肠炎沙门菌双组份系统qseC基因缺失株的构建及其生物学特性分析

Construction of Two-component System qseC Gene Deletion Strain of Salmonella Enteritidis and Its Biochemical Characteristics Analysis

为研究肠炎沙门菌qseC基因功能,构建qseC缺失株C50041ΔqseC以及回复株C50041ΔqseC::qseC,分析qseC基因缺失对肠炎沙门菌生化特性、生长曲线、运动性、黏附侵袭等方面的影响,探究该基因在肠炎沙门菌感染致病中的作用。结果显示:利用框内缺失突变技术成功获得肠炎沙门菌C50041ΔqseC缺失株,以野生株C50041、回复株C50041ΔqseC::qseC为对照,发现C50041ΔqseC缺失株的生化特性、生长曲线与C50041野生株一致,但其运动性(P=0.0019)以及对巨噬细胞J774A.1的黏附率(P=0.0325)、侵袭率(P=0.0053)相比野生株显著下降。研究提示:qseC基因的缺失对肠炎沙门菌的生化特性和生长曲线没有影响,但会显著降低肠炎沙门菌的运动能力及对宿主细胞的黏附和侵袭。研究初步探究了肠炎沙门菌qseC基因的功能,为后续深入研究奠定基础。

The effects of qseC gene on the biochemical characteristics of growth,motility,adhesion and invasion of Salmonella Enteritidis were investigated by constructing the deletion strain C50041ΔqseC,the complementary strain C50041ΔqseC::qseC,respectively.The results showed that the strain of C50041ΔqseC was successfully constructed by in-frame deletion system.The biochemical characteristics and growth curve of Salmonella Enteritidis C50041ΔqseC strain were the same as that of C50041 wildtype and C50041ΔqseC::qseC complementary strains.However,the motility,adhesion and invasion rate of Salmonella Enteritidis C50041ΔqseC strain decreased significantly compared with C50041 wildtype strain,indicating that loss of qseC gene influences the motility and virulence of Salmonella Enteritidis.It is suggested that qseC gene has no effect on the biochemical and growth characteristics of Salmonella Enteritidis,but affects its motility,adhesion and invasion ability in J774A.1 macrophage cells,which laid foundation for further re⁃search.