Wagner Isaac D, Ahmed Sibtain, Zhao Weidong, Zhang Chuanlun L, Romanek Christopher S, Rohde Manfred, Wiegel Juergen
Department of Microbiology, University of Georgia, Athens, GA 30602-2605, USA.
Int J Syst Evol Microbiol. 2009 Nov;59(Pt 11):2685-91. doi: 10.1099/ijs.0.005207-0. Epub 2009 Jul 22.
An anaerobic thermophilic bacterium, designated strain JW/SA-NV4(T), was isolated from a xylan-supplemented enrichment culture from Trego hot spring located within the Black Rock Desert (NV, USA). Cells were generally straight or slightly bent rod-shaped, 0.4-0.8 microm in width and 3-6 microm in length during exponential growth. Cells from stationary phase were variable in size and shape, showing curved or bent morphology. Motility was not seen and flagella were not observed in electron micrographs. Sporulation was not observed. Strain JW/SA-NV4(T) stained Gram-negative but is phylogenetically Gram-type positive. Growth occurred at pH(25 degrees C) 6.8-8.8, with optimum growth at pH 8.4; no growth occurred at pH 9.0 or above or at 6.5 or below. With glucose or xylose as the carbon source, strain JW/SA-NV4(T) grew at 44-74 degrees C; no growth occurred at 76 degrees C or above or at 42 degrees C or below. However, the optimum temperature was 62 and 66 degrees C when grown on glucose and xylose, respectively. The shortest doubling time observed with glucose was approximately 4 h, and with xylose approximately 3.4 h. Strain JW/SA-NV4(T) tolerated an atmosphere containing up to 0.1 % O(2); no growth occurred at a gas atmosphere of 0.2 % O(2). Chemo-organotrophic growth occurred with xylose, glucose, mannose, xylan, pyruvate, fructose, ribose, Casamino acids, mannitol, tryptone, peptone, cellobiose and yeast extract. When grown in mineral media containing 1 g yeast extract l(-1) as an electron donor, thiosulfate and sulfur were reduced to sulfide. The G+C content of the DNA was 38.6 mol% (HPLC). 16S rRNA gene sequence analysis placed strain JW/SA-NV4(T) within the order Thermoanaerobacterales and within the Thermoanaerobacterales Incertae Sedis Family III, specifically between taxa classified within the genera Thermosediminibacter and Thermovenabulum. The closest phylogenetic neighbours were Thermosediminibacter oceani JW/IW-1228P(T) (94.2 % 16S rRNA gene sequence similarity) and Thermosediminibacter litoriperuensis JW/YJL-1230-7/2(T) (94.0 %) [Lee, Y.-J., Wagner, I. D., Brice, M. E., Kevbrin, V. V., Mills, G. L., Romanek, C. S. & Wiegel, J. (2005). Extremophiles 9, 375-383]. Based on physiological and genotypic characteristics, strain JW/SA-NV4(T) (=DSM 18802(T)=ATCC BAA-1454(T)) is proposed to represent the type strain of a novel species in a novel genus, Caldanaerovirga acetigignens gen. nov., sp. nov.
从美国内华达州黑岩沙漠特雷戈温泉中添加木聚糖的富集培养物中分离出一株厌氧嗜热细菌，命名为菌株JW/SA-NV4(T)。指数生长期的细胞通常为直杆状或稍弯曲的杆状，宽度为0.4 - 0.8微米，长度为3 - 6微米。稳定期的细胞大小和形状各异，呈现弯曲或弯折的形态。未观察到运动性，电子显微镜下也未发现鞭毛。未观察到芽孢形成。菌株JW/SA-NV4(T)革兰氏染色呈阴性，但在系统发育上属于革兰氏阳性类型。在pH值（25℃）6.8 - 8.8范围内生长，最适生长pH值为8.4；在pH值9.0及以上或6.5及以下不生长。以葡萄糖或木糖作为碳源时，菌株JW/SA-NV4(T)在44 - 74℃生长；在76℃及以上或42℃及以下不生长。然而，分别以葡萄糖和木糖为碳源生长时，最适温度分别为62℃和66℃。以葡萄糖培养时观察到的最短倍增时间约为4小时，以木糖培养时约为3.4小时。菌株JW/SA-NV4(T)能耐受高达0.1% O₂的气氛；在0.2% O₂的气体气氛中不生长。利用木糖、葡萄糖、甘露糖、木聚糖、丙酮酸、果糖、核糖、酪蛋白氨基酸、甘露醇、胰蛋白胨、蛋白胨、纤维二糖和酵母提取物进行化能有机营养生长。当在含有1 g酵母提取物l⁻¹作为电子供体的矿物培养基中生长时，硫代硫酸盐和硫被还原为硫化物。DNA的G+C含量为38.6 mol%（高效液相色谱法）。16S rRNA基因序列分析将菌株JW/SA-NV4(T)置于嗜热厌氧杆菌目内，属于嗜热厌氧杆菌目未定科III，具体位于分类在嗜热沉积杆菌属和嗜热脉管菌属之间的分类单元之间。最接近的系统发育邻居是海洋嗜热沉积杆菌JW/IW-1228P(T)（16S rRNA基因序列相似性为94.2%）和秘鲁海岸嗜热沉积杆菌JW/YJL-1230-7/2(T)（94.0%）[Lee, Y.-J., Wagner, I. D., Brice, M. E., Kevbrin, V. V., Mills, G. L., Romanek, C. S. & Wiegel, J. (2005). Extremophiles 9, 375 - 383]。基于生理和基因型特征，提议菌株JW/SA-NV4(T)（=DSM 18802(T)=ATCC BAA-1454(T)）代表一个新属嗜热产乙酸厌氧病毒属（Caldanaerovirga）中一个新物种嗜热产乙酸厌氧病毒（Caldanaerovirga acetigignens）的模式菌株。
