ジャーナル: PLoS Pathog / 年: 2024 タイトル: Structure and flexibility of the DNA polymerase holoenzyme of vaccinia virus. 著者: Wim P Burmeister / Laetitia Boutin / Aurelia C Balestra / Henri Gröger / Allison Ballandras-Colas / Stephanie Hutin / Christian Kraft / Clemens Grimm / Bettina Böttcher / Utz Fischer / ...著者: Wim P Burmeister / Laetitia Boutin / Aurelia C Balestra / Henri Gröger / Allison Ballandras-Colas / Stephanie Hutin / Christian Kraft / Clemens Grimm / Bettina Böttcher / Utz Fischer / Nicolas Tarbouriech / Frédéric Iseni / 要旨: The year 2022 was marked by the mpox outbreak caused by the human monkeypox virus (MPXV), which is approximately 98% identical to the vaccinia virus (VACV) at the sequence level with regard to the ...The year 2022 was marked by the mpox outbreak caused by the human monkeypox virus (MPXV), which is approximately 98% identical to the vaccinia virus (VACV) at the sequence level with regard to the proteins involved in DNA replication. We present the production in the baculovirus-insect cell system of the VACV DNA polymerase holoenzyme, which consists of the E9 polymerase in combination with its co-factor, the A20-D4 heterodimer. This led to the 3.8 Å cryo-electron microscopy (cryo-EM) structure of the DNA-free form of the holoenzyme. The model of the holoenzyme was constructed from high-resolution structures of the components of the complex and the A20 structure predicted by AlphaFold 2. The structures do not change in the context of the holoenzyme compared to the previously determined crystal and NMR structures, but the E9 thumb domain became disordered. The E9-A20-D4 structure shows the same compact arrangement with D4 folded back on E9 as observed for the recently solved MPXV holoenzyme structures in the presence and the absence of bound DNA. A conserved interface between E9 and D4 is formed by a cluster of hydrophobic residues. Small-angle X-ray scattering data show that other, more open conformations of E9-A20-D4 without the E9-D4 contact exist in solution using the flexibility of two hinge regions in A20. Biolayer interferometry (BLI) showed that the E9-D4 interaction is indeed weak and transient in the absence of DNA although it is very important, as it has not been possible to obtain viable viruses carrying mutations of key residues within the E9-D4 interface.
プロトコル: SINGLE WAVELENGTH / 単色(M)・ラウエ(L): M / 散乱光タイプ: x-ray
放射波長
波長: 0.97856 Å / 相対比: 1
反射
解像度: 1.318→40.42 Å / Num. obs: 119652 / % possible obs: 99.5 % / 冗長度: 13.29 % / CC1/2: 0.999 / Rmerge(I) obs: 0.05 / Net I/σ(I): 23.4
反射 シェル
解像度: 1.318→1.34 Å / Rmerge(I) obs: 1.134 / Num. unique obs: 5311 / CC1/2: 0.844 / % possible all: 90.2
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解析
ソフトウェア
名称
バージョン
分類
REFMAC
5.8.0258
精密化
Aimless
データスケーリング
XDS
データ削減
MOLREP
位相決定
精密化
構造決定の手法: 分子置換 / 解像度: 1.32→38.2 Å / Cor.coef. Fo:Fc: 0.982 / Cor.coef. Fo:Fc free: 0.974 / SU B: 1.52 / SU ML: 0.028 / 交差検証法: THROUGHOUT / ESU R: 0.044 / ESU R Free: 0.045 / 立体化学のターゲット値: MAXIMUM LIKELIHOOD / 詳細: HYDROGENS HAVE BEEN ADDED IN THE RIDING POSITIONS
Rfactor
反射数
%反射
Selection details
Rfree
0.16463
6094
5.1 %
RANDOM
Rwork
0.12951
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-
-
obs
0.13129
113557
99.46 %
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溶媒の処理
イオンプローブ半径: 0.8 Å / 減衰半径: 0.8 Å / VDWプローブ半径: 1.2 Å / 溶媒モデル: MASK