β-Lactam Resistance Mechanisms in Gram-Negative Bacteria

Gram-negative bacteria employ a multifaceted arsenal to evade β-lactam antibiotics, which act by targeting penicillin-binding proteins (PBPs) involved in cell-wall synthesis. Central to resistance is the production of β-lactamases—enzymes that hydrolyse the characteristic β-lactam ring—ranging from narrow-spectrum penicillinases to extended-spectrum β-lactamases (ESBLs), AmpC cephalosporinases and carbapenemases. Alterations in outer-membrane porins reduce antibiotic influx, while upregulated efflux pumps expel drugs from the periplasmic space. Target modification through PBP mutations further diminishes drug binding. The genetic plasticity of Gram-negative species facilitates horizontal acquisition of resistance determinants on mobile elements, accelerating global dissemination. Clinically, these mechanisms converge to compromise first-line agents such as penicillins, cephalosporins, monobactams and carbapenems, posing a growing public-health threat that demands rapid diagnostics, robust surveillance and novel therapeutic strategies.

Research from Nature Portfolio

Recent studies have introduced a paper-based visual sensor capable of discriminating subtypes of β-lactamases directly from clinical specimens within a few hours. This platform achieves complete sensitivity and specificity across diverse bacterial isolates and significantly enhances precision in antibiotic selection. By differentiating major β-lactamase families at the point of care, the sensor guides targeted therapy, reducing empirical misuse and improving clinical outcomes in both hospital and community settings. Its low cost, rapid turnaround and ease of use render it a promising tool for decentralised antimicrobial stewardship.

β-Lactam Resistance Mechanisms in Gram-Negative Bacteria publication trend

The graph below shows the total number of articles in β-lactam resistance mechanisms in gram-negative bacteria across all publications each year (not limited to Nature Index journals).

Technical terms

β-lactamase: Enzyme that hydrolyses the β-lactam ring of antibiotics, rendering them inactive.

Carbapenemase: Subclass of β-lactamase capable of degrading carbapenem antibiotics.

Extended-spectrum β-lactamase (ESBL): Enzyme that hydrolyses extended-spectrum cephalosporins and monobactams.

Porin: Outer-membrane channel protein that mediates uptake of small molecules, including antibiotics.

Efflux pump: Membrane transporter that actively expels antibiotics from the bacterial cell.

Point-of-care (POC) testing: Diagnostic assays performed at the site and time of patient care for immediate results.

References

1. Rapid and visual identification of β-lactamase subtypes for precision antibiotic therapy. Nature Communications (2024).
2. Highly Sensitive In Vivo Imaging of Bacterial Infections with a Hydrophilicity‐Switching, Self‐Immobilizing, Near‐Infrared Fluorogenic β‐Lactamase Probe Enriched within Bacteria. Advanced Science (2024).
3. Keeping up with the pathogens: improved antimicrobial resistance detection and prediction from Pseudomonas aeruginosa genomes. Genome Medicine (2024).