Varani Alessandro, He Susu, Siguier Patricia, Ross Karen, Chandler Michael
School of Agricultural and Veterinary Sciences, Universidade Estadual Paulista, Jaboticabal, Sao Paulo, Brazil.
State Key Laboratory of Pharmaceutical Biotechnology, Medical School of Nanjing University, Nanjing, 210093, Jiangsu, China.
Mob DNA. 2021 Mar 23;12(1):11. doi: 10.1186/s13100-021-00239-x.
The IS6 family of bacterial and archaeal insertion sequences, first identified in the early 1980s, has proved to be instrumental in the rearrangement and spread of multiple antibiotic resistance. Two IS, IS26 (found in many enterobacterial clinical isolates as components of both chromosome and plasmids) and IS257 (identified in the plasmids and chromosomes of gram-positive bacteria), have received particular attention for their clinical impact. Although few biochemical data are available concerning the transposition mechanism of these elements, genetic studies have provided some interesting observations suggesting that members of the family might transpose using an unexpected mechanism. In this review, we present an overview of the family, the distribution and phylogenetic relationships of its members, their impact on their host genomes and analyse available data concerning the particular transposition pathways they may use. We also provide a mechanistic model that explains the recent observations on one of the IS6 family transposition pathways: targeted cointegrate formation between replicons.
细菌和古细菌插入序列的IS6家族于20世纪80年代初首次被发现，已被证明在多种抗生素抗性的重排和传播中起重要作用。两种插入序列，即IS26（在许多肠杆菌临床分离株中作为染色体和质粒的组成部分被发现）和IS257（在革兰氏阳性菌的质粒和染色体中被鉴定），因其临床影响而受到特别关注。尽管关于这些元件转座机制的生化数据很少，但遗传学研究提供了一些有趣的观察结果，表明该家族成员可能使用一种意想不到的机制进行转座。在这篇综述中，我们概述了该家族、其成员的分布和系统发育关系、它们对宿主基因组的影响，并分析了有关它们可能使用的特定转座途径的现有数据。我们还提供了一个机制模型，解释了最近关于IS6家族转座途径之一的观察结果：复制子之间的靶向共整合体形成。
