Book

Description

To study the interactions between the plasma membrane potential and metabolism, we analysed data recorded in yeast cells in suspension. The measurements include the energy state of the cell evaluated from the intracellular level of ATP in the yeast population, and the mitochondrial membrane potential obtained by a fluorescent recording. In addition, nicotinamide adenine dinucleotide NAD and hydrogen H substance (NADH), plays a role in the chemical process that generates energy for the cell, as well as the intracellular pH were measured. All measured parameters were oscillating over time under aerobic/anaerobic shift. The results were analysed using time series analysis methods that allow for time localised analyses of the underlying dynamics. We present results of analysis of interaction between cellular functional processes and argue that the metabolism is driving them. The results suggest that the mitochondrial F0F1-ATPase might be involved in the mechanism by which glycolytic oscillations are driving the oscillations in the mitochondrial membrane potential and the cytosolic pH. The results were modelled as phase oscillators of glycolysis, cytosolic pH and the mitochondrial membrane potential. This model regenerates the signals measured from yeast cells and show approximately the same main mode frequency as the original data.