Effect of Streptomycin on Acetobacter capsulatum and its Associated Dextran–Dextrinase Enzyme System

Abstract

IN an earlier publication¹, we have reported that Acetobacter capsulatum N.C.I.B.4943 failed to grow in a yeast extract – glucose medium containing 1 µgm. per ml. of streptomycin sulphate. More recently, we have found that A. capsulatum is sensitive to 1 µgm. per ml. of streptomycin sulphate at pH 4.5 and to 0.01 µgm. per ml. at pH 6.5 during 48 hr. incubation at 25° in the same medium. The effect of pH on antibiotic activity is already well recognized; but the extreme intolerance of A. capsulatum to streptomycin would seem to be unusual and worthy of note.