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Analysis of Yersinia enterocolitica Effector Translocation into Host Cells Using Beta-lactamase Effector Fusions
Published on: October 13, 2015
Characterization of beta-lactamase induction in Enterobacter cloacae
Antimicrobial Agents and Chemotherapy
|January 1, 1983
Summary
Beta-lactamase induction in Enterobacter cloacae depends on inducer stability. Unlike other systems, this induction is not affected by glucose or cyclic AMP, suggesting unique regulatory genes.
Area of Science:
- Microbiology
- Molecular Biology
- Biochemistry
Background:
- Beta-lactamase enzymes are crucial in bacterial resistance to antibiotics.
- Understanding the regulation of beta-lactamase induction is vital for developing new therapeutic strategies.
- Enterobacter cloacae is a significant opportunistic pathogen known for its antibiotic resistance mechanisms.
Purpose of the Study:
- To investigate the induction of beta-lactamase in a specific strain of Enterobacter cloacae.
- To determine the relationship between beta-lactam compound stability and the degree of enzyme induction.
- To elucidate the regulatory mechanisms governing beta-lactamase gene expression in this organism.
Main Methods:
- Exposure of Enterobacter cloacae to various beta-lactam compounds.
- Quantification of beta-lactamase activity.
- Kinetic analysis of the induction process.
- Assessment of the effects of glucose and cyclic AMP on induction.
Main Results:
- A broad range of beta-lactam compounds effectively induced beta-lactamase.
- The extent of induction correlated directly with the inducer's stability against enzymatic degradation.
- Induction kinetics suggested a repressor-controlled system with direct inducer-repressor interaction.
- Beta-lactamase induction was notably not subject to catabolite repression by glucose and was unaffected by exogenous cyclic AMP.
Conclusions:
- The regulation of beta-lactamase in this Enterobacter cloacae strain involves specific interactions between beta-lactam inducers and a repressor protein.
- The absence of catabolite repression and cyclic AMP influence indicates distinct regulatory gene organization compared to well-studied systems like the lactose operon.
- These findings highlight unique molecular mechanisms for antibiotic resistance gene expression in Enterobacter cloacae.
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