腸チフス菌S,R型変異に関する研究 第三編 腸チフス菌のS型 → R型解離に及ぼす核酸の影響

Studies on the effect of unrefined Nucleic acid causing the variation of Typhoid dacillus turning to the rough type from the smooth type. In order to study such variation, subculture was made of Salmonellas 57 S and 58 S on nutrient agars adding the unrefined Nucleic acid at the rate of 10 γ/cc. The following is the brief summary of the results. 1) Culturing them on agar deeps every 20 days, the appearance of the rough type of Salmonellas 57 S and 58 S were seen till 7th and 5th culture on these media adding unrefined Nucleic acid extracted from Salmonella 57 S, and then on the agar deeps adding the one extracted from Salmonella typhi Nakagawai the appearance of the rough type of Salmonellas 57 S and 58 S were seen till 6th and 4th culture, and after that the rough type was not seen at all. 2) Culturing them on agar plates every 3 days, the appearance of the rough type of Salmonellas 57 S and 58 S were seen till 5th and 3rd culture on these media adding unrefined Nucleic acid extracted from Salmonella 57 S, and then on the media adding the one extracted from Salmonella typhi Nakagawai the appearance of the rough type of Salmonellas 57 S and 58 S were seen till 6th and 3rd culture, and after that the rough type was not seen at all.