Several genes in Chlorella virus strain CVG-1 encode putative virion components

Area of Science:

• Virology
• Molecular Biology
• Biochemistry

Background:

• Chlorella viruses are large double-stranded DNA viruses infecting green algae.
• Phycodnaviridae family is divided into subgroups, including Pbi and NC64A.
• Understanding virus capsid proteins is crucial for viral classification and evolution.

Purpose of the Study:

• To biochemically characterize the major coat protein (Vp49) of the European Chlorella virus isolate CVG-1.
• To compare Vp49 and its gene with those from other Chlorella virus isolates.
• To investigate the genetic divergence supporting the classification of Phycodnaviridae subgroups.

Main Methods:

• Biochemical characterization of the Vp49 protein.
• N-terminal amino acid sequencing of Vp49.
• Gene isolation from CVG-1 genomic DNA using PCR.
• Sequence comparison with PBCV-1 (NC64A subgroup) and other Chlorella virus isolates.

Main Results:

• The major coat protein Vp49 of CVG-1 was identified and characterized.
• Vp49 sequences from CVG-1 and PBCV-1 show approximately 25% divergence.
• CVG-1 Vp49 is part of a gene family, with two homologous open reading frames identified.
• Major coat proteins are homologous but differ in glycosylation across strains.

Conclusions:

• The characterized Vp49 protein and its gene family support the distinct classification of Pbi and NC64A virus subgroups.
• Genetic divergence data reinforce the phylogenetic separation within the Phycodnaviridae family.