Transcriptomic analysis of Shiga-toxigenic bacteriophage carriage reveals a profound regulatory effect on acid resistance in Escherichia coli.
Transcriptomic analysis of Shiga-toxigenic bacteriophage carriage reveals a profound regulatory effect on acid resistance in Escherichia coli.
复制标题
志贺毒素噬菌体托架的转录组分析揭示了对大肠杆菌中酸耐药性的深刻调节作用。
DOI：
10.1128/aem.02034-15
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发表时间：
2015-12
影响因子：
4.4
通讯作者：
Allison HE
中科院分区：
文献类型：
--
作者：
Veses-Garcia M;Liu X;Rigden DJ;Kenny JG;McCarthy AJ;Allison HE
志贺菌噬菌体转化类志贺菌，赋予宿主产生滋贺毒素的能力。关于这些细菌携带的大多数基因的功能或溶原性对大肠杆菌宿主的影响知之甚少。在这里，我们使用新一代测序比较E。感染Stx噬菌体的大肠杆菌菌株，在引发细菌SOS应答之前和之后，启动噬菌体的裂解周期。我们能够区分溶原性和溶解性周期中表达的噬菌体基因，并且我们描述了由于Stx噬菌体携带而在细菌宿主中发生的转录变化。已经鉴定了谷氨酸脱羧酶（GAD）操纵子的上调，通过逆转录定量PCR（RT-qPCR）证实，我们使用表型测定来建立Stx原噬菌体赋予E. coli宿主。已知的噬菌体调节因子在E. coli中，并对重组菌株进行了耐酸性检测。噬菌体编码的转录调节因子CII被确定为溶原细胞中酸反应的控制器。感染E.大肠杆菌O 157菌株，其中整合的Stx原噬菌体被预先去除，显示出增加的耐酸性与非致突变性噬菌体，E124 B感染后。除了证明Stx噬菌体携带和E.大肠杆菌的耐酸性，其影响的生存后摄入，数据集提供了一些其他潜在的见解的影响，拟杆菌噬菌体携带的生物学大肠杆菌。杆菌
Shiga-toxigenic bacteriophages are converting lambdoid phages that impart the ability to produce Shiga toxin to their hosts. Little is known about the function of most of the genes carried by these phages or the impact that lysogeny has on the Escherichia coli host. Here we use next-generation sequencing to compare the transcriptomes of E. coli strains infected with an Stx phage, before and after triggering of the bacterial SOS response that initiates the lytic cycle of the phage. We were able to discriminate between bacteriophage genes expressed in the lysogenic and lytic cycles, and we describe transcriptional changes that occur in the bacterial host as a consequence of Stx phage carriage. Having identified upregulation of the glutamic acid decarboxylase (GAD) operon, confirmed by reverse transcription-quantitative PCR (RT-qPCR), we used phenotypic assays to establish the ability of the Stx prophage to confer a greater acid resistance phenotype on the E. coli host. Known phage regulators were overexpressed in E. coli, and the acid resistance of the recombinant strains was tested. The phage-encoded transcriptional regulator CII was identified as the controller of the acid response in the lysogen. Infection of an E. coli O157 strain, from which integrated Stx prophages were previously removed, showed increased acid resistance following infection with a nontoxigenic phage, ϕ24B. In addition to demonstrating this link between Stx phage carriage and E. coli acid resistance, with its implications for survival postingestion, the data set provides a number of other potential insights into the impact of lambdoid phage carriage on the biology of E. coli.