Analysis of the transcriptome of Legionella pneumophila hfq mutant reveals a new mobile genetic element.
Analysis of the transcriptome of Legionella pneumophila hfq mutant reveals a new mobile genetic element.
复制标题
对嗜肺军团菌 hfq 突变体转录组的分析揭示了一种新的可移动遗传元件。
DOI：
10.1099/mic.0.067983-0
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发表时间：
2013
期刊：
影响因子：
--
通讯作者：
Faucher,SebastienP
中科院分区：
文献类型：
--
作者：
Trigui,Hana;Dudyk,Paulina;Sum,Janet;Shuman,HowardA;Faucher,SebastienP
Hfq is a small RNA-binding protein involved in the post-transcriptional regulation of gene expression by affecting the stability of the mRNA and by mediating efficient pairing between small regulatory RNAs and their target mRNAs. InLegionella pneumophila, the aetiological agent of Legionnaires’ disease, mutation ofhfqresults in increased duration of the lag phase and reduced growth in low-iron medium. In an effort to uncover genes potentially regulated by Hfq, the transcriptome of anhfqmutant strain was compared to that of the wild-type. Unexpectedly, many genes located within a 100 kb genomic island, including a section of the previously identified efflux island, were overexpressed in thehfqmutant strain. Since this island contains a putative conjugative system and an integrase, it was postulated that it could be a new integrated mobile genetic element. PCR analysis revealed that this region exists both as an integrated and as an episomal form in the cell population and that it undergoes differential excision in thehfqmutant background, which was further confirmed bytrans-complementation of thehfqmutation. This new plasmid-like element was named pLP100. Differential excision did not affect the copy number of pLP100 at the population level. This region contains a copper efflux pump encoded bycopA, and increased resistance to copper was observed for thehfqmutant strain that was abrogated in the complemented strain. A strain carrying a mutation ofhfqand a deletion of the right side recombination site,attR, showed that overexpression of pLP100 genes and increased copper resistance in thehfqmutant strain were dependent upon excision of pLP100.
