Objective:To study the inhibitory activity of sulbactam

clavulanic acid and tazobactam on the clinical bacterium which produces β-lactamase.Compare the inhibitory ways and inhibitory effects of three inhibitors.Methods:Study of inhibitory activity of these three β-lactamase on the 8 bacteria producing β-lactamase by spectrophotometry.Inhibition constant(K)iwere obtained from dixon plot and the relevance kinetic parameters of inhibition were calculated.Result:All inhibition modality of 3β-lactamase inhibitors are the competitive inhibition.Sulbactam is the weakest of the relative inhibitory effect of three inhibitors

and the strongest is tazobactam. Conclusion:There were differences between inhibitory effects of three enzyme inhibitors on different strains producing β-lactamase.