Perturbation of enzyme activity in cells of the fission yeast schizosaccharomyces pombe subjected to continuous-flow centrifugation
Fluctuations in glutamine synthetase activity were observed when exponentially dividing cells of Schizosaccharomyces pombe were synchronized by continuous-flow centrifugation. These fluctuations were not seen in a control culture in which cells were allowed to grow asynchronously following filtration. However, when an asynchronous control culture was prepared by allowing cells to pass quickly through the continuous-action rotor without size selection, marked fluctuations in glutamine synthetase activity occurred. It is concluded that when the continuous-flow size selection method of cell synchronization is used, suitable control experiments are essential before any conclusions can be drawn about how enzyme synthesis is regulated during the cell cycle.