Chloroplast Mutagenesis: Effect of N-Methyl-N′-Nitro-N-Nitrosoguanidine and Some Other Agents on Euglena

Treatment of normal green Euglena gracilis with N-methyl-N'-nitro-N-nitrosoguanidine results in permanent loss of the ability to form chloroplasts in close to 100 percent of the organisms. The resulting "bleached" strains can be maintained for over 100 generations; no reversion to chloroplast-containing organisms occurs within this time. Alkylating agents, azaserine, mitomycin C, acridines, nitrous acid, hydroxylamine, and gamma-irradiation do …