Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: Isolation and characterization of a virus (CvV-BW1) that infects symbiotic algae of Paramecium bursaria in Lake Biwa, Japan | Hoshina et al. Virology Journal 2010 7 222 http content 7 1 222 VIROLOGY JOURNAL RESEARCH Open Access Isolation and characterization of a virus CvV-BW1 that infects symbiotic algae of Paramecium bursaria in Lake Biwa Japan 2 2 2 2 2 Ryo Hoshina 1 Mayumi Shimizu Yoichi Makino Yoshihiro Haruyama Shin-ichiro Ueda Yutaka Kato Masahiro Kasahara2 3 Bun-ichiro Ono1 2 Nobutaka Imamura2 4 Abstract Background We performed an environmental study of viruses infecting the symbiotic single-celled algae of Paramecium bursaria Paramecium bursaria Chlorella virus PBCV in Lake Biwa the largest lake in Japan. The viruses detected were all Chlorella variabilis virus CvV NC64A virus . One of them designated CvV-BW1 was subjected to further characterization. Results 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 dnapol 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. Conclusions We conclude that CvV-BW1 composes a distinct species within C. variabilis virus. Background Chlorella virus that infects Chlorella-like algae symbiotic with coelenterate Hydra viridis was first discovered in 1981 and designated HVCV Hydra viridis Chlorella virus 1 . Subsequently another Chlorella virus that infects Chlorella-like algae symbiotic with ciliate Paramecium bursaria was described Paramecium bursaria Chlorella virus PBCV 2 . Studies on HVCV and PBCV have revealed strong host-parasite relationships 3 and references therein HVCVs do not infect P. bursaria symbionts whereas PBCVs do not infect hydra symbionts PBCVs collected in the United States infect algal strain NC64A representative of . P. bursaria symbionts and other . P. .
