The preparation and some properties of purified micrococcin

Abstract

The antibiotic micro-coccin, extracted by Su (1948) from Micrococcus sp. (N.C.T.C. no. 6571) was crystallized. The mother liquor contained another antibiotic closely similar to micrococcin. Micrococcin is almost insoluble in water. In ethanol-water mixtures its solubility rises to > 150 mg./ml. at 70-80% ethanol, then falls to less than 10 mg./ml. in absolute ethanol. It decomposes at 21 222-228[degree]. [a] = + 116[degree]. It has a broad absorption in the u.-v.'' D and many bands in the infrared. An ethanolic soln. has a strong purple fluorescence in near-visible u.-v. light. Both fluorescence and u.-v. absorption are reduced by traces of Cu and partly restored by BAL. The mol. wt. appears to be somewhat over 2000, and elementary analysis gave C, 49-49.5; H, 4.6; N, 13.9; S, 15.9%. It gives a positive ninhydrin reaction only after acid hydrolysis, but this seems to be due to ammonia, not amino-acids. Nothing is known of its chem. nature.