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Updated: Aug 13, 2026
08:19
Generating Transposon Insertion Libraries in Gram-Negative Bacteria for High-Throughput Sequencing
Published on: July 7, 2020
[Beta-lactamases of Gram negative bacteria: never-ending clockwork!]
1Service de bactériologie, CHU Cochin, AP-HP, Paris. alain.philippon@cch.ap-hop-paris
Annales De Biologie Clinique
|January 20, 2006
Summary
Acquired resistance to beta-lactam antibiotics is increasing due to novel beta-lactamase enzymes. Molecular approaches are crucial for identifying resistance mechanisms and controlling antibiotic use.
Area of Science:
- Microbiology
- Molecular Biology
- Biochemistry
Context:
- Rising acquired resistance to broad-spectrum beta-lactams like third-generation cephalosporins (3GC) and carbapenems.
- Plasmid-encoded beta-lactamases are a major mechanism of resistance, with diverse enzyme classes identified.
Purpose:
- To review the mechanisms of acquired resistance to beta-lactam antibiotics.
- To highlight the emergence of various beta-lactamase enzymes conferring resistance.
- To emphasize the need for molecular identification and strict antibiotic control.
Summary:
- Resistance to 3GC involves mutated TEM/SHV enzymes and emerging ESBLs (e.g., CTX-M).
- Broader resistance, including to cephamycins and inhibitors, is linked to transferable cephalosporinases (class C) from various Enterobacteriaceae.
- Carbapenem resistance arises from novel enzymes (classes B, D, A) like IMP, VIM, KPC, notably in Salmonella.
Impact:
- Molecular methods are essential for detecting these enzymatic resistance mechanisms.
- The absence of new drugs necessitates strict control of beta-lactam antibiotics across medical, veterinary, and agricultural sectors.
- Emerging resistance poses a significant threat to public health, requiring global surveillance and intervention.
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