19/05/2026
๐ EFMC Literature Spotlight ๐
This editionโs contribution, provided by Dr Gwenaรซlle Jรฉzรฉquel (Laboratory of Coordination Chemistry, Toulouse, France), discusses the recently published article โBreaking Down Barriers: CorA Effectively Targets Staphylococcal Biofilms in Vitro and in Vivoโ by De Benedetti et al., published in ChemMedChem.
Antimicrobial resistance is often called โthe silent pandemicโ, as it represents a global burden causing an estimated 5 million deaths per year. This is a pressing matter that is addressed in this monthโs publication by targeting biofilms in Staphylococcus aureus. Biofilms are structured, surface-associated microbial communities embedded in a self-produced extracellular matrix that exhibit enhanced resistance to antibiotics and host immune responses. Current treatments for staphylococcal biofilms, often relying on rifampicin-based regimens, are limited by the rapid development of resistance, hepatotoxicity, and drug-drug interactions, while glycopeptides like dalbavancin struggle to pe*****te established biofilms.
The authors evaluated corallopyronin A (CorA), a natural product antibiotic produced by Corallococcus coralloides, for its potential to inhibit and eradicate staphylococcal biofilms. CorA targets the switch region of bacterial RNA polymerase, distinct from the rifampicin-binding site, conferring activity against rifampicin-resistant (Rif-R) strains while sparing eukaryotic polymerases. The study assessed CorAโs efficacy across a panel of clinical and reference S. aureus strains, including strong biofilm formers and Rif-R isolates, using Calgary biofilm device assays and confocal laser scanning microscopy. CorA prevented biofilm formation, but also eradicated established biofilms at concentrations close to its MIC, outperforming dalbavancin (4โ128ร MIC) and rifampicin (4โ8ร MIC). Notably, CorA retained activity against Rif-R strains, a critical advantage over existing therapies. Interestingly, it also reduced the viable population in established biofilms for 97% of the 33 strains tested.
In a murine foreign body infection model with S. aureus SA113, CorA treatment achieved a reduction in bacterial loads on implanted catheters and surrounding tissues, comparable to high-dose rifampicin (12.5 mg/kg). Additionally, CorA reduced local inflammation, as evidenced by lower edema sizes and decreased IL-1ฮฒ levels in peri-implant tissues. These results highlight CorAโs potential as a dual-action agent, effective against both planktonic and biofilm-embedded staphylococci, including resistant strains, while mitigating inflammatory responses.
This work positions CorA as a promising candidate for treating biofilm-associated infections, where conventional antibiotics often fail. Its unique mechanism of action, low resistance frequency, and favorable ADME properties further support its clinical potential.
๐ Read the full article here: https://buff.ly/KtyUFz0
