title: Probiotic Enterococcus faecalis Symbioflor®down regulates virulence genes of EHEC in vitro and decrease pathogenicity in a Caenorhabditis elegans model.
abstract: Enterohemorrhagic E. coli O157:H7 (EHEC) shorten the lifespan of Caenorhabditis elegans compared to avirulent bacteria. Co-feeding EHEC with Enterococcus faecalis Symbioflor®significantly increased the worms' lifespan. The transcriptome of EHEC grown in vitro with or without Symbioflor®was analyzed using RNA-seq. The analysis revealed downregulation of several virulence-associated genes in the presence of Symbioflor®, including virulence key genes (e.g., LEE, flagellum, quorum-sensing). The downregulation of the LEE genes was corroborated by lux-transposon mutants. Upregulated genes included acid response genes, due to a decrease in pH exerted by Symbioflor®. Further genes indicate cellular stress in EHEC (e.g. prophage/mobile elements involved in excision, cell lysis, and cell division inhibition). Thus, the observed protection of C. elegans during an EHEC infection by the probiotic Symbioflor®is suggested to be caused by triggering concomitant transcriptomic changes. To verify the biological relevance of this modulation, exemplary genes found to be influenced by Symbioflor®were knocked out (fliD, espB, Z3136, Z3917, and L7052). The lifespan of nematodes changed when using knock-outs as food source and the effect could be complemented in trans. In summary, Symbioflor®appears to be a protective probiotic in the nematode model.
authors.affiliation: Lehrstuhl für Mikrobielle Ökologie, Wissenschaftszentrum Weihenstephan, Technische Universität München, Weihenstphaner Berg 3, 85350, Freising, Germany.
authors.forename: Klaus
authors.initials: K
authors.lastname: Neuhaus
authors.affiliation: Lehrstuhl für Technische Mikrobiologie, Wissenschaftszentrum Weihenstephan, Technische Universität München, Gregor-Mendel-Str. 4, 85354, Freising, Germany.|Bundesintitut für Risikobewertung, Max-Dohrn-Str. 8-10, 10589, Berlin, Germany.
authors.forename: Marina C
authors.initials: MC
authors.lastname: Lamparter
authors.affiliation: Lehrstuhl für Mikrobielle Ökologie, Wissenschaftszentrum Weihenstephan, Technische Universität München, Weihenstphaner Berg 3, 85350, Freising, Germany.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Zölch
authors.affiliation: Lehrstuhl für Mikrobielle Ökologie, Wissenschaftszentrum Weihenstephan, Technische Universität München, Weihenstphaner Berg 3, 85350, Freising, Germany.
authors.forename: Richard
authors.initials: R
authors.lastname: Landstorfer
authors.affiliation: Datenanalyse und Visualisierung, Fachbereich Informatik und Informationswissenschaft, Universität Konstanz, Universitätsstr. 10, 78457, Constance, Germany.
authors.forename: Svenja
authors.initials: S
authors.lastname: Simon
authors.affiliation: Lehrstuhl für Ernährungsphysiologie, Wissenschaftszentrum Weihenstephan, Technische Universität München, Gregor-Mendel-Str. 2, 85354, Freising, Germany.
authors.forename: Britta
authors.initials: B
authors.lastname: Spanier
authors.affiliation: Lehrstuhl für Technische Mikrobiologie, Wissenschaftszentrum Weihenstephan, Technische Universität München, Gregor-Mendel-Str. 4, 85354, Freising, Germany.
authors.forename: Matthias A
authors.initials: MA
authors.lastname: Ehrmann
authors.affiliation: Lehrstuhl für Technische Mikrobiologie, Wissenschaftszentrum Weihenstephan, Technische Universität München, Gregor-Mendel-Str. 4, 85354, Freising, Germany. rudi.vogel@wzw.tum.de.
authors.forename: Rudi F
authors.initials: RF
authors.lastname: Vogel
mesh_terms: D000818:Animals; D017173:Caenorhabditis elegans / Q000382:microbiology; D015536:Down-Regulation; D013293:Enterococcus faecalis / Q000502:physiology*; D019453:Escherichia coli O157 / Q000235:genetics / Q000472:pathogenicity*; D005798:Genes, Bacterial; D056265:Microbial Interactions / Q000235:genetics; D019936:Probiotics; D053038:Quorum Sensing / Q000235:genetics; D059467:Transcriptome; D037521:Virulence Factors / Q000235:genetics
chemical_list: D037521:Virulence Factors
keywords: Caenorhabditis elegans; EHEC; Enterococcus faecalis Symbioflor®; Transcriptome; Virulence; lux transposons