芽孢杆菌蛋白酶基因的比较基因组学分析  

Comparative Genomics Analysis of Protease Genes in Bacillus sp.

作　　者：贾仲昕 赵佳男 季芳 王雪 李刚 王承民 秦建华[1] JIA Zhongxin;ZHAO Jianan;JI Fang;WANG Xue;LI Gang;WANG Chengmin;QIN Jianhua(College of Veterinary Medicine,Agricultural University of Hebei,Baoding 071000,China;Institute of Zoology,Guangdong Academy of Science/Guangdong Key Laboratory of Animal Conservation and Resource Utilization/Guangdong Public Laboratory of Wild Animal Conservation and Utilization,Guangzhou 510260,China)

机构地区：[1]河北农业大学动物医学院,河北保定071000 [2]广东省科学院动物研究所/广东省动物保护与资源利用重点实验室/广东省野生动物保护与利用公共实验室,广东广州510260

出　　处：《广东农业科学》2022年第5期110-117,共8页Guangdong Agricultural Sciences

基　　金：河北省现代农业产业技术体系奶牛创新团队建设项目(HBCT2018120205);河北省重点研发项目(20326603D);广东省科学院人才专项(2016GDASRC-0205);北京动物园圈养野生动物技术北京市重点实验室开放课题(ZDK202105)。

摘　　要：【目的】研究芽孢杆菌产蛋白酶能力与携带的蛋白酶基因的关系,探寻影响芽孢杆菌产蛋白酶能力的重要基因。【方法】通过筛选培养基筛选能够产生蛋白酶的菌株,采用福林酚法检测菌株产生的蛋白酶的活性,对15株芽孢杆菌分离株进行全基因组测序,获得菌株染色体上携带的蛋白酶基因情况并将其分类;采用实时荧光定量PCR方法检测蛋白酶基因mRNA的转录水平;通过比较基因组学和细菌全基因组关联分析(BGWAS),探讨影响细菌产蛋白酶能力高低的原因。【结果】根据菌株染色体上携带的蛋白酶基因情况,可分为7种基因型(G1~G7)。比较基因组学和BGWAS分析发现,细菌染色体上携带的蛋白酶基因种类的多寡与其产蛋白酶能力的高低有直接关系,且缺少aprX和aprE基因菌株的产蛋白酶能力明显下降。进一步研究基因mRNA水平发现,芽孢杆菌产蛋白酶能力的差异与aprX的表达水平有关。【结论】菌株染色体上携带的蛋白酶基因情况与菌株产蛋白酶能力之间存在关联。aprX是影响芽孢杆菌属细菌产胞外蛋白酶能力的重要基因。【Objective】The study aims to explore the relationship between the protease-producing capacity of Bacillus and the protease genes carried by the bacteria and analyze the important enzyme genes that affect the protease-producing capacity of Bacillus.【Method】The protease-producing strain was screened by using the selective medium.The protease activity of the strains was determined by the Folin method.The protease genes carried on the chromosomes of the strains were obtained and classified by sequencing the whole genome of 15 strains of Bacillus.The transcription level of protease gene mRNA was measured by the real-time fluorescent quantitative PCR method.Through comparative genomics and Bacterial Genome-Wide Association Analysis (BGWAS),the reasons that affect the ability of bacteria to produce protease were explored.【Result】According to the protease genes carried on the chromosomes of the strains,they could be divided into 7 groups of genotypes (G1-G7).Comparative genomics and BGWAS found that the number of protease genes carried on bacterial chromosomes was directly related to the protease production capacity,and the protease production capacity of strains lacking aprX and aprE was significantly reduced.The difference in the protease production capacity of Bacillus was found to be related to the expression level of aprX by further studying the mRNA level of the gene.【Conclusion】There is a correlation between the protease gene carried on the chromosome of the strain and the protease production capacity of the strain.The important enzyme gene that affects the protease production capacity of Bacillus is aprX.

关 键 词：蛋白酶 芽孢杆菌 比较基因组学 荧光定量PCR aprX基因 

分 类 号：S816[农业科学—饲料科学] Q753[农业科学—畜牧学]