贵州兴义喀斯特洞穴可培养放线菌多样性及抗菌活性初筛

【目的】进一步了解兴义喀斯特洞穴可培养放线菌资源及产活性代谢产物的能力。【方法】选取多种分离培养基,利用稀释直接涂布平板法对贵州黔西南兴义市多个喀斯特洞穴的土壤和岩石进行可培养放线菌资源分离;利用三种发酵培养基对相关放线菌进行生物产物初筛。【结果】根据16S rRNA基因序列的比对分析,将分离得到的251株放线菌分别归类到44个属,其中链霉菌属(Streptomyces)占分离菌株的比例为24.30%,小单孢菌属(Micromonospora)占比11.95%,红球菌属(Rhodococcus)占比9.16%,微杆菌属(Microbacterium)占比7.17%,诺卡氏菌属(Nocardia)占比6.37%,该五类放线菌为该地区可培养放线菌的优势菌群。对70株细菌进行活性次级代谢产物筛选,其中35株放线菌对指示菌具有抑制活性,且主要类群为链霉菌属和小单孢菌属。【结论】贵州兴义喀斯特洞穴中存在丰富多样的放线菌类群,且蕴藏大量具有产生活性次级代谢产物能力的菌株,为医药产业提供潜力菌株资源,极具进一步发掘和研究的价值。

Diversity and antibacterial activity of culturable actinobacteria in karst cave soil in Xingyi, Guizhou

Objective] To investigate the diversity of culturable actinobacteria of samples from karst cave in Xingyi county of Guizhou province and analyze their ability of production of secondary metabolites. Methods] The spread plate method was used to obtain the diversity of culturable actinobacteria from different type karst cave samples (sediment and rock) with many kinds of media. Three ferments media were selected to detect the production of secondary metabolite compounds of these culturable actinobacteria. Results] Through the comparative analysis based on 16S rRNA gene sequences similarities, we obtained a total of 251 isolates belonging to 44 genera, among of which the genera Streptomyces, Micromonospora, Rhodococcus, Microbacterium and Nocardia were the dominant actinobacterial group, and the proportion of them were 24.30%, 11.95%, 9.16%, 7.17% and 6.37%, respectively. During the analysis of production of bioactivity of secondary metabolite compounds, 35 isolates showed the bioactivity to the indicator pathogen bacteria, among of which were main from the genera Streptomyces and Micromonospora. Conclusion] The results indicated that there were richness actinobacterial resources in the karst cave niche in southwest of Guizhou, and much more isolates had the ability to produce secondary metabolite compounds, which would become potential species for the pharmaceutical industry, and hence it had the most value for further exploration and research.