[Effect of heavy water on the growth, glucose assimilation and stability of Escherichia coli to freezing-thawing].

Growth and resistance to freezing--thawing of Escherichia coli B-1640 were investigated during cultivation in synthetic media prepared with H2O and D2O. It is found that during cultivation in D2O the maximum specific growth rate decreases and the duration of the exponential growth phase increases. During the growth in D2O the glucose consumption rate drops in the exponential growth phase, the lactate content in the culture liquid is lower by two orders than that in H2O; the resistance to freezing--thawing is lower than that in H2O.

[Physiological properties of Saccharomyces cerevisiae during sine-modulated and stepwise changes in the medium pH].

The responses of a chemostat Saccharomyces cerevisiae culture (D = 0.1 h-1) to a stepwise increase or decrease in the pH of the medium were shown to be asymmetric. When the pH was lowered from 6.

[Analysis of distribution of S. cerevisiae cells for protein content using cell cycle models].

Histograms of cell distributions according to protein content obtained by means of flow cytofluorometry characterize the physiological state of the population as a whole and permit to calculate the velocity of protein accumulation in the cell in the course of the cell cycle. Dependence of population heterogeneity on culturing conditions is considered. Mathematical analysis of histograms of continuous cultures of S.

[Changes in the volutin levels in yeast cells during cell cycle].

Dimeric distribution of the cell number of Saccharomyces cerevisiae is analysed according to the volume and content of volutin in them. Dynamics of the age composition of the population in time when changing the medium limiting growth for the balanced one is considered. The data obtained indicate that volutin may serve as a regulator when the yeast cells pass the starting point in the division cycle, however, this event has no contrary effect on volutin accumulation.

[Relation of fluctuations in the physiological traits of a continuous Saccharomyces cerevisiae culture to the cell division cycle].

Such physiological characteristics of a continuous Saccharomyces cerevisiae culture as the rate of O2 uptake and CO2 evolution, the rate at which the medium was acidified, were found to vary. When the flow rate was increased from 0.05 to 0.

[Mechanism of growth limitations in a recombinant strain of Escherichia coli].

A recombinant Escherichia coli strain with the cloned gene of restriction endonuclease EcoR-V was studied. The diauxic growth of this strain under batch conditions, the composition of excreted products and the hyperbolic shape of the chemostat growth curve has made it possible to formulate the following hypothesis. At a high flow rate, one of the first reactions in the tricarboxylic acid cycle or a reaction directly preceding the cycle is a limiting step in the metabolism of E.

[Characteristics of the stoichiometric regulation of glycolysis in prokaryotic cells. A model].

A model is developed to investigate the steady state of the glycolytic system of procaryotic cells which have the hexose transport into the cell coupled with phosphoenolpyruvic acid-dependent phosphorylation. Analysis of the model shows that this phosphorylation results: 1) in stoichiometric connection between the rate of hexose consumption and the utilization of ATP and 2) the stoichiometric positive feedback. The latter can be the cause of bistability, oscillations and other nonlinear phenomena.