Aquifex pyrophilus gen. nov. sp. nov., Represents a Novel Group of Marine Hyperthermophilic Hydrogen-Oxidizing Bacteria

Desulfurobacterium thermolithotrophum gen. nov., sp. nov., a novel autotrophic, sulphur-reducing bacterium isolated from a deep-sea hydrothermal vent

“…The phylogenetic analysis based on the 16s rDNA sequence indicates that strain BSAT is not specifically affiliated with one of the genera already existing and represents a line of descent that is distinct and almost equidistant from the previously described deeply branching thermophilic genera (Pitulle et al, 1994). However, strain BSAT shares a secondary structural feature with members of the order AquiJicales (Burggraf et al, 1992). The helix found at positions 198-219 in the 16s rRNA secondary structure (E. coli numbering) is characterized by a CUC bulge and a single nucleotide bulge (Fig.…”

Persephonella marina gen. nov., sp. nov. and Persephonella guaymasensis sp. nov., two novel, thermophilic, hydrogen-oxidizing microaerophiles from deep-sea hydrothermal vents.

“…On the basis of the initial 16S rRNA gene sequence, an enrichment obtained from Q vent and from Rebecca's Roost, Guaymas Basin, were chosen for further study. Colonies that were flat, white and 2-3 mm in diameter appeared after 7 days in- .............................................................................................................................................................................................................................................................................................................................................................................................................. (Huber et al, 1992) ; 4, Thermocrinis ruber (Huber et al, 1998) ; 5, Calderobacterium hydrogenophilum (Kryukov et al, 1983) ; 6, Hydrogenobacter thermophilus (Kawasumi et al, 1984) ; 7, Hydrogenobacter acidophilus (Shima & Suzuki, 1993 ;Kristjansson et al, 1985) ; 8, Hydrogenobacter halophilus (Nishihara et al, 1990) cubation on Gelrite plates. The isolates were designated strains EX-H1 T and EX-H2 T .…”

“…1, bottom). Strains (reference) : 1, Strain EX-H1 T ; 2, Strain EX-H2 T ; 3, Aquifex pyrophilus (Huber et al, 1992) ; 4, Thermocrinis ruber (Huber et al, 1998) ; 5, Calderobacterium hydrogenophilum (Kryukov et al, 1983) ; 6, Hydrogenobacter thermophilus (Kawasumi et al, 1984) ; 7, Hydrogenobacter acidophilus (Shima & Suzuki, 1993) ; 8, Hydrogenobacter halophilus (Nishihara et al, 1990) ; 9, Hydrogenothermus marinus (Sto$ hr et al, 2001). , Not determined ; j, growth ; k, no growth.…”

“…Members of the Aquificales have been isolated from shallow marine (Huber et al, 1992 ;Nishihara et al, 1990) and terrestrial hydrothermal systems (Kryukov et al, 1983 ;Kawasumi et al, 1984 ;Shima & Suzuki, 1993 ;Huber et al, 1998 ;Kristjansson et al, 1985), from heated compost (Beffa et al, 1996) and, recently, from a deepsea hydrothermal vent (Reysenbach et al, 2000a). On the basis of molecular ecological analyses, the Aquificales appear to be dominant members of communities in near-neutral terrestrial thermal springs in Japan (Yamamoto et al, 1998), Iceland (Hjo$ rleifsdottir et al, 2001) and Yellowstone National…”

“…The type genus of the Aquificales is Aquifex, originally isolated from a shallow marine hydrothermal system on the Kolbeinsey Ridge, Iceland (Huber et al, 1992). Close relatives of this genus include Hydrogenobacter, which has been isolated from terrestrial thermal springs in Japan [Hydrogenobacter acidophilus (Shima & Suzuki, 1993) and Hydrogenobacter thermophilus (Kawasumi et al, 1984)] and Iceland [H. thermophilus (Kristjansson et al, 1985)] and from shallow marine springs in Japan [Hydrogenobacter halophilus (Nishihara et al, 1990)], Calderobacterium, which was isolated from terrestrial thermal springs in Kamchatka [Calderobacterium hydrogenophilum (Saveleva et al, 1982 ;Kryukov et al, 1983)] and Yellowstone National Park (Takacs et al, 2001), and Thermocrinis ruber, the single representative of the genus Thermocrinis isolated from Octopus Spring, Yellowstone National Park (Huber et al, 1998).…”