[Actinomyces chromogenes var. graecus var. nov., a producer of a new hexaene antibiotic].

Actinomycete LIA-O832 was isolated from a soil sample of Greece. By its antimicrobial spectrum, morphological and cultural properties the actinomycete was most close to Act. chromogenes but differed from the latter by the antibiotic and physiological properties. The actinomycete was classified as Actinomyces chromogenes var. nov. The culture produced an antibiotic complex including 4 antibiotics, i.e. a tetraen antibiotic primaricin, a new hexaen named grecomycim and 2 non-polyenic antibiotics, one of which was close to kikumycin and the other was close to aksenomycin. The physico-chemical characteristics of the antibiotics are presented.