de Oliveira Pablo Sebastian Britto, Silva Júnior José Valter Joaquim, Weiblen Rudi, Flores Eduardo Furtado
Setor de Virologia, Departamento de Medicina Veterinária Preventiva, Universidade Federal de Santa Maria, Av. Roraima, 1000, Prédio 63A, Camobi, Santa Maria, Rio Grande do Sul, 97105-900, Brazil.
Programa de Pós-graduação em Medicina Veterinária, Universidade Federal de Santa Maria, Santa Maria, Rio Grande do Sul, Brazil.
Arch Virol. 2022 Dec;167(12):2545-2553. doi: 10.1007/s00705-022-05565-w. Epub 2022 Sep 14.
Bovine pestiviruses are members of the species Pestivirus A (bovine viral diarrhea virus 1, BVDV-1), Pestivirus B (BVDV-2) or Pestivirus H (HoBiPeV). To date, BVDV-2 isolates/strains have been classified into three subtypes (a-c) by phylogenetic analysis, and an additional subtype (d) has been proposed based on 5' untranslated region (UTR) secondary structures. In a previous study, we identified some BVDV-2 sequences in the GenBank database that could not be classified as subtype a, b or c by phylogenetic analysis of their genomes, UTRs or individual genes. Here, we performed a detailed study of these sequences and assessed whether they might represent a distinct BVDV-2 subtype. Initially, we collected 85 BVDV-2 complete/near-complete genomes (CNCGs) from GenBank and performed a "proof of equivalence" between phylogenetic analyses based on CNCGs and open reading frames (ORFs), which showed that ORFs may be reliably used as a reference target for BVDV-2 phylogeny, allowing us to increase our dataset to 139 sequences. Among these, we found seven sequences that could not be classified as BVDV-2a-c. The same was observed in the phylogenetic analysis of CNCGs and viral genes. In addition, the seven non-BVDV-2a-c sequences formed a distinct cluster in all phylogenetic trees, which we propose to term BVDV-2e. BVDV-2e also showed 44 amino acid changes compared to BVDV-2a-c, 20 of which are in well-defined positions. Importantly, an additional phylogenetic analysis including BVDV-2d and a pairwise comparison of BVDV-2e and BVDV-2d sequences also supported the difference between these subtypes. Finally, we propose the recognition of BVDV-2e as a distinct BVDV-2 subtype and encourage its inclusion in future phylogenetic analyses to understand its distribution and evolution.
牛瘟病毒属于瘟病毒属A种（牛病毒性腹泻病毒1型，BVDV - 1）、瘟病毒属B种（BVDV - 2）或瘟病毒属H种（HoBiPeV）。迄今为止，通过系统发育分析，BVDV - 2分离株/毒株已被分为三个亚型（a - c），并且基于5'非翻译区（UTR）二级结构提出了一个额外的亚型（d）。在先前的一项研究中，我们在GenBank数据库中鉴定出一些BVDV - 2序列，通过对其基因组、UTR或单个基因进行系统发育分析，这些序列无法被归类为a、b或c亚型。在此，我们对这些序列进行了详细研究，并评估它们是否可能代表一种独特的BVDV - 2亚型。最初，我们从GenBank收集了85个BVDV - 2完整/近乎完整的基因组（CNCG），并基于CNCG和开放阅读框（ORF）进行的系统发育分析之间进行了“等效性验证”，结果表明ORF可可靠地用作BVDV - 2系统发育的参考靶点，这使我们能够将数据集增加到139个序列。在这些序列中，我们发现有7个序列无法被归类为BVDV - 2a - c。在CNCG和病毒基因的系统发育分析中也观察到了同样的情况。此外，这7个非BVDV - 2a - c序列在所有系统发育树中形成了一个独特的簇，我们建议将其命名为BVDV - 2e。与BVDV - 2a - c相比，BVDV - 2e还显示出44个氨基酸变化，其中20个位于明确的位置。重要的是，一项包括BVDV - 2d的额外系统发育分析以及BVDV - 2e和BVDV - 2d序列的成对比较也支持了这些亚型之间的差异。最后，我们建议将BVDV - 2e识别为一种独特的BVDV - 2亚型，并鼓励在未来的系统发育分析中纳入该亚型，以了解其分布和进化情况。
