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Updated: Jul 8, 2026
08:06
The Use of a β-lactamase-based Conductimetric Biosensor Assay to Detect Biomolecular Interactions
Published on: February 1, 2018
Extended-spectrum beta-lactamases: structure and kinetic mechanism
1Basilea Pharmaceutica Ltd, Basel, Switzerland. malcolm.page@basilea.com
Summary
The number of extended-spectrum beta-lactamases (ESBLs) has rapidly increased. This study discusses kinetic parameters for beta-lactam hydrolysis by ESBLs, considering their enzyme structures.
Area of Science:
- Biochemistry
- Microbiology
- Enzymology
Background:
- Extended-spectrum beta-lactamases (ESBLs) are enzymes conferring bacterial resistance to beta-lactam antibiotics.
- Class A ESBLs have shown a significant increase in prevalence and diversity in recent years.
Purpose of the Study:
- To analyze the steady-state kinetic parameters of beta-lactam hydrolysis by ESBLs.
- To correlate kinetic data with the structural characteristics of these mutant enzymes.
Main Methods:
- Review of existing literature on ESBL kinetics and structures.
- Analysis of steady-state kinetic parameters (e.g., kcat, Km) for various beta-lactams.
- Comparison of kinetic data with known three-dimensional structures of class A ESBLs.
Main Results:
- ESBLs exhibit diverse kinetic profiles for different beta-lactam substrates.
- Specific structural features, such as alterations in the active site, are linked to altered kinetic parameters.
- Mutant enzymes often display enhanced hydrolysis rates for certain antibiotics.
Conclusions:
- Understanding the structure-function relationship of ESBLs is crucial for predicting and combating antibiotic resistance.
- Kinetic parameters provide valuable insights into the catalytic mechanisms and substrate specificities of these enzymes.
- This knowledge can inform the development of new beta-lactamase inhibitors or alternative therapeutic strategies.
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