期刊
RESEARCH IN MICROBIOLOGY
卷 161, 期 8, 页码 711-719出版社
ELSEVIER
DOI: 10.1016/J.resmic.2010.07.004
关键词
Protozoa; Ciliates; Conjugation; Escherichia coli
类别
资金
- Akiyama Life Science Foundation
- Kakenhi
- Suhara Memorial foundation
- Asahi Glass foundation of Japan
- Institute for Fermentation, Osaka, Japan
The mechanism underlying bacterial conjugation through protozoa was Investigated. Kanamycin-resistant Escherichia colt SMI0 lambda(+) carrying pRT733 with TnphoA was used as donor bacteria and introduced by conjugation into ciprofloxacin-resistant E. colt clinical isolate recipient bacteria. Equal amounts of donor and recipient bacteria were Mixed together in the presence or absence of protozoa (ciliates, free-living amoebae, myxamoebae) in Page's amoeba saline for 24 h. Transconjugants were selected with Luria broth agar containing kanamycin and ciprofloxacin. The frequency of conjugation was estimated as the number of transconjugants for each recipient. Conjugation frequency in the presence of ciliates was estimated to be approximately 10(-6) but in the absence of ciliates, or in the presence of other protozoa, it was approximately 10(-8). Conjugation also occurred in culture of ciliates at least 2 h after incubation. Successful conjugation was confirmed by the polymerase chain reaction. Addition of cycloheximide or latrunculin B resulted in suppression of conjugation. Heat killing the ciliates or bacteria had no effect on conjugation frequency. Co-localization of green fluorescent protein-expressing E colt and PKH-67-vital-stained E. coli was observed in the same ciliate vesicles, suggesting that both donor and recipient bacteria had accumulated in the same vesicle. In this study, the conjugation frequency of bacteria was found to be significantly higher in vesicles purified from ciliates than those in culture suspension We conclude that ciliates rapidly enhance the conjugation of E. coli strains through bacterial accumulation in vesicles. (C) 2010 Elsevier Masson SAS. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据