Estimated Drainage of Carbon from the Tricarboxylic Acid Cycle for Protein Synthesis in Suspension Cultures of Paul's Scarlet Rose Cells

The amount of carbon (μmoles of carbon atoms) drained from the tricarboxylic acid cycle for protein synthesis was compared with μmoles of CO₂ released from the cycle at 2-day intervals during the growth of suspension cultures of Paul's Scarlet rose. We concluded that during the period of most rapid protein synthesis (day 0-4) one-sixth as much carbon was drained from the tricarboxylic acid cycle for protein synthesis as was released as CO₂. By day 8, one-thirtieth of the amount of carbon released as CO₂ was incorporated into protein. Net protein synthesis stopped on day 8, but the evolution of CO₂/culture continued at its maximum rate until day 10.