[Role of plasmid genes in neomycin synthesis]

Comparative investigation of the neomycin-producing strain and a strain which has spontaneously lost the capacity for the antibiotic synthesis suggested participation of the plasmid with the molecular weight of 59 X 10(6) dalton in determination of the biosynthesis of neomycin and phosphotransferase inactivating the antibiotics. This plasmid factor is not eliminated under the effect of the sublethal concentrations of acridine orange and ethidium bromide.