Venenivibrio stagnispumantis

Taxobox
color = lightgrey


image_size = 180px
image_caption = Scanning electron microscopy image
name = Strain CP.B2
domain = Bacteria
phylum = Aquificae
classis = Aquificae
ordo = Aquificales
familia = Hydrogenothermaceae
genus = "Venenivibrio"
species = "V. stagnispumantis"
binomial = "Venenivibrio stagnispumantis"
binomial_authority = Hetzer et al. 2008

"Venenivibrio stagnispumantis" strain CP.B2 is the first microorganisms isolated from the terrestrial hot spring Champagne Pool (75°C, pH 5.5) in Waiotapu, New Zealand [Hetzer, A., Morgan, H. W., McDonald, I. R. & Daughney, C. J. (2007). [http://www.ncbi.nlm.nih.gov/pubmed/17426919 Microbial life in Champagne Pool, a geothermal spring in Waiotapu, New Zealand] . Extremophiles 11, 605-614.] [Hetzer, A., McDonald, I. R. & Morgan, H. W. (2008). [http://www.ncbi.nlm.nih.gov/pubmed/18218938 Venenivibrio stagnispumantis gen. nov., sp. nov., a thermophilic hydrogen-oxidizing bacterium isolated from Champagne Pool, Waiotapu, New Zealand] . International Journal of Systematic and Evolutionary Microbiology 58, 398-403.] .

Morphology

The cells are motile and slightly curved rods (1.04 to 1.56 µm long and 0.33 to 0.41 µm wide).

Growth conditions

The novel bacterium is an obligate chemolithotroph capable of utilizing H₂ as electron donor, O₂ as corresponding electron acceptor and CO₂ as carbon source. "Venenivibrio stagnispumantis" gains metabolic energy using the "Knallgas" reaction H₂ + ½ O₂ → H₂O. For growth either elemental sulphur (S⁰) or thiosulfate (S₂O₃²⁻) is required. Growth is observed under thermophilic conditions between 45°C and 75°C (optimum 70°C), under moderate acidophilic conditions between pH 4.8 and 5.8 (optimum pH 5.4) and under microaerophilic conditions between 1.0% and 10.0% (v/v) O₂ (optimum between 4.0% and 8.0% (v/v) O₂).

Phylogeny

Phylogenetic analysis based on 16S rDNA sequences indicate that strain CP.B2 belongs to the order "Aquificales" and represents the type strain of a novel species of a new genus within the family "Hydrogenothermaceae". The 16S rRNA gene sequence for strain CP.B2 is deposited in the GenBank nucleotide sequence database under accession number DQ989208. The G+C content of the genomic DNA is 29.3 mol% which is the lowest G+C content reported for a species of the order "Aquificales".

Tolerance to arsenic and antimony compounds

"Venenivibrio stagnispumantis" displays tolerance to relatively high concentrations of arsenic and antimony compounds. Cells grew in the presence of up to 8 mM arsenite (As³⁺), 15 mM trivalent antimony (Sb³⁺), and >20 mM arsenate (As⁵⁺) but growth was not observed when As³⁺ and As⁵⁺ were provided as the sole electron donor and acceptor pair.

Nomenclature

Ve.ne.ni.vi' bri.o. (Latin: the vibrio of poison) stag.ni.spu.man' tis. (Latin: from the bubbling pool, pertaining to Champagne Pool).

Culture collection

"Venenivibrio stagnispumantis" strain CP.B2 is deposited in the Japan Collection of Microorganisms under JCM 14244 and in the German Collection of Microorganisms under DSM 18763.

Culture medium

The pH of the medium is adjusted to 5.5, distrubted into culture vessels and autoclaved under CO₂. After the inoculation the initial gas phase is replaced with H₂ / CO₂ / O₂ (79% / 15% / 6%) and pressurized to 170 kPa.

The pH of the solution is adjusted to 3.0 with HCl.

References