Article

A divergent clade of circular single-stranded DNA viruses from pig feces

Virus and Prion Diseases, Research Unit, National Animal Disease Center, USDA, Agricultural Research Service, PO Box 70, Ames, IA, 50010, USA, .
Archives of Virology (Impact Factor: 2.28). 04/2013; 158(10). DOI: 10.1007/s00705-013-1701-z
Source: PubMed

ABSTRACT Using metagenomics and molecular cloning methods, we characterized five novel small, circular viral genomes from pig feces that are distantly related to chimpanzee and porcine stool-associated circular viruses, (ChiSCV and PoSCV1). Phylogenetic analysis placed these viruses into a highly divergent clade of this rapidly growing new viral family. This new clade of viruses, provisionally named porcine stool-associated circular virus 2 and 3 (PoSCV2 and PoSCV3), encodes a stem-loop structure (presumably the origin of DNA replication) in the small intergenic region and a replication initiator protein commonly found in other biological systems that replicate their genomes via the rolling-circle mechanism. Furthermore, these viruses also exhibit three additional overlapping open reading frames in the large intergenic region between the capsid and replication initiator protein genes.

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