Alibaud Laeticia, Köhler Thilo, Coudray Alice, Prigent-Combaret Claire, Bergeret Evelyne, Perrin Jackie, Benghezal Mohammed, Reimmann Cornelia, Gauthier Yves, van Delden Christian, Attree Ina, Fauvarque Marie-Odile, Cosson Pierre
Département de Physiologie Cellulaire et Métabolisme, Université de Genève, Centre Médeical Universitaire, 1 rue Michel Servet, CH-1211 Geneva 4, Switzerland.
Cell Microbiol. 2008 Mar;10(3):729-40. doi: 10.1111/j.1462-5822.2007.01080.x. Epub 2007 Nov 27.
The human pathogen Pseudomonas aeruginosa has been shown previously to use similar virulence factors when infecting mammalian hosts or Dictyostelium amoebae. Here we randomly mutagenized a clinical isolate of P. aeruginosa, and identified mutants with attenuated virulence towards Dictyostelium. These mutant strains also exhibited a strong decrease in virulence when infecting Drosophila and mice, confirming that P. aeruginosa makes use of similar virulence traits to confront these very different hosts. Further characterization of these bacterial mutants showed that TrpD is important for the induction of the quorum-sensing circuit, while PchH and PchI are involved in the induction of the type III secretion system. These results demonstrate the usefulness and the relevance of the Dictyostelium host model to identify and analyse new virulence genes in P. aeruginosa.
先前已表明，人类病原体铜绿假单胞菌在感染哺乳动物宿主或盘基网柄菌变形虫时会使用相似的毒力因子。在此，我们对一株临床分离的铜绿假单胞菌进行随机诱变，并鉴定出对盘基网柄菌毒力减弱的突变体。这些突变菌株在感染果蝇和小鼠时也表现出毒力的大幅下降，证实铜绿假单胞菌利用相似的毒力特性来应对这些截然不同的宿主。对这些细菌突变体的进一步表征表明，色氨酸合酶β亚基（TrpD）对群体感应回路的诱导很重要，而吩嗪羧酸水解酶（PchH）和吩嗪羧酸异构酶（PchI）参与III型分泌系统的诱导。这些结果证明了盘基网柄菌宿主模型在鉴定和分析铜绿假单胞菌新毒力基因方面的实用性和相关性。
