Oscillations of Respiration, Adenine Nucleotide Levels and Heat Evolution in Synchronous Cultures of Tetrahymena pyriformis ST Prepared by Continuous-flow Selection

Abstract

Respiration rates, adenine nucleotide levels and heat production were measured during exponential asynchronous growth of Tetrahymena pyriformis and in synchronous cultures prepared by continuous-flow selection. In synchronous cultures rates of oxygen uptake rose to maxima three times in each cell cycle. The ATP pool oscillated in phase with respiratory activity. The ADP and AMP pools oscillated in phase with each other, but out of phase with ATP, and the rate of heat production also showed fluctuations. Values calculated for adenylate energy charge were low, increasing from less than 0.2 to more than 0.4 during the mid-exponential phase of growth in an asynchronous culture, and oscillating over a range from 0.34 to 0.47 in a synchronous culture.