The Effect of Streptomycin on the Metabolism of Benzoic Acid by Certain Mycobacteria

Abstract

Streptomycin in concs. of 5-50 [gamma]/ml. inhibits oxidation of benzoic acid by a number of non-pathogenic mycobacteria. Strep-tamine and streptidine do not show this effect even at 500 [gamma]/ ml. The oxidation of trehalose, mannitol and certain other substances is less sensitive to streptomycin. When the organisms are grown in increasing concs. of streptomycin, the oxidation of benzoate by suspensions of the organisms becomes correspondingly less sensitive to inhibition by streptomycin. When the organisms are grown on benzoate-containing media, benzoic acid oxidation by cell suspensions becomes more resistant to inhibition by streptomycin. Benzoic acid and salicylic acid stimulate the O2 uptake of pathogenic mycobacteria (H37RV) but these compounds are not oxidized. Streptomycin does not inhibit this effect.