Figure 1

The pipeline for the identification of enriched metabolic ortholog groups and pathways within marine viral metagenomes. (A) VirMic dataset (left) is a collection of metagenomic scaffolds of the GOS project that are considered to be of viral origin and contain microbial metabolic genes. Line Islands metagenomes (right) are composed of four microbial-size fraction metagenomes and the corresponding four viral-size fraction metagenomes. (B) VirMic scaffolds were converted to the original reads to allow better estimation of gene abundance. (C) All metagenomic reads were annotated based on the KEGG Orthology database. (D) Hypergeometric enrichment analysis was performed to identify enriched KOs in the VirMic subset (left). Fisher exact test was applied in order to detect KOs enrichment in the Line Islands virome, compared to the corresponding microbiome (right). (E) Enriched KOs were mapped to KEGG metabolic pathways to detect enriched viral pathways.