Biological Studies on Mikamycin. III Influence of Blood on the Activity and Further Investigations on the Activity Against Experimental Infections

Abstract

Mikamycin belongs to the group of PA 114, streptogramin, staphylomycin and ostreogrycin. It is successfully applied for clinical uses. It is highly effective against gram-positive organisms in vivo as well as in vitro, in spite of the low levels in blood and tissues observed by antimicrobial activity.^1,2,3) The samples obtained before establishment of differential assay⁴⁾ of A and B were not well characterized and showed lower potency particularly in vivo than those obtained later.²⁾ These results bothered us and led us to further biological investigations of mikamycin. Influence of blood on activity of mikamycin, the activity observed by slide cell culture method and mouse protection tests against experimental infections by oral administration were investigated and the results are presented in this paper.