单核细胞增生性李斯特菌分离株的生物学特性研究

Characterization of 6 Listeria Monocytogene isolates obtained from Guangzhou poultry products

对从广州禽产品分离的6株LM进行了药敏试验、pH值的适应范围、动物致病性等生物学特性研究。6株LM分离株对先锋必、氯霉素、卡那霉素、头孢唑啉、庆大霉素等多种药物敏感;而对多黏菌素B、复方新诺明、新生霉素有耐药性。LM分离株在pH值4.0～10.5范围内可存活。以109 CFU剂量感染SPF小鼠、清洁级新西兰兔和健康粤黄鸡,小鼠的致死率达100%,可引起兔结膜炎等症状,但未引起试验鸡的任何不适。6株LM分离株的Hly基因与标准参考株基因相似性达到96.1%以上,说明该基因在LM中较为保守。

Six Listeria Monocytogene isolates were obtained from poultry products in Guangzhou. Anti-microbial resistance, suitable growth pH range and pathogenicity of the isolate were examined. All 6 isolates were sensitive to many drugs including Cefoperazone Sodium, Chloramphenicol, Kanamycin, Cefazolin V, Gentamicin; resistant to Polymyxin B, trimethoprim-sulfamethoxazole, Novobiocin. The isolates could survive in pH 4.0-10.5, and could cause BABL/c mice death with 109 CFU dose by intraperitoneal infection. The same dose of the isolates could cause conjunctivitis in New Zeeland rabbits by injection via eYe-drop route. The same dose to healthy Guangdong Huang chickens by intramuscular injection did not cause clinical signs. These hly gene nucleotide sequences had a high homology of 96.1%-100% with C53005, C53003 and DQ054589,DQ844148, EF182456 in GenBank database, so hly gene was conserved in LM.