The influence of light and different ATP concentrations on cell aggregation in cyclic AMP sensitive and insensitive species of the cellular slime molds.

The influence of light and different concentrations of ATP on cell aggregation in cyclic AMP sensitive (Dictyostelium mucoroides, D. purpureum) and cyclic AMP insensitive species (Polysphondylium violaceum, P. pallidum, D. lacteum) of the cellular slime molds was observed in small and in large amoebal populations. Both light and ATP (optimal concentration: 10(-5) M) accelerated cell aggregation and increased the number of aggregating centers in large populations. For cyclic AMP sensitive species the effect of ATP in large populations was more pronounced than for the species that do not react to cyclic AMP. A possible explanation for the similar effect of light and ATP has been discussed.