Complete Genome Sequence of Alteromonas Virus vB_AspP-H4/4

Alteromonas virus vB_AspP-H4/4 is a member of the Podoviridae family and was isolated from North Sea water in the 1970s. The complete double-stranded DNA genome has 47,631 bp with 49 predicted genes

Bacterial and Archaeal Viruses of Himalayan Hot Springs at Manikaran Modulate Host Genomes

Hot spring-associated viruses, particularly the archaeal viruses, remain under-examined compared to bacteriophages. Previous metagenomic studies of the Manikaran hot springs in India suggested an abundance of viral DNA, which prompted us to examine the virus–host (bacterial and archaeal) interactions in sediment and microbial mat samples collected from the thermal discharges. Here, we characterize the viruses (both bacterial and archaeal) from this Himalayan hot spring using both metagenomics assembly and electron microscopy. We utilized four shotgun samples from sediment (78–98°C) and two from microbial mats (50°C) to reconstruct 65 bacteriophage genomes (24–200 kb). We also identified 59 archaeal viruses that were notably abundant across the sediment samples. Whole-genome analyses of the reconstructed bacteriophage genomes revealed greater genomic conservation in sediments (65%) compared to microbial mats (49%). However, a minimal phage genome was still maintained across both sediment and microbial mats suggesting a common origin. To complement the metagenomic data, scanning-electron and helium-ion microscopy were used to reveal diverse morphotypes of Caudovirales and archaeal viruses. The genome level annotations provide further evidence for gene-level exchange between virus and host in these hot springs, and augments our knowledgebase for bacteriophages, archaeal viruses and Clustered Regularly Interspaced Short Palindromic Repeat cassettes, which provide a critical resource for studying viromes in extreme natural environments

Complete genome sequence of Pseudoalteromonas virus vB_PspP-H6/1 that infects Pseudoalteromonas sp. strain H6

Pseudoalteromonas is a bacterial genus widely distributed in marine ecosystems. We present the genome characterization of the lytic Pseudoalteromonas virus vB_PspP-H6/1 that infects Pseudoalteromonas sp. strain H6. The virus and its host were both isolated from seawater collected from the North Sea near the island Helgoland, Germany, in the 1970s. The virus particle consists of a ~56 nm diameter icosahedral capsid and a short tail with a length of ~15 nm. The linear dsDNA genome has a size of 36,753 bp and a GC content of 45%. Genome organization was related to P22-like viruses with approximately 40% nucleotide identity to other P22-like viruses over the whole genome. These findings, together with the phylogenetic analysis, suggest Pseudoalteromonas virus vB_PspP-H6/1 is a marine P22-like virus. The study of such viruses originating from a host so far not known for P22-like viruses will extend the information about origin and evolution of P22-like viruses

Bacterial and Archaeal Viruses of Himalayan Hot Springs at Manikaran Modulate Host Genomes.

Hot spring-associated viruses, particularly the archaeal viruses, remain under-examined compared to bacteriophages. Previous metagenomic studies of the Manikaran hot springs in India suggested an abundance of viral DNA, which prompted us to examine the virus-host (bacterial and archaeal) interactions in sediment and microbial mat samples collected from the thermal discharges. Here, we characterize the viruses (both bacterial and archaeal) from this Himalayan hot spring using both metagenomics assembly and electron microscopy. We utilized four shotgun samples from sediment (78-98°C) and two from microbial mats (50°C) to reconstruct 65 bacteriophage genomes (24-200 kb). We also identified 59 archaeal viruses that were notably abundant across the sediment samples. Whole-genome analyses of the reconstructed bacteriophage genomes revealed greater genomic conservation in sediments (65%) compared to microbial mats (49%). However, a minimal phage genome was still maintained across both sediment and microbial mats suggesting a common origin. To complement the metagenomic data, scanning-electron and helium-ion microscopy were used to reveal diverse morphotypes of Caudovirales and archaeal viruses. The genome level annotations provide further evidence for gene-level exchange between virus and host in these hot springs, and augments our knowledgebase for bacteriophages, archaeal viruses and Clustered Regularly Interspaced Short Palindromic Repeat cassettes, which provide a critical resource for studying viromes in extreme natural environments

Additional file 1: Table S1. of Complete genome sequence of Pseudoalteromonas phage vB_PspS-H40/1 (formerly H40/1) that infects Pseudoalteromonas sp. strain H40 and is used as biological tracer in hydrological transport studies

Putative functions of orfs found in Pseudoalteromonas phage vB_PS-H40/1 genome. Also shown are most significant blastp hits for each orf. (DOCX 19 kb