Bebeacua, Cecilia3; Lai, Livia3; Vegge, Christina Skovgaard5; Brøndsted, Lone5; van Heel, Marin3; Veesler, David4; Cambillau, Christian4
1 Food Safety and Zoonoses, Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, Københavns Universitet2 Secretariat, Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, Københavns Universitet3 Imperial College4 Universités Aix-Marseille I and II5 Food Safety and Zoonoses, Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, Københavns Universitet
the structure of lactococcal phage TP901-1
Tailed phages are genome delivery machines exhibiting unequaled efficiency acquired over more than 3 billion years of evolution. Siphophages from the P335 and 936 families infect the Gram-positive bacterium Lactococcus lactis using receptor-binding proteins anchored to the host adsorption apparatus (baseplate). Crystallographic and electron microscopy (EM) studies have shed light on the distinct adsorption strategies used by phages of these two families, suggesting that they might also rely on different infection mechanisms. Here, we report electron microscopy reconstructions of the whole phage TP901-1 (P335 species) and propose a composite EM model of this gigantic molecular machine. Our results suggest conservation of structural proteins among tailed phages and add to the growing body of evidence pointing to a common evolutionary origin for these virions. Finally, we propose that host adsorption apparatus architectures have evolved in correlation with the nature of the receptors used during infection.
Journal of Virology, 2013, Vol 87, Issue 2, p. 1061-1068