Fig. 1. Energy consumption per cell of Dictyostelium discoideum Ax-2 during a doubling time in the growing phase. The line at T = 27.5 °C indicates the upper temperature limit of this organism.
Thermal dissipation of the cellular slime mold, Dictyostelium discoideum Ax-2 in the growing phase was measured at various temperatures. Minimum energy consumption (Pτ D) was observed in the vicinity of the optimum temperature, T = 22−25 °C, where the doubling time (τ D) of the thermal dissipation rate (P) was shortest. On the other hand, P showed a maximum at T = 25 °C, close to the upper temperature limit of this organism, T = 27.5 °C. It is suggested that a conflict between the cell and mitochondria results in reduction of the activity of mitochondria at the upper temperature limit.
Fig. 1. Energy consumption per cell of Dictyostelium discoideum Ax-2 during a doubling time in the growing phase. The line at T = 27.5 °C indicates the upper temperature limit of this organism.
Fig. 2. Thermal dissipation rate per cell of Dictyostelium discoideum Ax-2. Triangles show those soon after temperature jumps from the optimum temperature.