Genes coding for enterotoxins and verotoxins in porcine Escherichia coli strains belonging to different O:K:H serotypes: Relationship with toxic phenotypes
Genes coding for enterotoxins and verotoxins in porcine Escherichia coli strains belonging to different O:K:H serotypes: Relationship with toxic phenotypes
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DOI：
10.1128/jcm.35.11.2958-2963.1997
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发表时间：
1997-11-01
影响因子：
9.4
通讯作者：
Blanco, J
中科院分区：
文献类型：
--
作者：
Blanco, M;Blanco, JE;Blanco, J
74 E对从西班牙腹泻或水肿病仔猪中分离的大肠杆菌菌株进行血清分型，并通过表型（Vero细胞试验和幼鼠试验）和基因型（菌落杂交和PCR）方法检测热不稳定（LT）和热稳定（ST）肠毒素（LT-I、LT-II、STaH、STaP和STb）和verotoxins（VT 1、VT 2和VT 2 v VTe）的产生。在一般情况下，一个很好的相关性，发现与PCR方法获得的结果和那些确定与生物测定。杂交中使用的DNA探针也显示出与表型结果非常一致，除了VT 1探针最初产生10个假阳性反应。PCR检测到的STb基因（58株）是最常见的基因，其次是STa基因（46株）、LT基因（19株）、VT 2 v基因（11株）和VT 1基因（1株）。显然，在西班牙，三种血清病理型是主要的：（i）0149：K91：H10 K88（+）LT-1 + STb+（ii）0141：K85 ab：H-P987（+）STaP+，和（iii）0138：K81：H14或H-STaP+ VT 2 v（+）。结论：PCR是一种快速、特异、实用的方法，可用于临床和流行病学研究中肠毒素和VT基因的鉴定。
Seventy-four E. coli strains isolated from piglets with diarrhea or edema disease in Spain were serotyped and examined for production of heat-labile (LT) and heat-stable (ST) enterotoxins (LT-I, LT-II, STaH, STaP, and STb) and verotoxins (VT1, VT2, and VT2v VTe) by phenotypic (Vero cell assay and infant mouse test) and genotypic (colony hybridization and PCR) methods. In general, an excellent correlation was found between the results obtained with a PCR approach and those determined with biological assays. DNA probes used in the hybridization also showed a very good agreement with phenotypic results, with the exception of a VT1 probe that initially produced 10 false-positive reactions. The gene coding for STb (58 strains) was the most prevalent gene detected by PCR, followed by those coding for STa (46 strains), LT (19 strains), VT2v (11 strains), and VT1 (1 strain). Apparently, in Spain three seropathotypes are predominant: (i) 0149:K91:H10 K88(+) LT-I+ STb+ (ii) 0141:K85ab:H- P987(+) STaP+, and (iii) 0138:K81:H14 or H-STaP+ VT2v(+). We conclude that PCR is a fast, specific, and practical method for the identification of enterotoxin and VT genes in clinical and epidemiological studies.