Miroshnichenko Margarita L, Tourova Tatyana P, Kolganova Tatyana V, Kostrikina Nadezhda A, Chernych Nikolay, Bonch-Osmolovskaya Elizaveta A
Winogradsky Institute of Microbiology, Russian Academy of Sciences, Moscow, Russia.
Int J Syst Evol Microbiol. 2008 Dec;58(Pt 12):2935-8. doi: 10.1099/ijs.0.2008/000182-0.
A novel anaerobic, extremely thermophilic, facultatively chemolithoautotrophic bacterium designated strain SR(T) was isolated from a terrestrial hot spring in Kamchatka (Russia). The cells of the novel strain were spore-forming rods with a Gram-positive type of cell wall. The novel isolate grew at 60-82 degrees C (optimum 75 degrees C) and pH 6.0-7.5 (optimum 6.8). Molecular hydrogen and formate were used as electron donors. Thiosulfate, sulfate or elemental sulfur served as electron acceptors yielding hydrogen sulfide. No growth was observed on either substrate in the presence of nitrate as the electron acceptor. The G+C content of the DNA was 56.2 mol%. Phylogenetic analyses of the 16S rRNA gene showed that strain SR(T) was most closely related to Ammonifex degensii (96.4 % gene sequence similarity). However, the novel isolate possessed phenotypic characteristics that differed significantly from those of A. degensii, the only other recognized species of the genus Ammonifex. It is concluded that strain SR(T) (=DSM 19636(T)=VKM B-2461(T)) represents the type strain of a novel species of the genus Ammonifex, for which the name Ammonifex thiophilus sp. nov. is proposed. An emendation of the genus Ammonifex is proposed based on the phenotypic characteristics of the novel species.
从俄罗斯堪察加半岛的一个陆地温泉中分离出一株新的厌氧、极端嗜热、兼性化能自养细菌，命名为菌株SR(T)。该新菌株的细胞为产芽孢杆菌，具有革兰氏阳性细胞壁类型。该新分离株在60-82℃（最适温度75℃）和pH 6.0-7.5（最适pH 6.8）条件下生长。分子氢和甲酸用作电子供体。硫代硫酸盐、硫酸盐或元素硫用作电子受体，产生硫化氢。当以硝酸盐作为电子受体时，在任何一种底物上均未观察到生长。DNA的G+C含量为56.2 mol%。对16S rRNA基因的系统发育分析表明，菌株SR(T)与德氏氨氧化菌（基因序列相似性为96.4%）关系最为密切。然而，该新分离株具有与德氏氨氧化菌显著不同的表型特征，德氏氨氧化菌是氨氧化菌属中唯一另一个已被认可的物种。结论是，菌株SR(T)（=DSM 19636(T)=VKM B-2461(T)）代表氨氧化菌属一个新物种的模式菌株，为此提出新名称嗜硫氨氧化菌。基于该新物种的表型特征，对氨氧化菌属提出了修订。
