Event

Abstract: In the past decade, bacteria have been found to possess over 100 distinct immune pathways that protect them against viral infection. Many of these antiviral immune pathways represent ancient versions of important eukaryotic innate-immune factors or fundamental signaling pathways. I will discuss three families of bacterial immune pathways that are related to eukaryotic ubiquitination pathways. Using biochemistry, structural biology, and genetics, we and our collaborators have shown that these pathways represent bona fide protein conjugation systems with structural and mechanistic parallels to eukaryotic systems. Our findings have upended the traditional understanding of how ubiquitination pathways evolved, demonstrating that these pathways originated in the context of bacterial antiviral immunity.