Odintsova E V, Jannasch H W, Mamone J A, Langworthy T A
Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543, USA.
Int J Syst Bacteriol. 1996 Apr;46(2):422-8. doi: 10.1099/00207713-46-2-422.
A new aerobic, obligately chemolithoautotrophic, thermophilic, sulfur-oxidizing bacterium, Thermothrix azorensis, was isolated from a hot spring on Sao Miguel Island in the Azores. The cells of this organism are gram negative, nonsporulating, and rod shaped. Filament formation appears to occur as a response to nonoptimal growth conditions. Growth occurs at 63 to 86 degrees C, and the optimum temperature is 76 to 78 degrees C. The optimum pH range for growth is 7.0 to 7.5. The G+C content of the DNA of our isolate is 39.7 mol%. This isolate uses thiosulfate, tetrathionate, hydrogen sulfide, and elemental sulfur as energy sources. Of particular interest are the absence of Calvin cycle enzymes and the initial appearance of sulfide during the lag phase of growth of aerobic cultures grown on elemental sulfur. The subsequent formation of thiosulfate is followed by oxidation of the thiosulfate to sulfate. T. azorensis differs from the only other Thermothrix species that has been described, Thermothrix thiopara, by having higher optimum and maximum growth temperatures, by being an obligate chemolithoautotroph, and by its close but separate position on a 16S rRNA sequence-based phylogenetic tree. Our T. azorensis isolate has been deposited in the American Type Culture Collection as strain ATCC 51754T (T = type strain).
从亚速尔群岛圣米格尔岛的一处温泉中分离出一种新的需氧、专性化能无机自养嗜热硫氧化细菌——阿佐尔热丝菌。该生物体的细胞革兰氏阴性、不产芽孢、呈杆状。丝状形成似乎是对非最适生长条件的一种反应。生长温度为63至86摄氏度，最适温度为76至78摄氏度。生长的最适pH范围是7.0至7.5。我们分离株的DNA的G+C含量为39.7摩尔%。该分离株利用硫代硫酸盐、连四硫酸盐、硫化氢和元素硫作为能源。特别令人感兴趣的是，在以元素硫为培养基的需氧培养物生长的延迟期，卡尔文循环酶缺失，且最初出现硫化物。随后形成硫代硫酸盐，接着硫代硫酸盐被氧化为硫酸盐。阿佐尔热丝菌与已描述的另一种热丝菌——嗜硫热丝菌不同，其最适和最高生长温度更高，是专性化能无机自养菌，并且在基于16S rRNA序列的系统发育树上处于相近但独立的位置。我们的阿佐尔热丝菌分离株已作为ATCC 51754T菌株（T = 模式菌株）保藏于美国典型培养物保藏中心。
