Effects of tetramethylthiuram disulphide (thiram) on adenine nucleotide (ATP, ADP, AMP) levels in the ciliate Tetrahymena pyriformis

Axenic cultures of Tetrahymena pyriformis GL populations were exposed to 0. 40 mu g/mL of tetra methylthiuram disulphide (TMTD). Doubling times and ATP , ADP and AMP levels were followed on control and treated populations at va rious cell densities during the exponential growth phase. For the control p opulations, the average generation time was 171.9 min and ATP levels were 2 -8 x 10(-14) mol/cell. For the treated populations, growth was reduced and the populations with the highest densities were more sensitive than populat ions treated with TMTD at the early stage of the exponential growth phase. For treated populations, ATP and ADP concentrations showed significant diff erences compared to the control populations. Mechanisms compensating the ac tion of the TMTD have been observed with treated populations at 25,000 cell s/mL density. Unfortunately AMP levels were unstable within control populat ions showing no differences with those from treated populations. (C) 1999 b y John Wiley & Sons, Inc.