Pseudomonas aeruginosa utilises its type III secretion system to kill the free-living amoeba Acanthamoeba castellanii
Pseudomonas aeruginosa utilises its type III secretion system to kill the free-living amoeba Acanthamoeba castellanii
复制标题
DOI：
10.1111/j.1550-7408.2008.00311.x
复制
发表时间：
2008-05-01
影响因子：
2.2
通讯作者：
Sandstrom, Gunnar
中科院分区：
文献类型：
--
作者：
Abd, Hadi;Wretlind, Bengt;Sandstrom, Gunnar
铜绿假单胞菌是一种自由生活的常见环境细菌。它是一种机会性和医院病原体，造成严重的人类健康问题。为了克服其捕食者，如巨噬细胞和环境吞噬细胞，它利用不同的生存策略，如形成小菌落和通过III型分泌系统（TTSS）介导的毒素产生。本研究旨在通过共培养、活菌计数、伊红染色、电镜观察、凋亡检测和统计分析来研究铜绿假单胞菌PA103与卡氏阿米巴的TTSS效应蛋白的相互作用。结果表明，铜绿假单胞菌PA103可诱导细胞坏死和凋亡，从而杀死A.通过TTSS效应蛋白ExoU、ExoS、ExoT和ExoY的作用，相比之下，单独培养的阿米巴和与缺乏已知的四种TTSS效应蛋白的铜绿假单胞菌PA 103共培养的阿米巴没有被杀死。结果与铜绿假单胞菌是一种严格的细胞外细菌，需要TTSS才能在环境中生存一致，因为TTSS效应蛋白能够杀死其真核捕食者，如阿米巴。
Pseudomonas aeruginosa is a free-living and common environmental bacterium. It is an opportunistic and nosocomial pathogen causing serious human health problems. To overcome its predators, such as macrophages and environmental phagocytes, it utilises different survival strategies, such as the formation of microcolonies and the production of toxins mediated by a type III secretion system (TTSS). The aim of this study was to examine interaction of TTSS effector proteins of P. aeruginosa PA103 with Acanthamoeba castellanii by co-cultivation, viable count, eosin staining, electron microscopy, apoptosis assay, and statistical analysis. The results showed that P. aeruginosa PA103 induced necrosis and apoptosis to kill A. castellanii by the effects of TTSS effector proteins ExoU, ExoS, ExoT, and ExoY. In comparison, Acanthamoeba cultured alone and co-cultured with P. aeruginosa PA103 lacking the known four TTSS effector proteins were not killed. The results are consistent with P. aeruginosa being a strict extracellular bacterium that needs TTSS to survive in the environment, because the TTSS effector proteins are able to kill its eukaryotic predators, such as Acanthamoeba.