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Phage Phenomics: Physiological Approaches to Characterize Novel Viral Proteins
Published on: June 11, 2015
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Virophages Found in Viromes from Lake Baikal
Sergey Anatoljevich Potapov1, Olga Ivanovna Belykh1
1Limnological Institute Siberian Branch of the Russian Academy of Sciences, Ulan-Batorskaya 3, Irkutsk 664033, Russia.
Biomolecules
|December 23, 2023
Summary
Virophages, small viruses that infect giant viruses, were discovered in Lake Baikal
Area of Science:
- Environmental virology
- Microbial ecology
- Lake ecosystems
Background:
- Virophages are small dsDNA viruses that parasitize giant viruses.
- Giant viruses infect unicellular eukaryotes, playing a role in aquatic ecosystems.
- Lake Baikal's ancient and oligotrophic environment presents a unique ecosystem for microbial study.
Purpose of the Study:
- To investigate the presence and diversity of virophages in Lake Baikal.
- To characterize the genomes of identified virophages.
- To understand the ecological distribution of virophages in this ancient lake.
Main Methods:
- Analysis of eight viromes from Lake Baikal's deep and shallow waters across different seasons.
- Bioinformatic assembly of complete virophage genomes.
- Phylogenetic analysis based on conserved genes, particularly the major capsid protein (MCP).
Main Results:
- Virophage sequences were detected in all analyzed viromes, dominating over other virus groups after bacteriophages and algal viruses.
- Sixteen complete putative virophage genomes were assembled, all containing four conserved genes (MCP, mCP, PRO, ATPase).
- Virophage populations showed seasonal variation in sequence composition but no clear geographical clustering.
Conclusions:
- Virophages are a significant component of the Lake Baikal virome.
- The identified virophages possess conserved genetic features essential for their replication cycle.
- Seasonal dynamics influence virophage community structure in Lake Baikal, highlighting their ecological relevance.
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