Roadkill Microbiome

For an avid drug discovery spectator, a story about a biologist traveling to the geographic end of the Earth or an environment not yet examined by humans is nothing new. Faced with less effective antibiotics due to overuse, clinicians and drug developers are clamoring to find viable replacements for treatments with waning efficacy, making these adventurous stories more common. But even those who are familiar with zealous drug discovery efforts might be surprised by the research undertaken previously by a team of chemists and microbiologists from the University of Oklahoma: they sought new drug candidate molecules in roadkill.


As discussed in The American Chemical Society’s Journal of Natural Products, the team developed a protocol to find and use “fresh” roadkill on the side of a highway to explore mammalian microbiomes for bacteria that hold properties that could be useful for drugs. The published study focuses specifically on samples collected from the ear of a roadkill opossum but the research left no carcass unturned.


Why roadkill? Well, the team chose to explore roadkill microbiomes because they saw the human microbiome as a crowded research space, leaving other mammalian systems ripe for investigation. Okay, the animal focus makes sense but why dead animals? Here again the researchers made a logical choice - they wanted to avoid the ethical pressures and dilemmas that can arise in live animal testing. So, after jumping circumventing a few regulatory hurdles, including one related to animal carcass possession, the team was clear to start roadside collection of the various roadkill microbiomes.


With plenty of biological samples, the researchers set to work narrowing down the deer, raccoon, skunk, armadillo, squirrel, and opossum microbiomes to bacterial isolates and compounds that had the potential for drug development. They did this vetting using genomic analysis, among other tools and techniques. The most convincing results of their roadkill research turned out to be two bacterial isolates culled from an opossum ear. As the publication explains, these isolates were shown to limit fungal cells’ biofilm formation, making them attractive for potential development.


As microbiome research in humans and other species continues at breakneck speed, stories like this remind us 1) that we can never be too sure about where the next breakthrough in drug development will come from 2) metagenomics and its related tools are increasingly valuable, and 3) the importance of staying curious. This story just may also make it easier for you to bear the emotional burden next time you take the life of a defenseless animal with your fender. Just tell yourself, “it’s for science.”