贵州典型喀斯特洞穴可培养放线菌多样性及其抗菌活性的研究

发布时间：2018-10-11 15:50

【摘要】：我国喀斯特洞穴的资源相对丰富,然而国内对洞穴微生物资源的研究还处于探索初步阶段。本课题研究主要运用纯培养方法,对中国贵州兴义和荔波两个地区喀斯特洞穴放线菌资源的多样性及其分布进行研究,并对分离到的放线菌菌株进行抗菌活性检测,以期从中挖掘新颖的活性产物。实验选取贵州地区喀斯特洞穴环境中不同类型样品为研究材料,通过利用多种分离培养基,共分离纯化得到458株放线菌。根据放线菌形态特征初步归纳后,对分离到的458菌株进行初步鉴定,结果发现:分离菌株分布于放线菌门放线菌纲下11个目22个科44个属,共193个种;通过16SrRNA基因序列比对,相似性低于98.5%的潜在新种15个。小单孢菌属(Micromonospora)、红球菌属(Rhodococcus)、微杆菌属(Microbacterium)、链霉菌属(Streptomyces)和类诺卡氏菌属(Nocardioides)为主要分布群体,而小月菌属、动球菌属、厄氏菌属、大理石雕菌属等稀有类群也有分布。对分离获得的218株放线菌菌株进行抗菌活性初筛。结果显示,在这81株活性菌株中有16株对设定的10种指示菌都有抑菌活性,表现出很强的抑制作用。有46株至少对3种以上的指示菌有抑菌作用。在这些活性菌株中,表现出较强抗菌活性的菌株多数为链霉菌,小单孢菌,在其它类群中也有分布。结果表明,喀斯特洞穴放线菌资源蕴藏着巨大的活性天然产物开发与应用潜力。选取三株潜在新分类单元YIMA1136T,YIMA1135T和SYSUK10001T进行了形态学、生理生化检测、化学组分分析、DNA同源性检测和系统进化分析的分类研究,确定了3个新种的分类地位,将其命名为Nocardioides cavernae,Nocardia cavernae和Lentzea cavernae。本研究通过纯培养方法对贵州喀斯特洞穴放线菌的多样性进行初步掌握,为贵州地区喀斯特洞穴放线菌资源的研究和利用开发奠下了理论基础。此外,分离菌株的抗菌活性筛选结果揭示了喀斯特洞穴中蕴藏着大量具有产活性天然产物的菌株,为筛选结构新颖、活性优越的活性天然产物提供特殊的菌种资源。
[Abstract]:Karst caves in China are relatively rich in resources. However, the study of cave microbial resources in China is still in the initial stage. In this paper, the diversity and distribution of actinomycetes in karst caves in Xingyi and Libo areas of Guizhou Province were studied by pure culture method, and the antimicrobial activity of actinomycetes isolated from karst caves was tested. In order to excavate new active products from it. In this experiment, 458 strains of actinomycetes were isolated and purified from different kinds of samples in karst cave environment in Guizhou province. According to the morphological characteristics of actinomycetes, the strain 458 was preliminarily identified. The results showed that the isolates were distributed in 194 species, 22 families and 44 genera of 11 orders and 22 families under actinomycetes, and the 16SrRNA gene sequence was compared with each other. 15 potential new species with a similarity of less than 98.5%. Micromonospora, (Micromonospora), (Rhodococcus), Microbacillus, (Microbacterium), Streptomyces, (Streptomyces) and Nocardia, (Nocardioides) are the main distribution groups, while the rare groups, such as Motococcus, Acinetococcus, Ehrlla, Dali Stonework, are also distributed. The antibacterial activity of 218 actinomycetes strains was screened. The results showed that 16 of the 81 strains had antimicrobial activity against 10 kinds of indicator bacteria, which showed strong inhibitory effect. At least 46 strains had inhibitory effect on more than 3 kinds of indicator bacteria. Most of the strains with strong antibacterial activity were Streptomyces micromonosporium and distributed in other groups. The results showed that the actinomycetes in karst caves had great potential for exploitation and application of active natural products. Three potential new taxonomic units, YIMA1136T,YIMA1135T and SYSUK10001T, were selected for morphological, physiological and biochemical analysis, chemical component analysis, DNA homology detection and phylogenetic analysis. The taxonomic status of three new species was determined and named Nocardioides cavernae,Nocardia cavernae and Lentzea cavernae.. In this study, the diversity of actinomycetes in karst caves in Guizhou was preliminarily grasped by pure culture methods, which laid a theoretical foundation for the research and exploitation of actinomycetes in karst caves in Guizhou. In addition, the screening results of antimicrobial activity of isolated strains revealed that a large number of strains with active natural products were found in karst caves, which provided special resources for screening active natural products with novel structure and superior activity.
【学位授予单位】：昆明理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：Q93

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