title: Deconjugated Bile Salts Produced by Extracellular Bile-Salt Hydrolase-Like Activities from the ProbioticLactobacillus johnsoniiLa1 InhibitGiardia duodenalis In vitroGrowth.
abstract: Giardiasis, currently considered a neglected disease, is caused by the intestinal protozoan parasiteGiardia duodenalisand is widely spread in human as well as domestic and wild animals. The lack of appropriate medications and the spread of resistant parasite strains urgently call for the development of novel therapeutic strategies. Host microbiota or certain probiotic strains have the capacity to provide some protection against giardiasis. By combining biological and biochemical approaches, we have been able to decipher a molecular mechanism used by the probiotic strainLactobacillus johnsoniiLa1 to preventGiardiagrowthin vitro. We provide evidence that the supernatant of this strain contains active principle(s) not directly toxic toGiardiabut able to convert non-toxic components of bile into components highly toxic toGiardia. By using bile acid profiling, these components were identified as deconjugated bile-salts. A bacterial bile-salt-hydrolase of commercial origin was able to mimic the properties of the supernatant. Mass spectrometric analysis of the bacterial supernatant identified two of the three bile-salt-hydrolases encoded in the genome of this probiotic strain. These observations document a possible mechanism by whichL. johnsoniiLa1, by secreting, or releasing BSH-like activity(ies) in the vicinity of replicatingGiardiain an environment where bile is present and abundant, can fight this parasite. This discovery has both fundamental and applied outcomes to fight giardiasis, based on local delivery of deconjugated bile salts, enzyme deconjugation of bile components, or natural or recombinant probiotic strains that secrete or release such deconjugating activities in a compartment where both bile salts andGiardiaare present.
authors.affiliation: Laboratoire de Génétique et Pathologie des Mollusques Marins, Unité SG2M, IFREMER La Tremblade, France.
authors.forename: Marie-Agnès
authors.initials: MA
authors.lastname: Travers
authors.affiliation: MCAM UMR 7245, Muséum National d'Histoire Naturelle, Centre National de la Recherche Scientifique, Sorbonne Universités Paris, France.
authors.forename: Cissé
authors.initials: C
authors.lastname: Sow
authors.affiliation: MCAM UMR 7245, Muséum National d'Histoire Naturelle, Centre National de la Recherche Scientifique, Sorbonne Universités Paris, France.
authors.forename: Séverine
authors.initials: S
authors.lastname: Zirah
authors.affiliation: MCAM UMR 7245, Muséum National d'Histoire Naturelle, Centre National de la Recherche Scientifique, Sorbonne Universités Paris, France.
authors.forename: Christiane
authors.initials: C
authors.lastname: Deregnaucourt
authors.affiliation: MCAM UMR 7245, Muséum National d'Histoire Naturelle, Centre National de la Recherche Scientifique, Sorbonne Universités Paris, France.
authors.forename: Soraya
authors.initials: S
authors.lastname: Chaouch
authors.affiliation: Department of Cell Biology, Institute of Biology, University of Brasilia Brasília, Brazil.
authors.forename: Rayner M L
authors.initials: RM
authors.lastname: Queiroz
authors.affiliation: Department of Cell Biology, Institute of Biology, University of Brasilia Brasília, Brazil.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Charneau
authors.affiliation: MCAM UMR 7245, Muséum National d'Histoire Naturelle, Centre National de la Recherche Scientifique, Sorbonne UniversitésParis, France; UMR 1319, Commensal and Probiotics-Host Interactions Laboratory, INRA, AgroParisTechJouy en Josas, France.
authors.forename: Thibault
authors.initials: T
authors.lastname: Allain
authors.affiliation: MCAM UMR 7245, Muséum National d'Histoire Naturelle, Centre National de la Recherche Scientifique, Sorbonne Universités Paris, France.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Florent
authors.affiliation: MCAM UMR 7245, Muséum National d'Histoire Naturelle, Centre National de la Recherche Scientifique, Sorbonne Universités Paris, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Grellier
keywords: anti-giardial activity; bile salts; choloylglycine bile acid hydrolase; giardiasis; lactobacilli; microbiota; probiotics