Hull, R. - John Innes Institute, Colney Lane, Norwich NOR 70F, England
A technique was devised for obtaining purified infectious preparations of sugar beet yellows virus (SBYV) particles. As the use of mechanical blending resulted in shearing of particles, infected leaves were hand ground in a mortar; the extracts were clarified with bentonite, concentrated using polyethylene glycol, and further purified by rate zonal and isopycnic gradient centrifugation. The purified particles had a modal length of 1270 nm, sedimented at 110 S, had an unusual ultraviolet absorption spectrum and contained about 5% RNA. The molecular weight of the infectious RNA, estimated by sedimentation and by gel electrophoresis was about 4.3 × 106; that of the coat protein subunit was about 23,500. These properties are discussed in relation to the structure of the virus particles and also are compared with the properties of viruses allied to SBYV.
Hull, R. - John Innes Institute, Colney Lane, Norwich NOR 70F, England
A technique was devised for obtaining purified infectious preparations of sugar beet yellows virus (SBYV) particles. As the use of mechanical blending resulted in shearing of particles, infected leaves were hand ground in a mortar; the extracts were clarified with bentonite, concentrated using polyethylene glycol, and further purified by rate zonal and isopycnic gradient centrifugation. The purified particles had a modal length of 1270 nm, sedimented at 110 S, had an unusual ultraviolet absorption spectrum and contained about 5% RNA. The molecular weight of the infectious RNA, estimated by sedimentation and by gel electrophoresis was about 4.3 × 106; that of the coat protein subunit was about 23,500. These properties are discussed in relation to the structure of the virus particles and also are compared with the properties of viruses allied to SBYV.