The Hologenome of Haliclona fulva (Porifera, Demospongiae) Reveals an Abundant and Diverse Viral Community

Viruses are among the most abundant biological entities in ocean, largely responsible of modulating nutrients fluxes and influencing microbial composition functioning. In marine invertebrate holobionts like sponges their associated microbiomes, little is known about virome composition. Here, we characterized Haliclona fulva hologenome, an encrusting low-microbial abundance sponge found across Western Mediterranean Sea (35–40 m depth) producer a large metabolic repertoire bioactive compounds harboring distinct stable microbiome. Assembled contigs from shotgun metagenome sequences obtained H. specimens were comprehensively analyzed regarding taxonomic functional content revealing its remarkable viral community dominated by single-stranded DNA (ssDNA) virus. Viral families consistently detected Circoviridae, Phycodnaviridae, Poxviridae, Herelleviridae, Mimiviridae, Microviridae, notably first reported encounter Nanoviridae Genomoviridae Porifera, expanding host range. The relative inferred bacteriophages/prophages was low, suggesting that prokaryotic this has limited range susceptibility. showed supporting general proposition specific coevolving viromes holobionts.