title: X-ray structure of a superinfection exclusion lipoprotein from phage TP-J34 and identification of the tape measure protein as its target.
abstract: Lipoproteins of temperate phage are a broad family of membrane proteins encoded in the lysogeny module of temperate phages. Expression of the ltp(TP-J34) gene of temperate Streptococcus thermophilus phage TP-J34 interferes with phage infection at the stage of triggering DNA release and injection into the cell. Here, we report the first structure of a superinfection exclusion protein. We have expressed and determined the X-ray structure of Ltp(TP-J34). The soluble domain of Ltp(TP-J34) is composed of a tandem of three-helix helix-turn-helix (HTH) domains exhibiting a highly negatively charged surface. By isolating mutants of lactococcal phage P008wt with reduced sensitivities to Ltp(TP-J34) and by genome sequencing of such mutants we obtained evidence supporting the notion that Ltp(TP-J34) targets the phage's tape measure protein (TMP) and blocks its insertion into the cytoplasmic membrane.
authors.affiliation: Architecture et Fonction des Macromolecules Biologiques, UMR 7257, CNRS and Aix-Marseille University, Case 932, 163 Avenue de Luminy, 13288, Marseille, Cedex 09, France.
authors.forename: Cecilia
authors.initials: C
authors.lastname: Bebeacua
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: Lorenzo Fajardo
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Blangy
authors.forename: Silvia
authors.initials: S
authors.lastname: Spinelli
authors.forename: Stefanie
authors.initials: S
authors.lastname: Bollmann
authors.forename: Horst
authors.initials: H
authors.lastname: Neve
authors.forename: Christian
authors.initials: C
authors.lastname: Cambillau
authors.forename: Knut J
authors.initials: KJ
authors.lastname: Heller
mesh_terms: D018360:Crystallography, X-Ray; D008074:Lipoproteins / Q000737:chemistry* / Q000378:metabolism*; D008242:Lysogeny; D039002:Prophages / Q000737:chemistry; D011487:Protein Conformation; D017108:Streptococcus Phages / Q000737:chemistry*; D048249:Streptococcus thermophilus / Q000821:virology; D014764:Viral Proteins / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D008074:Lipoproteins; D014764:Viral Proteins