title: SmcL, a novel membrane-damaging virulence factor in Listeria.
abstract: We describe here the fourth listerial membrane-damaging virulence factor, a sphingomyelinase C (SMase) that is produced specifically by the ruminant pathogen Listeria ivanovii. Its coding gene, smcL, is a monocistron expressed independently of PrfA. The smcL product, SmcL, is highly similar to the staphylococcal beta-toxin and is responsible for the differential hemolytic properties of L. ivanovii (bizonal hemolysis and CAMP-like reaction with R. equi). The role of SmcL in virulence was assessed by gene disruption and complementation. Our data show that SmcL mediates disruption of the membrane of primary phagosomes, thereby promoting bacterial intracellular proliferation. They also suggest that SmcL may play a role in host tropism. smcL is located in LIPI-2, a novel 18-kb pathogenicity island which also contains a cluster of internalin genes. LIPI-2 is unstable, L. ivanovii-specific and required for full virulence in mice and lambs.
authors: Grupo de Patogénesis Molecular Bacteriana, Facultad de Veterinaria, Universidad Complutense de Madrid, Spain.
authors: B
authors: B
authors: González-Zorn
authors: G
authors: G
authors: Domínguez-Bernal
authors: M
authors: M
authors: Suárez
authors: M T
authors: MT
authors: Ripio
authors: Y
authors: Y
authors: Vega
authors: S
authors: S
authors: Novella
authors: A
authors: A
authors: Rodríguez
authors: I
authors: I
authors: Chico
authors: A
authors: A
authors: Tierrez
authors: J A
authors: JA
authors: Vázquez-Boland
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D002455:Cell Division / Q000187:drug effects; D002462:Cell Membrane / Q000187:drug effects*; D008087:Listeria / Q000235:genetics / Q000472:pathogenicity*; D051379:Mice; D008969:Molecular Sequence Data; D010588:Phagosomes / Q000187:drug effects; D013108:Sphingomyelin Phosphodiesterase / Q000235:genetics / Q000633:toxicity*; D014158:Transcription, Genetic; D014774:Virulence
chemical_list: D013108:Sphingomyelin Phosphodiesterase