Sapurimycin, new antitumor antibiotic produced by Streptomyces. Producing organism, fermentation, isolation and biological properties.

In screening actinomycetes for antitumor compounds, Streptomyces sp. DO-116 was found to produce a new antitumor antibiotic sapurimycin. It is structurally related to, but distinct from, kapurimycins. The antibiotic was produced in a fermentation medium supplemented with high porous polymer resin which adsorbs antibiotic in the culture and results in an increase of titer. Active material was separated from the polymer resin by a solvent extraction procedure and isolated by repeated solvent extraction, adsorption chromatography and HPLC. Sapurimycin was active against bacteria, particularly Gram-positive organisms. It exhibited antitumor activity against leukemia P388 and sarcoma 180 in mice. Sapurimycin caused single strand breaks in supercoiled plasmid DNA in vitro. These results are discussed in comparison with data for kapurimycins.