The estimation of turnover of spermidine in Anacystis nidulans

Abstract

The turnover of spermidine in Anacystis nidulans was studied using [2-14C]methionine to prelabel intracellular spermidine. It was found that there is essentially neither excretion nor degradation of spermidine in exponentially growing Anacystis nidulans. Spermidine was degraded rapidly in stationary phase cells. The half-life of specific activity of spermidine in exponential phase was 8.3 h, a period similar to that of the doubling time (7.5 h) of the bacterium. The rate of synthesis of spermidine was calculated to be 0.04 nmol/108 cells/h.