The Asgard archaea are a globally distributed group of microorganisms with significant links to eukaryotes. Despite their global presence and potential implications for our understanding of evolution, viruses that infect these organisms remain understudied and poorly understood.

In this episode, we discuss the fascinating work of Dr. Leao, who has shed light on the nature of these viruses. Using metagenome sequences from deep-sea hydrothermal sediments, Dr. Leao and his team characterized six relatively large double-stranded DNA (dsDNA) viral genomes that infect two Asgard archaeal phyla, Lokiarchaeota and Helarchaeota.

These Asgard viruses are intriguing as they show features of both prokaryotic and eukaryotic viruses, suggesting a unique evolutionary history. They possess Caudovirales-like structural proteins and a percentage of t ...