一株产甲烷菌的生物学特性及系统发育分析的研究

Biological Characteristic and Phylogenetic Analysis of Methanogen from the West of Yahu Lake

采用严格的亨盖特（hungate）厌养技术，从青海湖鸭湖西端沉积物中富集分离得到MQ-4菌株．MQ-4菌株为革兰氏阴性菌、不运动、球状、直径1μm左右．菌落圆形，从无色透明到黄色．该菌能利用甲酸钠及H2/CO2产甲烷．最适生长温度35-40℃，最适pH7．0，最适盐浓度4％．对MQ-4菌株进行16S rDNA的PCR扩增，测序并对序列进行分析，构建系统发育树，表明菌株MQ-4属于甲烷袋状菌属．

A strain of methanogenic bacterium MQ-4 was isolated form the sediments of the west of yahu lake by Hungate roll-tube techhique. Cells of MQ-4 are Gram negative, nonmotile and coccoids （average diameter, 1 μm）. Colony is transparence or yellow, roughly round. MQ-4 uses H2/CO2 or formate as substrates for CH4 formation. The strain grows best at pH values near 7.0, and Na^＋ concentration of 670mmol/L, the optimal growth temperature is 35 -40℃. On the basis of physiology, morphology and phylogenetic anlysis, the strain MQ-4 is considered of belonging to the genus of Methanocullues.