[无锡市不同地点冷却水样中军团菌污染状况及分子生物学特征]

[Contamination status and molecular biological characteristics of Legionella in cooling water samples from different places in Wuxi city].

作者信息

Zhang Qi, Chen Rong, Xiao Yong, Liu Bin, Qin Tian, Shao Zhu-Jun, Zhou Wei-Jie

机构信息

Wuxi Center for Disease Control and Prevention, Wuxi 214023, China.

出版信息

Zhonghua Yu Fang Yi Xue Za Zhi. 2012 Mar;46(3):264-8.

PMID:22800600

Abstract

OBJECTIVE

To investigate the contamination state of Legionella in cooling water samples from different places in Wuxi city and reveal the molecular biological characteristics of Legionella strains.

METHODS

112 parallel water samples (500 ml each) were collected from 56 sites in Wuxi city during year 2009 - 2010. The samples were used for Legionella test and quantitative culture. The isolated Legionella strains were used for serotyping, pulsed-field gel electrophoresis (PFGE), sequence-based typing (SBT), and intracellular growth were tested.

RESULTS

The positive proportion of Legionella was 39. 3% (22/56) among all sampling sites. A total of 29 Legionella strains were isolated, and the serotypes include LP1, LP3, LP5 and LP6. LP1 serotype was the major one with a proportion of 65.5% (19/29). 29 Legionella strains got 17 PFGE types. There were 10 SBT types among 10 Legionella strains with different PFGE types. Comparing to LP1 strain (ATCC 33152), WX2011062 (LP6) and WX2011067 (LP5) had strong intracellular growth ability in mouse peritoneal macrophages J774 cell line (the amount of intracellular bacteria on day 0 after infection were (5.5 +/- 1.32) x 10(5), (3.9 +/- 0.60) x 10(5), (7.8 +/- 0.76) x 10(5) CFU/ml, respectively; the amount of intracellular bacteria on day 3 after infection were (58.3 +/- 1.61) x 10(5), (2700.0 +/- 655.74) x 10(5), (3066.7 +/- 208.17) x 10(5) CFU/ml, respectively).

CONCLUSION

The Legionella contamination existed in cooling water samples from different places in Wuxi city. Legionella strains isolated showed high genetic variation. Some Legionella strains had vigorous intracellular growth ability.

摘要

目的

调查无锡市不同地点冷却水样中军团菌的污染状况，揭示军团菌菌株的分子生物学特征。

方法

2009 - 2010年期间从无锡市56个地点采集112份平行水样（每份500 ml）。这些样品用于军团菌检测和定量培养。对分离出的军团菌菌株进行血清分型、脉冲场凝胶电泳（PFGE）、基于序列的分型（SBT），并检测细胞内生长情况。

结果

所有采样点中军团菌阳性比例为39.3%（22/56）。共分离出29株军团菌菌株，血清型包括LP1、LP3、LP5和LP6。LP1血清型为主，占比65.5%（19/29）。29株军团菌菌株获得17种PFGE型。10株具有不同PFGE型的军团菌菌株中有10种SBT型。与LP1菌株（ATCC 33152）相比，WX2011062（LP6）和WX2011067（LP5）在小鼠腹腔巨噬细胞J774细胞系中具有较强的细胞内生长能力（感染后第0天细胞内细菌数量分别为(5.5±1.32)×10⁵、(3.9±0.60)×10⁵、(7.8±0.76)×10⁵ CFU/ml；感染后第3天细胞内细菌数量分别为(58.3±1.61)×10⁵、(2700.0±655.74)×10⁵、(3066.7±208.17)×10⁵ CFU/ml）。