转录调控因子AbrB对生防短短芽胞杆菌X23中抗生素edeines生物合成的影响  

Effect of Transcription Factor AbrB on the Biosynthesis of Antibiotic Edeines in Biocontrol Bacteria Brevibacillus brevis X23

作　　者：张亮 吕翠 段彩琛 王运生[2] 黄军 杜杰 黎定军[1,4] 刘清术 陈武 ZHANG Liang;Lü Cui;DUAN Caichen;WANG Yunsheng;HUANG Jun;DU Jie;LI Dingjun;LIU Qingshu;CHEN Wu(College of Agronomy,Hunan Agricultural University,Changsha 410128,China;College of Plant Protection,Hunan Agricultural University,Changsha 410128,China;Hunan Province Microbiology Institute,Applied Fungi laboratory,Changsha 410009,China;Hunan University of Technology and Business,Changsha 410205,China)

机构地区：[1]湖南农业大学农学院,长沙410128 [2]湖南农业大学植物保护学院,长沙410128 [3]湖南省微生物研究院,应用真菌室,长沙410009 [4]湖南工商大学,长沙410205

出　　处：《中国生物防治学报》2020年第4期564-574,共11页Chinese Journal of Biological Control

基　　金：国家自然科学基金(31772216,31501698,31101482);湖南省自然科学基金(2019JJ40169,2019JJ40119,2019JJ40153);湖南省重点研发计划(2019NK2192);湖南省烟草公司科技项目(17-20Aa01)。

摘　　要：非核糖体类抗生素edeines是短短芽胞杆菌Brevibacillus brevis X23产生的主要抑菌物质,提高其产量有助于增加生防效果。通过全基因组测序及生物信息学分析挖掘短短芽胞杆菌X23的全局性调控因子,基于Red/ET同源重组技术构建温敏型敲除载体,通过双交换同源重组技术获得短短芽胞杆菌X23全局性转录负调控因子缺失的突变株,然后采用平板抑菌、液相色谱-质谱联用(HPLC-MS)和实时荧光定量PCR研究了全局性转录负调控因子敲除对短短芽胞杆菌X23不同生长时期发酵液的抑菌活性、edeines产量、ede操纵子转录水平的影响。从短短芽胞杆菌X23基因组中挖掘到了1个全局性转录负调控因子AbrB,敲除abrB基因后edeines生物合成基因簇操纵子的转录水平在生长前期显著提高,在发酵48 h后abrB突变株中edeine A和edeine B总产量比出发菌株提高了1.1倍。结果显示短短芽胞杆菌X23中AbrB是edeines生物合成过程中的负调控因子,敲除abrB提高了edeines的产量。Non-ribosomal antibiotic edeines are the main bacteriostatic secondary metabolites in Brevibacillus brevis strain X23.Increasing their yields could contribute to improving the bio-control efficiency of X23.Wholegenome sequencing and bioinformatics analysis was used to discover global transcription factors.The global negative transcription factor deletion mutants of X23 were constructed by double-crossover homologous recombination via a temperature-sensitive knockout vector based on Red/ET homologous recombination.Then,the varieties on antibacterial activity,edeines production and the transcription level of Biosynthetic Gene Cluster(BGC) were evaluated by plate antibacterial assay,liquid chromatography-mass spectrometry(HPLC-MS) and real-time quantitative PCR at different growth stages,respectively.A global negative transcription factor AbrB was deleted from the genome of Br.brevis X23,and then the transcription level of the ede BGC operon significantly increased in the early growth stage.The total yields of edeine A and edeine B in the abrB mutant increased by 1.1 times compared with the original strain after 48 h fermentation in conventional fermentation medium.It was proved that AbrB is a negative regulator of edeines biosynthesis processing in Br.brevis X23 and lacking regulation caused by abrB can increase edeines yields.

关 键 词：短短芽胞杆菌 edeines 转录调控 ABRB Red/ET同源重组 

分 类 号：S476.8[农业科学—农业昆虫与害虫防治]