Birrien J.-L.,CNRS Lab for Microbiology of Extreme Environments |
Birrien J.-L.,Universiteeuropeenne Of Bretagne Ueb |
Zeng X.,CNRS Lab for Microbiology of Extreme Environments |
Zeng X.,Xiamen University |
And 12 more authors.
International Journal of Systematic and Evolutionary Microbiology | Year: 2011
An obligate piezophilic anaerobic hyperthermophilic archaeon, designated strain CH1T, was isolated from a hydrothermal vent site named 'Ashadze', which is located on the Mid-Atlantic Ridge at a depth of 4100 m. Enrichment and isolation of the strain were carried out at 95oC under a hydrostatic pressure of 42 MPa. Cells of strain CH1T were highly motile irregular cocci with a diameter of ~1-1.5 μm. Growth was recorded at 80-108 °C (optimum 98 oC) and at pressures of 20-120 MPa (optimum 52 MPa). No growth was observed under atmospheric pressures at 60-110 oC. Growth was observed at pH 6.0-9.5 (optimum 7.5-8.0) and in 2.5-5.5% (w/v) NaCl (optimum 3.5%). Strain CH1T was strictly anaerobic and grew on complex proteinaceous substrates, such as yeast extract, Peptone, and casein, as well as on sucrose, starch, chitin, pyruvate, acetate and glycerol without electron acceptors. The G+C content of the genomic DNA was 49.0±0.5 mol%. Analysis of 16S rRNA gene sequences revealed that strain CH1T belongs to the genus Pyrococcus. Based on its physiological properties and similarity levels between ribosomal proteins, strain CH1T represents a novel species, for which the name Pyrococcus yayanosii sp. nov. is proposed. The type strain is CH1T (5JCM 16557). This strain is also available by request from the Souchotheque de Bretagne (catalogue LMBE) culture collection (collection no. 3310). © 2011 IUMS.