A strictly anaerobic, dissimilatory Fe(III)-reducing hyperthermophilic archaeon, designated as strain IOH1^T, was isolated from a new deep-sea hydrothermal vent (Onnuri Vent Field) area in the Central Indian Ocean ridge. Strain IOH1^T showed > 99% 16S rRNA gene sequence similarity with Thermococcus celericrescens TS2^T (99.4%) and T. siculi DSM 12349^T (99.2%). Additional three species T. barossii SHCK-94^T (99.0%), T. celer Vu13^T (98.8%), and ^{T. piezophilus} (98.6%) showed > 98.6% of 16S rRNA gene sequence similarity, however, the maximum OrthoANI value is 89.8% for the genome of T. celericrescens TS2^T. Strain IOH1^T cells are coccoid, 1.2–1.8 μm in diameter, and motile by flagella. Growth was at 70–82°C (optimum 80°C), pH 5.4–8.0 (optimum pH 6.0) with 2–4% (optimum 3%) NaCl. Growth of strain IOH1T was enhanced by starch, pyruvate, D(+)-maltose and maltodextrin as a carbon sources, and elemental sulfur as an electron acceptor; clearly different from those of related species T. celecrescens DSM 17994^T and T. siculi DSM 12349^T. Strain IOH1^T, T. celercrescence DSM 17994^T, and T. siculi DSM 12349^T reduced soluble Fe(III)-citrate present in the medium, whereas the amount of total cellular proteins increased with the concomitant accumulation of Fe(II). We determined a circular chromosome of 2,234 kb with an extra-chromosomal archaeal plasmid, pTI1, of 7.7 kb and predicted 2,425 genes. The DNA G + C content was 54.9 mol%. Based on physiological properties, phylogenetic, and genome analysis, we proposed that strain IOH1^T (= KCTC 15844^T = JCM 39077^T) is assigned to a new species in the genus Thermococcus and named Thermococcus indicus sp. nov.

中文翻译：

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印度热球菌 nov。，一种从中印度洋洋脊的Onnuri通风孔田野中分离出的还原Fe（III）的超高温古细菌。

一个严格厌氧，异化Fe（III）还原热古细菌，命名为菌株IOH1^牛逼，从一个新的深海热液喷口（Onnuri喷口区），面积在印度洋脊隔离。菌株IOH1 ^T显示与芹菜热球菌TS2 ^T（99.4％）和细圆线虫DSM 12349 ^T（99.2％）的> 99％的16S rRNA基因序列相似性。另外三个物种T. barossii SHCK-94 ^Ť（99.0％），T. CELER Vu13 ^Ť（98.8％），和^{T. piezophilus}（98.6％）表现出> 98.6％的16S rRNA基因序列相似性，但是，芹菜丁香TS2 ^T基因组的最大OrthoANI值为89.8％。菌株IOH1 ^T细胞呈球状，直径1.2–1.8μm ，能被鞭毛游动。生长在70–82°C（最佳80°C），pH 5.4–8.0（最佳pH 6.0）和2-4％（最佳3％）NaCl的条件下。淀粉，丙酮酸，D（+）-麦芽糖和麦芽糊精为碳源，元素硫为电子受体，促进了菌株IOH1T的生长。从这些相关物种的明显不同T. celecrescens DSM 17994 ^Ť和T. siculi DSM 12349 ^Ť。菌株IOH1 ^T，T.DSM 17994 ^T和T. siculi DSM 12349 ^T还原了培养基中存在的可溶性柠檬酸Fe（III），而总细胞蛋白的量随Fe（II）的积累而增加。我们确定了一个2234 kb的圆染色体，带有7.7 kb的染色体外古细菌质粒pTI1，并预测了2425个基因。DNA G + C含量为54.9mol％。基于生理特性，系统发育和基因组分析，我们提出将菌株IOH1 ^T（= KCTC 15844 ^T = JCM 39077 ^T）分配给Thermococcus属中的一个新物种，并将其命名为Thermococcus indicus sp。十一月