Polypeptide antibiotic 26a from Bacillus subtilis. IV. Evaluation of biological in vivo activity.

The studies performed with the antibiotic 26a, which has a close resemblance to bacitracin family polypeptide antibiotics, revealed a prominent therapeutic and protective actions. The antibiotic is characterized by a moderately low toxicity, lack of cytotoxic and cytostatic effects on several tissue cultures, and therapeutic effectiveness in lethal streptococcal infections in mice, and corynebacterial infections in guinea pigs.