Caldwell D E, Caldwell S J, Laycock J P
Can J Microbiol. 1976 Oct;22(10):1509-17. doi: 10.1139/m76-223.
Thermothrix thioparus gen. et ep. nov. occurs naturally in a New Mexico hot spring at a temperature of 74 degrees C, a pH of 7.0, and a HS- concentration of 1 mg/litre. The organism is gram-negative, non-motile, 0.5-1.0 X 3-20 mum, and forms cell chains up to 1 cm in length. The resulting filaments do not possess a sheath. Sulfur is deposited extracellularly. The organism was isolated using an autotrophic medium with HS- as the energy source and NO3- as the terminal electron acceptor. Anaerobically either NO2- or NO3- is required, NO2- is formed from NO3-, and no observable gas is evolved. Oxygen can also be used as the terminal electron acceptor, but growth is poor because of the decreased solubility of O2 at temperatures required for growth. Alternate energy sources used aerobically and anaerobically include hexose, HS-, SO3-, and S2O3=. The temperature optimum is 70-73 degrees C and growth occurs from 62 to 77 degrees C. The organism's thermal and physiological characteristics are compared to those of Bacillus stearothermophilus, Methanobacterium thermoautotrophicum, Sulfolobus acidocalderius, Thermus aquaticus, Thermus flavus, as well as Thiobacillus denitrificans, the latter being the only other facultatively anaerobic chemolithotroph which has been isolated and described.
嗜热硫丝菌属新属及新种（Thermothrix thioparus gen. et sp. nov.）自然存在于新墨西哥州的一个温泉中，该温泉温度为74摄氏度，pH值为7.0，硫化氢（HS⁻）浓度为1毫克/升。该生物体为革兰氏阴性菌，无运动性，大小为0.5 - 1.0×3 - 20微米，可形成长度达1厘米的细胞链。形成的丝状体不具有鞘。硫在细胞外沉积。该生物体是使用以HS⁻作为能源、硝酸根离子（NO₃⁻）作为末端电子受体的自养培养基分离得到的。在厌氧条件下，需要亚硝酸根离子（NO₂⁻）或硝酸根离子，硝酸根离子会形成亚硝酸根离子，且无明显气体产生。氧气也可用作末端电子受体，但由于在生长所需温度下氧气溶解度降低，生长较差。有氧和厌氧条件下使用的替代能源包括己糖、HS⁻、亚硫酸根离子（SO₃⁻）和硫代硫酸根离子（S₂O₃²⁻）。最适温度为70 - 73摄氏度，生长温度范围为62至77摄氏度。将该生物体的热学和生理学特征与嗜热脂肪芽孢杆菌（Bacillus stearothermophilus）、嗜热自养甲烷杆菌（Methanobacterium thermoautotrophicum）、嗜酸热硫化叶菌（Sulfolobus acidocalderius）、嗜热水栖热菌（Thermus aquaticus）、嗜热黄栖热菌（Thermus flavus）以及反硝化硫杆菌（Thiobacillus denitrificans）进行了比较，后者是唯一已被分离和描述的另一种兼性厌氧化能自养菌。
