摘要
采用血清学、ＰＣＲ技术、生化反应、药敏试验、Ｖｅｒｏ细胞毒素测定等方法，对分离到的７株肠出血性大肠杆菌Ｏ１５７∶Ｈ７菌株进行了综合分析。表明试验菌株用Ｏ１５７单克隆抗体和Ｏ１５７∶Ｈ７血清在做玻片凝集时，模式均较好；Ｈ７血清做试管定量凝集试验时亦均达到要求的稀释度以上；特异性ＰＣＲ技术检查时，测得１株试验菌株带有毒力基因；经全自动微生物鉴定系统检测２８种生化反应时，有１８种生化反应与９３３菌株完全相同，其余１０种生化反应各有不同，其中与９３３菌株有５种生化反应不同的有四株，４、３、１种生化反应不同的各一株。未发现与９３３菌株生化特性完全相等的菌株，亦未发现试验菌株间生化特性完全相同的。１２种常用抗菌素药敏试验显示对氯霉素、丁胺卡那霉素、菌必治均为敏感。对其它抗菌素均有不同程度的耐药。
Objective:To understand the biological properties of EHEC O157∶H7 strains isolated from Hangzhou in 1997.Methods:The techniques,including serology agglutination test,PCR,biochemical reaction assay,Vero toxin assay and antibiotic susceptibility test,were used to analyze the biological properties of 7 strains of EHEC O157∶H7.Results:Both O157 monoclonal antibody and polyclonal anti-serum can agglutinate all of strains in all slide agglutination test,and quantitative tube agglutination test to H 7 anti-serum can reach higher titer in all strains.Hemolysin gene is detected in one strain by specific PCR.The results of 28 biochemical characteristics tested by automatic microorganisms identification system show:18 biochemical characteristics of 7 strain are the same as those of EHEC O157∶H7 strain 933 and the other 10 biochemical characteristics are not identical with those of stran 933;In all of 28 biochemical characteristics none of 7 strains is identical with strain 933 and there are not identical biochemical characteristics among 7 strains.In 12 routine antibiotics susceptibility test,all of strains are susceptible to chloramphenicaol,amikacin,and coftriaxone sodium, but resistible to the other antibiotics in various degress.Conclusion:The serological results of 7 strains tested in this paper are optimal but there is not any identical mode of biochemical characteristic,and some biochemical characteristic may vary easily.
关键词
出血性大肠杆菌
生化特性
Vero细胞毒素
Enterohemorrhagic Escherichia coli (EHEC)O157∶H7 Biochemical characteristic Vero toxin
