Bacteriophages, viruses infecting bacteria, are the most abundant living entities on Earth. They are present in all ecosystems where bacteria develop and are instrumental in the regulation, diversity, evolution, and pathogeny of microbial populations. Moreover, with the increasing number of pathogenic strains resistant to antibiotics, virulent phages are considered a serious alternative or complement to classical treatments. 96% of all phages present a tail that allows host recognition and safe channelling of the DNA to the host cytoplasm.
In thie study, researchers from the Membrane and Pathogens Group present the atomic model of the proximal extremity of the siphophage T5 tail, confirming structural similarities with other phages. This structure, combined with results previously published and further explored, also allowed a review and a discussion on the role and localization of a mysterious tail protein, the tail completion protein, which is known to be present in the phage tails, but that was never identified in a phage structure.
About bacteriophage tail terminator and tail completion proteins : structure of the proximal extremity of siphophage T5 tail. Linares R, Breyton C. Journal of Virology 2025 Jan 31 ;99(1):e0137624.
Contact : Cécile Breyton (IBS/Membrane and Pathogens Group)