SEATTLE — Researchers at the University of Tubingen in Germany are looking to the human body as a new source of drugs to treat antibiotic-resistant strains of bacteria. They have found a promising gene for a new antibiotic, named lugdunin, in the mucus lining our nasal passages.
Antibiotics are among the most common treatments against bacterial infections. Ever since Alexander Fleming’s famous discovery of penicillin in the early 20th century, considered by many to be the first antibiotic treatment, doctors have prescribed antibiotics to treat illnesses ranging from syphilis to food poisoning.
Like vaccines, the production, distribution and widespread use of antibiotics worldwide has extended human longevity by lowering death rates associated with gastrointestinal illnesses, infections of the respiratory system and infections of the immune system.
Yet, despite saving countless lives and improving population health, antibiotics are also a source of concern within the medical community. Simply put, antibiotics treat illnesses by killing the causative bacteria. The problem is, bacterial strains adapt incredibly fast.
As more and more people use antibiotics to treat common illnesses, bacteria adapt to make us sick in new ways. The result? Multidrug-resistant bacteria that can lead to debilitating, or even deadly illnesses.
Multidrug-resistant bacteria are never good, but they are especially threatening to the developing world, where unsanitary medical conditions can serve as the perfect breeding ground for life-threatening diseases.
Without effective antibiotics, health professionals are unable to control viral bacterial illnesses like tuberculosis and pneumonia. In fact, drug-resistant superbugs are estimated to be responsible for 700,000 deaths per year worldwide.
The World Health Organization estimates that in 2014, 27 countries qualified as “high burden” for their incidence of drug-resistant tuberculosis. Countries with the highest numbers include developing nations like Bangladesh, the Democratic Republic of the Congo, Ethiopia and Myanmar.
Incentivizing pharmaceutical companies to create newer antibiotics has been a long-running problem; the most recent class of antibiotics was discovered in the 1980s. Meanwhile, the growing rate of drug-resistant illnesses in the developing world make newer, more effective antibiotics a major priority of the global health community.
On a microscopic level, millions of bacteria are competing within our bodies for food and shelter. One of these species is Staphylococcus aureus, the same bacteria responsible for the dreaded superbug strain of MRSA, a painful skin infection characterized by fluid-filled boils that require surgical draining. S. aureus resides in the mucus of nasal passages in 30 percent of people.
Researchers at Tubingen noticed that people with a rival strain, Staphylococcus lugdunensis, were less likely to have the MRSA-causing aureus strain. Their findings suggest that the lugdunensis strain may produce its own antibiotic to wipe out its competition.
The team tested many genetically modified strains of S. lugdunensis to determine which genetic properties were responsible for its success over S. auereus. Eventually, they identified the specific gene containing instructions for creating the new antibiotic, which they named lugdunin.
Tests on mice revealed that lugdunin could treat superbug skin infections including drug-resistant MRSA, as well as urinary tract infections and bacterial meningitis.
According to a press release from Tubingen, Professor Andreas Peschel noted that“introducing the lugdunin genes into a completely innocuous bacterial species” will help “develop a new preventive concept of antibiotics that can eradicate pathogens.” He also believes that one day, humans could be intentionally infected with genetically-modified bacteria to fight infections, similar to the way that vaccines are used to prevent diseases.
Lugdunin is only effective against a limited number of bacterial infections. Yet, the approach taken by the team at Tubingen is paving the road for newer solutions to the superbug epidemic. Their research validates the human body as the new frontier for antibiotic sourcing.
– Jessica Levitan
Photo: Flickr