2‐Mercaptoethylamine, a competitive inhibitor of spermidine synthase in mammalian cells

Abstract
Spermidine synthase from rat ventral prostate was inhibited by 2‐mercaptoethylamine (MEA). Inhibition of spermidine synthase by MEA was competitive with respect to one of the substrates putrescine, but not competitive with respect to the other substrate decarboxylated S‐adenosylmethionine. MEA markedly depressed spermidine and spermine contents in human erythroid leukemia K562 cells, suggesting that these changes resulted from the inhibitory effect of MEA on spermidine synthase in situ.