Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843-2128, United States; Center for Phage Technology, Texas A&M AgriLife Research, College Station, TX, 77843-2128, United States.
Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843-2128, United States; Center for Phage Technology, Texas A&M AgriLife Research, College Station, TX, 77843-2128, United States.
Curr Opin Microbiol. 2020 Aug;56:109-117. doi: 10.1016/j.mib.2020.09.015. Epub 2020 Oct 16.
The small lytic phages (Microviridae and Leviviridae), effect bacterial lysis with the product of a single gene. The three well-studied single-gene lysis (Sgl) proteins (E of φX174, A of Qβ, and Lys of phage M) lack direct muralytic activity, and have been shown to function as 'protein antibiotics' by acting as noncompetitive inhibitors of conserved peptidoglycan (PG) biosynthesis enzymes, MurA, MraY, and MurJ respectively. The fourth, protein L of MS2, does not inhibit PG biosynthesis but instead is hypothesized to trigger host autolytic response through an unknown mechanism. Recent advances in meta-omics approaches have led to an explosion in the available genomes of small lytic phages. Of the thousands of new genomes, only one annotated Sgl shared some sequence similarity with a known Sgl (L of MS2), highlighting the diversity in Sgls. The newly available genomic space serves as an untapped resource for discovering novel Sgls.
小型裂解噬菌体（微病毒科和Leviviridae）通过单个基因的产物来实现细菌裂解。三种研究充分的单基因裂解（Sgl）蛋白（φX174 的 E 蛋白、Qβ的 A 蛋白和噬菌体 M 的 Lys 蛋白）缺乏直接的壁裂解活性，它们被证明是作为“蛋白抗生素”发挥作用的，通过分别作为保守肽聚糖（PG）生物合成酶 MurA、MraY 和 MurJ 的非竞争性抑制剂来发挥作用。第四个蛋白 L of MS2 不抑制 PG 生物合成，而是通过未知机制引发宿主自溶反应。元组学方法的最新进展导致可供使用的小型裂解噬菌体基因组数量呈爆炸式增长。在数千个新基因组中，只有一个注释的 Sgl 与已知的 Sgl（MS2 的 L 蛋白）具有一些序列相似性，这突出了 Sgl 的多样性。新出现的基因组空间是发现新型 Sgl 的未开发资源。
