大肠埃希菌O157：H7志贺毒素Ⅱ变种的分布

Study on detecting Stx2 variation in escherichia coli O157:H7 with gene probe

摘要:
目的了解徐州地区E.coliO157:H7分离菌株Stx2毒素变种Stx2vha在人及畜禽中的携带分布情况。
方法用特异性探针Southern杂交检测菌株中是否携带Stx2vha毒素变种。
结果 66株分离株中35株为Stx2vha毒素变种阳性, 占53%, 13株为Stx2原毒素阳性, 占19.7%, 17株为Stx2毒素阴性, 占25.8%, 另有1株不同于其它菌株是否为新的毒素变种需进一步确证。35株Stx2vha阳性菌株在羊、病人、牛、猪、鸡的分离率分别为37.1%, 25.7%, 17.1%, 11.4%, 4.5%。
结论含有Stx2vha毒力基因菌株是徐州地区O157:H7菌株的优势菌型, 主要宿主动物为羊。

Abstract:
Objective To understand the distribution of Stx2 variation, Stx2vha in E.coli O157:H7 isolated from some principal host animals and human in Xuzhou.
Methods Stx2 variation, Stx2vha was tested using Southern-blot of particularial probe.
Results Among the 66 E.coli O157:H7 isolates examined, 35 was positive of Stx2vha(53%), 13 was positive of Stx2(19.7%)and 17 was negative of Stx2 and Stx2vha(25.8%).One was untyped because its band was different from the others.The 35 with Stx2vha was isolated from feces of human(9, 25.7%)、sheep(13, 37.1%)、cattle(6, 17.1%)、pigs(4, 11.4%)and chickens(3, 4.5%)respectively.
Conclusion The isolate with Stx2vha virulence gene were the predominant type of E.coli O157:H7 in Xuzhou, and the prinicipal host was sheep.