Abstract
A mutant strain MS537-59 was isolated from Staphylococcus aureus MS537, in which leucomycin, in addition to erythromycin, was an active inducer for macrolide resistance. By pretreatment with subinhibitory concentrations of leucomycin, MS537-59 acquired a high resistance to both macrolide antibiotics as well as lincomycin. Erythromycin exhibited the highest activity as inducer followed by leucomycin. An acyl group on the mycarose and an aldehyde group were found to be needed for inducer activity by leucomycin.
