Probiotics Down-Regulate Genes in Salmonella enterica Serovar Typhimurium Pathogenicity Islands 1 and 2
Probiotics Down-Regulate Genes in Salmonella enterica Serovar Typhimurium Pathogenicity Islands 1 and 2
复制标题
DOI：
10.4315/0362-028x-73.3.452
复制
发表时间：
2010-03-01
影响因子：
2
通讯作者：
Griffiths, Mansel W.
中科院分区：
文献类型：
--
作者：
Bayoumi, Mohamed A.;Griffiths, Mansel W.
鼠伤寒沙门氏菌的致病机制主要依赖于两个致病岛基因的表达，即沙门氏菌致病岛1和2（SPI1和SPI2）。每个岛屿都有自己的表达和调节模式。成功抑制每个岛的关键激活因子将是控制沙门氏菌的有效方法，特别是在出现耐药性菌株的问题时。益生菌已被证明可以抑制几种食源性病原体，其作用模式可能部分涉及毒力基因的下调。为了研究益生菌是否在沙门氏菌中的致病岛SPI1和SPI2的调节中发挥作用，构建了两个报告菌株，其中SPI1的一般调节因子hilA和SPI2的反应调节因子ssrB与luxCDABE基因融合。这些构建体用于筛选益生菌对每个基因表达的影响。两歧双歧杆菌分泌的分子能够下调这两个基因。
Salmonella Typhimurium pathogenesis relies mainly on the expression of genes of two pathogenicity islands, Salmonella pathogenicity islands 1 and 2 (SPI1 and SPI2). Each island has its own pattern of expression and regulation. Success in suppression of the responsible key activator of each island would be an effective way of controlling Salmonella, especially with the emerging problem of antibiotic-resistant strains. Probiotics have been shown to inhibit several foodborne pathogens, and their mode of action may partly involve down-regulation of virulence genes. To investigate whether probiotics played a role in the regulation of the pathogenicity islands SPI1 and SPI2 in Salmonella, two reporter strains were constructed in which the general regulator of SPI1, hilA, and the response regulator of SPI2, ssrB, were fused with luxCDABE genes. These constructs were used to screen the effect of probiotics on the expression of each gene. Molecules secreted by Bifidobacterium bifidum were able to down-regulate both genes.