Thermococcus gammatolerans EJ3

Thermococcus gammatolerans (strain DSM 15229 / JCM 11827 / EJ3) is an obligatory anaerobic heterotrophic hyperthermophilic archaeon isolated from samples collected from hydrothermal chimneys located in the mid-Atlantic Ridge and at the Guyamas basin. T. gammatolerans is obtained by culture enrichment after irradiation with gamma rays at massive doses (30 kGy). It grows optimally at 88 degrees Celsius in the presence of sulfur or cystine on yeast extract, tryptone and peptone, producing H2S. This organism withstands 5 kGy of radiation without any detectable lethality. Exposure to higher doses slightly reduces its viability whereas cell survival of other thermophilic radioresistant archaea drastically decreases when cells are exposed to such radiation doses. Based on these data, T. gammatolerans is one of the most radioresistant archaeon isolated and characterized thus far. An important feature of the T. gammatolerans genome is the absence of genes encoding transposases found in other Archaea, indicating they are not played a role in the evolution of the Thermococcus genomes. The genome of T. gammatolerans contains two virus-related regions, tgv1 (20,832 bp) and tgv2 (20,418 bp). Even if T. gammatolerans is grown with peptides and S, numerous metabolic pathways appear to be active, including those involved in sugar catabolism and amino acid metabolism. (Adaptated from PMID:19558674). (HAMAP: THEGJ)