Gentamicins

Gentamicin is a new broad-spectrum antibiotic, basic and water-soluble, produced and developed by Schering Corporation-Bloomfield, New Jersey (1967 and 1968). It is produced by Micromonospora purpurea, a member of a genus of microorganisms from which no other antibiotics have been derived. Paper chromatographic techniques showed the components of gentamicin complex designated as C′, C′ a, and C₂. Gentamicins are bactericidal antibiotics, active in vivo in low concentrations against a wide spectrum of both Gram-positive and Gram-negative organisms. Among the responsive Gram-positive groups of microorganisms are Staphylococcus aureus including many resistant penicillinase producing strains and group A betahemolytic Streptococci. Among the clinically more important species of Gram-positive organisms responsive to gentamicin are both indolepositive and indole-negative Proteus, Pseudomonas, Escherichia coli, Aerobacter, Klebsiella, Salmonella, and Shigella.

The production of gentamicins was improved by adding cobalt to the growth medium.