The horned passalus beetle, commonly known as the bessbug, may seem gross. In addition to eating its own feces, or frass, the shiny black beetle lines its living spaces and larval chambers with its excrement. Now, new research suggests that the beetle’s frass habits are actually a clever strategy for protecting its own health, and they could help inform human medicine too.
Researchers, including postdoctoral scholar Rita de Cassia Pessotti and assistant professor of plant and microbial biology Matthew Traxler, discovered that bessbug frass is teeming with antibiotic and antifungal chemicals, similar to the ones that humans use to ward off bacterial and fungal infections. These compounds are made by beneficial bacteria called actinomycetes that live in the beetle’s frass, appearing to be passed from beetle to beetle, and from colony to colony, through coprophagy—the technical term for eating feces.
With the discovery, bessbug beetles join a handful of other insects that benefit from symbiotic relationships with actinomycetes. Understanding the relationship between the bessbug beetles, actinomycetes, and antimicrobials could help scientists develop new antibiotic drugs and assist doctors developing strategies for combating antibiotic-resistant infections.
“When scientists discover a new antibiotic, it often only takes a few years before the pathogen starts to develop antibiotic resistance, but these microbes have been using the same molecules for millions of years,” said Traxler. “Learning more about their strategies could inform key breakthroughs for human health.”
— Adapted from an article by Kara Manke