微生物防御系统是生物技术创新与发展的重要工具库,细菌限制性内切酶的发现催生了现代分子克隆技术,CRISPR系统的开发利用则使基因组编辑技术取得革命性突破。基于上述原因,微生物新型防御系统的发现与研究已引起各国科学家的重视,一些新的防御系统如pAgos和DISARM等相继被发现和研究。为进一步挖掘微生物中可能蕴藏着的其他未知防御系统,最近以色列科学家Sorek等报道了从海量的微生物基因组序列中系统性发现新型防御系统的研究策略,并且通过合成生物学思路鉴定了10种新型系统的抗病毒或抗质粒功能。本文将首先介绍Sorek团队系统性发现新型防御系统的研究工作,进而总结目前已知的主要微生物新型防御系统的可能机制,并对该领域的发展态势与挑战进行分析和展望。

Microbial defense systems provide fundamental elements for biotechnology development. For example, molecular cloning techniques greatly depend on the discovery of the bacterial restriction-modification system, and similarly, deciphering the CRISPR adaptive immunity gives rise to the revolutionary genome editing technique CRISPR-Cas9. Therefore, exploring novel microbial defense systems has attracted world-wide attention, and new systems like prokaryotic Argonautes (pAgos) and the defense island system associated with restriction-modification (DISARM) were successively discovered and investigated. Recently, Sorek et al. reported a systematic strategy to predict novel defense systems within the vast microbial genomes and validated the antivirus or anti-plasmid capability of 10 candidates using synthetic biology procedures. Here, we introduce the systematic analysis pipeline developed by Sorek et al., summarize the characteristics of the novel microbial defense systems, and prospect the research trends and challenges in this rising field.