冷冻鸡肉中单核细胞增生李斯特菌2个分离株的毒力及毒力相关因素研究  

Virulence of Two Strains of Listeria monocytogenes Isolated from Frozen Chicken and Analysis of Virulence-associated Factors

作　　者：李楠 阮婷玉 孙天浩 康立超[2] 彭健 王静[1] 马勋[1] LI Nan;RUAN Ting-yu;SUN Tian-hao;KANG Li-chao;PENG Jian;WANG Jing;MA Xun(College of Animal Science and Technology,Shihezi University,Shihezi,Xinjiang,832003,China;Analysis and Testing Center,Xinjiang Academy of Agricultural and Reclamation Science,Shihezi,Xinjiang,832000,China)

机构地区：[1]石河子大学动物科技学院,新疆石河子832003 [2]新疆农垦科学院分析测试中心,新疆石河子832003

出　　处：《动物医学进展》2022年第3期11-15,共5页Progress In Veterinary Medicine

基　　金：国家自然科学基金项目(31860712);动物疾病防控兵团重点实验室开放课题(2020BTDJ05);省部共建绵羊遗传改良与健康养殖国家重点实验室开放课题(MYSKLKF201905);江苏省人兽共患病重点实验室开放项目(R1901)。

摘　　要：以鸡胚为感染动物,检测2株冷冻鸡肉单核细胞增生李斯特菌(LM)的鸡胚半数致死量(LD_(50))、鸡胚肝脏指数、确定其毒力,同时检测毒力基因、溶血价、生物被膜形成能力,进行毒力相关因素分析。结果显示,与PBS组和无害李斯特菌(L.innocua)组相比,LM873与LM925均能致死鸡胚,鸡胚LD_(50)分别为4.733和1.533;鸡胚肝脏指数均明显大于PBS组和L.innocua组(P<0.05);8个毒力基因除lmo1116仅存在于LM925中外,其余基因分布一致;LM873与LM925的溶血价分别为2^(3)和2^(4);在生物被膜的形成过程中,同一时间段LM925较LM873的生物被膜更致密;LM925在6、8、10、12、24、36 h生物被膜的形成能力显著高于LM873(P<0.05),且在10、24、36 h时差异极显著(P<0.01),但是LM873与L.innocua生物被膜的形成没有明显差异。综上所述,2株冷冻鸡肉LM分离株均能致死鸡胚,且LM925的毒力强于LM873;溶血价素活性及毒力基因分布与菌株毒力呈正相关性。In this study,chicken embryos were used as experimental animals.The half lethal dose(LD_(50))and liver index of chicken embryos infected by two LM strains were detected to determine virulence of LM.Meanwhile,virulence genes,hemolytic titer and biofilm formation ability were detected to analyze the correlation between these factors and virulence.The results showed that compared with PBS group and Listeria innocua group,both LM873 and LM925 could cause chicken embryo death,and the LD_(50) were 4.733 and 1.533,respectively.The liver indexes of chicken embryos infected with LM873 and LM925 were significantly higher than that of PBS group and L.innocua group(P<0.05).Among the eight virulence genes,lmo1116 only existed in LM925,and the other genes could be detected in both strains.The hemolytic titers of LM873 and LM925 were 2^(3) and 2^(4),respectively.In the process of biofilm formation,the biofilm morphology of LM925 was denser than that of LM873 at the same time.The biofilm formation ability of LM925 at 6 h,8 h,10 h,12 h,24 h,36 h is higher than that of LM873,the difference is significant(P<0.05),and the difference is extremely significant at 10 h,24 h,36 h(P<0.01).However,there was no significant difference in biofilm formation between LM873 and L.innocua.In conclusion,both LM isolates from frozen chicken could cause the chicken embryos death,and the virulence of LM925 was stronger than that of LM873.Hemolytic activity and virulence gene distribution were positively correlated with virulence.

关 键 词：单核细胞增生李斯特菌 半数致死量 毒力基因 溶血能力 生物被膜 

分 类 号：S852.61[农业科学—基础兽医学]