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The Use of a β-lactamase-based Conductimetric Biosensor Assay to Detect Biomolecular Interactions
Published on: February 1, 2018
TLA-2, a novel Ambler class A expanded-spectrum beta-lactamase
Delphine Girlich1, Laurent Poirel, Andreas Schlüter
1Service de Bactériologie-Virologie, Université Paris XI, Hôpital de Bicêtre, Assistance Publique/Hôpitaux de Paris, Faculté de Médecine Paris-Sud, Le Kremlin-Bicêtre, France.
Antimicrobial Agents and Chemotherapy
|October 28, 2005
Summary
A novel beta-lactamase, TLA-2, was identified on a plasmid from wastewater bacteria. This enzyme primarily breaks down cephalosporin antibiotics, posing a potential threat to antimicrobial resistance surveillance.
Area of Science:
- Microbiology
- Biochemistry
- Environmental Science
Background:
- Beta-lactamase enzymes are a significant mechanism of antibiotic resistance.
- Wastewater treatment plants can act as reservoirs for antibiotic-resistant bacteria and genes.
- The emergence of new beta-lactamases necessitates continuous monitoring and characterization.
Purpose of the Study:
- To identify and characterize a novel beta-lactamase, TLA-2, from a wastewater environment.
- To determine the enzymatic activity and substrate specificity of TLA-2.
- To understand the genetic context (plasmid) of TLA-2.
Main Methods:
- Isolation of bacterial strains from wastewater treatment plant samples.
- Plasmid DNA extraction and sequencing.
- Cloning and expression of the TLA-2 gene.
- Biochemical assays to determine enzyme activity and substrate hydrolysis profiles.
Main Results:
- Identification of a 47-kb plasmid encoding the TLA-2 beta-lactamase from an unidentified bacterial strain.
- TLA-2 is classified as an Ambler class A beta-lactamase.
- TLA-2 exhibits significant amino acid identity to known beta-lactamases CGA-1 and TLA-1.
- The enzyme demonstrates hydrolytic activity predominantly against cephalosporins.
Conclusions:
- TLA-2 represents a novel beta-lactamase with potential implications for cephalosporin resistance.
- The presence of TLA-2 in a wastewater environment highlights the role of such settings in the dissemination of antibiotic resistance genes.
- Further studies are warranted to assess the prevalence and clinical relevance of TLA-2.
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