Isolation and characterization of a virus (CvV-BW1) that infects symbiotic algae of <it>Paramecium bursaria </it>in Lake Biwa, Japan

• Main Authors: Kasahara Masahiro, Kato Yutaka, Ueda Shin-ichiro, Haruyama Yoshihiro, Makino Yoichi, Shimizu Mayumi, Hoshina Ryo, Ono Bun-ichiro, Imamura Nobutaka
• Format: Article
• Language: English
• Published: BMC 2010-09-01
• Series: Virology Journal
• Online Access: http://www.virologyj.com/content/7/1/222

<p>Abstract</p> <p>Background</p> <p>We performed an environmental study of viruses infecting the symbiotic single-celled algae of <it>Paramecium bursaria </it>(<it>Paramecium bursaria Chlorella </it>virus, PBCV) in Lake Biwa, the largest lake in Japan. The viruses detected were all <it>Chlorella variabilis </it>virus (CvV = NC64A virus). One of them, designated CvV-BW1, was subjected to further characterization.</p> <p>Results</p> <p>CvV-BW1 formed small plaques and had a linear DNA genome of 370 kb, as judged by pulsed-field gel electrophoresis. Restriction analysis indicated that CvV-BW1 DNA belongs to group H, one of the most resistant groups among CvV DNAs. Based on a phylogenetic tree constructed using the <it>dnapol </it>gene, CvV was classified into two clades, A and B. CvV-BW1 belonged to clade B, in contrast to all previously identified virus strains of group H that belonged to clade A.</p> <p>Conclusions</p> <p>We conclude that CvV-BW1 composes a distinct species within <it>C. variabilis </it>virus.</p>