Antibiotic resistance is a growing global threat with drug-resistant bacterial infections being one of the leading causes of death in developing countries. Despite this, there have been no new antibiotics launched for public use in the last four decades. Overprescription of antibiotics by doctors and rampant abuse in agriculture and animal husbandry industries are exacerbating the situation.
However, a group of researchers found that an 80-year-old antibiotic called nourseothricin might offer some protection against drug-resistant bacterial infections. Nourseothricin was discovered in the early 1940s as a powerful antibiotic that could tackle many pathogenic bacteria. Plans to mass-produce the antibiotic were dropped because it proved to be extremely toxic to kidneys.
The researchers found that different forms of nourseothricin's complex molecule called streptothricin have different levels of toxicity. Specifically, streptothricin-F is significantly less toxic than the other forms and highly effective in fighting against drug-resistant pathogens.
In a new study published in PLOS Biology, the researchers delved into how two forms of streptothricin (F and D) worked against pathogens and further detailed their renal toxicity. They found that streptothricin-F was effective against drug-resistant pathogenic bacteria like carbapenem-resistant Enterobacterales and Acinetobacter baumannii, boasting at least 10-fold lower toxicity than streptothricin-D.
After injecting mice with the streptothricin-F molecule, the researchers reported that there was minimal or almost no renal toxicity. The researchers believe that the streptothricin scaffold deserves further pre-clinical exploration as a potential therapeutic for the treatment of multidrug-resistant bacterial pathogens.