俄罗斯堪察加地区热泉及其周边生境的泉古菌多样性

Diversity of Crenarchaeota in terrestrial hot springs and their surrounding environments in Kamchatka,Russia

【目的】泉古菌为陆地热泉系统的主要古菌类群,可能在自然界生源元素的地球化学循环中发挥着重要作用。本研究旨在揭示俄罗斯堪察加地区热泉以及热泉周边区域的泉古菌多样性,同时基于之前已获得的我国云南地区热泉数据,比较两地区泉古菌群落差异。【方法】通过构建16S rRNA基因片段克隆文库获得序列信息和丰度,随后进行物种多样性、系统发育和群落结构差异分析。【结果】高温热泉Burlyashi Liza(BSL,89℃)中的泉古菌全部属于热变形菌纲(Thermoprotei)内的物种。中温热泉TF Vent 2(TFV,49℃)的群落结构主要由不确定的热变形菌纲类群、不确定的泉古菌类群、高温水环境泉古菌类群Ⅱ(HWCG-Ⅱ)和奇古菌下的Group1.1b类群组成。热泉周边常温环境的主要物种与热泉环境的代表性克隆pJP41一起聚成一个较大的遗传分枝。Jackknife聚类树和主坐标分析(Principal coordinates analysis,PCoA)的结果显示:温度相似的样点,其泉古菌群落结构相对来说更为相似。【结论】俄罗斯堪察加地区与我国云南地区热泉中的泉古菌存在着一定程度上的不同。陆地热泉系统影响着其周边环境的泉古菌类群。热泉中泉古菌群落结构受温度的明显影响。

[Objective] Crenarchaeota is a major archaeal lineage in terrestrial hot springs and important in biogeochemical cycles of life-essential elements.In this study,we investigated the diversity of Crenarchaeota in hot springs and the surrounding environments in Kamchatka,Russia.In addition,we compared crenarchaeotal community structures in Kamchatka,Russia and Yunnan province,China.[Methods] Crenarchaeal 16S rRNA gene clone libraries were constructed and the sequences and abundances of representational clone were obtained.Phylogenetic analysis was then performed and the community structures in different samples were compared.[Results] The high temperature spring Burlyashi Liza（BSL,89℃） comprised Thermoprotei.The moderate temperature spring TF Vent 2（TFV,49℃） harbored unidentified Thermoprotei group,unidentified crenarchaeal group,HWCG-II（hot water crenarchaeotal group II）,and Group1.1b（one thaumarchaeotal subgroup）.Most of sequences that obtained from surrounding environments（15℃） are closely with the representational clone pJP from a Yellowstone hot spring.Jackknife cluster and Principal coordinates analysis（PCoA） showed that the samples have more similarity in crenarchaeal communities at similar temperatures.[Conclusion] The diversities of Crenarchaeota in Kamchatka hot springs are somewhat different from those in Yunnan province.Terrestrial hot springs obviously affect the crenarchaeotal communities in surrounding environments.Temperature is the major factor controlling the community structure in terrestrial hot springs.