沙门菌毒力岛基因在不同血清型沙门菌中的分布特点

Distribution of Salmonella pathogenicity island genes in different Salmonella serovars

目的研究沙门菌毒力岛1(SPI-1)和3(SPI-3)部分基因在不同血清型和分离株中的分布特点,分析其与毒力进化的关系。方法采用变性高效液相色谱(DHPLC)法对分属于6个不同血清型的40株沙门菌毒力岛1上和3上的20个基因进行检测。结果鼠伤寒沙门菌、鸡伤寒沙门菌和肠炎沙门菌的20个基因全部为阳性;猪霍乱沙门菌和山夫顿堡沙门菌缺失SPI-3的sugR和rhu M基因。同一血清型、不同年代和不同地区的沙门菌分离株,其毒力岛基因分布完全相同。结论沙门菌毒力岛基因在不同血清型沙门菌中的变异,说明沙门菌的毒力岛是分阶段进化而来;同一血清型不同菌株的相似性,又说明其毒力基因的相对稳定性。

Objective To study the distribution of SPI - 1 and SPI - 3 genes in 40 Salmonella strains of 6 Salmonella enterica serovars, and the relations to the evolution of virulence in Salmonella strains. Methods Twenty SPIs genes were tested in 40 Salmonella strains of 6 Salmonella enterica serovars using denaturing high - performance liquid chromatography （DHPLC）. Re- sults Twenty genes were all detected in Salmonella Typhimurium, Salmonella Gallinarum and Salmonella Enteritidis strains, however, the SPI -3 gengs sugR and rhuM were lost in Salmonella Choleraesuis and Salmonella Senftenberg strains. The gene distribution was the same in different strains of the same serovar. Conclusion The SPIs genes variations in different Salmonella serovars showed the evolution of virulence in Salmonella in different times. The genes similarity in different strains of the same serovar showed the relative stability of virulence genes.