胡椒瘟病生防菌Bacillus subtilis VD18R19全基因组测序及比较基因组学分析

Whole Genome Sequencing and Comparative Genomics Analysis of Bacillus subtilis VD18R19 with Biocontrol Activity Against Pepper Phytophtora Rot Disease

Bacillus subtilis VD18R19具有促进胡椒生长和防治胡椒瘟病的效果,全基因组测序是其分子机理研究和开发利用的重要基础。本研究采用第二代Illumina平台与第三代PacBio平台相结合的测序技术,对生防菌VD18R19进行全基因组测序,并进行比较基因组学分析。结果发现,VD18R19全基因组大小为4123380bp,GC含量为43.80%,编码基因4 245个;含有tRNA 85个、rRNA 30个、sRNA 33个;含有串联重复序列60个,其中小卫星DNA 43个、微卫星DNA 1个;共线性分析、core-pan基因分析及基因家族分析结果均显示VD18R19与模式菌株B. subtilis 168具有高度的同源性;antiSMASH软件预测及同源序列比对结果显示,VD18R19菌株中含有6个抑菌次生代谢产物合成基因簇,编码surfactin、plipastatin、bacillibactin、bacilysin、bacillaene、subtilosinA等抑菌物质,其合成途径涵盖了核糖体途径、非核糖体途径和聚酮合酶途径。本研究为深入研究生防菌VD18R19的分子机理奠定生物信息学基础,有利于生防菌株及其抑菌次生代谢产物的开发和利用。

Bacillus subtilis VD18 R19 has beneficial effects on pepper growth-promoting and bio-control against pepperPhytophtora rot disease. The whole genome sequencing is an important basis for further molecular research and application. The genome was sequenced using a PacBio RS II platform and Illumina HiSeq 4000 platform, and the gene function annotation and comparative genomics analysis were performed using blast alignment tools. The genome is 4 123 380 bp with GC content of 43.80%, 4 245 identified genes, 85 tRNA, 30 rRNA, 33 sRNA, 60 tandem repeat regions including 43 minisatellite DNA and 1 microsatellite DNA. The genome showed highly homologous with the model strain B. subtilis 168 by the analysis of genome synteny, core-pan gene and gene family. It harbors six antibiotic gene clusters, directing synthesis of surfactin, plipastatin, bacillibactin, bacilysin, bacillaene and subtilosin A, through ribosomal synthetases（RS） pathway or non-ribosomal peptide synthetases（NRPS） pathway or polyketide synthases（PKS） pathway. This study would provide a database for further research of diverse molecular biology mechanisms and is helpfull in utilizing the beneficial strain and the functional antibiotics.