1C8N

TOBACCO NECROSIS VIRUS

1C8N の概要

• エントリーDOI: 10.2210/pdb1c8n/pdb
• 分子名称: COAT PROTEIN, CALCIUM ION (3 entities in total)
• 機能のキーワード: virus, icosahedral virus
• 由来する生物種: unidentified tobacco necrosis virus
• タンパク質・核酸の鎖数: 3
• 化学式量合計: 90155.95

構造登録者

Oda, Y.,Fukuyama, K. (登録日: 2000-05-20, 公開日: 2000-08-30, 最終更新日: 2023-08-09)

主引用文献

Oda, Y.,Saeki, K.,Takahashi, Y.,Maeda, T.,Naitow, H.,Tsukihara, T.,Fukuyama, K.
Crystal structure of tobacco necrosis virus at 2.25 A resolution.
J.Mol.Biol., 300:153-169, 2000

PubMed Abstract: The crystal structure of tobacco necrosis virus (TNV) has been determined by real-space averaging with 5-fold non-crystallographic symmetry, and refined to R=25.3 % for diffraction data to 2.25 A resolution. A total of 180 subunits form a T=3 virus shell with a diameter of about 280 A and a small protrusion at the 5-fold axis. In 276 amino acid residues, the respective amino terminal 86, 87 and 56 residues of the A, B and C subunits are disordered. No density for the RNA was found. The subunits have a "jelly roll" beta-barrel structure, as have the structures of the subunits of other spherical viruses. The tertiary and quaternary structures of TNV are, in particular, similar to those of southern bean mosaic virus, although they are classified in different groups. Invisible residues 1 to 56 with a high level of basic residues are considered to be located inside the particle. Sequence comparison of the coat proteins of several TNV strains showed that the sequences of the disordered segment diverge considerably as compared with those of the ordered segment, consistent with a small tertiary structural constraint being imposed on the N-terminal segment. Basic residues are localized on the subunit interfaces or inner surface of the capsid. Positive charges of the basic residues facing the interior, as well as those of the N-terminal segment, may neutralize the negative charge of the RNA inside. Five calcium ions per icosahedral asymmetric unit are located at the subunit interfaces; three are close to the exterior surface, the other two away from it. The environments of the first three are similar, and those of the other two sites are similar. These calcium ions are assumed to be responsible for the stabilization/transition of the quaternary structure of the shell. Three peptide segments ordered only in the C subunits are clustered around each 3-fold (quasi-6-fold) axis forming a beta-annulus, and may lead to quasi-equivalent interactions for the organization of the T=3 shell.

PubMed: 10864506
DOI: 10.1006/jmbi.2000.3831

実験手法

X-RAY DIFFRACTION (2.25 Å)