印度尼西亚Padang Cermin热泉古菌多样性分析

Phylogenetic Diversity of Archaeal Community in the Hot Spring in Padang Cermin,Sumatra,Indonesia

通过印度尼西亚苏门答腊岛Padang Cermin热泉环境基因组DNA构建古菌16SrRNA基因文库,并利用PCR-RFLP技术对其古菌多样性和系统发育分析进行了研究。根据限制性内切酶AluⅠ和MspⅠ的特征性酶切图谱,将62个阳性克隆归类为14个分类操作单位(operational taxonomic unit,OTU),文库的覆盖度达90.32%。克隆文库的优势类群为OTU2和OTU1,分别占克隆文库的27.42%和20.96%。从每个OUT中选取一个代表性克隆进行16SrRNA基因的序列测定与系统发育分析,结果表明,测定的Padang Cermin热泉中的古菌均属于泉古菌门,包括热变形菌目(Thermoproteales)、硫还原球菌目(Desulfurococcales)、杂色泉古菌(miscellaneous crenar-chaeotic group,MCG)和未培养泉古菌(uncultured Crenarchaeota,UC),该热泉代表性克隆与GenBank数据库已有16SrRNA序列的相似性为91.9%～97.8%,而且与其相似性最高的序列均来自未培养的古菌克隆,由结果可见,Padang Cermin热泉古菌群落与已报道的其他热泉古菌群落的相似性较低,表明该热泉可能具有某些独特的特征,存在着特殊的古菌生态类群。

Diversity and phylogenetic analysis of archaea in the hot spring in Padang Cermin, Sumatra, In- donesia are investigated by constructing the 16S rRNA gene library of metagenomic DNA and using PCR- RFLP technique. Total 62 positive clones are classified into 14 operational taxonomic units （OTUs） ac- cording to their distinct restriction patterns of two kinds of restriction enzymes Alu I and Msp I ~ A rep- resentative clone from each OTU is sequenced. The phylogenetic analysis shows that all archaea in the hot spring in Padang Certain belong to Crenarchaeota, including Thermoproteales, Desulfurococcales, miscel- laneous crenarchaeotic group （MCG） and some unidentified families. The similarities between the repre- sentative clone sequences from the hot spring in Padang Cermin and their closest sequences deposited in GenBank range from 91.9% to 97.8% and all of the closest matches are from uncultured archaeal clones. Comparing with those reported in other hot springs of the world, the lower similarity of uncultivable clones indicate that the archaea in the hot spring in Padang Certain might have some unique characters, probably being the presence of a particular archaeal community.