1-phosphate adenylyltransferase, EC 2.7.7.27), were the same. The data presented here indicate that the difference we observed in the quantitative relationship for glycogen synthesis is the result of the different cellular levels of cyclic AMP in the cells using glucose and the cells using one of the other carbon sources. Since cyclic AMP does not affect the velocity of ADP-glucose synthetase in vitro, apparently a change in the cellular level of cyclic AMP causes a shift in the cellular level of a presently unknown (and previously undetected) effector of this enzyme. The shift in the level of this effector evidently alters the response of the enzyme in vivo to the substrate glucose 1-phosphate and the activator fructose 1,6-diphosphate.

Evidence for the coordinate control of glycogen synthesis, glucose utilization, and glycolysis in Escherichia coli. I. Quantitative covariance of the rate of glucose utilization and the cellular level of fructose 1,6-diphosphate during exponential growth and nutrient limitation.

In cultures of Escherichia coli W4597(K) and G34 under various nutritional conditions the rates of glucose utilization and cellular levels of fructose-1,6-P2 are quantitatively related by the Hill equation where the value of the Hill coefficient is approximately equal to 2. This is the first evidence that fructose-P2, or any metabolite which covaries with fructose-P2, modulates glucose utilization in E. coli. In light of previous observations from our laboratory this new observation and those in the succeeding report provide the first evidence that in E. coli glycolysis, glycogen synthesis and glucose utilization are coordinately regulated, thus providing for the coupling of ATP utilization and production under various metabolic circumstances. Alterations in the level of ATP apparently affect the velocity of phosphofructokinase, the rate-limiting enzyme in glycolysis, altering the cellular levels of glucose-6-P or fructose-P2. Changes in the levels of these hexose phosphates are quantitatively related to alterations in the rates of glucose utilization and glycogen synthesis in the intact E. coli cell.

Evidence for the coordinate control of glycogen synthesis, glucose utilization, and glycolysis in Escherichia coli. II. Quantitative correlation of the inhibition of glycogen synthesis and the stimulation of glucose utilization by 2,4-dinitrophenol with the effects on the cellular levels of glucose 6-phosphate, fructose, 1,6-diphosphate, and total adenylates.

In cultures of Escherichia coli W4597(K) and G34 under various nutritional conditions the rates of glucose utilization and cellular levels of fructose-1,6-P2 are quantitatively related by the Hill equation where the value of the Hill coefficient is approximately equal to 2. This is the first evidence that fructose-P2, or any metabolite which covaries with fructose-P2, modulates glucose utilization in E. coli. In light of previous observations from our laboratory this new observation and those in the succeeding report provide the first evidence that in E. coli glycolsis, glycogen synthesis and glucose utilization are coordinately regulated, thus providing for the coupling of ATP utilization and production under various metabolic circumstances. Alterations in the level of ATP apparently affect the velocity of phosphofructokinase, the rate-limiting enzyme in glycolsis, altering the cellular levels of glucose-6-P or fructose-P2. Changes in the levels of these hexose phosphates are quantitatively related to alterations in the rates of glucose utilization and glycogen synthesis in the intact E. coli cell.