ジャーナル: Structure / 年: 2006 タイトル: Capsid conformational sampling in HK97 maturation visualized by X-ray crystallography and cryo-EM. 著者: Lu Gan / Jeffrey A Speir / James F Conway / Gabriel Lander / Naiqian Cheng / Brian A Firek / Roger W Hendrix / Robert L Duda / Lars Liljas / John E Johnson / 要旨: Maturation of the bacteriophage HK97 capsid from a precursor (Prohead II) to the mature state (Head II) involves a 60 A radial expansion. The mature particle is formed by 420 copies of the major ...Maturation of the bacteriophage HK97 capsid from a precursor (Prohead II) to the mature state (Head II) involves a 60 A radial expansion. The mature particle is formed by 420 copies of the major capsid protein organized on a T = 7 laevo lattice with each subunit covalently crosslinked to two neighbors. Well-characterized pH 4 expansion intermediates make HK97 valuable for investigating quaternary structural dynamics. Here, we use X-ray crystallography and cryo-EM to demonstrate that in the final transition in maturation (requiring neutral pH), pentons in Expansion Intermediate IV (EI-IV) reversibly sample 14 A translations and 6 degrees rotations relative to a fixed hexon lattice. The limit of this trajectory corresponds to the Head II conformation that is secured at this extent only by the formation of the final class of covalent crosslinks. Mutants that cannot crosslink or EI-IV particles that have been rendered incapable of forming the final crosslink remain in the EI-IV state.
#200 - 2016年8月 正二十面体型ウイルスの準対称性 (Quasisymmetry in Icosahedral Viruses) 類似性 (4)
-
集合体
登録構造単位
A: major capsid protein B: major capsid protein C: major capsid protein D: major capsid protein E: major capsid protein F: major capsid protein G: major capsid protein
A: major capsid protein B: major capsid protein C: major capsid protein D: major capsid protein E: major capsid protein F: major capsid protein G: major capsid protein
A: major capsid protein B: major capsid protein C: major capsid protein D: major capsid protein E: major capsid protein F: major capsid protein G: major capsid protein
x 5
icosahedral pentamer
1.08 MDa, 35 ポリマー
分子量 (理論値)
分子数
合計 (水以外)
1,078,161
35
ポリマ-
1,078,161
35
非ポリマー
0
0
水
0
タイプ
名称
対称操作
数
identity operation
1_555
x,y,z
1
point symmetry operation
4
4
A: major capsid protein B: major capsid protein C: major capsid protein D: major capsid protein E: major capsid protein F: major capsid protein G: major capsid protein
x 6
icosahedral 23 hexamer
1.29 MDa, 42 ポリマー
分子量 (理論値)
分子数
合計 (水以外)
1,293,793
42
ポリマ-
1,293,793
42
非ポリマー
0
0
水
0
タイプ
名称
対称操作
数
identity operation
1_555
x,y,z
1
point symmetry operation
5
5
登録構造と同一(異なる座標系)
icosahedral asymmetric unit, std point frame
タイプ
名称
対称操作
数
transform to point frame
1
6
A: major capsid protein B: major capsid protein C: major capsid protein D: major capsid protein E: major capsid protein F: major capsid protein G: major capsid protein
x 30
crystal asymmetric unit, crystal frame
6.47 MDa, 210 ポリマー
分子量 (理論値)
分子数
合計 (水以外)
6,468,967
210
ポリマ-
6,468,967
210
非ポリマー
0
0
水
0
タイプ
名称
対称操作
数
identity operation
1_555
x,y,z
2
point symmetry operation
29
単位格子
Length a, b, c (Å)
1006.394, 1006.394, 728.693
Angle α, β, γ (deg.)
90.00, 90.00, 90.00
Int Tables number
96
Space group name H-M
P43212
対称性
点対称性: (ヘルマン・モーガン記号: 532 / シェーンフリース記号: I (正20面体型対称))