鹭宁两地植物根际土壤中放线菌的生物多样性分析及生物活性检测

Abstract

为探究不同地区植物根际土壤中可培养放线菌的多样性,筛选具有抗菌及抗肿瘤活性的药源菌株,采用改良聚乳酸-明胶和海藻糖-脯氨酸2种培养基,选择分离采; 自厦门市翔安区香山风景区、南京市中山植物园及玄武湖公园的17份植物根际土壤样品中的放线菌,并进行16SrRNA基因鉴定、系统进化分析及抗菌和抗肿; 瘤生物活性测定.共分离到178株放线菌,其中链霉菌151株,其余27株为稀有放线菌,占总数的15.2%.稀有放线菌分布在9个属中:微杆菌属(Mi; crobacterium)、拟无枝酸菌属(Amycolatopsis)、韩国生工菌属(Kribbella)、野野村氏菌属(Nonomuraea); 、小单孢菌属(Micromonospora)、链孢囊菌属(Streptosporangium)、拟孢囊菌属(Kibdelosporangium); 、纤维微菌属(Cellulosimicrobium)和栖白蚁菌属(Isoptericola),包含2株新种.对分离得到的所有放线菌进行液体小量发; 酵,并测定其发酵粗提物的抗菌和抗肿瘤活性.结果显示:所测定的178株放线菌中,有82株对一种或多种指示菌表现出抗菌活性,占供测菌株的46.1%;; 有60株对一种或多种肿瘤细胞具有抑制作用,占供测菌株的33.7%.研究结果表明植物根际土壤中放线菌资源丰富,其中抗菌和抗肿瘤活性较强的菌株可为后; 续微生物药物研发提供有利资源.

To investigate the diversity of actinomycetes from rhizosphere soil in; different regions and to screen the strains with antibacterial and; antitumor activities,the 16SrRNA gene sequencing and phylogenetic; analysis were used to explore the diversity of actinomycetes, which were; isolated from 17rhizosphere soil samples with two selective media.And; then 6bacteria,2fungi and 4tumor cells were used as indicators to; determine the biological activities of actinomycetes.In this study,a; total of 178actinomycetes were isolated from the rhizosphere; soil,including 27strains as rare actinomycetes,which accounted for a; total of 15.2%.The rare actinomycetes can be assigned to 9genera,which; are; Microbacterium,Amycolatopsis,Kribbella,Nonomuraea,Micromonospora,Strepto; sporangium, Kibdelosporangium,Cellulosimicrobium,Isoptericola,and; 2strains of them were novel species.Among the isolated actinomycetes,; 82strains(46.1%)had antibacterial activities against one or more; indicators,60strains(33.7%)had inhibitory activities against one or more; tumor cells.In conclusion,the results show that the rhizosphere soil is; a highly diverse actinobacterial community, in which most of them appear; to be novel candidate species.Therefore,the actinomycetes with; biological activities could be a promising source for secondary; metabolites separation and microbial pharmaceutical developments.