Diversity and comparative genomics of chimeric viruses in Sphagnum-dominated peatlands

A new group of viruses carrying naturally chimeric single-stranded (ss) DNA genomes that encompass genes derived from eukaryotic ssRNA and ssDNA viruses has been recently identified by metagenomic studies. The host range, genomic diversity, and abundance of these chimeric viruses, referred to as cruciviruses, remain largely unknown. In this article, we assembled and analyzed thirty-seven new crucivirus genomes from twelve peat viromes, representing twenty-four distinct genome organizations, and nearly tripling the number of available genomes for this group. This study provides new genome information and insights into the diversity of chimeric viruses, a necessary first step in progressing toward an accurate quantification and host range identification of these new viruses.