Prophages are widely spread among bacterial genomes, and they can have positive or negative effects on their hosts. A key aspect in the study of prophages is the discovery of their induction signals. Prophage induction can occur by inactivating a phage transcriptional repressor, which is responsible for maintaining the lysogenic state. This repressor can be inactivated through the bacterial SOS response. However, the induction signals for numerous prophages do not involve the SOS system, and therefore significant efforts are needed to identify these conditions. Similarly, curing bacterial strains of inducible prophages is a tedious process, requiring the screening of several colonies. Here, we investigated whether transcriptional silencing of a prophage repressor using CRISPR interference (CRISPRi) would lead to prophage induction. Using Escherichia coli phages λ and P2 as models, we demonstrated the efficiency of CRISPRi for prophage induction and for curing lysogenic strains of their prophages.

中文翻译：

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使用 CRISPR 干扰诱导和消除原噬菌体

原噬菌体广泛分布在细菌基因组中，它们可以对宿主产生积极或消极的影响。前噬菌体研究的一个关键方面是发现它们的诱导信号。可以通过使负责维持溶原状态的噬菌体转录抑制因子失活来诱导噬菌体。这种阻遏物可以通过细菌 SOS 反应失活。然而，许多前噬菌体的诱导信号不涉及 SOS 系统，因此需要大量努力来识别这些条件。同样，治愈诱导型前噬菌体的细菌菌株是一个繁琐的过程，需要筛选几个菌落。在这里，我们研究了使用 CRISPR 干扰 (CRISPRi) 的前噬菌体阻遏物的转录沉默是否会导致前噬菌体诱导。使用大肠杆菌噬菌体 λ 和 P2 作为模型，我们证明了 CRISPRi 对前噬菌体诱导和治疗其前噬菌体的溶原菌株的效率。