Medical plastic-eating 'superbug' discovered
In a groundbreaking discovery, researchers have found that the bacterium Pseudomonas aeruginosa can degrade certain types of medical plastics, such as polycaprolactone (PCL), by producing an enzyme called Pap1. This revelation challenges the long-held belief that pathogens cannot degrade medical plastics and has significant implications for hospital-acquired infections.
P. aeruginosa is among a group of bacteria responsible for the majority of hospital infections that are resistant to antibiotics. The bacterium's ability to degrade plastics enables it to persist on medical devices that were previously considered inert and "sterile," effectively turning these materials into reservoirs of infection.
The degradation process helps P. aeruginosa to form stronger biofilms—communities of bacteria embedded in a protective matrix—that are more resistant to antibiotics and the host immune system. This makes treatment more difficult in hospital settings, particularly for vulnerable patients in intensive care units.
The enzymes similar to Pap1 have been identified in other hospital pathogens, suggesting a wider potential for biodegradation of various plastics used clinically. If left unchecked, this could broaden the infection risk beyond PCL to plastics like polyurethane or polyethylene terephthalate.
This discovery calls for reconsideration of device design, hospital sterilization protocols, and infection control strategies. Researchers suggest focusing on plastics harder for microbes to digest as a potential solution.
The implications of this discovery extend beyond one material, as other plastics could also be vulnerable to microbial attack. Infection control experts may need to reconsider how they monitor hospital environments.
A study led by Professor Ronan McCarthy at Brunel University of London showed that P. aeruginosa can use plastic as a carbon source and degrade it. The enzyme Pap1, isolated from the bacterium, degraded 78% of a plastic sample in just seven days.
Pseudomonas aeruginosa is listed on the World Health Organisation's critical priority list for new treatments and is a major cause of catheter-related Urinary Tract Infections and ventilator-associated pneumonia. The plastic-digesting ability of the bacterium could impact patient safety in modern medicine, particularly in the use of medical devices such as bone scaffolds, dental implants, catheters, and breast implants.
More research is urgently needed to understand the prevalence of these enzymes among pathogens and their impacts on virulence. The discovery highlights the need to understand the impact of microbial plastic degradation on modern medicine and to develop strategies to mitigate the risks associated with this phenomenon.
Digital health experts should closely monitor the impact of microbial plastic degradation on medical devices, as this could increase the risk of infection in vulnerable patients. The science behind this phenomenon may require a reevaluation of health-and-wellness strategies for maintaining sterility in hospitals, particularly for devices like bone scaffolds, dental implants, catheters, and breast implants.
