16S rRNA 基因克隆文库。 用限制性内切酶 Hae 芋对随机挑选的阳性克隆子进行酶切分型,分别得到 7 个和 8 个可操作分类单 元(Operational Taxonomic Units, OTUs) ,两文库覆盖率均大于 98% 。 BLAST 比对和系统发育分析表明赛里木湖全部克隆子归 属于泉古菌门(Crenarchaeota) ,97% 的克隆子与不同环境免培养氨氧化泉古菌有较高的序列相似性(>97%) 。 柴窝堡湖水古菌 归为 3 个门:Thaumarchaeota (81. 2%) 、广古菌门(Euryarchaeota) (13%) 和泉古菌门(Crenarchaeota) (5. 8%) ,81. 2% 的克隆子 与具有氮代谢功能的氨氧化古菌纯培养物具有较高的序列相似性(97%-98%) ,13% 的克隆子与已分离到的产甲烷古菌序列 同源性大于 97% 。 研究发现新疆微咸水湖可能存有大量新划分的古菌 Thaumarchaeota 门类群、可培养氨氧化及产甲烷古菌类 群,两典型微咸水湖泊中古菌类群多样性较低且群落组成差异大。

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Urumqi No.10 spring is located in the fracture zone of Willow ditch鄄Hongyanchi in southern Urumqi, and is one of the most important national key hydrological observation points. The spring water contains various geochemical elements, such as sulfide, methane, hydrogen, radon, sulfide, methane, carbon dioxide, helium, fluorine and mercury. Microbes living in the spring are intensely affected by hydro鄄geochemical changes caused by movements of the Earth忆s crust. The 24 solar terms, part of the Chinese traditional calendar, can accurately reflect changes in the Earth忆s climate, and the habitats of microorganisms also change with changes in the solar terms. In order to understand the changes in the structure of the bacterial community and diversity in Urumqi No.10 spring with the 24 solar terms, spring water samples collected during each period of the 24 solar terms were analyzed by T鄄RFLP, and CCA analysis combined with hydro鄄chemical analysis of indicators in the spring was conducted. Diversity analysis shows that the Shannon index (H) of the spring bacterial Proteobacteria Acidithiobacillus 165 Acidiphilium 441 Geobacter 130 Thiothrix 130 Fusobacteria Leptotrichia 165 Others Olavius 165 特殊类群 Particular Community Actinobacteria Microbacterium 165 Mycobacterium 165 Bacteroidetes Capnocytophaga 84 Cytophaga 84 Microscilla 93 Proteobacteria Achromatium 455 Azoarcus 84 Azospirillum 130 / 165 Caulobacter 130 Desulfatiferula 165 Desulfobacter 165 Desulfofrigus 165 Stenotrophomonas 455

Most methods for investigating bacterial diversity of soil microorganisms was lack of the ability to establish a causal relationship between function and community compositions. Recently, using stable isotopes to label phylogenetically informative biomolecules ( phospholipid fatty acids, DNA, or RNA ) , has the advantage of providing more definitive evidence that a detected population is active in a specific process, if that process leads to assimilation of C or N into cellular constituents. In practice, Nucleic acid SIP is considerably more sensitive and more informative for taxonomic purposes, particularly among of those related organisms, and thus is more generally useful.Shawan cold spring provides a typical non鄄sulfide cold spring environment in the arid and semi鄄arid areas of Xinjiang.In the previous research, the first overview of microbial diversity in the Shawan cold spring had provided, and the results showed that bacterial communities in the Shawan cold spring were diverse which comprised of 11 phyla and maybe exist a diversity of functional groups. In this paper, we surveyed the carbon sources utilization functional bacteria and their diversity in the sediment of the cold spring by stable isotope probing ( SIP) and 16S rDNA clone library. The functional bacteria were enriched using 13 C鄄labeled glucose as substrate, and then 13 C鄄labeled genomic DNA was separated directly from the sediment samples and then it used as template for the PCR amplification of bacterial 16S rRNA gene and http: / / www. ecologica. cn construction of the gene clone library. Based on restriction fragment length polymorphism ( RFLP ) , 417 positive clones were picked up and grouped into 27 operational taxonomic units ( OTUs) by Hae III digestion. Subsequently, unique clones were sequenced. The blast search in Genbank and phyogenetic sequence analysis showed that 27 OTUs were divided into 9 phyla of bacterial domain i. e. , Firmicutes, Chloroflexi, Nitrospirae, Actinobacteria, Proteobacteria, Bacteroidetes, Planctomycetes, Cyanobacteria and Acidobacteria. Of those, Firmicutes and Proteobacteria were the dominant groups, and accounted for 28. 3% and 38. 6% of the total clone library respectively.Compared with 86 OTUs in the previous publication, Gemmatimonadetes, Chlorobi and Verrucomicrobia were not captured in glucose鄄utilizing bacteria, and the number of OTUs in other phyla decreased evidently, especially in Acidobacteria, only 6. 45% of OTUs was observed in this research (48% in the previous research) . In sum, that only 31% OTUs utilized glucose as carbon source in the system, suggesting there maybe exist other carbon sources utilization bacteria in the environment. In addition, we found that the incubating time and substrate concentration are key factors for the detection of some species that in low lever in the environment. As the result of enriching in this paper, a lots of OTUs were detected for the first time, such as the phylum Chloroflexi and genus Desulfuromonas. Particularly, genusDesulfuromonas was an important sup...

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