The Journal of the American Chemical Society has published a new study that suggests it may be possible to fight superbugs with conventional antibiotics. By pairing the drugs with a new class of metal-based agents called metallopolymers, which revitalize their potency, researchers believe they may be able to overcome drug resistance.
The drug-resistant bacterium MRSA (short for methicillin-resistant Staphylococcus aureus) is one of the biggest causes of hospital-acquired infections in the US. The Centers for Disease Control and Prevention (CDC) say the superbug commonly spreads in hospitals when contaminated health workers unwittingly pass it to patients via their hands.
Once vulnerable patients acquire MRSA, they can become seriously ill with pneumonia and other potentially fatal conditions.
MRSA has evolved several mechanisms of drug resistance. One of the ways it resists conventional antibiotics - like penicillins, cephalosporins and carbapenems - is by producing enzymes that inactivate them.
There have been several attempts to develop new agents to defeat these enzymes, but without much success. But in this new study, a team led by Chuanbing Tang, an assistant professor of chemistry and biochemistry at the University of South Carolina in the US, describes a recently discovered class of agent that tells a different story.
Several strains of MRSA were defeated by new agent and conventional antibiotics
The team found that several strains of MRSA succumbed to conventional antibiotics, like penicillin-G, amoxicillin, ampicillin, and cefazolin, when they were paired with the new agents - large, metal-containing molecules called metallopolymers.
A polymer-antibiotic combination successfully destroyed the protective membranes of MRSA bacteria, causing the "superbug" cells to explode.
They showed how the polymer-antibiotic combination avoided the bacterium's defensive enzymes and proceeded to destroy its protective membrane, causing the superbug cell to burst.
They also think the agents will have minimal side effects, since they appeared to leave red blood cells alone.
The researchers conclude:
"These discoveries could provide a new pathway for designing macromolecular scaffolds to regenerate vitality of conventional antibiotics to kill multidrug-resistant bacteria and superbugs."
Funds from the National Science Foundation helped finance the study.
Meanwhile, Medical News Today recently learned how it may be possible to create a new generation of superbug-busters from small protein molecules called peptides, which can attack bacteria in several different ways. The German team behind the research says the peptides attack bacteria cells without harming human cells, while also making it difficult for them to become resistant.
Written by Catharine Paddock PhD