National Institutes of Health/National Cancer Institute (NIH/NCI)
R01 AI132213
米国
引用
ジャーナル: Commun Biol / 年: 2025 タイトル: Cryo-EM structures of HCV E2 glycoprotein bound to neutralizing and non-neutralizing antibodies determined using bivalent Fabs as fiducial markers. 著者: Salman Shahid / Sharanbasappa S Karade / S Saif Hasan / Rui Yin / Liqun Jiang / Yanxin Liu / Nathaniel Felbinger / Liudmila Kulakova / Eric A Toth / Zhen-Yong Keck / Steven K H Foung / Thomas ...著者: Salman Shahid / Sharanbasappa S Karade / S Saif Hasan / Rui Yin / Liqun Jiang / Yanxin Liu / Nathaniel Felbinger / Liudmila Kulakova / Eric A Toth / Zhen-Yong Keck / Steven K H Foung / Thomas R Fuerst / Brian G Pierce / Roy A Mariuzza / 要旨: Global elimination of hepatitis C virus (HCV) will require an effective cross-genotype vaccine. The HCV E2 envelope glycoprotein is the main target of neutralizing antibodies but also contains ...Global elimination of hepatitis C virus (HCV) will require an effective cross-genotype vaccine. The HCV E2 envelope glycoprotein is the main target of neutralizing antibodies but also contains epitopes that elicit non-neutralizing antibodies which may provide protection through Fc effector functions rather than direct neutralization. We determined cryo-EM structures of a broadly neutralizing antibody, a moderately neutralizing antibody, and a non-neutralizing antibody bound to E2 to resolutions of 3.8, 3.3, and 3.7 Å, respectively. Whereas the broadly neutralizing antibody targeted the front layer of E2 and the non-neutralizing antibody targeted the back layer, the moderately neutralizing antibody straddled both front and back layers, and thereby defined a new neutralizing epitope on E2. The small size of complexes between conventional (monovalent) Fabs and E2 (~110 kDa) presented a challenge for cryo-EM. Accordingly, we engineered bivalent versions of E2-specific Fabs that doubled the size of Fab-E2 complexes and conferred highly identifiable shapes to the complexes that facilitated particle selection and orientation for image processing. This study validates bivalent Fabs as new fiducial markers for cryo-EM analysis of small proteins such as HCV E2 and identifies a new target epitope for vaccine development.
解像度: 1.62→46.14 Å / Cor.coef. Fo:Fc: 0.966 / Cor.coef. Fo:Fc free: 0.951 / SU B: 2.222 / SU ML: 0.074 / 交差検証法: THROUGHOUT / ESU R: 0.093 / ESU R Free: 0.095 / 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
0.21384
5362
5 %
RANDOM
Rwork
0.17695
-
-
-
obs
0.17881
102019
98.13 %
-
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