title: Sulfur vesicles from Thermococcales: A possible role in sulfur detoxifying mechanisms.
abstract: The euryarchaeon Thermococcus prieurii inhabits deep-sea hydrothermal vents, one of the most extreme environments on Earth, which is reduced and enriched with heavy metals. Transmission electron microscopy and cryo-electron microscopy imaging of T. prieurii revealed the production of a plethora of diverse membrane vesicles (MVs) (from 50 nm to 400 nm), as is the case for other Thermococcales. T. prieurii also produces particularly long nanopods/nanotubes, some of them containing more than 35 vesicles encased in a S-layer coat. Notably, cryo-electron microscopy of T. prieurii cells revealed the presence of numerous intracellular dark vesicles that bud from the host cells via interaction with the cytoplasmic membrane. These dark vesicles are exclusively found in conjunction with T. prieurii cells and never observed in the purified membrane vesicles preparations. Energy-Dispersive-X-Ray analyses revealed that these dark vesicles are filled with sulfur. Furthermore, the presence of these sulfur vesicles (SVs) is exclusively observed when elemental sulfur was added into the growth medium. In this report, we suggest that these atypical vesicles sequester the excess sulfur not used for growth, thus preventing the accumulation of toxic levels of sulfur in the host's cytoplasm. These SVs transport elemental sulfur out of the cell where they are rapidly degraded. Intriguingly, closely related archaeal species, Thermococcus nautili and Thermococcus kodakaraensis, show some differences about the production of sulfur vesicles. Whereas T. kodakaraensis produces less sulfur vesicles than T. prieurii, T. nautili does not produce such sulfur vesicles, suggesting that Thermococcales species exhibit significant differences in their sulfur metabolic pathways.
authors.affiliation: Institut de Biologie Intégrative de la cellule, Laboratoire de Biologie Cellulaire des Archaea, UMR8621/CNRS, 91405 Orsay Cedex, France. Electronic address: aurore.gorlas@igmors.u-psud.fr.
authors.forename: A
authors.initials: A
authors.lastname: Gorlas
authors.affiliation: Institut de Biologie Intégrative de la cellule, Laboratoire de Biologie Cellulaire des Archaea, UMR8621/CNRS, 91405 Orsay Cedex, France.
authors.forename: E
authors.initials: E
authors.lastname: Marguet
authors.affiliation: Institut de Biologie Intégrative de la cellule, Laboratoire de Biologie Cellulaire des Archaea, UMR8621/CNRS, 91405 Orsay Cedex, France.
authors.forename: S
authors.initials: S
authors.lastname: Gill
authors.affiliation: Laboratoire de Microbiologie des Environnements Extrêmes (LMEE), UMR 6197/UBO /IFREMER/CNRS IUEM, Place Nicolas Copernic, Technopôle Brest Iroise, 29280 Plouzané, France.
authors.forename: C
authors.initials: C
authors.lastname: Geslin
authors.affiliation: Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, Sorbonne Universités, Université Pierre et Marie Curie, UMR 7590 CNRS, Institut de Recherche pour le Développement UMR 206, Museum National d'Histoire Naturelle, 75252 Paris Cedex 05, France.
authors.forename: J-M
authors.initials: JM
authors.lastname: Guigner
authors.affiliation: Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, Sorbonne Universités, Université Pierre et Marie Curie, UMR 7590 CNRS, Institut de Recherche pour le Développement UMR 206, Museum National d'Histoire Naturelle, 75252 Paris Cedex 05, France.
authors.forename: F
authors.initials: F
authors.lastname: Guyot
authors.affiliation: Institut de Biologie Intégrative de la cellule, Laboratoire de Biologie Cellulaire des Archaea, UMR8621/CNRS, 91405 Orsay Cedex, France; Institut Pasteur, Laboratoire de Biologie Moléculaire du Gène chez les Extrémophiles, 25 rue du Docteur Roux, Paris Cedex 15, France.
authors.forename: P
authors.initials: P
authors.lastname: Forterre
mesh_terms: D008658:Inactivation, Metabolic / Q000502:physiology; D008854:Microscopy, Electron; D022142:Secretory Vesicles / Q000378:metabolism*; D013052:Spectrometry, X-Ray Emission; D013455:Sulfur / Q000378:metabolism*; D019712:Thermococcus / Q000378:metabolism*
chemical_list: D013455:Sulfur
keywords: Archaea; Detoxification; Membrane vesicles; Sulfur; Thermococcales