Hospital Pathogen Found Capable of Degrading Medical Plastics, Raising Safety Concerns

Researchers at Brunel University London have discovered that Pseudomonas aeruginosa, a common hospital pathogen, can degrade polycaprolactone (PCL), a biodegradable plastic widely used in medical devices such as sutures, implants, and wound dressings. Published in the journal Cell Reports, the study is the first to confirm that a clinically relevant bacterium can break down medical-grade plastic, potentially compromising the safety of healthcare equipment.

Previously, plastic-degrading abilities were known only in environmental microbes. The team identified an enzyme named Pap1 in P. aeruginosa that effectively degrades PCL. When the gene encoding Pap1 was introduced into E. coli, the bacteria gained the ability to degrade PCL-based agar and microbeads. In contrast, P. aeruginosa lost this ability when the gene was knocked out.

Further analysis revealed that the presence of plastic promotes bacterial biofilm formation, increasing antibiotic resistance. Experiments using wax moth larvae showed that P. aeruginosa became significantly more virulent when PCL implants were present.

The findings highlight new concerns about ESKAPEE pathogens (including Enterococcus faecium, Staphylococcus aureus, and others) in clinical settings. Experts warn that their dual capacity for drug resistance and plastic degradation could enhance their persistence in medical environments and interfere with device functionality. The research team is now developing screening tools to detect plastic-degrading traits in other pathogens.