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Single-Stranded DNA Viruses in Antarctic Cryoconite Holes
Pacifica Sommers1, Rafaela S Fontenele2, Tayele Kringen3
1Ecology and Evolutionary Biology, University of Colorado Boulder, Boulder, CO 80309, USA. Pacifica.Sommers@Colorado.edu.
Viruses
|November 7, 2019
Summary
Researchers characterized Antarctic cryoconite hole viruses using metagenomics. They discovered diverse single-stranded DNA viruses, suggesting a unique regional virome in the McMurdo Dry Valleys.
Area of Science:
- Microbiology
- Virology
- Glaciology
Background:
- Antarctic cryoconite holes are isolated microbial habitats.
- The viral communities (viromes) within these habitats are largely unknown.
- Viruses can significantly impact microbial community dynamics.
Purpose of the Study:
- To characterize the single-stranded DNA (ssDNA) viruses present in Antarctic cryoconite holes.
- To investigate the relationship between viral diversity and microbial community structure.
- To determine the novelty and regional specificity of these Antarctic viruses.
Main Methods:
- Metagenomic sequencing of DNA extracted from cryoconite hole samples.
- Bioinformatic assembly and analysis of viral genomes.
- Comparative genomic analysis to assess viral relatedness.
Main Results:
- Seven ssDNA viral genomes were identified within the Microviridae family.
- Seven additional unclassified circular replication associated protein (Rep)-encoding single-stranded (CRESS) DNA viruses were detected.
- Eighteen other virus-like circular molecules with viral genes were identified.
- Viral genome abundance correlated with microbial diversity and abundance gradients.
- One CRESS virus showed high similarity to a previously identified Antarctic virus, while others were largely novel.
Conclusions:
- Antarctic cryoconite holes harbor a distinct and diverse ssDNA virome.
- Viral community composition appears linked to host microbial community structure.
- These findings suggest a unique regional virome adapted to the freshwater ecosystems of the McMurdo Dry Valleys.
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