珠江口霍乱弧菌毒力相关基因监测及分布研究

[Surveillance program on and the distribution related to the virulence-associated genes of Vibrio cholerae in estuary of Pearl River].

作者信息

Li Bai-sheng, Wang Duo-chun, Tan Hai-ling, Ke Bi-xia, Chen Jing-diao, He Dong-mei, Liu Mei-zhen, Deng Xiao-ling, Ke Chang-wen, Kan Biao

机构信息

Institute of Pathogenic Microorganisms, Guangdong Provincial Center for Diseases Control and Prevention, Guangzhou, China.

出版信息

Zhonghua Liu Xing Bing Xue Za Zhi. 2011 Dec;32(12):1242-6.

PMID:22336609

Abstract

OBJECTIVE

To understand the distribution, molecular characteristics and virulence genes of the O1 and O139 Vibrio cholerae isolates from the Pearl River Estuary water.

METHODS

Vibrio cholerae isolates collected from the Pearl River estuary waters from January 2009 to December 2010, were tested by PCR for eight virulence-related genes, including cholera toxin (ctxA), zonula occludens toxin (zot), accessory cholera enterotoxin (ace), hemolysin (hlyA), toxin-coregulated pilus (tcpA), outer membrane protein (ompU), and the regulatory protein genes (tcpI, toxR). Genetic relation was assessed by pulsed-field gel electrophoresis (PFGE) and the patterns were clustered by BioNumerics.

RESULTS

From 1152 aquatic samples, 69 isolates were identified, including 41 Inaba, 18 Ogawa and 10 O139. All the isolates showed ctxA negative, while the hlyA and toxR genes were positive in all the isolates. 34.15% (14/41) of the Inaba strains were hlyA(+) toxR(+) ompU(+) ace(+) zot(+) tcpI(+), while 66.67% (12/18) belonged to Ogawa strains and 70% (7/10) of the O139 strains were hlyA(+) toxR(+). Through PFGE analysis, the O1 isolates formed three clusters in this study. The patterns of O1 isolates differed widely, with the similarity as 72.8% - 100.0%, while the patterns of O139 isolates having the similarity of 69.9% - 95.5%.

CONCLUSION

The non-toxigenic O1 and O139 V. cholerae had a wide distribution in the environment of Pearl River estuary water during the non-epidemic period of cholera. All the aquatic isolates presented diversities on the related virulent genes.

摘要

目的

了解珠江口水体中O1群和O139群霍乱弧菌分离株的分布、分子特征及毒力基因情况。

方法

对2009年1月至2010年12月从珠江口水域采集的霍乱弧菌分离株，采用聚合酶链反应（PCR）检测8种与毒力相关的基因，包括霍乱毒素（ctxA）、小带连接毒素（zot）、辅助霍乱肠毒素（ace）、溶血素（hlyA）、毒素共调节菌毛（tcpA）、外膜蛋白（ompU）以及调节蛋白基因（tcpI、toxR）。通过脉冲场凝胶电泳（PFGE）评估遗传关系，并使用BioNumerics软件对电泳图谱进行聚类分析。

结果

从1152份水样中鉴定出69株分离株，其中稻叶型41株、小川型18株、O139群10株。所有分离株ctxA基因均为阴性，而hlyA和toxR基因均为阳性。稻叶型菌株中34.15%（14/41）为hlyA(+) toxR(+) ompU(+) ace(+) zot(+) tcpI(+)，小川型菌株中66.67%（12/18）为此类型，O139群菌株中70%（7/10）为hlyA(+) toxR(+)。通过PFGE分析，本研究中的O1群分离株形成了3个聚类。O1群分离株的图谱差异较大，相似性为72.8% - 100.0%，而O139群分离株图谱的相似性为69.9% - 95.5%。