VI型分泌系统(type VI secretion system,T6SS)具有转运效应蛋白分子到多种类型靶细胞的能力,广泛存在于革兰氏阴性菌,其结构复杂。当前T6SS结构模型表明其装置至少包含两个复合物:细胞膜跨膜相关装置和动态的噬菌体样结构。本文主要围绕T6SS分泌装置的结构、结构元件相互作用功能以及影响装置表达和活性的条件和信号来进行简要综述。
[Objective] This study aimed to explore the presence of typeⅠpili(fim C gene) and P pili(pap C gene) and identify the serotype of pathogenic E.coli isolated from chickens in the Jidong Area.[Method]TypeⅠpili(fim C gene) and P pili(pap C gene) were detected by PCR.The serotype was identified by conventional agglutination test.[Result]The results showed that 100% of chicken-derived E.coli strains expressed typeⅠpili(fim C gene);39.1%(9/23) of chicken-derived E.coli strains expressed P pili(pap C gene).In addition,23 isolates of chicken-derived E.coli were assigned to 14 O serotypes,including O78,O93,O 45,O101,O38,O88,O24,O1,O163,O53,O15,O87,O34 and O29,among which O78 was the dominant serotype that accounted for 42.8%(6/14) of the total strain number.[Conclusion]Chicken-derived E.coli strains in the Jidong Area belonged to 14 serotypes,and O78 was the dominant serotype;83.3% of O78 serotype E.coli strains expressed both typeⅠpili and P pili.
