title: Lactococcus lactisphage TP901-1 as a model forSiphoviridaevirion assembly.
abstract: Phages infectingLactococcus lactispose a serious threat to the dairy fermentation sector. Consequently, they are among the most thoroughly characterized Gram positive-infecting phages. The majority of lactococcal phages belong to the tailed family of phages named theSiphoviridae. The coliphage lambda and theBacillus subtilisphage SPP1 have been the predominant comparators for emerging siphophages both genomically and structurally and both phages recognize a membrane protein receptor. In contrast, the lactococcal P335 group phage TP901-1 attaches to cell wall surface polysaccharides. It is a typical "lambdoid" siphophage possessing a long non-contractile tail and a genomic architecture reminiscent of lambda and SPP1 despite low or undetectable sequence homology in many of its encoded products, especially those involved in host recognition. A functional analysis of the structural components of TP901-1 was undertaken based on the characterization of a series of mutants in the region encoding the capsid and tail morphogenetic elements. Through this analysis, it was possible to deduce that, despite the lack of sequence homology, the overall genomic architecture ofSiphoviridaephages typified by functional synteny is conserved. Furthermore, a model of the TP901-1 assembly pathway was developed with potential implications for many tailed phages.
authors.affiliation: School of Microbiology, University College Cork , Cork, Ireland.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Mahony
authors.affiliation: School of Microbiology, University College Cork, Cork, Ireland; APC Microbiome Institute, University College Cork, Cork, Ireland.
authors.forename: Stephen R
authors.initials: SR
authors.lastname: Stockdale
authors.affiliation: School of Microbiology, University College Cork , Cork, Ireland.
authors.forename: Barry
authors.initials: B
authors.lastname: Collins
authors.affiliation: Aix-Marseille Université, Architecture et Fonction des Macromolécules Biologiques, Campus de Luminy , Marseille Cedex, France.
authors.forename: Silvia
authors.initials: S
authors.lastname: Spinelli
authors.affiliation: School of Microbiology, University College Cork , Cork, Ireland.
authors.forename: Francois P
authors.initials: FP
authors.lastname: Douillard
authors.affiliation: Aix-Marseille Université, Architecture et Fonction des Macromolécules Biologiques, Campus de Luminy, Marseille Cedex, France; Centre National de la Recherche Scientifique, AFMB, Campus de Luminy, Marseille Cedex, France.
authors.forename: Christian
authors.initials: C
authors.lastname: Cambillau
authors.affiliation: School of Microbiology, University College Cork, Cork, Ireland; APC Microbiome Institute, University College Cork, Cork, Ireland.
authors.forename: Douwe
authors.initials: D
authors.lastname: van Sinderen
keywords: Siphoviridae; Western blot; electron microscopy; phage evolution; phage precipitation; structure-function