Analysis of virus genomes from glacial environments reveals novel virus groups with unusual host interactions
Microbial communities in glacial ecosystems are diverse, active, and subjected to strong viral pressures and infection rates. In this study we analyse putative virus genomes assembled from three dsDNA viromes from cryoconite hole ecosystems of Svalbard and the Greenland Ice Sheet to assess the poten...
Published in: | Frontiers in Microbiology |
---|---|
Main Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Frontiers Media S.A.
2015
|
Subjects: | |
Online Access: | https://doi.org/10.3389/fmicb.2015.00656 https://doaj.org/article/efcaeebd85614334b29001520dfb8853 |
id |
ftdoajarticles:oai:doaj.org/article:efcaeebd85614334b29001520dfb8853 |
---|---|
record_format |
openpolar |
spelling |
ftdoajarticles:oai:doaj.org/article:efcaeebd85614334b29001520dfb8853 2023-05-15T16:30:22+02:00 Analysis of virus genomes from glacial environments reveals novel virus groups with unusual host interactions Christopher Mark Bellas Alexandre Magno Anesio Gary eBarker 2015-07-01T00:00:00Z https://doi.org/10.3389/fmicb.2015.00656 https://doaj.org/article/efcaeebd85614334b29001520dfb8853 EN eng Frontiers Media S.A. http://journal.frontiersin.org/Journal/10.3389/fmicb.2015.00656/full https://doaj.org/toc/1664-302X 1664-302X doi:10.3389/fmicb.2015.00656 https://doaj.org/article/efcaeebd85614334b29001520dfb8853 Frontiers in Microbiology, Vol 6 (2015) CRISPR cryosphere virus ecology cryoconite virus genomes lysogeny Microbiology QR1-502 article 2015 ftdoajarticles https://doi.org/10.3389/fmicb.2015.00656 2022-12-31T08:17:11Z Microbial communities in glacial ecosystems are diverse, active, and subjected to strong viral pressures and infection rates. In this study we analyse putative virus genomes assembled from three dsDNA viromes from cryoconite hole ecosystems of Svalbard and the Greenland Ice Sheet to assess the potential hosts and functional role viruses play in these habitats. We assembled 208 million reads from the virus-size fraction and developed a procedure to select genuine virus scaffolds from cellular contamination. Our curated virus library contained 546 scaffolds up to 230 Kb in length, 54 of which were circular virus consensus genomes. Analysis of virus marker genes revealed a wide range of viruses had been assembled, including bacteriophages, cyanophages, nucleocytoplasmic large DNA viruses and a virophage, with putative hosts identified as Actinobacteria, Alphaproteobacteria, Cyanobacteria, Firmicutes, Gammaproteobacteria, eukaryotic algae and amoebae. Whole genome comparisons revealed the majority of circular genome scaffolds formed 12 novel groups, two of which contained multiple phage members with plasmid-like properties, including a group of phage-plasmids possessing plasmid-like partition genes and toxin-antitoxin addiction modules to ensure their replication and a satellite phage-plasmid group. Surprisingly we also assembled a phage that not only encoded plasmid partition genes, but a clustered regularly interspaced short palindromic repeat (CRISPR)/Cas adaptive bacterial immune system. One of the spacers was an exact match for another phage in our virome, indicating that in a novel use of the system, the lysogen was potentially capable of conferring immunity on its bacterial host against other phage. Together these results suggest that highly novel and diverse groups of viruses are present in glacial environments, some of which utilise very unusual life strategies and genes to control their replication and maintain a long-term relationship with their hosts. Article in Journal/Newspaper Greenland Ice Sheet Svalbard Directory of Open Access Journals: DOAJ Articles Greenland Svalbard Frontiers in Microbiology 6 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
CRISPR cryosphere virus ecology cryoconite virus genomes lysogeny Microbiology QR1-502 |
spellingShingle |
