Original articles
Protomycin, A New Antibiotic of Cycloheximide Group. I
1963 年 16 巻 3 号 p. 111-114
詳細
1963 年 16 巻 3 号 p. 111-114
Protomycin, a new antibiotic active against Endameba histolytica as well as yeast, was isolated from culture filtrate of a strain of Streptomyces (Isolation No. S-300) in the screening program, in which Endameba histolytica was employed as a test organism. The antibiotic was purified to give a pale yellow viscous liquid with a homogeneity proved by a counter-current distribution technique. While the physicochemical and biological properties of protomycin suggest to be an antibiotic of cycloheximide series, it was differentiated clearly from the known antibiotics in that series. The in vivo effect of the antibiotic on E. histolytica was proved in guinea pigs and described previously1). In the present report, the protomycin-producing strain was characterized according to the established manner for streptomyces and described.
The strain No. S-300 produced a brown pigment in the protein-nitrogen containing media at the time of isolation, but gradually lost this ability during maintenance and improvement of the strain and changed into variants, which were classified into two groups on the basis of growth findings: One group grew into thick colonies with deep folds on nutrient agar as observed in the original strain; the other group remained to be a minute colony with a 2～3 mm diameter. Accordingly, in this report, the protomycin producing strains were classified into three types.
Type I: The original strain, producing pigment in the media containing organic nitrogen sources.
Type II: A variant which have lost the ability of pigment production and grows to large colonies.
Type III: Another variant which have lost the ability of pigment production and grows only to minute colonies.
