ACETALDEHYDE MEDIATES THE SYNCHRONIZATION OF SUSTAINED GLYCOLYTIC OSCILLATIONS IN POPULATIONS OF YEAST-CELLS

In the presence of cyanide, populations of yeast cells can exhibit sus tained oscillations in the concentration of glycolytic metabolites, NA DH and ATP. This study attempts to answer the long-standing question o f whether and how oscillations of individual cells are synchronized. I t shows that mixing two cell populations that oscillate 180 degrees ou t of phase only transiently abolishes the macroscopic oscillation. Aft er a few minutes, NADH fluorescence of the mixed population resumes os cillations up to the original amplitude. At low cell densities, additi on of acetaldehyde causes transient oscillations. At higher cell densi ties, where the oscillations are autonomous, 70 mu M acetaldehyde caus es phase shifts. Extracellular acetaldehyde is shown to oscillate arou nd the 70 mu M level. We conclude that acetaldehyde synchronizes the o scillations of the individual cells.