枯草芽胞杆菌Bs-916的全基因组分析

The Complete Genome Sequence of the Gram-Positive Bacterium Bacillus subtils Bs-916

【目的】对枯草芽胞杆菌Bs-916进行全基因组测序,为今后更好挖掘和利用该菌生防潜力提供较多的分子生物学信息。【方法】通过应用比较基因组学软件与另一测序菌株Bs168进行全基因组序列分析。【结果】Bs-916菌株全基因组大小为3 925 958 bp,GC含量为46.4%,与其它已测序全基因组芽孢杆菌相比,其GC含量最高;预测所得CDS数为4 056个,152个串联重复区域,转座子103个,IS(插入序列)序列数量37个,tRNA 46个,rRNA 39个;比较基因组学分析其含有8个NRPS/PKS基因簇,其中bacillomycin L,macrolactin,difficidin这3个基因簇在比较菌株Bs168中不存在;该菌还含有植酸酶基因、comAPQX及sfp等与生防因子相关的基因。【结论】Bs-916菌株全基因组含有多种抗菌物质编码基因簇,是一类具有极大生防潜力的典型根际革兰氏阳性菌株。该菌株全基因组序列的测定及其遗传操作方法的可行性,有利于其次生代谢产物的开发和利用。次生代谢产物具有潜在的应用价值,有望在未来开发成独特的农业生物工程制剂。

【Objective】The objective of this study is to sequence the whole genome of Bacillus subtils Bs-916 and provide more information about molecular biology for future mining and utilizing the potential of this strain.【Method】 Application of comparative genomics softwares,the whole genome sequence analysis was carried out with Bs168 strains.【Result】 Bs-916 strains genome is 3 925 958 base pairs comprises 4 056 protein-coding genes.The average GC ratio is 46.4%,the highest compared with other whole-genome sequencing of Bacillus spp..It contains 152 tandem repeat region,103 transposons,37 IS（Insert sequence）,46 tRNA,39 rRNA.Through comparative genomics analysis,Bs-916 harbors eight giant gene clusters directing synthesis of bioactive peptides and polyketides by modularly organized mega-enzymes named non-ribosomal peptide synthetases,NRPS and polyketide synthases,PKS.Macrolactin,difficidin,and bacillomycin L are absent in Bs168 strains.Bs-916 also contains phytase gene,comAPQX and sfp related with biocontrol mechanism.【Conclusion】Bs-916 strain genome contains many gene cluster encoding a variety of antimicrobial substances,it can be considered a paradigm for an own group of plant-associated gram-positive bacteria with a huge potential for biocontrol and plant growth promotion.The complete genome sequence along with its amenability to genetic manipulation,should facilitate exploitation of the hitherto unappreciated potential of strain Bs-916 to produce secondary metabolites for developing agrobiological engineering preparations.