云南腾冲热泉极端嗜酸热硫化叶菌多样性研究

Diversity of Thermoacidophilic Sulfolobus in Hot Springs in Tengchong of Yunnan,China

硫化叶菌(Sulfolobus)是极端嗜热古菌遗传机制研究的重要模式菌株,广泛分布于酸性热泉中.对分离自云南腾冲酸性热泉的11株极端嗜酸热菌株进行16S rRNA基因序列测定,并通过菌体形态观察、16S rRNA基因可变区序列比较、菌株16S rRNA基因相似性比较及系统发育分析,研究腾冲热泉硫化叶菌的多样性.结果表明,分离自腾冲热泉的11株硫化叶菌的16S rRNA基因序列与分离自世界上其它地区的8个硫化叶菌的标准菌株的相似性为85.8%～94.9%,与同样分离自腾冲热泉的S.tengchongensis标准菌株的相似性为96.6%～97.5%,在分类学上具有形成新种的可能.在16S rRNA基因高可变区序列上,与分离自世界上其它地区的8个硫化叶菌的标准菌株存在明显的差异.系统发育分析表明,分离自腾冲热泉的硫化叶菌在系统发育树上形成两个亲缘关系较为紧密的簇群,可见腾冲热泉硫化叶菌不仅具有一定的多样性,同时具有较明显的地域性特征.

The strains of Sulfolobus are regarded as model organisms for investigating the inheritance mechanism of thermophilic archaea.These strains are widely distributed in acidic hot springs around the world.In this research,eleven thermoacidophilic strains isolated from six acidic hot springs in Tengchong of Yunnan,China were identified by analysis of their 16S rRNA gene sequences.Besides,their morphological characteristics of cells,16S rRNA gene hypervariable region sequences,16S rRNA gene similarity and phylogene were compared to explore the diversity of Sulfolobus distrubuted in Tengchong.The results showed that the 16S rRNA gene sequences of the eleven Sulfolobus strains had 85.8%～94.9% similarity to those of the eight Sulfolobus type strains from other regions,and 96.6%～97.5% to that of S.tengchongensis type strains.Thus,the eleven strains should belong to the genus Sulfolobus and would represent one novel species of Sulfolobus.Hypervariable region sequences comparison indicated that the 16S rRNA gene from Tengchong geothermal area have unique characteristics.Phylogenetic analysis also showed that the 16S rRNA gene from Tengchong geothermal area formed two clusters of closer relationship on the phylogenetic tree.This research results revealed the diversity of Sulfolobus strains and their distribution in Tengchong geothermal area.