Abstract
Summary
Subtilin, an antibiotic extracted from Bacillus subtilis, was found to be antagonistic chiefly against Gram-positive organisms, including Mycobacterium tuberculosis and other acid-fast bacteria. Two notable exceptions were Neisseria catarrhalls and N. gonorrhoeae, both Gram-negative but also antagonized by subtilin. The antibiotic showed an extremely low toxicity for embryonic chick heart tissue fragments cultivated in vitro. Under the conditions of the test subtilin was approximately 20 times more toxic to Staphylococcus aureus than to chick heart tissue, a remarkably low tissue toxicity. A unit of subtilin is defined as the amount contained in 1 cc of the highest dilution capable of killing Staphylococcus aureus in 10 minutes at 37°C (F.D.A. phenol coefficient method).
Get full access to this article
View all access options for this article.