title: A stress protein is induced in the deep-sea barophilic hyperthermophile Thermococcus barophilus when grown under atmospheric pressure.
abstract: The whole-cell protein inventory of the deep-sea barophilic hyperthermophile Thermococcus barophilus was examined by one-dimensional SDS gradient gel electrophoresis when grown under different pressure conditions at 85 degrees C (Topt). One protein (P60) with a molecular mass of approximately 60 kDa was prominent at low pressures (0.3 MPa hydrostatic pressure and 0.1 MPa atmospheric pressure) but not at deep-sea pressures (10, 30, and 40 MPa). About 17 amino acids were sequenced from the N-terminal end of the protein. Sequence homology analysis in the GenBank database showed that P60 most closely resembled heat-shock proteins in some sulfur-metabolizing Archaea. A high degree of amino acid identity (81%-93%) to thermosome subunits in Thermococcales strains was found. Another protein (P35) with molecular mass of approximately 35.5 kDa was induced at 40 MPa hydrostatic pressure but not under low-pressure conditions. No amino acid sequence homology was found for this protein when the 40 amino acids from the N-terminal end were compared with homologous regions of proteins from databases. A PTk diagram was generated for T. barophilus. The results suggest that Phabitat is about 35 MPa, which corresponds to the in situ pressure where the strain was obtained.
authors.affiliation: Department of Biotechnology, Technological Institute of Iceland, Reykjavík, Iceland. viggo@iti.is
authors.forename: V T
authors.initials: VT
authors.lastname: Marteinsson
authors.forename: A L
authors.initials: AL
authors.lastname: Reysenbach
authors.forename: J L
authors.initials: JL
authors.lastname: Birrien
authors.forename: D
authors.initials: D
authors.lastname: Prieur
mesh_terms: D000595:Amino Acid Sequence; D001274:Atmospheric Pressure; D006360:Heat-Shock Proteins / Q000096:biosynthesis* / Q000737:chemistry; D006358:Hot Temperature; D006874:Hydrostatic Pressure; D008969:Molecular Sequence Data; D008970:Molecular Weight; D012623:Seawater / Q000382:microbiology*; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D019712:Thermococcus / Q000502:physiology*
chemical_list: D006360:Heat-Shock Proteins