基于转座子突变获得苏云金芽胞杆菌解毒Cr(Ⅵ)的相关基因功能分析  

Functional Analysis of Genes Controlling Detoxification of Cr(Ⅵ) in Bacillus thuringeinsis with Transposon Mutagenesis

作　　者：黄天培[1] 张君[1] 康榕[1] 赖小华[1] 潘洁茹[2] 张灵玲[1,3] 关雄[1] 

机构地区：[1]福建农林大学生物农药与化学生物学教育部重点实验室,福建福州350002 [2]福州市疾病预防控制中心,福建福州350004 [3]福建农林大学国家菌草工程技术研究中心,福建福州350002

出　　处：《热带作物学报》2014年第4期724-728,共5页Chinese Journal of Tropical Crops

基　　金：国家自然科学基金"基于基因搜索和转座子组学的生物被膜新基因克隆及其生防功能分析"(No.31201574);福建省教育厅项目"教育厅高校领军人才"(No.k8012012a);植物病虫害生物学国家重点实验室开放基金项目"生物被膜相关基因对苏云金芽胞杆菌生防能力的影响及其机制"(No.SKL2012OP05);国家菌草工程技术研究中心开放基金"利用食用菌菌糟制备生物农药苏云金杆菌"(No.JCJJ13021)

摘　　要：为了获得苏云金芽胞杆菌(Bacillus thuringiensis,简称Bt)解毒Cr(Ⅵ)的相关基因并进行功能分析,从Bt407转座子随机突变体库筛选并获得了9株Cr(Ⅵ)还原能力突变株,测定了其转座子插入位点,并研究了表型变化。这些突变株的Cr(Ⅵ)还原能力比野生株极显著提高(p<0.01),其转座子插入位点均为编码假定的肽链内切酶yddH基因。研究结果表明,野生株与突变株的生长曲线没有显著差异,说明突变株Cr(Ⅵ)还原能力的极显著提高与菌种数量改变无关。突变株总铬含量基本保持不变,表明Bt 407主要是通过将Cr(Ⅵ)还原为Cr(Ⅲ)来解毒Cr(Ⅵ)。本研究为构建高效解毒Cr(Ⅵ)工程菌提供了新候选基因材料。In order to analyze the functions of genes controlling detoxification of Cr（Ⅵ ） in Bacillus thuringeinsis with transposon mutagenesis, the mutants with different Cr（Ⅵ ） reduction capacity were obtained from a library of Bt 407 transposon random insertion mutants. The insertion sites and the phenotypes of the mutants were then determined. 9 mutants which Cr（Ⅵ ） -reducing capacities were remarkably different（p〈0.01） from Bt 407 were obtained. The flanking sequence of mini-Tn10 insertion in the mutants was sequenced and within putative endopeptidase yddH gene. The results showed that the growth curves of all strains were similar. This indicated that strain populations did not affect the Cr（Ⅵ ） reduction capacities of the mutants. The observation that total Cr of Bt 407 and its 9 mutants were similar and waved among 50 mg/L suggested that they mainly detoxify Cr（Ⅵ ） by reduction. Herein, the putative endopeptidase yddH gene might be a novel gene for construction of engineering strains detoxifying Cr（Ⅵ） with high efficiency.

关 键 词：苏云金芽胞杆菌 转座子 肽链内切酶 Cr(Ⅵ) 还原 

分 类 号：Q939.9[生物学—微生物学]