The arms race between bacteria and phages led to the emergence of a variety of genetic systems used by bacteria to defend against viral infection, some of which were repurposed as powerful biotechnological tools. While numerous defense systems have been identified in genomic regions termed defense islands, it is believed that many more remain to be discovered. Here, we show that P2-like prophages and their P4-like satellites have genomic hotspots that represent a significant source of novel anti-phage systems. We validate the defense activity of 14 systems spanning various protein domains and describe PARIS, an abortive infection system triggered by a phage-encoded anti-restriction protein. Immunity hotspots are present across prophages of distant bacterial species, highlighting their biological importance in the competition between bacteria and phages.

中文翻译：

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噬菌体编码的细菌免疫系统热点

细菌和噬菌体之间的军备竞赛导致了细菌用来防御病毒感染的各种遗传系统的出现，其中一些被重新用作强大的生物技术工具。尽管在被称为防御岛的基因组区域中已经确定了许多防御系统，但人们相信还有更多的待发现。在这里，我们显示P2类噬菌体及其P4类卫星具有基因组热点，这些热点代表了新型抗噬菌体系统的重要来源。我们验证了跨越各种蛋白质域的14个系统的防御活性，并描述了PARIS，这是一种由噬菌体编码的抗限制性蛋白触发的流产感染系统。免疫热点遍布远处的细菌物种，