Changes in Adenine Nucleotide Levels and Adenine Salvage During the Growth of Vinca rosea Cells in Suspension Culture)

Adenylate levels in Vinca rosea cells changed markedly during growth in a batch suspension culture. A ten-fold increase in ATP content expressed in moles per cell was observed in the lag phase (between 0 and 1 day)of the culture, although little increase in ADP and AMP contents was found in this phase. The incorporation rate of [8-'4C]adenine into the adenine nucleotide fraction of the cells and activity of adenine phosphoribosyltransferase (AMP: pyrophosphate phosphoribosyltransferase, EC 2.4.2.7)measured in the cell extracts also increased during the same phase of cell growth. The adenine nucleotide content decreased with cell division and increased again with cell expansion. The adenylate energy charge changed from 0.41 to 0.72 during the first day of culture and then decreased in the cell division phase. These results suggest that the adenylate metabolism of Vinca cells during the early stages of culture can be divided into two stages: an «energy-generating stage» during the initial lag phase of cell growth and an «energy-utilizing stage» which is initiated in the cell division phase. The rapid increase in ATP content during the lag phase of cell growth may be at least partially due to the activation of adenine salvage appearing in this phase.