CRISPR cryosphere virus ecology cryoconite virus genomes lysogeny Microbiology QR1-502 Christopher Mark Bellas Alexandre Magno Anesio Gary eBarker Analysis of virus genomes from glacial environments reveals novel virus groups with unusual host interactions |
topic_facet |
CRISPR cryosphere virus ecology cryoconite virus genomes lysogeny Microbiology QR1-502 |
description |
Microbial communities in glacial ecosystems are diverse, active, and subjected to strong viral pressures and infection rates. In this study we analyse putative virus genomes assembled from three dsDNA viromes from cryoconite hole ecosystems of Svalbard and the Greenland Ice Sheet to assess the potential hosts and functional role viruses play in these habitats. We assembled 208 million reads from the virus-size fraction and developed a procedure to select genuine virus scaffolds from cellular contamination. Our curated virus library contained 546 scaffolds up to 230 Kb in length, 54 of which were circular virus consensus genomes. Analysis of virus marker genes revealed a wide range of viruses had been assembled, including bacteriophages, cyanophages, nucleocytoplasmic large DNA viruses and a virophage, with putative hosts identified as Actinobacteria, Alphaproteobacteria, Cyanobacteria, Firmicutes, Gammaproteobacteria, eukaryotic algae and amoebae. Whole genome comparisons revealed the majority of circular genome scaffolds formed 12 novel groups, two of which contained multiple phage members with plasmid-like properties, including a group of phage-plasmids possessing plasmid-like partition genes and toxin-antitoxin addiction modules to ensure their replication and a satellite phage-plasmid group. Surprisingly we also assembled a phage that not only encoded plasmid partition genes, but a clustered regularly interspaced short palindromic repeat (CRISPR)/Cas adaptive bacterial immune system. One of the spacers was an exact match for another phage in our virome, indicating that in a novel use of the system, the lysogen was potentially capable of conferring immunity on its bacterial host against other phage. Together these results suggest that highly novel and diverse groups of viruses are present in glacial environments, some of which utilise very unusual life strategies and genes to control their replication and maintain a long-term relationship with their hosts. |
format |
Article in Journal/Newspaper |
author |
Christopher Mark Bellas Alexandre Magno Anesio Gary eBarker |
author_facet |
Christopher Mark Bellas Alexandre Magno Anesio Gary eBarker |
author_sort |
Christopher Mark Bellas |
title |
Analysis of virus genomes from glacial environments reveals novel virus groups with unusual host interactions |
title_short |
Analysis of virus genomes from glacial environments reveals novel virus groups with unusual host interactions |
title_full |
Analysis of virus genomes from glacial environments reveals novel virus groups with unusual host interactions |
title_fullStr |
Analysis of virus genomes from glacial environments reveals novel virus groups with unusual host interactions |
title_full_unstemmed |
Analysis of virus genomes from glacial environments reveals novel virus groups with unusual host interactions |
title_sort |
analysis of virus genomes from glacial environments reveals novel virus groups with unusual host interactions |
publisher |
Frontiers Media S.A. |
publishDate |
2015 |
url |
https://doi.org/10.3389/fmicb.2015.00656 https://doaj.org/article/efcaeebd85614334b29001520dfb8853 |
geographic |
Greenland Svalbard |
geographic_facet |
Greenland Svalbard |
genre |
Greenland Ice Sheet Svalbard |
genre_facet |
Greenland Ice Sheet Svalbard |
op_source |
Frontiers in Microbiology, Vol 6 (2015) |
op_relation |
http://journal.frontiersin.org/Journal/10.3389/fmicb.2015.00656/full https://doaj.org/toc/1664-302X 1664-302X doi:10.3389/fmicb.2015.00656 https://doaj.org/article/efcaeebd85614334b29001520dfb8853 |
op_doi |
https://doi.org/10.3389/fmicb.2015.00656 |
container_title |
Frontiers in Microbiology |
container_volume |
6 |
_version_ |
1766020086492037120 |