Department of Molecular Microbiology and Biotechnology, Institute of Biochemistry, Life Sciences Center, Vilnius University, Saulėtekio Av. 7, LT-10257 Vilnius, Lithuania.
Department of Microbiology and Biotechnology, Institute of Bioscience, Life Sciences Center, Vilnius University, Saulėtekio Av. 7, LT-10257 Vilnius, Lithuania.
Viruses. 2023 Aug 4;15(8):1691. doi: 10.3390/v15081691.
We report a detailed characterization of five thermophilic bacteriophages (phages) that were isolated from compost heaps in Vilnius, Lithuania using strains as the hosts for phage propagation. The efficiency of plating experiments revealed that phages formed plaques from 45 to 80 °C. Furthermore, most of the phages formed plaques surrounded by halo zones, indicating the presence of phage-encoded bacterial exopolysaccharide (EPS)-degrading depolymerases. Transmission Electron Microscopy (TEM) analysis revealed that all phages were siphoviruses characterized by an isometric head (from ~63 nm to ~67 nm in diameter) and a non-contractile flexible tail (from ~137 nm to ~150 nm in length). The genome sequencing resulted in genomes ranging from 38,161 to 39,016 bp. Comparative genomic and phylogenetic analysis revealed that all the isolated phages had no close relatives to date, and potentially represent three new genera within siphoviruses. The results of this study not only improve our knowledge about poorly explored thermophilic bacteriophages but also give new insights for further investigation of thermophilic and/or thermostable enzymes of bacterial viruses.
我们报告了五株嗜热噬菌体（phages）的详细特征，这些噬菌体是使用 菌株从立陶宛维尔纽斯的堆肥堆中分离出来的，用于噬菌体的繁殖。平板效率实验表明，噬菌体在 45 到 80°C 之间形成噬菌斑。此外，大多数噬菌体形成的噬菌斑周围有晕圈，表明存在噬菌体编码的细菌胞外多糖（EPS）降解解聚酶。透射电子显微镜（TEM）分析表明，所有噬菌体都是长尾噬菌体科的长尾噬菌体，其特征是等轴头部（直径约为 63nm 至 67nm）和非收缩性的柔软尾巴（长度约为 137nm 至 150nm）。基因组测序得到的基因组大小从 38161bp 到 39016bp 不等。比较基因组和系统发育分析表明，迄今为止，所有分离的噬菌体都没有密切相关的亲缘关系，并且可能代表长尾噬菌体科中的三个新属。本研究的结果不仅提高了我们对研究较少的嗜热噬菌体的认识，而且为进一步研究嗜热或耐热细菌病毒的酶提供了新的见解。
