[中国患病猪源致病性大肠杆菌的毒力基因及其与O血清群的关系]

[Virulence genes of pathogenic Escherichia coli from ill pigs in China and their relationship with O-serogroups].

作者信息

Chen Xiang, Zhao Lixiang, Gao Song, Miao Xiaoqing, Jiao Xinan, Liu Xiufan

机构信息

Animal Infectious Disease Laboratory of Ministry of Agriculture, Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou 225009, China.

出版信息

Wei Sheng Wu Xue Bao. 2008 Jul;48(7):857-62.

PMID:18837360

Abstract

OBJECTIVE

We determined the distribution of serogroups and virulence factors among Escherichia coli isolates from pigs with diarrhea and/or edema disease from 10 provinces in China between 1998 and 2007.

METHODS

Three hundred E. coli isolates were serogrouped with O-antisera and detected for genes of enterotoxins, shiga-toxin-two-variant (Stx2e), intimin, K88, K99, 987P, F18 and F41 fimbrial antigens by PCR.

RESULTS

Among 300 isolates, 233 were determined to be placed in serogroups, 50 were unable to be serogrouped, and the rest 17 auto-agglutinated. These isolates distributed in 45 serogroups and 57.1% (133/233) belonged to 5 O serogroups: O149, O107, O139, O93 and O91. Several uncommon O serogroups were discovered. PCR analysis confirmed the genes of est I (STa), est II (STb), elt (LT), stx2e (Stx2e) and eaeA (Intimin) within the isolates. There were six pathotypes of porcine E. coli by their pathogenic factors, namely enterotoxigenic E. coli (ETEC), shiga toxin-producing E. coli (STEC), attaching-effacing E. coli (AEEC), ETEC/ STEC, AEEC/ETEC and AEEC/ETEC/STEC. The correlation between pathotypes and serogroups showed that the combinations of O149/K88/estII, O149/K88/est II+elt, O107/F18/est II, 093/est II and O98/est II were common types in ETEC strains, O139/ F18/stx2e for STEC strains, eaeA gene for AEEC strains, O107/F18/estI+stx2e, O107/F18/estII + stx2e and O116/F18/est I +elt+stx2e for ETEC/STEC strains, 091/est I/eaeA and O107/est I /eaeA for AEEC/ETEC/STEC strains".

CONCLUSION

ETEC was commonly associated with swine colibacillosis, whereas the kinds of enteric E. coli pathogens become more complex in China.

摘要

目的

我们确定了1998年至2007年间从中国10个省份腹泻和/或水肿病猪中分离出的大肠杆菌菌株血清群和毒力因子的分布情况。

方法

用O抗血清对300株大肠杆菌进行血清分型，并用聚合酶链反应（PCR）检测其肠毒素、志贺毒素2变异体（Stx2e）、紧密黏附素、K88、K99、987P、F18和F41菌毛抗原基因。

结果

300株分离株中，233株确定为可分型，50株无法分型，其余17株自动凝集。这些分离株分布于45个血清群，57.1%（133/233）属于5个O血清群：O149、O107、O139、O93和O91。发现了几个不常见的O血清群。PCR分析证实分离株中存在est I（STa）、est II（STb）、elt（LT）、stx2e（Stx2e）和eaeA（紧密黏附素）基因。根据致病因子，猪大肠杆菌有六种致病型，即产肠毒素大肠杆菌（ETEC）、产志贺毒素大肠杆菌（STEC）、黏附-侵蚀性大肠杆菌（AEEC）、ETEC/STEC、AEEC/ETEC和AEEC/ETEC/STEC。致病型与血清群之间的相关性表明，O149/K88/estII、O149/K88/est II+elt、O107/F18/est II、093/est II和O98/est II组合是ETEC菌株中的常见类型，O139/F18/stx2e是STEC菌株中的常见类型，eaeA基因是AEEC菌株中的常见类型，O107/F18/estI+stx2e、O107/F18/estII + stx2e和O116/F18/est I +elt+stx2e是ETEC/STEC菌株中的常见类型，091/est I/eaeA和O107/est I /eaeA是AEEC/ETEC/STEC菌株中的常见类型。