摘要
根际是土壤-植物根系-微生物进行物质交换的活跃地带。根际放线菌是根系放线菌的重要组成部分,是生物活性物质的主要来源之一。本研究从海南东寨港红树林自然保护区采集了5份红树植物老鼠簕根际土壤样品,采用高通量测序和传统纯培养相结合的策略探究样品中根际放线菌的多样性和产生生物活性物质的潜力。利用Illumina Novaseq6000测序平台对老鼠簕根际样品细菌的16SrRNA基因的V3~V4区域进行测序与分析,结果显示:(1)老鼠簕根际细菌共注释到32个门(包括25个有效鉴定的门),其中优势门是变形菌门;α多样性分析表明老鼠簕根际细菌群落多样性非常丰富;(2)对放线菌门的微生物群落进行分析,注释到33个有效鉴定的属、4个暂定的属和28个未培养的新放线菌属,KEGG功能预测分析显示老鼠簕根际放线菌主要参与次级代谢产物的生物合成。同时,利用传统纯培养方法分离放线菌,经形态特征分群和排重,通过PCR扩增、测序并比对16SrRNA基因序列后进行放线菌多样性分析,利用琼脂扩散法筛选抑菌活性,通过基于PCR的基因筛选技术检测代表菌株可能存在的PKS-Ⅰ、PKS-Ⅱ和NRPS抗生素生物合成基因,结果显示:(1)共得到4个属的33株放线菌代表菌株,其中链霉菌属为优势菌属,有2个属未被高通量测序分析结果注释到;(2)代表菌株的NRPS和PKS-Ⅱ基因阳性率很高(90%以上),24.24%根际放线菌具有抗1种及以上指示菌的活性。本研究利用高通量测序和纯培养方法得出东寨港红树植物老鼠簕的根际放线菌多样性非常丰富,并具有较好的合成次生代谢产物的潜力,因此,该研究结果可为具有生物活性化合物的筛选提供丰富的菌种资源,同时也为后续新药的开发提供重要参考依据。
Rhizosphere is a dynamic interface where soil,plant roots and microorganisms exchange substances.Rhizospheric actinomycetes are an important component of root actinomycetes and one of the main sources of bioactive substances.In this study,five different rhizospheric soil samples of a mangrove plant,Acanthus ilicifolius,were col-lected from the Dongzhaigang Mangrove Nature Reserve of Hainan province.A combination of high-throughput se-quencing and traditional pure culture strategies were used to explore the diversity of the rhizospheric actinomycetes of A.ilicifolius and the potential to produce bioactive substances in the samples.The V3 to V4 regions of 16S rRNA gene in the rhizospheric samples of A.ilicifolius were sequenced and analyzed by Illumina Novaseq 6000 sequencing platform.A total of 32 phyla(including 25 effectively identified phyla)were annotated,of which Proteobacteria is the dominant phyla.α-diversity analysis showed that the rhizospheric bacterial community of A.ilicifolius was very abundant.The microbial communities of actinomycetes were analyzed,and 33 validated genera,four tentative genera and 28 uncul-tured new genera were noted.KEGG functional prediction analysis in different levels showed that rhizospheric actino-mycetes were mainly involved in the biosynthesis of secondary metabolites including various antibiotics.Meanwhile,actinomycetes were isolated by the traditional pure culture method.After isolation,purification,morphological charac-teristics grouping and rearrangement,the diversity of actinomycetes of mangrove A.ilicifolius was analyzed by PCR amplification,sequencing and comparison of 16S rRNA gene sequences.The antimicrobial activity was screened by the agar diffusion method.PCR-based gene screening technology was used to detect the possible antibiotic biosynthesis genes of the representative strains of PKS-Ⅰ ,PKS-Ⅱand NRPS.A total of 33 representative strains of rhizospheric ac-tinomycetes were obtained from four genera,of which Streptomyces was the dominant genus,and 2 genera
作者
刘顺卿
何小稳
吴金燕
易国辉
陈芊芊
谢欣宜
隋金蕾
LIU Shunqing;HE Xiaowen;WU Jinyan;YI Guohui;CHEN Qianqian;XIE Xinyi;SUI Jinlei(Public Research Center,Hainan Medical University,Haikou,Hainan 571199,China;School of Basic Medicine and Life Science,Hainan Medical University,Haikou,Hainan 571199,China)
出处
《热带作物学报》
CSCD
北大核心
2024年第7期1498-1510,共13页
Chinese Journal of Tropical Crops
基金
海南省基础与应用基础研究计划(自然科学领域)高层次人才项目(No.2019RC216)
海南医学院引进人才科研启动基金项目(No.XRC190006)
海南医学院(国家级)大学生创新创业训练计划项目(No.202311810008)。
关键词
老鼠簕
根际
放线菌多样性
高通量测序
纯培养
Acanthus ilicifolius
rhizosphere
actinomycetic diversity
high-throughput sequencing
pure culture
