Lactamase Inactivation
نویسندگان
چکیده
A novel carbapenem, SF2103A, is a strong inhibitor of various types of 3-lactamase. Equimolar concentrations of SF2103A completely inactivated the cephalosporinases of Proteus vulgaris and Citrobacter freundii and type lb and type II penicillinases mediated by R plasmids in a progressive manner. The inactivation of the two penicillinases and P. vulgaris cephalosporinase was apparently irreversible; however, when the inactivated enzymes were separated from excess SF2103A by gel filtration, they showed very slow reactivation. The hydrolysis of SF2103A by these three 1-lactamases was below the limit of detection. It is concluded that SF2103A acts as a tight-binding competitive inhibitor for the penicillinases and P. vulgaris cephalosporinase. In contrast, the inactivation of C. freundii cephalosporinase by SF2103A
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