1959 Volume 12 Issue 6 Pages 290-297
In the previous papers, mikamycin was reported to be apparently a single antibiotic, and the biological activities were studied with a crude material1–3). However improvements of the cultural conditions and further chemical studies revealed that mikamycin is composed of a few biologically active substances. A couple of them were isolated and purified by means of repeated chromatography, continuous extraction with ether, and recrystalization. The main component was designated mikamycin A and the second one mikamycin B14) These two antibiotics, produced by a single organism, were observed to exhibit a marked synergistic actions both in vitro and in vivo. Mikamycin is closely related to, if not identical with, PA 1144,5), streptogramin6,7), staphylomycin8–11) or E 12912,13). In the present publication some of biological studies of these two constituents of mikamycin will be reported, with particular reference to the synergism between them.