Ribo- and deoxyribonucleotide triphosphate pools in synchronized populations of Tetrahymena pyriformis.

The content of ribo- and deoxyribonucleotide triphosphates has been measured in asynchronous and synchronized populations of Tetrahymena pyriformis. The concentration of ribonucleotide triphosphates does not vary through the cell cycle. It seems to be a rule that the ATP pool is reduced during division only in cell types which also reduce macromolecular syntheses and respiration. The content of deoxyribonucleotide triphosphates varies through the cell cycle. The pools are maximal during the S-period, but measurable amounts are present in all phases.