Thiol-Mediated Reduction of <i>Staphylococcus aureus</i> Tellurite Resistance

Abstract

The goal of this work was to enhance tellurite toxicity against Gram positive bacteria, especially Staphyloccocus aureus. Using a combination of assays (growth inhibition zones, growth curves, and minimal inhibitory concentrations), tellurite toxicity against this bacterium was tested in the presence of various SH- and OH-containing compounds. Results showed that the noxiousness of tellurite was strongly enhanced in the presence of 2-mercaptoethanol or dithiothreitol. The potentiating effect was observed in S. aureus ATCC 6538 (the model organism of this study) and in other Gram positive bacteria such as Bacillus subtillis ATCC 6051 and the methicillin-resistant S. aureus strain 622-4. No enhancing effect was observed in Gram negative bacteria such as Escherichia coli BW25113, Salmonella Typhimurium LT2 and Klebsiella pneumoniae ATCC 11388. These results open new perspectives for studying the treatment of multidrug-resistant Gram positive bacteria, which are responsible for numerous nosocomial infections.