The oxygen- and iron-dependent sigma factor pvdS of Pseudomonas aeruginosa is an important virulence factor in experimental infective endocarditis.
The oxygen- and iron-dependent sigma factor pvdS of Pseudomonas aeruginosa is an important virulence factor in experimental infective endocarditis.
复制标题
铜绿假单胞菌的氧和铁依赖性σ因子pvdS是实验性感染性心内膜炎的重要毒力因子。
DOI：
10.1086/315338
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发表时间：
2000
期刊：
影响因子：
--
通讯作者：
Bayer,AS
中科院分区：
文献类型：
--
作者：
Xiong,YQ;Vasil,ML;Johnson,Z;Ochsner,UA;Bayer,AS
在铜绿假单胞菌中，pvdS是一个关键的氧（O2）依赖性位点，调节许多毒力基因的表达，包括toxA（编码外毒素A的产生）。为了确定不同氧张力对假单胞菌毒力的体内作用，在兔主动脉和三尖瓣心内膜炎模型（分别代表体内需氧和微需氧条件）中比较了2种敲除突变株Δ pvd和ΔtoxA及其亲本菌株PA01。在主动脉心内膜炎中，赘生物、肾脏和脾脏中的Δ pvds密度显著低于PA01（P<0.01）。相反，在三尖瓣心内膜炎中，在这些相同靶组织中，Δ pvd和PA01组织密度之间没有显著差异。Δ toxA突变体在靶组织内增殖的程度与亲本菌株相同。因此，pvdS（而不是toxA）似乎是最佳毒力所必需的。铜绿假单胞菌，特别是在优先暴露于高O2张力的组织中（例如，主动脉赘生物）。
InPseudomonas aeruginosa, pvdS, a key oxygen (O2)-dependent locus, regulates expression of a number of virulence genes, includingtoxA(which encodes exotoxin A production). To define the in vivo role of differing O2tensions on pseudomonal virulence, 2 knockout mutants, ΔpvdSand ΔtoxA, were compared with their parental strain, PA01, in rabbit aortic and tricuspid endocarditis models (representing aerobic vs. microaerobic conditions in vivo, respectively). In aortic endocarditis, ΔpvdSdensities were significantly less than those of PA01 in vegetations, kidneys, and spleen (P< .01). In contrast, in tricuspid endocarditis, there were no significant differences between ΔpvdSand PA01 tissue densities in these same target tissues. The ΔtoxAmutant proliferated within target tissues to the same extent as the parental strain. Thus,pvdS(but nottoxA) appears to be required for optimal virulence ofP. aeruginosa, particularly in tissues preferentially exposed to high O2tensions (e.g., aortic vegetations).