Clavulanic acid inhibition of beta-lactamase I from Bacillus cereus 569/H.

Inactivation of beta-lactamase I by clavulanic acid was investigated. Clavulanic acid induced inhibition of the enzyme was found to be progressive with time. Benzylpenicillin provided protection against the adverse effects of the inhibitor initially, however, the enzyme was irreversibly inhibited in a progressive manner even in the presence of substrate. Reaction of beta-lactamase I with clavulanic acid, in the presence of ampicillin, led to a very rapid inactivation of the enzyme.