Isolation and characterization of a virus infecting the freshwater algae Chrysochromulina parva

S F Mirza; M A Staniewski; C M Short; A M Long; Y V Chaban; S M Short

doi:10.1016/j.virol.2015.09.005

Isolation and characterization of a virus infecting the freshwater algae Chrysochromulina parva

Virology. 2015 Dec:486:105-15. doi: 10.1016/j.virol.2015.09.005. Epub 2015 Sep 30.

Authors

S F Mirza¹, M A Staniewski², C M Short¹, A M Long², Y V Chaban¹, S M Short³

Affiliations

¹ Department of Biology, University of Toronto Mississauga, 3359 Mississauga Road, Mississauga, Ontario, Canada L5L 1C6.
² Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, Ontario, Canada M5S 3B2.
³ Department of Biology, University of Toronto Mississauga, 3359 Mississauga Road, Mississauga, Ontario, Canada L5L 1C6; Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, Ontario, Canada M5S 3B2. Electronic address: steven.short@utoronto.ca.

PMID: 26432023
DOI: 10.1016/j.virol.2015.09.005

Abstract

Water samples from Lake Ontario, Canada were tested for lytic activity against the freshwater haptophyte algae Chrysochromulina parva. A filterable lytic agent was isolated and identified as a virus via transmission electron microscopy and molecular methods. The virus, CpV-BQ1, is icosahedral, ca. 145nm in diameter, assembled within the cytoplasm, and has a genome size of ca. 485kb. Sequences obtained through PCR-amplification of DNA polymerase (polB) genes clustered among sequences from the family Phycodnaviridae, whereas major capsid protein (MCP) sequences clustered among sequences from either the Phycodnaviridae or Mimiviridae. Based on quantitative molecular assays, C. parva׳s abundance in Lake Ontario was relatively stable, yet CpV-BQ1׳s abundance was variable suggesting complex virus-host dynamics. This study demonstrates that CpV-BQ1 is a member of the proposed order Megavirales with characteristics of both phycodnaviruses and mimiviruses indicating that, in addition to its complex ecological dynamics, it also has a complex evolutionary history.

Keywords: Algal virus; Haptophyta; Mimiviridae; NCLDV; Phycodnaviridae; Prymnesiovirus.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Canada
Capsid Proteins / genetics
Evolution, Molecular
Genome Size
Genome, Viral
Haptophyta / virology*
Lakes
Molecular Sequence Data
Phycodnaviridae / classification
Phycodnaviridae / genetics
Phycodnaviridae / isolation & purification*
Phylogeny

Substances

Capsid Proteins