A novel macromolecular antibiotic, SN-07. Taxonomy of producing organism, isolation, characterization and biological activities.

A novel macromolecular antibiotic SN-07 was obtained from the cultural supernatant of Actinomadura roseoviolacea var. miuraensis nov. var. The antibiotic was soluble in water, had a molecular weight of 18,000-22,000 daltons in 50 mM Tris-HCl buffer, pH 7.0, containing 2.0 M KCl as compared with authentic proteins. Its major constituents were nucleic acids. The substance had antibacterial activity against Gram-positive bacteria. It was also effective against lymphocytic leukemia P388 in vivo.