title: Permissiveness of freshly isolated environmental strains of amoebae for growth of Legionella pneumophila.
abstract: Legionella pneumophila is a pathogenic bacterium commonly found in water and responsible for severe pneumonia. Free-living amoebae are protozoa also found in water, which feed on bacteria by phagocytosis. Under favorable conditions, some L. pneumophila are able to resist phagocytic digestion and even multiply within amoebae. However, it is not clear whether L. pneumophila could infect at a same rate a large range of amoebae or if there is some selectivity towards specific amoebal genera or strains. Also, most studies have been performed using collection strains and not with freshly isolated strains. In our study, we assess the permissiveness of freshly isolated environmental strains of amoebae, belonging to three common genera (i.e. Acanthamoeba, Naegleria and Vermamoeba), for growth of L. pneumophila at three different temperatures. Our results indicated that all the tested strains of amoebae were permissive to L. pneumophila Lens and that there was no significant difference between the strains. Intracellular proliferation was more efficient at a temperature of 40°C. In conclusion, our work suggests that, under favorable conditions, virulent strains of L. pneumophila could equally infect a large number of isolates of common freshwater amoeba genera.
authors.affiliation: Université de Poitiers, Laboratoire Ecologie et Biologie des Interactions, CNRS UMR 7267, Equipe Microbiologie de l'Eau 1 rue Georges Bonnet, 86073 Poitiers Cedex, France EDF, Division Recherche et Développement, 6 Quai Watier, 78401 Chatou, France.
authors.forename: Mathieu
authors.initials: M
authors.lastname: Dupuy
authors.affiliation: EDF, Division Recherche et Développement, 6 Quai Watier, 78401 Chatou, France.
authors.forename: Marie
authors.initials: M
authors.lastname: Binet
authors.affiliation: EDF, Division Recherche et Développement, 6 Quai Watier, 78401 Chatou, France.
authors.forename: Celine
authors.initials: C
authors.lastname: Bouteleux
authors.affiliation: EDF, Division Recherche et Développement, 6 Quai Watier, 78401 Chatou, France.
authors.forename: Pascaline
authors.initials: P
authors.lastname: Herbelin
authors.affiliation: EDF, Division Recherche et Développement, 6 Quai Watier, 78401 Chatou, France.
authors.forename: Sylvie
authors.initials: S
authors.lastname: Soreau
authors.affiliation: Université de Poitiers, Laboratoire Ecologie et Biologie des Interactions, CNRS UMR 7267, Equipe Microbiologie de l'Eau 1 rue Georges Bonnet, 86073 Poitiers Cedex, France yann.hechard@univ-poitiers.fr.
authors.forename: Yann
authors.initials: Y
authors.lastname: Héchard
mesh_terms: D000048:Acanthamoeba / Q000382:microbiology*; D016952:Legionella pneumophila / Q000254:growth & development*; D009253:Naegleria / Q000382:microbiology*; D013696:Temperature; D014871:Water Microbiology
keywords: Legionella; amoeba; environment; infection; water