FIG. 3.

Time course of the hydrolysis of various penems by the β-lactamase prepared from P. aeruginosa PAO1. The reaction mixture contained 0.5 μM β-lactamase and 10 μM penem in 50 mM sodium phosphate buffer (pH 7.0), and this was incubated for the indicated times. Each data point represents the level of residual antibacterial activity of the penem after incubation with β-lactamase for the indicated time.