“Flesh-eating bacteria” is a phrase that is likely to send a shiver up anyone’s spine. Though infections of this kind are rare, they are often serious. Now, a new compound is poised to change how they are treated.
“The potential drug could be the first of an entirely new class of antibiotics, and a gift to clinicians seeking more effective treatments against bacteria that can’t be tamed easily with current antibiotics,” said a Friday press release from the Washington University School of Medicine in St. Louis, Mo.
Scott Hultgren, the Helen L. Stoever Professor of Molecular Microbiology and Michael Caparon, a professor of molecular microbiology – both of Washington University – were part of the team, as well as Fredrik Almqvist, a professor of chemistry at the University of Umeå in Sweden.
Researchers found that the “novel compound” effectively cleared bacterial infections in mice, including “flesh-eating” illnesses. It targets gram-positive bacteria that can result in drug-resistant staph infections, toxic shock syndrome and more. Specifically, the study published Friday in the Science Advances journal focused on Streptococcus pyogenes.
Washington University School of Medicine said this pathogen is responsible for 500,000 deaths every year globally, including flesh-eating disease. According to the U.S. Centers for Disease Control and Prevention, Streptococcus (also known as group A strep) infections have been increasing in the country over the past decade. These infections have been increasing primarily in adults.
Streptococcus bacteria are also thought to be the main cause of necrotizing fasciitis, or flesh-eating bacterial infections. Approximately 20% of patients with flesh-eating bacterial infections die.
Per the CDC, these infections can develop very quickly into life-threatening emergencies. At first, they start with symptoms such as a red, swollen area, fever and severe pain. Then, those with necrotizing fasciitis can develop skin color changes, diarrhea or nausea, dizziness, fatigue (tiredness), pus or oozing from the infected area and ulcers, blisters, or black spots on the skin. Eventually, necrotizing fasciitis can lead to organ failure, sepsis, shocks, and life-long complications such as limb loss and severe scarring.
Previously, members of the research team found a new family of compounds they called gram-positive-icides, or GmPcides that were able to wipe out bacteria strains in petri dishes.
“It’s based on a type of molecule called ring-fused 2-pyridone,” said the university of the new compound. “Initially, Caparon and Hultgren had asked Almqvist to develop a compound that might prevent bacterial films from attaching to the surface of urethral catheters, a common cause of hospital-associated urinary tract infections. Discovering that the resulting compound had infection-fighting properties against multiple types of bacteria was a happy accident.”
In a 2022 study, Hultgren and other researchers found that “GmPcides hold potential to be used alone and in combination with existing antibiotics to combat antibiotic resistant infections caused by Gram-positive bacteria.”
“All of the gram-positive bacteria that we’ve tested have been susceptible to that compound. That includes enterococci, staphylococci, streptococci, C. difficile, which are the major pathogenic bacteria types,” said Caparon, the co-senior author of the study published this week. “The compounds have broad-spectrum activity against numerous bacteria,”
Since the GMPcides kill so much bacteria, it appears that they do not leave behind cells that would carry on mutations and develop into antibiotic resistant bacteria. While researchers are still not clear about how the compounds tackle bacteria, a microscopic examination revealed that it might be linked to the outer wrapping of bacteria cells.
“One of the jobs of a membrane is to exclude material from the outside,” Caparon explained. “We know that within five to ten minutes of treatment with GmPcide, the membranes start to become permeable and allow things that normally should be excluded to enter into the bacteria, which suggests that those membranes have been damaged.”
Once the membranes are damaged, the cell’s functions can be disrupted. According to the recent study, mice treated with the GmPcide compound had less weight loss and smaller ulcers.
“The compound appeared to reduce the virulence of the bacteria and, remarkably, speed up postinfection healing of the damaged areas of the skin,” said the press release.
This is a positive step forward, but the researchers noted that there is still a long way to go before these treatments would be available to the public. So far, Caparon, Hultgren and Almqvist have patented the compound used in the study and licensed it to QureTech Bio. They hope to pursue pharmaceutical development and clinical trials in the future.