THE INFLUENCE OF AGE ON ENZYMATIC ADAPTATION IN MICROORGANISMS

Abstract

The influence of age on enzymatic adaptation has been investigated with respect to the nitrate reductase and formic hydrogenlyase systems of Escherichia coli and the gluconate and benzoate oxidizing systems of Pseudomonas fluorescens. In all cases the adaptability steadily decreases during the period of active growth from the high level of the original inoculum and is restored as the cells enter the stationary period of growth. Lowered adaptability is evidenced by an increase in the lag period required for the development of max. activity in all cases, and by a lowered maximum activity in the case of formic hydrogenlyase adaptation. The latter adaptive system appears to be diluted out during growth and resynthesized as growth slows down. The preadaptive activity of nitrate reductase parallels the adaptability of this enzyme during growth.