Characterization and genomic analysis of the first Oceanospirillum phage, vB_OliS_GJ44, representing a novel siphoviral cluster

Abstract Background Marine bacteriophages play key roles in the community structure of microorganisms, biogeochemical cycles, and mediation genetic diversity through horizontal gene transfer. Recently, traditional isolation methods, complemented by high-throughput sequencing metagenomics technology, have greatly increased our understanding bacteriophages. Oceanospirillum, within order Oceanospirillales , are important symbiotic marine bacteria associated with hydrocarbon degradation algal blooms, especially polar regions. However, until now there has been no isolate an Oceanospirillum bacteriophage, so details their metagenome remained unknown. Results Here, we reported first phage, vB_OliS_GJ44, which was assembled into a 33,786 bp linear dsDNA genome, includes abundant tail-related recombinant proteins. The module highly adapted to host, according tetranucleotides correlations. Genomic morphological analyses identified vB_OliS_GJ44 as siphovirus, however, due distant evolutionary relationship any other known it is proposed that this virus could be classified type phage new Oceanospirivirus genus Siphoviridae family. showed synteny six uncultured phages, supports its representation environmental viral contigs from metagenomics. Homologs several genes mostly found metagenomes, suggesting prevalence oceans. Conclusions These results describe represents novel cluster exhibits interesting features related phage–host interactions evolution. Thus, propose family reconcile cluster, representative member.