SS2.06 Microbial Diversity in Time and Space
Date: Tuesday, June 11, 2002
Time: 2:15:00 PM
Location: Lecture Theatre
 
BrussaardC, Royal Netherlands Institute for Sea Research, Den Burg, Texel, Netherlands, corina.brussaard@nioz.nl
Short, S, , Univ. British Columbia, Vancouver, BC, Canada, sm.short@shaw.ca
Suttle, C, , Univ. British Columbia, Vancouver, BC, Canada, suttle@eos.ubc.ca
 
GENE SEQUENCES OF VIRUSES INFECTING PHAEOCYSTIS REVEAL THEY ARE CLOSELY RELATED TO VIRUSES THAT INFECT OTHER PRYMNESIOPHYTES
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Viruses infecting the bloom-forming phytoplankter Phaeocystis globosa were isolated from Dutch coastal waters (Southern North Sea). The viruses were either isolated during small summer blooms of P. globosa, or during a mesocosm experiment in autumn. Typically, filtered seawater samples were added to different strains of P. globosa and screened for viral lysis during 14 days. Lysed cultures were propagated every week for several months before being tested for their molecular diversity. Fragments of DNA polymerase genes were amplified from culture lysates using PCR with degenerate algal-virus-specific primers. PCR products were then cloned, sequenced, and compared to other virus DNA polymerase genes. The closest relatives to the sequences obtained in this study were sequences from the viruses CbV-PW1 and CbV-PW3 that infect the Prymnesiophyte algae Chrysochromulina spp. Therefore we conclude that the viruses isolated in this study belong to the virus genus Prymnesiovirus. These data suggest that, like their phytoplankton hosts, the Chrysochromulina and Phaeocystis viruses share a common ancestor. Therefore, we can speculate that some Prymnesioviruses and their host phytoplankton have coevolved.