PDF(Pubmed)
Abstract：
The alewife (Alosa pseudoharengus) is an anadromous herring that inhabits waters of northeastern North America. This prey species is a critical forage for piscivorous birds, mammals, and fishes in estuarine and oceanic ecosystems. During a discovery project tailored to identify potentially emerging pathogens of this species, we obtained the full genome of a novel hepadnavirus (ApHBV) from clinically normal alewives collected from the Maurice River, Great Egg Harbor River, and Delaware River in New Jersey, USA during 2015-2018. This previously undescribed hepadnavirus contained a circular DNA genome of 3146 nucleotides. Phylogenetic analysis of the polymerase protein placed this virus in the clade of metahepadnaviruses (family: Hepadnaviridae; genus: Metahepadnavirus). There was no evidence of pathology in the internal organs of infected fish and virions were not observed in liver tissues by electron microscopy. We developed a Taqman-based quantitative (qPCR) assay and screened 182 individuals collected between 2015 and 2018 and detected additional qPCR positives (n = 6). An additional complete genome was obtained in 2018 and it has 99.4% genome nucleotide identity to the first virus. Single-nucleotide polymorphisms were observed between the two genomes, including 7/9 and 12/8 synonymous vs nonsynonymous mutations across the polymerase and surface proteins, respectively. While there was no evidence that this virus was associated with disease in this species, alewives are migratory interjurisdictional fishes of management concern. Identification of microbial agents using de novo sequencing and other advanced technologies is a critical aspect of understanding disease ecology for informed population management.
摘要：
alewife（Alosapseudoharengus）是一种栖息在北美东北部水域的鲱鱼。这种猎物是食鱼鸟类的重要饲料，哺乳动物,和鱼类在河口和海洋生态系统。在一项旨在识别该物种潜在新兴病原体的发现项目中，我们从从莫里斯河收集的临床正常的妻子获得了新型嗜肝DNA病毒（ApHBV）的全基因组，伟大的鸡蛋港河，还有新泽西的特拉华河,2015-2018年美国。这种先前未描述的嗜肝DNA病毒含有3146个核苷酸的环状DNA基因组。聚合酶蛋白的系统发育分析将该病毒置于变肝DNA病毒（家族：Hepadnaviridae；属：变肝DNA病毒）的进化枝中。在感染鱼的内部器官中没有病理学的证据，并且通过电子显微镜在肝组织中未观察到病毒体。我们开发了基于Taqman的定量（qPCR）检测方法，筛选了2015年至2018年收集的182名个体，并检测到其他qPCR阳性（n=6）。2018年获得了一个额外的完整基因组，它与第一种病毒具有99.4%的基因组核苷酸同一性。在两个基因组之间观察到单核苷酸多态性,包括聚合酶和表面蛋白的7/9和12/8同义与非同义突变，分别。虽然没有证据表明这种病毒与该物种的疾病相关，妻子是管理关注的迁徙跨辖区鱼类。使用从头测序和其他先进技术鉴定微生物制剂是了解疾病生态学以进行知情人群管理的关键方面。
