Published isolates

Nautilia sp. strain PV-1

Epsilonproteobacteria
In the picture - Electron micrograph of negatively stained Nautilia sp. strain PV-1 cells.

Nautilia sp. strain PV-1 is a piezophilic, thermophilic, anaerobic, chemolithoautotrophic bacterium isolated from a deep-sea hydrothermal vent on the East Pacific Rise. Cells were Gram-negative curved rods, and grew optimally at 60ºC and 20MPa. Chemolithoautotrophic growth occurred with H₂ as the energy source and CO₂ as the carbon source. Nitrate and sulfur were used as electron acceptors with production of ammonia and sulfide, respectively.

Varunaivibrio sulfuroxidans gen. nov. sp. nov.

Alphaproteobacteria
In the picture - Electron micrograph of negatively stained Varunaivibrio sulfuroxidans cells.

Varunaivibrio sulfuroxidans is a mesophilic, facultative anaerobic, facultative chemolithoautotrophic bacterium isolated from a sulfidic shallow-water marine gas vent located at Tor Caldara, in the Tyrrhenian Sea, Italy. Cells were Gram-negative curved rods, and grew optimally at 30ºC, 1.5% NaCl, and pH 6.0 - 7.0. Chemolithoautotrophic growth occurred with sulfur and thiosulfate as the electron donors, CO2 as the carbon source, and nitrate, oxygen (5% v/v) and ferric iron as the electron acceptors. The bacterium was also capable of chemoorganoheterotrophic and chemolithoherotrophic growth.

Sulfurovum riftiae sp. nov.

Epsilonproteobacteria
In the picture - Electron micrograph of a thin section of Sulfurovum riftiae cells.

Sulfurovum riftiae is a mesophilic, anaerobic chemosynthetic bacterium isolated from the tube of the vent polychaete, Riftia pachyptila on the East Pacific Rise. Cells were Gram-negative, and grew optimally at 35ºC, 3% NaCl, and pH 6.0. Growth occurred under chemolithoautotrophic conditions using sulfur or thiosulfate as the energy source and CO₂ as the carbon source. Nitrate was used as the sole electron acceptors.

Cetia pacifica gen. nov., sp. nov.

Epsilonproteobacteria
In the picture - Platinum-shadowed electron micrograph of Cetia pacifica cells.

Cetia pacifica is a thermophilic, anaerobic chemosynthetic bacterium isolated from an active deep-sea hydrothermal vent on the East Pacific Rise. Cells were Gram-negative, and grew optimally at 55ºC, 2-3% NaCl, and pH 4.5. Growth occurred under chemolithoautotrophic conditions using H₂ as the energy source and CO₂ as the carbon source. Nitrate and sulfur were used as electron acceptors with production of ammonia and sulfide, respectively.

Galenea microaerophila gen. nov. sp. nov.

Gammaproteobacteria
In the picture - Scanning electron micrograph of Galenea microaerophila cells during growth. Extracellular deposited elemental sulfur crystals are visible.

Galenea microaerophila is a mesophilic, strictly microaerophilic, chemosynthetic bacterium isolated from the sediment of an active shallow-water hydrothermal vent in Paleochori Bay, on the Greek island of Milos. The cells are Gram-staining-negative rods growing at 35ºC with 3% NaCl, pH 5.5, under chemolithoautotrophic conditions with thisulfate and CO₂ as the energy and carbon sources, respectively. Oxygen (5 %) is used as sole terminal electron acceptor.

Parvibaculum hydrocarbonoclasticum sp. nov.

Alphaproteobacteria
In the picture - Electron micrograph of a thin section of Parvibaculum hydrocarboniclasticum cells.

Parvibaculum hydrocarbonoclasticum is an aerobic, alkane-oxidizing bacterium isolated from hydrothermal fluids collected from a deep-sea vent on the East Pacific Rise. The cells were Gram-negative rods that showed optimal growth at 35ºC, 2.5% NaCl, and pH 7.5. Grow occurred aerobically in artificial seawater minimal medium with n-alkanes as sole carbon and energy sources, and also in artificial seawater medium supplemented with peptone and yeast extract.

Phorcysia thermohydrogeniphila gen. nov. sp. nov.

Aquificae
In the picture - Scanning electron micrograph of a biofilm formed by Phorcysia thermohydrogeniphila at the gas–liquid interphase.

Phorcysia thermohydrogeniphila is a hyperthermophilic, anaerobic chemolithotrophic bacterium isolated from a tube of an Alvinella pompejana tubeworm collected at the East Pacific Rise at 13N. The cells were Gram-negative rods, and exhibited optimal growth at 75ºC, 3% NaCl, and pH 6.0, under chemolithoautotrophic conditions. H₂ and CO₂ were used as the energy and carbon sources, while nitrate and sulfur were used as terminal electron acceptors.

Nautilia nitratireducens sp. nov.

Epsilonproteobacteria
In the picture - Platinum-shadowed electron micrograph of Nautilia nitratireducens cells showing polar flagella

Nautilia nitratireducens is a thermophilic, anaerobic chemosynthetic bacterium isolated from the walls of an active deep-sea hydrothermal vent chimney on the East Pacific Rise. Cells were Gram-negative, and grew optimally at 55ºC, 2% NaCl, and pH 7.0. Growth occurred under chemolithoautotrophic conditions using H₂ as the energy source and CO₂ as the carbon source. Nitrate, thiosulfate, sulfur and selenate were used as electron acceptors. Chemo-organotrophic growth occurred in the presence of acetate, formate, casamino acids, sucrose, galactose and yeast extract.

Salinisphaera hydrothermalis sp. nov.

Gammaproteobacteria
In the picture - Platinum-shadowed electron micrograph of Salinisphaera hydrothermalis cells.

Salinisphaera hydrothermalis is a mesophilic, aerobic, facultative chemolithoautotrophic bacterium isolated from hydrothermal fluids from a diffuse flow vent on the East Pacific Rise at 9N. Cells were Gram-negative, and grew optimally at 30-35ºC, 2.5% NaCl, and pH 5.5. Growth occurred under aerobic chemolithoautotrophic conditions in the presence of thiosulfate and CO₂, under heterotrophic conditions with acetate or n-alkanes as sole carbon and energy sources and in complex Artificial Seawater (ASW) medium.

Caminibacter mediatlanticus sp. nov.

Epsilonproteobacteria
In the picture - Electron micrograph of a thin section of Caminibacter mediatlanticus cells.

Caminibacter mediatlanticus is a thermophilic, anaerobic chemosynthetic bacterium isolated from an active deep-sea hydrothermal vent at Rainbow, on the Mid-Atlantic Ridge. Cells were Gram-negative, and grew optimally at 55ºC, 3% NaCl, and pH 5.5. Growth occurred under chemolithoautotrophic conditions using H₂ as the energy source and CO₂ as the carbon source. Nitrate and sulfur were used as electron acceptors with production of ammonia and sulfide, respectively.

Thermovibrio ammonificans sp. nov.

Aquificae
In the picture - Electron micrograph of a thin section of Thermovibrio ammonificans cells.

Thermovibrio ammonificans is a hyperthermophilic, anaerobic chemolithotrophic bacterium isolated from the walls of an active deep-sea hydrothermal vent chimney on the East Pacific Rise. The cells were Gram-negative rods, and exhibited optimal growth at 75ºC, 2% NaCl, and pH 5.5, under chemolithoautotrophic conditions. H₂ and CO₂ were used as the energy and carbon sources, while nitrate and sulfur were used as terminal electron acceptors.