Comparison of the Antibacterial Activities of Sisomicin and Gentamicin Against Gram-Negative Bacteria

Sisomicin was found to be more active on a weight basis than gentamicin against Pseudomonas sp., Klebsiella sp., and indole-positive Proteus. Gentamicin was more active than sisomicin against Escherichia coli, Serratia sp., Enterobacter sp., and Proteus mirabilis. Both antibiotics were very active against methicillin-resistant strains of Staphylococcus aureus.