| Abstract: | Ornithine decarboxylase activity and polyamine levels were determined at various growth phases of Tetrahymena thermophila cultures. Enzyme activity and intracellular polyamines increased in exponentially growing cells and peaked just before the stationary phase. Putrescine was the predominant polyamine and spermidine and spermine concentrations were low throughout. The increase in putrescine level can be totally accounted for by the enzyme activity detected, provided that there is an ample supply of the precursor, L-ornithine. |
