(p)ppGpp synthetases regulate the pathogenesis of zoonotic Streptococcus suis
(p)ppGpp synthetases regulate the pathogenesis of zoonotic Streptococcus suis
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(p)ppGpp 合成酶调节人畜共患猪链球菌的发病机制
DOI：
10.1016/j.micres.2016.05.007
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发表时间：
2016
影响因子：
6.7
通讯作者：
Zhou Rui
中科院分区：
文献类型：
--
作者：
Zhu Jiawen;Zhang Tengfei;Su Zhipeng;Li Lu;Wang Dong;Xiao Ran;Teng Muye;Tan Meifang;Zhou Rui
（p）ppGpp介导的严格反应是细菌的主要适应机制之一，细菌对环境的适应能力与细菌病原体的发病机制有关。在人畜共患病原性猪链球菌中，存在两种（p）ppGpp合成酶，RelA和RelQ。目的探讨（p）ppGpp/（p）ppGpp合成酶在S. suis，比较了[（p）ppGpp 0]突变株ΔrelAΔ relQ与其亲本菌株的表型。光学显微镜和电子显微镜观察表明，突变株的碳链长度比亲本菌株长。破坏relA和relQ可导致对HEp-2细胞的粘附和侵袭能力降低，对血杀伤和吞噬的敏感性增加。小鼠感染实验表明，该突变株在体内致弱，易于清除。定量逆转录PCR（qRT-PCR）分析表明，突变株中与形态和毒力相关的基因表达下调。我们的研究表明，（p）ppGpp合成酶或（p）ppGpp可以调节这种重要的人畜共患病病原体的发病机制。
(p)ppGpp-mediated stringent response is one of the main adaption mechanism in bacteria, and the ability to adapt to environment is linked to the pathogenesis of bacterial pathogens. In the zoonotic pathogenStreptococcus suis, there are two (p)ppGpp synthetases, RelA and RelQ. To investigate the regulatory functions of (p)ppGpp/(p)ppGpp synthetases on the pathogenesis ofS. suis, the phenotypes of the [(p)ppGpp0] mutant ΔrelAΔrelQand its parental strain were compared. Light and electron microscopy observation showed that the mutant strain had a longer chain-length than its parental strain. Disruption ofrelAandrelQled to decreased adhesive and invasive ability to HEp-2 cells, and increased sensitivity to the blood killing and phagocytosis. Mouse infection experiments showed that the mutant strain was attenuated and easier to be cleaned upin vivo. Quantitative reverse transcription PCR (qRT-PCR) analysis indicated that the expressions of virulence related genes involving in morphology and virulence were down-regulated in the mutant strain. Our study demonstrated that the (p)ppGpp synthetases or (p)ppGpp can regulate the pathogenesis of this important zoonotic pathogen.