title: Structure of bacteriophage SPP1 tail reveals trigger for DNA ejection.
abstract: The majority of known bacteriophages have long noncontractile tails (Siphoviridae) that serve as a pipeline for genome delivery into the host cytoplasm. The tail extremity distal from the phage head is an adsorption device that recognises the bacterial receptor at the host cell surface. This interaction generates a signal transmitted to the head that leads to DNA release. We have determined structures of the bacteriophage SPP1 tail before and after DNA ejection. The results reveal extensive structural rearrangements in the internal wall of the tail tube. We propose that the adsorption device-receptor interaction triggers a conformational switch that is propagated as a domino-like cascade along the 1600 A-long helical tail structure to reach the head-to-tail connector. This leads to opening of the connector culminating in DNA exit from the head into the host cell through the tail tube.
authors.affiliation: School of Crystallography, Birkbeck College, University of London, London, UK.
authors.forename: Celia
authors.initials: C
authors.lastname: Plisson
authors.forename: Helen E
authors.initials: HE
authors.lastname: White
authors.forename: Isabelle
authors.initials: I
authors.lastname: Auzat
authors.forename: Amineh
authors.initials: A
authors.lastname: Zafarani
authors.forename: Carlos
authors.initials: C
authors.lastname: São-José
authors.forename: Sophie
authors.initials: S
authors.lastname: Lhuillier
authors.forename: Paulo
authors.initials: P
authors.lastname: Tavares
authors.forename: Elena V
authors.initials: EV
authors.lastname: Orlova
mesh_terms: D001435:Bacteriophages / Q000235:genetics*; D004279:DNA, Viral / Q000737:chemistry* / Q000235:genetics / Q000648:ultrastructure; D008854:Microscopy, Electron
chemical_list: D004279:DNA, Viral