Escherichia phage N4 was isolated in 1966 in Italy and has remained a genomic orphan for a long time. It encodes an extremely large virion-associated RNA polymerase unique for bacterial viruses that became characteristic for this group. In recent years, due to new and relatively inexpensive sequencing techniques the number of publicly available phage genome sequences expanded rapidly. This revealed new members of the N4-like phage group, from 33 members in 2015 to 115 N4-like viruses in 2020. Using new technologies and methods for classification, the Bacterial and Archaeal Viruses Subcommittee of the International Committee on Taxonomy of Viruses (ICTV) has moved the classification and taxonomy of bacterial viruses from mere morphological approaches to genomic and proteomic methods. The analysis of 115 N4-like genomes resulted in a huge reassessment of this group and the proposal of a new family “Schitoviridae”, including eight subfamilies and numerous new genera.

中文翻译：

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从孤儿噬菌体到拟定的新家族——N4 样病毒的多样性


埃希氏菌噬菌体 N4 于 1966 年在意大利分离出来，长期以来一直是基因组孤儿。它编码一种细菌病毒特有的极其巨大的病毒体相关RNA聚合酶，成为该群体的特征。近年来，由于新的且相对便宜的测序技术的出现，公开可用的噬菌体基因组序列的数量迅速增加。这揭示了N 4样噬菌体群的新成员，从​​2015年的33个成员增加到2020年的115个N4样病毒。利用新技术和方法进行分类，国际病毒分类委员会细菌和古菌病毒小组委员会（ ICTV）已将细菌病毒的分类和分类从单纯的形态学方法转移到基因组和蛋白质组学方法。对 115 个 N4 样基因组的分析导致了对该类群的巨大重新评估，并提出了一个新科“裂殖病毒科”，包括八个亚科和许多新属。