Analysis of the dynamics of relaxation type oscillation in glycolysis of yeast extracts

Abstract

In yeasts, the glycolysis may display oscillations of its metabolites while it is converting glucose. The dynamics of the oscillations has been investigated in cytoplasmic extracts of yeast under relaxation type conditions by determining the time course of some of the glycolytic metabolites. The compounds of the nucleotide pool have been identified as fast variables and the glucose derivatives as slow variables of the relaxation type. The period of oscillation has been subdivided into four phases which represent prominent parts of the limit cycle in the phase plane of a slow versus a fast variable. From the reaction processes in these phases, a dynamical picture of the mechanisms of oscillations is suggested. Accordingly, the oscillation results from an alternating activity of the fructose bisphosphate and the polysaccharide synthesis, both of which are coupled to glycolysis via the nucleotide pool. The processes in the phases are analyzed by calculating the rates of the reaction steps in the biochemical pathway.

Are Metabolic Oscillations Responsible for Normal Oscillatory Insulin Secretion?

“…Glycolytic oscillations have been studied extensively by us in skeletal muscle extracts (21)(22)(23)(24)(25)(26) and by others in yeast cells and extracts (27)(28)(29)(30)(31), heart extracts (32), and ascites tumor cells (33). An example of oscillatory glycolysis in a cellfree muscle extract is shown in Fig.…”

Oscillations in Oxygen Consumption by Permeabilized Clonal Pancreatic β-Cells (HIT) Incubated in an Oscillatory Glycolyzing Muscle Extract: Roles of Free Ca2+, Substrates, and the ATP/ADP Ratio

“…Ca 2+ oscillations have also been seen in single p-cells stimulated with glucose (5-7). We have suggested that these oscillatory phenomena may derive from oscillatory metabolism of glucose, such as has been demonstrated in extracts of skeletal muscle (8)(9)(10)(11)(12), heart (13), and yeast (14,15), as well as in intact yeast (16)(17)(18) and ascites cells (19). The mechanism of the oscillations in skeletal muscle extracts involves a rather unusual form of enzyme regulation in which the product activates the enzyme.…”

Modeling the synchronization of yeast respiratory oscillations

“…Glycolytic and respiratory oscillations are more amenable to theoretical analysis because the limit cycle dynamics are attributable to cellular metabolism and independent of cell cycle progression. A number of experimental (Das and Busse, 1991;Ghosh and Chance, 1964) and modeling (Bier et al, 2000; studies have attempted to decipher the metabolic determinants of glycolytic oscillations. These studies support the hypothesis that an autocatalytic reaction involving the glycolytic enzyme phosphofructokinase causes single cells oscillations.…”