The Physiological Youth of a Bacterial Culture as Evidenced by Cell Metabolism

Abstract

Bacteria grown in a continuously aerated medium show a burst of metabolic activity at the close of the lag period and beginning of the phase of logarithmic increase. This is manifest by a sharp rise in production of CO2 and NH3 per cell per hr. The authors show, however, that a considerable part of this increase is due to increased size of individual cells at this period. It is believed, however, that allowance for the factor of cell size, while it might wipe out differences between early and late phases of logarithmic increase, can not account for the excess activity in this period as a whole, as compared with subsequent phases of stable population.