Laboratorio de Microbiología, Facultad de Medicina, Universidad Andrés Bello, Santiago, Chile.
FEMS Microbiol Lett. 2011 Sep;322(2):150-6. doi: 10.1111/j.1574-6968.2011.02347.x. Epub 2011 Aug 1.
Salmonella enterica serovar Typhi and Typhimurium are closely related serovars. However, S. Typhi, a human-specific pathogen, has 5% of genes as pseudogenes, far more than S. Typhimurium, which only has 1%. One of these pseudogenes corresponds to sopD2, which in S. Typhimurium encodes an effector protein involved in Salmonella-containing vacuole biogenesis in human epithelial cell lines, which is needed for full virulence of the pathogen. We investigated whether S. Typhi trans-complemented with the functional sopD2 gene from S. Typhimurium (sopD2(STM) ) would reduce the invasion of human epithelial cell lines. Our results showed that the presence of sopD2(STM) in S. Typhi significantly modified the bacterial ability to alter cellular permeability and decrease the CFUs recovered after cell invasion of human epithelial cell line. These results add to mounting evidence that pseudogenes contribute to S. Typhi adaptation to humans.
肠炎沙门氏菌血清型 Typhi 和 Typhimurium 是密切相关的血清型。然而，人类特异性病原体 S. Typhi 有 5%的基因是假基因，远远超过 S. Typhimurium 的 1%。这些假基因之一对应 sopD2，它在 S. Typhimurium 中编码一种效应蛋白，参与人类上皮细胞系中沙门氏菌含液泡的生物发生，这对于病原体的完全毒力是必需的。我们研究了 S. Typhi 是否可以通过来自 S. Typhimurium 的功能 sopD2 基因（sopD2(STM) ）的转互补来减少对人类上皮细胞系的侵袭。我们的结果表明，sopD2(STM) 在 S. Typhi 中的存在显著改变了细菌改变细胞通透性的能力，并减少了人上皮细胞系细胞侵袭后回收的 CFU。这些结果增加了越来越多的证据表明，假基因有助于 S. Typhi 适应人类。
