+Search query
-Structure paper
Title | Cryo-EM structure of S-Trimer, a subunit vaccine candidate for COVID-19. |
---|---|
Journal, issue, pages | J Virol, Vol. 95, Issue 11, Year 2021 |
Publish date | May 10, 2021 |
![]() | Jiahao Ma / Danmei Su / Yinyan Sun / Xueqin Huang / Ying Liang / Linqiang Fang / Yan Ma / Wenhui Li / Peng Liang / Sanduo Zheng / ![]() |
PubMed Abstract | Within a year after its emergence, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has infected over 100 million people worldwide with a death toll over 2 million. Vaccination ...Within a year after its emergence, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has infected over 100 million people worldwide with a death toll over 2 million. Vaccination remains the best hope to ultimately put this pandemic to an end. Here, using Trimer-Tag technology, we produced both wild-type (WT) and furin site mutant (MT) S-Trimers for COVID-19 vaccine studies. Cryo-EM structures of the WT and MT S-Trimers, determined at 3.2 Å and 2.6 Å respectively, revealed that both antigens adopt a tightly closed conformation and their structures are essentially identical to that of the previously solved full-length WT S protein in detergent. The tightly closed conformation is stabilized by fatty acid and polysorbate 80 binding at the receptor binding domains (RBDs) and the N terminal domains (NTDs) respectively. Additionally, we identified an important pH switch in the WT S-Trimer that shows dramatic conformational change and accounts for its increased stability at lower pH. These results validate Trimer-Tag as a platform technology in production of metastable WT S-Trimer as a candidate for COVID-19 subunit vaccine.Effective vaccine against SARS-CoV-2 is critical to end the COVID-19 pandemic. Here, using Trimer-Tag technology, we are able to produce stable and large quantities of WT S-Trimer, a subunit vaccine candidate for COVID-19 with high safety and efficacy from animal and Phase 1 clinical trial studies. Cryo-EM structures of the S-Trimer subunit vaccine candidate show that it predominately adopts tightly closed pre-fusion state, and resembles that of the native and full-length spike in detergent, confirming its structural integrity. WT S-Trimer is currently being evaluated in global Phase 2/3 clinical trial. Combining with published structures of the S protein, we also propose a model to dissect the conformation change of the spike protein before receptor binding. |
![]() | ![]() ![]() ![]() |
Methods | EM (single particle) |
Resolution | 2.6 - 3.2 Å |
Structure data | EMDB-30998, PDB-7e7b: EMDB-30999, PDB-7e7d: |
Chemicals | ![]() ChemComp-NAG: ![]() ChemComp-ELA: ![]() ChemComp-VCG: ![]() ChemComp-HOH: |
Source |
|
![]() | VIRAL PROTEIN / spike protein / COVID-19 / vaccine |