鼠伤寒沙门菌7个未知功能岛在致病性中的作用  

Contribution of seven genomic islands of unknown functions to Salmonella Typhimurium pathogenicity

作　　者：蒋玲艳[1,2] 江小涵 王培胜[2] 杨斌[2] 

机构地区：[1]南开大学环境科学与工程学院,天津300350 [2]南开大学泰达生物技术研究院,天津300457

出　　处：《微生物学通报》2017年第8期1918-1926,共9页Microbiology China

基　　金：中国博士后科学基金项目(No.2016M591381);国家国际科技合作专项项目(No.2012DFG31680);国家自然科学基金项目(No.31470194)~~

摘　　要：【目的】探索沙门菌在进化过程中通过水平转移获得的未知功能岛在其致病过程中的作用,发现新的与致病性相关的岛。【方法】以鼠伤寒沙门菌ATCC 14028为亲本株,利用λRed重组酶系统分别构建了7个未知功能岛(STM14_0667-0673、2682-2687、2885-2891、3721-3728、4247-4253、4823-4828、5331-5341)的突变株,通过细胞侵袭实验、巨噬细胞内复制力检测及小鼠实验比较了野生型和突变株的毒力差异。【结果】Δ2682-2687和Δ5331-5341对上皮细胞的侵袭力显著低于野生型(P<0.01);Δ2682-2687、Δ2885-2891和Δ5331-5341在巨噬细胞内的复制力、对小鼠的致死率以及在小鼠肠道和肝、脾的定殖能力均显著低于野生型(P<0.05);其余4个突变株(Δ0667-0673、Δ3721-3728、Δ4247-4253、Δ4823-4828)的侵袭力、胞内复制力以及对小鼠的致病力与野生型相比无显著差异。【结论】发现3个未知功能岛显著影响鼠伤寒沙门菌的致病力,为深入研究这些岛的功能及调控机制奠定了基础。[Objective] To investigate the role of Salmonella genomic islands of unknown functions for pathogenicity and also to identify new islands associated with Salmonella virulence. [Methods] Using Salmonella enteric serovar Typhimurium （S. Typhimurium） ATCC 14028 as wild-type strain, we constructed mutants for seven islands of unknown functions （STM14_0667-0673, 2682-2687, 2885-2891, 3721-3728, 4247-4253, 4823-4828, 5331-5341） by employing the ） λ Red recombinase method. Through invasion assays, macrophage replication assays, and mice experiment, we compared the virulence of the mutant strains to that of the wild-type 14028. [Results] Compared with wild-type strain, A2682-2687 and A5331-5341 significantly decreased their invasion ability to epithelial cells （P〈0.01）; A2682-2687, A2885-2891 and A5331-5341 significantly decreased their replication ability in macrophages, and also showed decreased virulence to mice, with the bacterial counts of mutants in intestine, liver and spleen were less abundant than that of the wild-type strain （P〈0.05）. No significant differences in invasion ability, replication ability, and virulent to mice were observed between wild-type strain and the other four mutant strains （A0667-0673, A3721-3728, A4247-4253 and A4823-4828）. [Conclusions] This study found three islands of unknown functions contributing to S. Typhimurium pathogenicity, and provided powerful tools for the further research on the regulatory systems and functions of these islands.

关 键 词：鼠伤寒沙门菌 未知功能岛 致病性 

分 类 号：R378[医药卫生—病原生物学]