耐盐芽孢杆菌SF-18的生防潜能与基因组学分析  

Biocontrol potential and genomic analysis of salt tolerant bacterium Bacillus sp.SF-18

作　　者：阎春兰[1] 余福燕 王艺霏 李潇潇 彭仙凤 程国军[1] YAN Chunlan;YU Fuyan;WANG Yifei;LI Xiaoxiao;PENG Xianfeng;CHENG Guojun(College of Life Sciences,South-Central Minzu University,Wuhan 430074,China)

机构地区：[1]中南民族大学生命科学学院,武汉430074

出　　处：《华中农业大学学报》2024年第4期192-203,共12页Journal of Huazhong Agricultural University

基　　金：国家自然科学基金项目(32372809);省级大学生创新创业训练计划项目(SCX2023058)。

摘　　要：为从极端环境中分离具有优良抗菌活性的生物防治菌剂,采用稀释涂布平板法从新疆阿克苏盐碱地土样中分离筛选到1株具有明显抑菌作用的耐盐菌株SF-18;以大丽轮枝菌为指示菌,利用牛津杯法测定该菌株发酵液拮抗活性的稳定性,并利用2代和3代测序技术获得该菌株完整的基因组序列,对测序数据进行基因组装、预测、功能注释及次级代谢产物合成基因簇预测。结果显示,该菌株对金黄色葡萄球菌和大丽轮枝菌具有明显的抑制作用,能在18%NaCl的条件下生长;SF-18菌体发酵液在-20~80℃均具有较强的抑菌活性,能耐受pH 5~12的酸碱度环境;通过16S rDNA基因和gyrB基因序列分析,鉴定SF-18菌株隶属于芽孢杆菌属(Bacil⁃lus);全基因序列分析结果显示菌株有480个基因参与了多种碳源的代谢,含有编码亚精胺和海藻糖等与菌株抗逆性相关化合物合成的基因,以及能够降解病原菌细胞壁的葡聚糖酶、几丁质酶等酶的相关基因;次生代谢产物预测分析SF-18含有合成bacillaene、bacillibactin等多种抗性化合物的基因簇,推测菌株SF-18可能通过产生抑菌性的次生代谢产物以及相关降解酶来达到抑菌的效果,在农业生物防治中具有较好的应用前景。The dilution coating plate method was used to isolate and screen a salt-tolerant strain SF-18 with significant antibacterial activity from soil samples in Aksu saline alkali land,Xinjiang to obtain biocontrol agents with elite antibacterial activity from extreme environments.The stability of the antagonistic activity of the supernatant of strain SF-18 cell-free fermentation was determined using the Oxford Cup method,with the Verticillium dahliae as an indicator strain.The whole genome of strain SF-18 was sequenced with Illumina Novaseq platform and PacBio sequel platform.Data sequenced were used to assembly gene,annotate the function of gene,and predict gene clusters involved in synthesizing secondary metabolites.The results showed that strain SF-18 had a significant inhibitory effect on Staphylococcus aureus and Verticillium dahliae,and grew in the broth containing 18%NaCl.The supernatant of strain SF-18 cellfree fermentation had strong antibacterial activity at−20-80℃and tolerated pH 5-12 environments.The strain SF-18 was identified as belonging to the genus Bacillus based on analyzing the sequence of 16S rDNA gene and gyrB gene.The results of whole genome analysis showed that there were 480 genes of strain SF-18 involved in the metabolism of multiple carbon sources,including genes encoding compounds related to stress resistance such as spermidine and trehalose,and genes related to enzymes such as glucanase and chitinase that can hydrolyze the cell wall of pathogen.The results of predicting secondary metabolites showed that strain SF-18 contained gene clusters involved in synthesizing a various of resistant compounds including bacillaene,bacillibactin,mersacidin,fengycin,zwittermicin.It is speculated that strain SF-18 may achieve antibacterial effects by producing antibacterial secondary metabolites and related degradation enzymes,and has good application prospects in biological control of agriculture.

关 键 词：耐盐菌 芽孢杆菌 生物防治 基因组学 大丽轮枝菌 次生代谢产物 

分 类 号：S476.1[农业科学—农业昆虫与害虫防治]