先锋生物地嗜皮菌科放线菌多样性及其生态功能研究

Actinobacteria from extreme environments have already become the hot topic owing to them as the ideal resource for novel drug research and development. Among which, partial pioneer microorganisms play a key role in soil formation, improvement and keep its sustainable utilization in extreme environments, such as deserts and dry-hot valleys, which is of significance and great application value in research of resistance-hardiness mechanism, desert control and environmental restoration. Therefore, it is not only the general trend of our times in practice the concept of technology innovation and sustainable development, but also the responsibility of the pursuit of scientific researchers, to pay close attention to the diversity and ecological function of the pioneer microbes and carry out the related research in depth. This project is to focus on exploration the diversity of the pioneer microbes of Geodermatophilaceae and discovery of the valuable Geodermatophilaceae resources based on our previous research results of the actinobacteria from Shapotou desert. Culture-dependent and metagenomic sequencing analysis techniques will be employed here. The specific strains will be chosen to be tested their biologic characteristics, genome information and their metabolites, to explore the specific metabolites and to discover the novel genes from Geodermatophilaceae; and to elucidate the relationship between the resistance-hardiness characteristics and genes, and between metabolites and genes of actinobacteria. As a result, the mechanism of the Geodermatophilaceae in the rock weathering process and desert biological crusts formation is to be elucidated based on the comparative analysis of spatial distribution and ecological function of the Geodermatophilaceae members.

极端生境放线菌作为新药研发的理想资源早已备受关注。部分先锋微生物在沙漠、干热河谷等极端环境土壤的形成、改良和维持其可持续利用中也起着关键性的作用，在抗逆机制研究、沙漠治理、环境修复等方面有重要的研究和应用价值。因此，深入关注和开展先锋微生物的多样性和生态功能研究，既是践行创新、绿色发展理念的时代大势所趋，也是科研工作者的责任追求。本项目拟以我们前期对沙坡头沙漠环境放线菌资源的探索为基础，聚焦于地嗜皮菌科放线菌这类先锋生物，综合纯培养和宏基因组信息分析结果，探测地嗜皮菌科放线菌的多样性，发掘优质资源放线菌；结合特色菌株的生物学特性、基因组和代谢产物分析，探寻地嗜皮菌科放线菌的特有代谢产物，发现优秀的基因新资源；并揭示放线菌抗逆特性和基因之间、以及次级代谢产物与基因之间的关系；通过对比分析菌株的时空分布特征和生态功能，阐明地嗜皮菌科放线菌在岩石风化过程中和沙漠生物结皮形成过程中的作用机制。

先锋微生物在沙漠、干热河谷等极端环境土壤的形成、改良以及维持其可持续利用中起着关键性的作用，在抗逆机制研究、沙漠治理、环境修复等方面有重要的研究和应用价值。深入开展先锋微生物的多样性和生态功能研究，既是践行创新、绿色发展理念的时代大势所趋，也是科研工作者的责任所在。.本项目聚焦于沙漠环境先锋微生物地嗜皮菌科放线菌的多样性及其生态功能研究，旨在为微生物资源的发掘开辟新路径。.首先，通过高通量测序手段，对比分析了水环境、陆地土壤生境和沙漠环境微生物群落结构特征，着重探测了腾格里沙漠、巴丹吉林沙漠和古尔班通古特沙漠等不同沙漠来源的多个微生态环境样品中的放线菌群落结构特点，发现：1）地嗜皮菌科放线菌是沙漠环境的广布微生物，其在沙漠环境的多样性和丰度远高于其他生境；2）地嗜皮菌科放线菌的多样性和丰富度与沙漠微生态环境有一定的关联性。.以宏基因组测序分析结果为指导，优化了放线菌分离培养方案，从上述多种生态环境收集了1929株环境特色资源菌，其中460株是地嗜皮菌科放线菌纯培养物（这些菌株覆盖了地嗜皮菌科的大多数分类单元），并从中发现13个新分类单元（3个新属，10个新物种）。通过对28株代表菌株的基因组序列分析，以及其对碳、氮、磷、硫的同化能力等方面的表型实验，从基因层面和代谢通路的角度探测了地嗜皮菌科放线菌的对多样化底物同化能力的遗传基础和生理特征。.以上结果揭示了地嗜皮菌科放线菌的生物多样性和生态多样性；初步确证地嗜皮菌科放线菌在沙漠环境中的生态功能核心地位，即维持微生物群落的稳定及其对碳、氮、磷、硫循环的重要贡献。