苏云金芽胞杆菌XL6 BTXL6_11095基因对生物被膜相关表型的调控

在细菌生物被膜（bacterial biofilm,BBF）状态下，细菌往往具有更强的抗紫外线能力、环境适应性和耐药性。本课题组在前期工作中通过转座子插入突变强生物被膜产生菌苏云金芽胞杆菌（Bacillus thuringiensis，Bt）XL6，筛选出了一个可能调控生物被膜的基因BTXL6_11095。本文以该基因为研究对象，通过生物信息学手段分析该基因功能，构建了BTXL6_11095基因敲除菌株，并对其生物被膜相关表型进行了分析。生物信息学分析结果表明BTXL6_11095基因的结构域为PAS-GGDEF-GGDEF-EAL。生物被膜相关表型分析表明，与野生菌株相比，基因敲除菌株的生长曲线基本不变，群游能力上升，生物被膜形成能力减弱、UV-B抗性降低。本研究通过对BTXL6_11095基因表型变化综合评估，从功能角度揭示此基因对Bt XL6生物被膜相关表型的影响，为进一步解析Bt XL6生物被膜调控网络和构建高抗UV的工程生物被膜奠定了基础。

Regulation of the BTXL6_11095 Gene of Bacillus thuringiensis XL6 on Its Biofilm-Related Phenotypes

Under the condition of bacterial biofilm (BBF), bacteria tend to have higher anti-UV-B ability, better environmental adaptability and stronger pesticide resistance. In our previous studies, the BTXL6_11095 gene putatively with the function regulating biofilm formation was screened by transposon insertion into the genome of Bacillus thuringiensis (Bt) XL6 with strong biofilm formation ability. In this study, the potential functions of this gene were analyzed using bioinformatics using BTXL6_11095 knockout mutant and through analysis of the biofilm related phenotypes of the mutant. Bioinformatics analysis showed that BTXL6_11095 gene had the PAS- GGDEF-GGDEF-EAL motif. BTXL6_11095 knockout mutant showed no different growth curve relative to the wild type, but exhibited higher swimming ability, lower biofilm formation ability, and lower resistance to UV-B. This study, through comprehensive evaluation of phenotypic changes of BTXL6_11095 knockout mutant, has revealed the effect of this gene on the biofilm formation ability of Bt XL6, which serves to elucidate biofilm regulation network of Bt XL6 and construct its engineered biofilm with high biofilm formation ability.