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Published on: October 27, 2019
Lausannevirus, a giant amoebal virus encoding histone doublets
Vincent Thomas1, Claire Bertelli, François Collyn
1Institute of Microbiology, University Hospital Center and University of Lausanne, 1011 Lausanne, Switzerland.
Environmental Microbiology
|March 12, 2011
Summary
A new large virus, Lausannevirus, infecting Acanthamoeba castellanii was discovered. Its genome analysis offers insights into the evolution of large amoeba-infecting viruses.
Area of Science:
- Virology
- Microbiology
- Evolutionary Biology
Background:
- NucleoCytoplasmic Large DNA Viruses (NCLDV) infecting algae and amoebae are of significant scientific interest.
- These viruses exhibit unique genotypic and phenotypic characteristics.
Purpose of the Study:
- To describe a newly discovered large virus, Lausannevirus, found in Acanthamoeba castellanii.
- To analyze the Lausannevirus genome and its phylogenetic relationship with other NCLDV.
Main Methods:
- Isolation and characterization of Lausannevirus from an environmental sample co-cultured with Acanthamoeba castellanii.
- Determination of the virus's host range and replication cycle.
- Genome sequencing and comparative analysis with related viruses.
Main Results:
- Lausannevirus demonstrates a limited host range, primarily infecting Acanthamoeba spp.
- The virus has an icosahedral structure (approx. 200 nm) and a rapid replication cycle (lysis in <24h).
- The 346 kb genome shares 89% of genes with Marseillevirus, placing it in the same family, and encodes histone-like proteins.
Conclusions:
- Lausannevirus represents a novel addition to the family of large amoeba-infecting viruses.
- The presence of eukaryotic/archaeal histone-like proteins in its genome provides clues about viral evolution.
- This discovery enhances our understanding of NCLDV diversity and evolution.
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