a highly toxic broad-spectrum antibiotic mixture of related aminoglycoside substances derived from the actinomycete bacterium Micromonospora purpurea, used in its sulfate form in the treatment of severe Gram-negative infections.
a highly toxic aminoglycoside antibiotic, C 18 H 37 N 5 O 9 , derived from Streptomyces tenebarius, used in the treatment of serious infections due to susceptible Gram-positive and Gram-negative organisms.
