7tcc

From Proteopedia

Cryo-EM structure of SARS-CoV-2 Omicron spike in complex with antibodies A19-46.1 and B1-182.1

Structural highlights

7tcc is a 15 chain structure with sequence from Homo sapiens and Severe acute respiratory syndrome coronavirus 2. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	Electron Microscopy, Resolution 3.86Å
Ligands:
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

SPIKE_SARS2 attaches the virion to the cell membrane by interacting with host receptor, initiating the infection (By similarity). Binding to human ACE2 receptor and internalization of the virus into the endosomes of the host cell induces conformational changes in the Spike glycoprotein (PubMed:32142651, PubMed:32075877, PubMed:32155444). Uses also human TMPRSS2 for priming in human lung cells which is an essential step for viral entry (PubMed:32142651). Proteolysis by cathepsin CTSL may unmask the fusion peptide of S2 and activate membranes fusion within endosomes.[HAMAP-Rule:MF_04099]^[1] ^[2] ^[3] mediates fusion of the virion and cellular membranes by acting as a class I viral fusion protein. Under the current model, the protein has at least three conformational states: pre-fusion native state, pre-hairpin intermediate state, and post-fusion hairpin state. During viral and target cell membrane fusion, the coiled coil regions (heptad repeats) assume a trimer-of-hairpins structure, positioning the fusion peptide in close proximity to the C-terminal region of the ectodomain. The formation of this structure appears to drive apposition and subsequent fusion of viral and target cell membranes.[HAMAP-Rule:MF_04099] Acts as a viral fusion peptide which is unmasked following S2 cleavage occurring upon virus endocytosis.[HAMAP-Rule:MF_04099]

Publication Abstract from PubMed

The rapid spread of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) B.1.1.529 (Omicron) variant and its resistance to neutralization by vaccinee and convalescent sera are driving a search for monoclonal antibodies with potent neutralization. To provide insight into effective neutralization, we determined cryo-electron microscopy structures and evaluated receptor binding domain (RBD) antibodies for their ability to bind and neutralize B.1.1.529. Mutations altered 16% of the B.1.1.529 RBD surface, clustered on an RBD ridge overlapping the angiotensin-converting enzyme 2 (ACE2)-binding surface and reduced binding of most antibodies. Substantial inhibitory activity was retained by select monoclonal antibodies-including A23-58.1, B1-182.1, COV2-2196, S2E12, A19-46.1, S309, and LY-CoV1404-that accommodated these changes and neutralized B.1.1.529. We identified combinations of antibodies with synergistic neutralization. The analysis revealed structural mechanisms for maintenance of potent neutralization against emerging variants.

Structural basis for potent antibody neutralization of SARS-CoV-2 variants including B.1.1.529.,Zhou T, Wang L, Misasi J, Pegu A, Zhang Y, Harris DR, Olia AS, Talana CA, Yang ES, Chen M, Choe M, Shi W, Teng IT, Creanga A, Jenkins C, Leung K, Liu T, Stancofski ED, Stephens T, Zhang B, Tsybovsky Y, Graham BS, Mascola JR, Sullivan NJ, Kwong PD Science. 2022 Apr 22;376(6591):eabn8897. doi: 10.1126/science.abn8897. Epub 2022 , Apr 22. PMID:35324257^[4]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Wrapp D, Wang N, Corbett KS, Goldsmith JA, Hsieh CL, Abiona O, Graham BS, McLellan JS. Cryo-EM structure of the 2019-nCoV spike in the prefusion conformation. Science. 2020 Feb 19. pii: science.abb2507. doi: 10.1126/science.abb2507. PMID:32075877 doi:http://dx.doi.org/10.1126/science.abb2507
↑ Hoffmann M, Kleine-Weber H, Schroeder S, Kruger N, Herrler T, Erichsen S, Schiergens TS, Herrler G, Wu NH, Nitsche A, Muller MA, Drosten C, Pohlmann S. SARS-CoV-2 Cell Entry Depends on ACE2 and TMPRSS2 and Is Blocked by a Clinically Proven Protease Inhibitor. Cell. 2020 Apr 16;181(2):271-280.e8. doi: 10.1016/j.cell.2020.02.052. Epub 2020, Mar 5. PMID:32142651 doi:http://dx.doi.org/10.1016/j.cell.2020.02.052
↑ Walls AC, Park YJ, Tortorici MA, Wall A, McGuire AT, Veesler D. Structure, Function, and Antigenicity of the SARS-CoV-2 Spike Glycoprotein. Cell. 2020 Mar 6. pii: S0092-8674(20)30262-2. doi: 10.1016/j.cell.2020.02.058. PMID:32155444 doi:http://dx.doi.org/10.1016/j.cell.2020.02.058
↑ Zhou T, Wang L, Misasi J, Pegu A, Zhang Y, Harris DR, Olia AS, Talana CA, Yang ES, Chen M, Choe M, Shi W, Teng IT, Creanga A, Jenkins C, Leung K, Liu T, Stancofski ED, Stephens T, Zhang B, Tsybovsky Y, Graham BS, Mascola JR, Sullivan NJ, Kwong PD. Structural basis for potent antibody neutralization of SARS-CoV-2 variants including B.1.1.529. Science. 2022 Apr 22;376(6591):eabn8897. doi: 10.1126/science.abn8897. Epub 2022 , Apr 22. PMID:35324257 doi:http://dx.doi.org/10.1126/science.abn8897