Researchers in Germany have just discovered a new antibiotic that may help in the development of treatments for methicillin-resistant Staphylococcus aureus. The source of the antibiotic is the human nose, showing that the human microbiota is a possible source of effective antibiotics. The findings were just published in the journal Nature.
There is a serious need for new antibiotics to combat infections caused by bacteria that have become resistant to standard treatments. Methicillin-resistant Staphylococcus aureus, or MRSA, is a strain of bacteria that’s resistant to currently available antibiotics. MRSA infections are very difficult to treat and represent a threat to global human health.
Scientists noticed that while strains of Staphylococcus aureus were found in the majority of human noses, some people completely lacked the bacteria. In an effort to understand what was preventing colonization of the staph bacteria, the team analyzed the other microbes present in the nasal passage. They found another bacteria species, Staphylococcus lugdunensis, and speculated that it may be outcompeting rival staph bacteria by producing its own antibiotics. This type of behavior is commonly seen in soil microbiota but had never been studied in the human body.
The research team isolated the antibiotic, naming it lugdunin. They tested lugdunin on mice with S. aureus infections. The majority of the mice were cured. The researchers found that lugdunin has various bactericidal properties and may work against other infectious pathogens.
The new study is significant for two reasons. The discovery of lugdunin may lead to treatments for serious infections such as MRSA, which are currently extremely difficult to treat. The authors note that the antibiotic has only been tested in mice so far and possible side effects are unknown. They believe that even if the antibiotic itself is unsafe, scientists could potentially use gene therapy to create a safer version. The study is also significant because it points to a new source of potential antibiotics, the human body. Past antibiotic discoveries had generally been found in soil microbiota, this was the first study to consider human microbes.
Alexander Zipperer et al. Human commensals producing a novel antibiotic impair pathogen colonization. Nature (2016).