X-Ray Crystallographic Analysis of Spherical Plant Viruses

Research Project

Project/Area Number	61580049
Research Category	Grant-in-Aid for General Scientific Research (C)
Allocation Type	Single-year Grants
Research Field	結晶学
Research Institution	Faculty of Science, Osaka University (1987) Tottori University (1986)
Principal Investigator	FUKUYAMA Keiichi Faculty of Science, Osaka University, 理学部, 講師 (80032283)
Co-Investigator(Kenkyū-buntansha)	TSUKIHARA Tomitake Faculty of Engineering, Tottori University, 工学部, 助教授 (00032277)
Project Period (FY)	1986 – 1987
Project Status	Completed (Fiscal Year 1987)
Budget Amount *help	¥2,500,000 (Direct Cost: ¥2,500,000) Fiscal Year 1987: ¥1,000,000 (Direct Cost: ¥1,000,000) Fiscal Year 1986: ¥1,500,000 (Direct Cost: ¥1,500,000)
Keywords	Spherical Virus / Tobacco Necrosis Virus / X-Ray Analysis / 結晶構造 / タバコネクローシスウイルス / 結晶化 / X線結晶解析
Research Abstract	Tobacco necrosis virus (TNV) is a spherical plant virus consisting of 180 copies of coat protein and a single-stranded RNA. TNV was propagated in Chenopodium quinoa, and purified by differential centrifugation, gel filtration and sucrose density centrifugation. The purified TNV showed only one band at M=30,000 in SDS-polyacrylamide gel electrophoresis, and contained homogeneous particles of a diameter of approximately 28 nm in the electron microscope. TNV crystals were produced by dialyzing against 0.4 M sodium phosphate buffer with the pH adjusted to 6.0. The TNV crystals grew in the form of dodecahedron, to a maximum of 1 mm in diameter. The diffraction patterns of the crystals have shown that the crystal belongs to cubic space group p4_232 with a=338 <Ang>. The two particles in the unit cell are rotated 90 to each other about the principal axis of the crystal situated at (0,0,0) and (1/2,1/2,1/2). The nearest distance between the particles in the unit cell is 293 <Ang>. The crystals diffract X-ray to 2.5 <Ang> resolution and showed little radiation damage. Collection of three-dimensional X-ray data and preparation of heavy atom derivatives are in progress.