Abstract: | SYNOPSIS. Amoeboid Naegleria gruberi grown on an agar surface were induced to transform synchronously into flagellates by changing the pH of the environment from 3.8 to 7.2. Flagellates started to appear 70 min after stimulation, reached the 90% level within the next 30–40 min, and gradually reverted to the amoeboid form in the next several hrs. The presence of previously induced cells did not influence normal induction of transformation, indicating that no interaction took place during transformation. Inhibitors of oxidative phosphorylation (DNP and cyanide), of protein synthesis (puromycin and cycloheximide), and of RNA synthesis (actinomycin D), delayed or blocked the transformation, suggesting that RNA and protein synthesis are required. Because the flagellated stage is shortened by puromycin treatment, protein synthesis appears to be linked to the duration of the flagellated stage. |