Varsani Arvind, Hopkins Andrew, Lund Michael C, Krupovic Mart
The Biodesign Center for Fundamental and Applied Microbiomics, Center for Evolution and Medicine, School of Life Sciences, Arizona State University, Tempe, AZ, 85287, USA.
Structural Biology Research Unit, Department of Integrative Biomedical Sciences, University of Cape Town, Cape Town, 7925, South Africa.
Arch Virol. 2024 Dec 13;170(1):18. doi: 10.1007/s00705-024-06186-1.
The families Naryaviridae (order Rivendellvirales), Nenyaviridae (order Rohanvirales), and Vilyaviridae (order Cirlivirales), all within the class Arfiviricetes of the phylum Cressdnaviricota, include single-stranded DNA viruses associated with protozoan parasites of the genera Entamoeba and Giardia as well as viruses found in various environmental samples, also likely infecting protozoans. Here, we provide a taxonomic update for these three families, which were recently expanded with multiple new members. In particular, we established seven new genera and nine new species in the family Naryaviridae, one new genus with one new species in the family Nenyaviridae, and three new genera and nine new species in the family Vilyaviridae. We also summarize the genomic properties and protein characteristics, including conserved motifs of the rolling-circle replication initiation proteins, of the viruses in the three families. Notably, the high GC content of vilyavirids (51-61%) and considerably lower GC content of naryavirids and nenyavirids (33-44%) appear to represent an adaptation to their hosts, Giardia and Entamoeba species, respectively.
纳里亚病毒科（里文德尔病毒目）、嫩亚病毒科（罗汉病毒目）和维利亚病毒科（西尔病毒目）均属于十字形病毒门的阿尔菲病毒纲，包含与内阿米巴属和贾第虫属原生动物寄生虫相关的单链DNA病毒，以及在各种环境样本中发现的可能也感染原生动物的病毒。在此，我们对这三个科进行分类学更新，这三个科最近新增了多个成员。特别是，我们在纳里亚病毒科中建立了7个新属和9个新种，在嫩亚病毒科中建立了1个新属和1个新种，在维利亚病毒科中建立了3个新属和9个新种。我们还总结了这三个科中病毒的基因组特性和蛋白质特征，包括滚环复制起始蛋白的保守基序。值得注意的是，维利亚病毒科病毒的高GC含量（51%-61%）以及纳里亚病毒科和嫩亚病毒科病毒相对较低的GC含量（33%-44%）似乎分别代表了对其宿主贾第虫属和内阿米巴属物种的适应性。
