The lividomycins are new aminoglycosidic antibiotics containing 2-amino-2,3-dideoxy-D-glucose and are produced by Streptomyces lividus nov. sp., strain No. 2230-Nx. This antibiotic was previously reported as antibiotic No. 22302) or quintomycin3). However, owing to the similarity of the name quintomycin with the trade name "quintamycin", the name was changed to lividomycin. Lividomycins A and B have been isolated, purified and characterized. The lividomycins-producing strain also produces mannosyl paromomycin and paromomycin I. In the course of antibiotic screening studies, new antibiotics, the lividomycins were isolated from fermented broths of strain No. 2230-Nx. The morphological, cultural and physiological characteristics of strain No. 2230-Ni were studied and as a result of comparison with known species, the organism was considered a new species. This paper describes morphological, cultural and physiological characteristics of strain No. 2230-Ni. The fermentative production, isolation, purification, physicochemical properties and biological activities of the lividomycins are reported in the succeeding paper.