基于全基因组测序解析贝莱斯芽孢杆菌产胞外多糖的分子基础

Whole Genome Sequencing for Analysis of the Molecular Basis for Extracellular Polysaccharide Production by Bacillus velezensi

本研究采用二代Illumina HiSeq与三代Pacbio平台相结合的全基因组测序技术,对分离自郫县豆瓣的产胞外多糖菌株贝莱斯芽孢杆菌(Bacillus velezensis)L-39进行全基因组测序。对B.velezensis L-39进行完整的基因组装、预测、注释、次级代谢产物合成基因簇和关键基因功能分析,重点关注其碳水化合物代谢、核苷糖合成途径以及胞外多糖生物合成基因簇。结果显示,B.velezensis L-39全基因组大小为3970591 bp,共编码3770个基因。通过京都基因与基因组百科全书数据库进行途径分析,在基因组中预测出一条eps基因簇和32个功能基因,绘制出一条完整的胞外多糖合成通路。在此基础上对关键基因进行了聚合酶链式反应扩增验证,结果与预期相符。本研究旨在发掘与该菌株胞外多糖合成密切相关的基因,为深入解析其胞外多糖产生的分子基础和实际应用开发提供科学依据。

In this study,whole genome sequencing of Bacillus velezensis L-39,an extracellular polysaccharide-producing strain isolated from Pixian Douban,was carried out through the combined use of second-generation Illumina HiSeq and third-generation PacBio platforms.The genomic analysis covered gene assembly,prediction,annotation,and the elucidation of secondary metabolite biosynthetic gene clusters and crucial gene functions,focusing on the gene clusters for carbohydrate metabolism,the nucleoside sugar synthesis pathways,and extracellular polysaccharide biosynthesis.The results showed that the whole genome size of B.velezensis L-39 was 3970591 bp in length,encoding a total of 3770 genes.Through Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway analysis,the eps gene cluster and 32 functional genes were predicted from the genome,and a complete extracellular polysaccharide(EPS)synthesis pathway was mapped.Subsequently,polymerase chain reaction(PCR)was performed on the pivotal genes,with results expected.The aim of this study is to discover genes closely related to extracellular polysaccharide synthesis by B.velezensis L-39 in order to provide a scientific foundation for an in-depth analysis of the molecular basis for extracellular polysaccharide production by this strain and for its practical application and development.