The contribution of common rpsL mutations in Escherichia coli to sensitivity to ribosome targeting antibiotics.

Point mutations in the rpsL gene encoding ribosomal protein S12 can generate resistance to streptomycin, resulting in rapid emergence of resistance to this antibiotic during treatment. In this work, we demonstrate that while spontaneous rpsL mutants in Escherichia coli are resistant to streptomycin, they are more sensitive to the ribosome – targeting antibiotics chloramphenicol, tetracycline and erythromycin. Moreover, combinations of these antibiotics, even in low concentrations were enough to achieve complete growth inhibition of both wild type and rpsL mutant strains. Thus, combining ribosome-targeting drugs can be used as a new treatment strategy that may be effective against streptomycin-resistant ribosome mutants.