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Updated: May 23, 2026
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Single Cell Micro-aspiration as an Alternative Strategy to Fluorescence-activated Cell Sorting for Giant Virus Mixture Separation
Published on: October 27, 2019
Giant viruses in the environment: their origins and evolution
1Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, Higashi-Hiroshima 739-8530, Japan.
Current Opinion in Virology
|March 24, 2012
Summary
Giant viruses challenge the definition of life with their large genomes and metabolic capabilities. Their discovery in aquatic environments suggests significant roles in ecosystem processes and evolution.
Area of Science:
- Virology
- Microbiology
- Evolutionary Biology
Background:
- Giant viruses, including Phycodnaviridae and Mimiviridae, possess large genomes.
- These genomes contain genes for metabolic processes and protein synthesis, suggesting autonomy.
- Giant viruses are often found associated with protists in aquatic ecosystems.
Purpose of the Study:
- To explore the evolutionary origins and implications of giant viruses.
- To discuss the distinction between giant viruses and living organisms.
- To highlight the ecological roles of giant viruses in natural environments.
Main Methods:
- Comparative genomics of giant virus families.
- Phylogenetic analysis to determine evolutionary relationships.
- Ecological surveys and environmental sequencing.
Main Results:
- Giant viruses share common ancestors with nucleo-cytoplasmic large DNA viruses.
- Evidence suggests giant viruses may have evolved within protist cells.
- Their association with protists indicates potential roles in biogeochemical cycling.
Conclusions:
- Giant viruses blur the lines between viruses and cellular life.
- They represent a significant area for future research in virology and evolution.
- Environmental metagenomics will likely uncover more novel giant viruses.
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