Open AccessCharacterization of beta-lactamase induction in Enterobacter cloacae
Author(s) -
Thomas D. Gootz,
Christine C. Sanders
Publication year - 1983
Publication title -
antimicrobial agents and chemotherapy
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.07
H-Index - 259
eISSN - 1070-6283
pISSN - 0066-4804
DOI - 10.1128/aac.23.1.91
Subject(s) - enterobacter cloacae , catabolite repression , repressor , lac repressor , operon , inducer , biology , microbiology and biotechnology , escherichia coli , lac operon , enzyme inducer , enterobacteriaceae , enterobacter , gene , biochemistry , enzyme , gene expression , mutant
The induction of beta-lactamase was studied in a strain of Enterobacter cloacae. A wide variety of beta-lactam compounds were found to induce beta-lactamase in this organism, and the degree of induction was directly related to the stability of the inducer to degradation by the enzyme. The kinetics of the induction process were consistent with a system normally under repressor control, suggesting a direct interaction of the beta-lactam compound with a repressor protein in the E. cloacae cells. Although these characteristics are common to many inducible systems in gram-negative organisms, the induction of beta-lactamase in this strain was not subject to catabolite repression with glucose and remained unaffected by exogenous cyclic AMP in the culture medium. This suggests that the organization and function of the beta-lactamase regulatory genes in E. cloacae are unlike those of other inducible gene systems, such as those composing the well-characterized lactose operon in Escherichia coli.