Complete Genome Sequence of Halorubrum Pleomorphic Virus 8

Abstract

Pleomorphic archaeal viruses are widespread and abundant in hypersaline environments and beyond. Still, a relatively low number of isolates are available for this viral group. Here, we present the complete genome sequence of Halorubrum pleomorphic viruses 8 (HRPV-8), which was previously isolated from the Samut Sakhon solar saltern, Thailand, on a Halorubrum species. The HRPV-8 genome was assembled into a circular 10,824-bp-long contig with a GC content of 63.2%. The genome annotation resulted in 12 open reading frames, including a VP4-like spike protein-encoding gene, which is a hallmark of pleomorphic archaeal viruses. Seven and three putative proteins in HRPV-8 were 99–100% identical to their counterparts in Halorubrum pleomorphic viruses 2 and 6 (HRPV-2 and HRPV-6), respectively, members of the genus Alphapleolipovirus. The average nucleotide identity values within these three viral genomes were 92–96%. According to VIRIDIC analyses of intergenomic similarities, HRPV-8 represents its own species. Thus, based on the observed pleolipoviral genome architecture and sequence similarities to other alphapleolipoviruses, we propose to classify HRPV-8 as a new species within the Alphapleolipovirus genus of the Pleolipoviridae family.