In this thesis, we have isolated a strain of hyperthermophilic archaeon─ TA from Geothermal Valley in Bei Tou district, Taipei city, located in Northern Taiwan. The cell width ranges between 0.5 and 2.0μm, depending on the culture condition. This hyperthermophile is found to be single cells in liquid culture. It is shaped like an irregular sphere, with no flagellum and no mobility. It is Gram-negative and grows facultatively in both anaerobic and aerobic conditions. This organism is extremely thermophilic with guanine-plus cytosine (G + C) ratio of 31 mol %. Its optimal growth temperatures is 85 degree C and its optimal pH of growth is 3.0. They still thrive in the temperature range of from 60℃ to 95℃ and pH range of from 2.0 to 6.0. Although they were isolated in hot spring, they still could grow in the presence of 0.1 to 4 % NaCl. There are no growth when they were placed below pH 1.5 or above pH 6.0. It could maintain its reproductive ability under 37 degree C slowly.
