β-Lactamase inhibitory activities and synergistic effects of 5,6-cis-carbapenem antibiotics

Abstract

Twelve 5,6-cis-carbapenem antibiotics were examined for their β-lactamase inhibitory activities, their types of inhibitions, and their synergistic activities with otherβ-lactam antibiotics. All the carbapenems inhibited eight types of β-lactamases including cephalosporinases which were insensitive to clavulanic acid and sulbactam. The sulfonyloxy ethyl carbapenems were the most active inhibitors; they inhibited allβ-lactamases in a progressive fashion, whereas some of the hydroxyl compounds exerted non-progressive inhibition against severalβ-lact-amases such as those of Escherichia coli TN713 and Proteus vulgaris GN4413. Several carbapenems were inactivated by the β-lactamases of Citrobacter freundii GN1706, P. vulgaris GN4413, E. coli TN713, and Klebsiella pneumoniae TNI 698. Most of the carbapenems potentiated the antibacterial activities of ampicillin and cefotiam against β-lactamase-producing bacteria. © 1982, JAPAN ANTIBIOTICS RESEARCH ASSOCIATION. All rights reserved.