One of the potential threats that the human species must soon face is antibiotic-resistant bacteria. As bacteria continue evolving to become resistant to the medicines that we use to treat them, previously-curable infections become “superbugs” and come back stronger and more dangerous.

Some experts believe that superbugs could lead to 10 million human deaths per year by 2050, so to fortify our defenses, scientists have been on the hunt for new drugs from a range of sources, like green tea, tobacco flowers, human breast milk, rattlesnake venom, frog skin, fungi, and platypus milk.

However, researchers at the University of Pennsylvania found that humans may not have to look too far for new natural antibiotics—it turns out that there are already dozens of potential antimicrobial peptides (AMPs) inside our bodies already.

The team utilized a “search” algorithm, similar to the search function for finding keywords in a document, to find peptides with antimicrobial properties within the human proteome, the complete library of proteins produced in the body.

Their initial search focused on peptides with characteristics common to all AMPs and resulted in 2,603 hits, none of which were connected to the immune system. Next, the researchers chose 55 of these peptides to test how well they could fight off eight pathogenic bacteria such as E. coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Staphylococcus aureus.

“We found that 63.6 percent of these 55 encrypted peptides displayed antimicrobial activity,” reported the lead researcher César de la Fuente. “Interestingly, these peptides not only fought off infection by some of the most harmful bacteria in the world, they also targeted gut and skin commensal organisms that are beneficial to us. We speculate that this could be indicative of a microbiota modulating role that these peptides may possess as well.”

In tests involving mice, the team discovered that when the AMPs were grouped with others from the same region of the body, they were 100 times more powerful, and performed as well as existing antibiotics.

These findings may just lead to new natural antibiotics that will help us combat the increasingly threatening superbugs, as well as help scientists uncover hidden therapeutic molecules that can fight off other illnesses and diseases.

Source study: Natural Biomedical Engineering—Mining for encrypted peptide antibiotics in the human proteome