Department of Microbiology and Molecular Biology, Brigham Young University, 893 WIDB, Provo, UT 84602, USA.
Microb Pathog. 2011 Dec;51(6):389-95. doi: 10.1016/j.micpath.2011.08.008. Epub 2011 Sep 24.
The virulence of Yersinia pestis KIM6+ was compared with multiple isolates of Yersinia pseudotuberculosis and Yersinia enterocolitica toward larvae of the greater wax moth Galleria mellonella. Although Y. pestis and Y. pseudotuberculosis were able to cause lethal infection in G. mellonella, these species appeared less virulent than the majority of Y. enterocolitica strains tested. Y. pestis survived primarily within hemocytes of G. mellonella, and induced a strong antibacterial peptide response that lasted for at least 3 days in surviving larvae. Immunization with dead bacteria to induce an antibacterial response led to increased survival of the larvae following infection. Mutant strains lacking the either phoP or oxyR, which were less resistant to antibacterial peptides and hydrogen peroxide respectively, were attenuated and restoration of the wild-type genes on plasmids restored virulence. Our results indicate that the Y. pseudotuberculosis-Y. pestis lineage is not as virulent toward G. mellonella as are the majority of Y. enterocolitica isolates. Further, we have shown that G. mellonella is a useful infection model for analyzing Y. pestis host-pathogen interactions, and antibacterial peptide resistance mediated by phoP and reactive oxygen defense mediated by oxyR are important for Y. pestis infection of this insect.
将鼠疫耶尔森氏菌 KIM6+ 的毒力与多种假结核耶尔森氏菌和小肠结肠炎耶尔森氏菌的分离株进行了比较，这些分离株对蜡螟幼虫的影响。虽然鼠疫耶尔森氏菌和假结核耶尔森氏菌能够导致蜡螟幼虫致命感染，但这些物种的毒力似乎不如大多数测试的小肠结肠炎耶尔森氏菌菌株。鼠疫耶尔森氏菌主要在蜡螟的血细胞内存活，并诱导强烈的抗菌肽反应，在存活的幼虫中至少持续 3 天。用死菌免疫以诱导抗菌反应可导致感染后幼虫的存活率增加。缺乏分别对抗菌肽和过氧化氢的抗性的 phoP 或 oxyR 缺失突变株减弱，并且在质粒上恢复野生型基因可恢复毒力。我们的结果表明，与大多数小肠结肠炎耶尔森氏菌分离株相比，假结核耶尔森氏菌-鼠疫耶尔森氏菌谱系对蜡螟的毒力较低。此外，我们已经表明，蜡螟是分析鼠疫耶尔森氏菌宿主-病原体相互作用的有用感染模型，并且 phoP 介导的抗菌肽抗性和 oxyR 介导的活性氧防御对于该昆虫的鼠疫耶尔森氏菌感染很重要。
