期刊论文

中文

食品科学

1002-6630

2014

35

15

151-155

10.7506/spkx1002-6630-201415031

国家高技术研究发展计划(863计划)项目(2012AA101703-3) 教育部留学回国人员科研启动基金项目(教外司留20111139) 湖北省教育厅优秀中青年人才计划项目(Q20111710) 武汉市科技局国际科技合作计划项目(2013030409020113)

本校为第一机构

1株肠出血性大肠杆菌O157:H7变种EC169菌株,携带stx基因但不表达志贺毒素。通过高效热不对称交错聚合酶链式反应(high-efficiency thermal asymmetric interlaced polymerase chain reaction, hiTAIL-PCR) hiTAIL-PCR扩增得到EC169stx_1及其上游核苷酸片段并克隆测序,结果表明:EC169 q基因与标准株sakai g基因相比存在6个SNP位点。通过PCR扩增O157:H7高毒株EC150q基因全长,并构建表达载体pkk223-q分别转化EC169和低毒株EC157。反转录荧光定量PCR实验结果表明,外源g基因在EC169和EC157重组菌中可高效表达,并引起EC157stx转录水平上调,但EC169重组菌stx转录水平不变。反向乳胶凝集实验结果亦证实E...

An enterohemorrhagic Escherichia coli(EHEC) O157: H7 strain EC169 carrying both stx1 and stx2 genes but not producing Shiga toxins was used in this study to investigate the reason for these characteristics. The stx1 gene and its upstream region from EC169 were amplified by hiTAIL-PCR. Sequencing data showed that EC169 q gene had 6 single nucleotide polymorphism(SNP) sites compared with the corresponding region of the typical strain sakai. A highly virulent O157:H7 strain EC150 and a hypovirulent O157: H7 strain EC157 were tested in this study. The full length of EC150 q gene was amplified and ...