FIG 1.
Heterologous expression of DdlF258Y increases vancomycin sensitivity. (A) Plasmid expression of DdlF258Y in L. reuteri 6475 blocked growth in medium containing at least 300 μg/ml vancomycin, whereas growth of wild-type L. reuteri or L. reuteri harboring the control plasmid pVPL2042 was not inhibited in medium containing up to 500 μg/ml vancomycin. Data shown are representative of results from three biological replicates. The differences between replicates in the recorded MICs were no greater than 100 μg/ml. (B) L. reuteri bacteria containing pVPL2042 (left) and pVPL3862 (right) were replica plated from vancomycin to erythromycin plates, with results demonstrating that the presence of DdlF258Yreuteri provides selection in the presence of vancomycin.