A New Toxic Substance,Teleocidin, Produced by Streptomyces.

In the course of studies on the screening of specific toxic substances produced by Streptomyces against aquatic organisms, it was recognised that a newly isolated Streptmyces, 2A 1563, which was considered to be a variant species of Streptomyces mediocidicus produces a new toxic substance, Teleocidin. Teleocidin was isolated as a white powder resembling crystals with a crystal appearance from the methanol extracts of the cultured mycellium, and showed a specific toxic action toward Japanese killifish and mice, but did not exhibit any inhibition against microorganisms.