Figure 1.

Reduction of ofloxacin susceptibility conferred by plasmids pGEM-OFXr1 and pGEM-Rob_Yp. E. coli (Ec) and Y. pestis (Yp) strains were streaked on solid media without or with ofloxacin: 0.35 μg/ml (the concentration used in the screen) for E. coli and 0.15 μg/ml for Y. pestis. Ampicillin (100 μg/ml) was also added to the media for plasmid-carrying strains.