单核细胞增生李斯特菌（ Listeria monocytogenes，Lm）是李斯特菌病的病原细菌。用Lm野生株EGDe、弱毒株ΔprfA、毒力回复株＋prfA和高毒株＋prfA*喂饲模式生物秀丽隐杆线虫N2，并以线虫的良好食源大肠埃希菌OP50以及非致病的无害李斯特菌（ Listeria innocua）作为对照，检测Lm对线虫发育周期、寿命和产卵数的影响。结果显示：当以无害李斯特菌、Lm野生株以及PrfA突变株为食时，线虫的产卵数虽有所下降，但线虫不仅能够正常产卵，而且其发育周期和寿命均较以OP50为食时显著延长（P≤0．05）；线虫体表和消化道中均可检测到大量李斯特菌，但粪便中的活菌数极少。以上结果说明Lm不能杀死秀丽隐杆线虫，对线虫也没有显著致病性，不适合作为研究Lm致病机制的模型；Lm可在线虫体表和消化道存在，暗示Lm可借助线虫在土壤环境中生存和传播。%Lsi tre ia monocytogenes ( Lm) is a pathogenic bacterium of listeriosis.In this study wild type of Lm EGDe, attenuated strainΔprfA, PrfA complementary strain +prfA, and a highly virulent strain +prfA*were fed respectively to model organism of Caenorhabditis elegans (Ce) N2, at the same time, fine food resource of E.coli OP50 and non-pathogenic and unharmful L.innocua was also fed to the model of Ce as a control, to determine the effect of Lm on the development circle, life-span and brood of C.elegans The results showed that when fed on unharmful L.innocua, wild-type Lm EGDe and its PrfA mutant strains, although the brood was slightly decreased, however, the nematode not only could normally oviposit, but also the development period and life-span of C.elegans were significantly extend-ed (P≤0.05) as compared with those fed on E.coli Op50.Furthermore, a large number of live Lm cells were detec-ted from the worms'surface and digestive tract, but only a few bacteria were detected in the worms'excrements.The a-bove results indicated that Lm neither can kill Ce nor have significant pathogenicity against Ce, therefore, C.elegans is not a suitable model to study Listeria pathogenicity.C.elegans can exist in Lm body surface and digestive tracts, suggested that Lm could exist and spreading in soil environment with the aid of nematode.
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