title: First Description of Sulphur-Oxidizing Bacterial Symbiosis in a Cnidarian (Medusozoa) Living in Sulphidic Shallow-Water Environments.
abstract: BACKGROUND
  Since the discovery of thioautotrophic bacterial symbiosis in the giant tubeworm Riftia pachyptila, there has been great impetus to investigate such partnerships in other invertebrates. In this study, we present the occurrence of a sulphur-oxidizing symbiosis in a metazoan belonging to the phylum Cnidaria in which this event has never been described previously.
  
  
  RESULTS
  Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM) observations and Energy-dispersive X-ray spectroscopy (EDXs) analysis, were employed to unveil the presence of prokaryotes population bearing elemental sulphur granules, growing on the body surface of the metazoan. Phylogenetic assessments were also undertaken to identify this invertebrate and microorganisms in thiotrophic symbiosis. Our results showed the occurrence of a thiotrophic symbiosis in a cnidarian identified as Cladonema sp.
  
  
  CONCLUSIONS
  This is the first report describing the occurrence of a sulphur-oxidizing symbiosis in a cnidarian. Furthermore, of the two adult morphologies, the polyp and medusa, this mutualistic association was found restricted to the polyp form of Cladonema sp.
authors.affiliation: Institut de Biologie Paris-Seine, UMR 7138-Evolution Paris-Seine, Equipe Biologie de la Mangrove. Université des Antilles et de la Guyane, UFR des Sciences Exactes et Naturelles, Département de Biologie, BP 592. 97159 Pointe-à-Pitre cedex, Guadeloupe, France.
authors.forename: Sylvie
authors.initials: S
authors.lastname: Abouna
authors.affiliation: Institut de Biologie Paris-Seine, UMR 7138-Evolution Paris-Seine, Equipe Biologie de la Mangrove. Université des Antilles et de la Guyane, UFR des Sciences Exactes et Naturelles, Département de Biologie, BP 592. 97159 Pointe-à-Pitre cedex, Guadeloupe, France.
authors.forename: Silvina
authors.initials: S
authors.lastname: Gonzalez-Rizzo
authors.affiliation: Institut de Biologie Paris-Seine, UMR 7138-Evolution Paris-Seine, Equipe Biologie de la Mangrove. Université des Antilles et de la Guyane, UFR des Sciences Exactes et Naturelles, Département de Biologie, BP 592. 97159 Pointe-à-Pitre cedex, Guadeloupe, France.
authors.forename: Adrien
authors.initials: A
authors.lastname: Grimonprez
authors.affiliation: Institut de Biologie Paris-Seine, UMR 7138-Evolution Paris-Seine, Equipe Biologie de la Mangrove. Université des Antilles et de la Guyane, UFR des Sciences Exactes et Naturelles, Département de Biologie, BP 592. 97159 Pointe-à-Pitre cedex, Guadeloupe, France; C3MAG, UFR des Sciences Exactes et Naturelles, Université des Antilles et de la Guyane, BP 592. 97159 Pointe-à-Pitre, Guadeloupe (French West Indies).
authors.forename: Olivier
authors.initials: O
authors.lastname: Gros
mesh_terms: D000818:Animals; D003063:Cnidaria / Q000033:anatomy & histology / Q000378:metabolism* / Q000648:ultrastructure; D004777:Environment; D008969:Molecular Sequence Data; D010084:Oxidation-Reduction; D010802:Phylogeny; D013440:Sulfides / Q000378:metabolism*; D013455:Sulfur / Q000378:metabolism*; D013559:Symbiosis; D014867:Water
chemical_list: D013440:Sulfides; D014867:Water; D013455:Sulfur