Getz Landon J, Fairburn Sam R, Vivian Liu Y, Qian Amy L, Maxwell Karen L
Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada.
Nat Microbiol. 2025 Mar;10(3):724-733. doi: 10.1038/s41564-025-01927-7. Epub 2025 Jan 27.
Bacterial genomes have regions known as defence islands that encode diverse systems to protect against phage infection. Although genetic elements that capture and store gene cassettes in Vibrio species, called integrons, are known to play an important role in bacterial adaptation, a role in phage defence had not been defined. Here we combine bioinformatic and molecular techniques to show that the chromosomal integron of Vibrio parahaemolyticus is a hotspot for anti-phage defence genes. Using bioinformatics, we discovered that previously characterized defences localize to integrons. Intrigued by this discovery, we cloned 57 integron gene cassettes and identified 9 previously unrecognized systems that mediate defence. Our work reveals that integrons are an important reservoir of defence systems in V. parahaemolyticus. As integrons are of ancient origin and are widely distributed among Proteobacteria, these results provide an approach for the discovery of anti-phage defence systems across a broad range of bacteria.
细菌基因组具有被称为防御岛的区域，这些区域编码多种抵御噬菌体感染的系统。尽管在弧菌属物种中捕获和储存基因盒的遗传元件（称为整合子）在细菌适应过程中发挥重要作用，但它们在噬菌体防御中的作用尚未明确。在此，我们结合生物信息学和分子技术，证明副溶血性弧菌的染色体整合子是抗噬菌体防御基因的热点区域。通过生物信息学，我们发现先前表征的防御系统定位于整合子。受这一发现的启发，我们克隆了57个整合子基因盒，并鉴定出9个以前未被识别的介导防御的系统。我们的研究表明，整合子是副溶血性弧菌防御系统的重要储存库。由于整合子起源古老且广泛分布于变形菌门中，这些结果为发现广泛细菌中的抗噬菌体防御系统提供了一种方法。
