Deltamycins, new macrolide antibiotics. I. Producing organism and fermentation

A streptomycete strain, P3409, which produced new basic macrolide antibiotics, deltamycins A1, A2 and A3 and carbomycin A (deltamycin A4) was considered to be a new subspecies for which the name Streptomyces halstedii subsp. deltae was proposed. Deltamycins A1, A2, A3 and A4 which were active against Gram-positive bacteria were produced in organic complex media.