解淀粉芽孢杆菌群体遗传特征分析

Population Genetic Characteristics of Bacillus amyloliquefaciens

通过平均核苷酸一致性分析、基因预测、泛基因组构建、功能注释等流程,以66株解淀粉芽孢杆菌(Bacillus amyloliquefaciens)的基因组为对象,进行该物种的泛基因组分析。平均核苷酸一致性分析表明,上述菌株可划为具有明显物种边界的两个独立分支;获得的泛基因组共包含13051个基因,其中核心基因2165个;碳水化合物活性酶(carbohydrate-active enzymes,CAZy)功能注释显示,B.amyloliquefaciens相比Bacillus属内其他菌株在分解淀粉、β-葡聚糖和木聚糖上具有较大优势;在促植物生长方面,B.amyloliquefaciens通过吲哚丙酮酸途径合成吲哚乙酸,并通过碱性磷酸脂酶和植酸酶分解磷元素;抗生素耐药性分析发现,多数菌株含链霉素以及大环内酯类抗生素抗性基因。此外,在所有基因组中均发现杆菌烯和杆菌肽等次级代谢产物基因簇。上述研究进一步明确B.amyloliquefaciens基因组水平的分类学特点、核心基础代谢特征,以及菌株在碳水化合物代谢、植物促生、生物防治等方面的优势及潜力,可为开发利用该菌作参考。

Through processes such as average nucleotide identity analysis,gene prediction,pan-genome construction,and functional annotation,the genome of 66 strains of Bacillus amyloliquefaciens was subjected to pan-genome analysis.The average nucleotide identity analysis showed that the above strains could be divided into two distinct branches with clear species boundaries.The obtained pan-genome contained 13051 genes,including 2165 core genes.Carbohydrate-active enzymes(CAZy)functional annotation showed that B.amyloliquefaciens had significant advantages over other Bacillus species in the degradation of starch,β-glucan,and xylan.Regarding plant growth promotion,B.amyloliquefaciens synthesized indole-3-acetic acid through the indole-3-pyruvic acid pathway and utilized alkaline phosphatase and phytase to release phosphorus.Antibiotic resistance analysis revealed the presence of genes conferring resistance to streptomycin and macrolide antibiotics in most strains.Additionally,secondary metabolite gene clusters such as baculene and bacitracin were identified in all genomes.This study further elucidated the taxonomic characteristics and core metabolic features of the B.amyloliquefaciens genome,as well as the advantages and potential of strains in carbohydrate metabolism,plant growth promotion,and biocontrol.These findings can serve as a reference for the better development and utilization of this bacterium.