Uptake of (methyl-14C)-sisomicin and (methyl-14C)-gentamicin into bacterial cells.

Abstract

Eight sensitive strains (2 Staphylococcus aureus, 2 Escherichia coli, 2 Pseudomonas aeruginosa and 2 Klebsiella pneumoniae) and 4 resistant P. aeruginosa strains were used to study uptake of sisomicin and gentamicin by the bacterial cells. In 11 out of the 12 organisms studied employing (methyl-14C)-sisomicin and (methyl-14C)-gentamicin, uptake of the former was higher than that of the latter. In 1 organism, the uptake of the 2 antibiotics was similar. This higher uptake of sisomicin may help explain the superior potency of the antibiotic in relation to getamicin.