title: Response of Vibrio cholerae to the Catecholamine Hormones Epinephrine and Norepinephrine.
abstract: In Escherichia coli or Salmonella enterica, the stress-associated mammalian hormones epinephrine (E) and norepinephrine (NE) trigger a signaling cascade by interacting with the QseC sensor protein. Here we show that Vibrio cholerae, the causative agent of cholera, exhibits a specific response to E and NE. These catecholates (0.1 mM) enhanced the growth and swimming motility of V. cholerae strain O395 on soft agar in a medium containing calf serum, which simulated the environment within the host. During growth, the hormones were converted to degradation products, including adrenochrome formed by autooxidation with O2 or superoxide. In E. coli, the QseC sensor kinase, which detects the autoinducer AI-3, also senses E or NE. The genome of V. cholerae O395 comprises an open reading frame coding for a putative protein with 29% identity to E. coli QseC. Quantitative reverse transcriptase PCR (qRT-PCR) experiments revealed increased transcript levels of the qseC-like gene and of pomB, a gene encoding a structural component of the flagellar motor complex, under the influence of E or NE. Phentolamine blocks the response of E. coli QseC to E or NE. A V. cholerae mutant devoid of the qseC-like gene retained the phentolamine-sensitive motility in the presence of E, whereas NE-stimulated motility was no longer inhibited by phentolamine. Our study demonstrates that V. cholerae senses the stress hormones E and NE. A sensor related to the histidine kinase QseC from E. coli is identified and is proposed to participate in the sensing of NE.
  
  
  OBJECTIVE
  Vibrio cholerae is a Gram-negative bacterium that may cause cholera, a severe illness with high mortality due to acute dehydration caused by diarrhea and vomiting. Pathogenic V. cholerae strains possess virulence factors like the cholera toxin (CTX) and the toxin-coregulated pilus (TCP) produced in response to signals provided by the host. In pathogenic enterobacteria, the stress-associated hormones epinephrine (E) and norepinephrine (NE) of the human host act as signal molecules for the production of virulence factors and promote bacterial growth by the sequestration of iron from the host. Here we show that V. cholerae, like some enterobacteria, benefits from these stress hormones and possesses a sensor to recognize them.
authors.affiliation: Institute of Microbiology, University of Hohenheim (Stuttgart), Stuttgart, Germany.
authors.forename: Petra
authors.initials: P
authors.lastname: Halang
authors.affiliation: Institute of Microbiology, University of Hohenheim (Stuttgart), Stuttgart, Germany.
authors.forename: Charlotte
authors.initials: C
authors.lastname: Toulouse
authors.affiliation: Institute of Microbiology, University of Hohenheim (Stuttgart), Stuttgart, Germany.
authors.forename: Bernadette
authors.initials: B
authors.lastname: Geißel
authors.affiliation: Institute of Microbiology, University of Hohenheim (Stuttgart), Stuttgart, Germany.
authors.forename: Bernd
authors.initials: B
authors.lastname: Michel
authors.affiliation: Institute of Animal Husbandry and Animal Breeding, University of Hohenheim (Stuttgart), Stuttgart, Germany.
authors.forename: Birgit
authors.initials: B
authors.lastname: Flauger
authors.affiliation: Institute of Phytomedicine, University of Hohenheim (Stuttgart), Stuttgart, Germany.
authors.forename: Manuel
authors.initials: M
authors.lastname: Müller
authors.affiliation: Institute of Phytomedicine, University of Hohenheim (Stuttgart), Stuttgart, Germany.
authors.forename: Ralf T
authors.initials: RT
authors.lastname: Voegele
authors.affiliation: Institute of Animal Husbandry and Animal Breeding, University of Hohenheim (Stuttgart), Stuttgart, Germany.
authors.forename: Volker
authors.initials: V
authors.lastname: Stefanski
authors.affiliation: Institute of Microbiology, University of Hohenheim (Stuttgart), Stuttgart, Germany julia.steuber@uni-hohenheim.de.
authors.forename: Julia
authors.initials: J
authors.lastname: Steuber
mesh_terms: D000323:Adrenochrome / Q000096:biosynthesis; D000595:Amino Acid Sequence; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics; D004837:Epinephrine / Q000494:pharmacology*; D004926:Escherichia coli / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism*; D005407:Flagella / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects; D000071677:Histidine Kinase; D008969:Molecular Sequence Data; D009638:Norepinephrine / Q000494:pharmacology*; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism; D013481:Superoxides / Q000737:chemistry; D014734:Vibrio cholerae / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D037521:Virulence Factors / Q000235:genetics
chemical_list: D001425:Bacterial Outer Membrane Proteins; D029968:Escherichia coli Proteins; C103353:PomB protein, bacteria; C455504:QseC protein, E coli; D037521:Virulence Factors; D013481:Superoxides; D000323:Adrenochrome; D011494:Protein Kinases; D000071677:Histidine Kinase; D009638:Norepinephrine; D004837:Epinephrine