FIG 2.

Antibiotic binding to wild-type and mutant recombinant PBP4. Recombinant PBP4 samples were incubated with 0 to 100 μg/ml (fluorescent gels on the left) and 0 to 2,000 μg/ml (percent densities in the graphs on the right) of ceftobiprole (BPR) (A), ceftaroline (CPT) (B), or nafcillin (NAF) (C) for 15 min at 37°C and then labeled with Bocillin-FL. Band density was measured with a Typhoon Trio variable-mode imager and analyzed with ImageQuant TL software. Percent density is relative to that for the no-antibiotic control (0 μg/ml). Data are representative of those from one of two independent experiments.