A study published on the website of Nature on May 8th claimed that a common pathogenic bacterium in hospitals, Pseudomonas aeruginosa, can produce a special enzyme that breaks down medical plastics. This discovery provides new clues to explain the tenacious survival ability of the pathogen in hospital environments, and also sounds the alarm for medical device safety. A research team from Brunel University in the UK found that Pap1 enzyme secreted by Pseudomonas aeruginosa can effectively degrade polycaprolactone (PCL) in patient wound isolates. This type of plastic is biodegradable and therefore widely used in medical devices such as sutures, implants, stents, or wound dressings. Scientists have only found similar abilities in environmental bacteria in the past, but now this characteristic has also been confirmed in pathogenic bacteria, perhaps revealing the "secret weapon" of the persistent existence of hospital pathogens. Through genetic engineering experiments, the team implanted the gene encoding the enzyme into Escherichia coli and observed the decomposition of PCL droplets. However, mutant strains that knock out this gene completely lose their ability to degrade plastics. What is even more worrying is that when exposed to plastic, the biofilm formation of this strain significantly increases, and this protective matrix is one of the culprits leading to increased antibiotic resistance. Stephen Jorjevic, a pathogen expert at the University of Technology Sydney, commented that as a member of the ESKAPE resistant bacterial community (including six "superbugs" such as Staphylococcus aureus and resistant Enterococcus), the new ability of Pseudomonas aeruginosa suggests that other resistant pathogens may also have the potential to degrade plastics. This discovery not only provides new ideas for hospital infection prevention and control, but also puts forward higher requirements for the future research and development of medical device materials. (New Society)