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7x7e

From Proteopedia

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Current revision

SARS-CoV-2 RBD and Nb22

Structural highlights

7x7e is a 6 chain structure with sequence from Lama 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:	X-ray diffraction, Resolution 2.67Å
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

Current COVID-19 vaccines need to take at least one month to complete inoculation and then become effective. Around 51% of the global population is still not fully vaccinated. Instantaneous protection is an unmet need among those who are not fully vaccinated. In addition, breakthrough infections caused by SARS-CoV-2 are widely reported. All these highlight the unmet needing for short-term instantaneous prophylaxis (STIP) in the communities where SARS-CoV-2 is circulating. Previously, we reported nanobodies isolated from an alpaca immunized with the spike protein, exhibiting ultrahigh potency against SARS-CoV-2 and its variants. Herein, we found that Nb22, among our previously reported nanobodies, exhibited ultrapotent neutralization against Delta variant with an IC50 value of 0.41 ng/ml (5.13 pM). Furthermore, the crystal structural analysis revealed that the binding of Nb22 to WH01 and Delta RBDs both effectively blocked the binding of RBD to hACE2. Additionally, intranasal Nb22 exhibited protection against SARS-CoV-2 Delta variant in the post-exposure prophylaxis (PEP) and pre-exposure prophylaxis (PrEP). Of note, intranasal Nb22 also demonstrated high efficacy against SARS-CoV-2 Delta variant in STIP for seven days administered by single dose and exhibited long-lasting retention in the respiratory system for at least one month administered by four doses, providing a strategy of instantaneous short-term prophylaxis against SARS-CoV-2. Thus, ultrahigh potency, long-lasting retention in the respiratory system and stability at room-temperature make the intranasal or inhaled Nb22 to be a potential therapeutic or STIP agent against SARS-CoV-2.

Short-Term Instantaneous Prophylaxis and Efficient Treatment Against SARS-CoV-2 in hACE2 Mice Conferred by an Intranasal Nanobody (Nb22).,Wu X, Wang Y, Cheng L, Ni F, Zhu L, Ma S, Huang B, Ji M, Hu H, Li Y, Xu S, Shi H, Zhang D, Liu L, Nawaz W, Hu Q, Ye S, Liu Y, Wu Z Front Immunol. 2022 Mar 17;13:865401. doi: 10.3389/fimmu.2022.865401. eCollection, 2022. PMID:35371009^[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
↑ Wu X, Wang Y, Cheng L, Ni F, Zhu L, Ma S, Huang B, Ji M, Hu H, Li Y, Xu S, Shi H, Zhang D, Liu L, Nawaz W, Hu Q, Ye S, Liu Y, Wu Z. Short-Term Instantaneous Prophylaxis and Efficient Treatment Against SARS-CoV-2 in hACE2 Mice Conferred by an Intranasal Nanobody (Nb22). Front Immunol. 2022 Mar 17;13:865401. doi: 10.3389/fimmu.2022.865401. eCollection, 2022. PMID:35371009 doi:http://dx.doi.org/10.3389/fimmu.2022.865401

1 Structural highlights
2 Function
3 Publication Abstract from PubMed
4 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/7x7e"

Categories: Lama | Large Structures | Severe acute respiratory syndrome coronavirus 2 | Wang Y | Ye S

@@ Line 4: / Line 4: @@
 == Structural highlights ==
 <table><tr><td colspan='2'>[[7x7e]] is a 6 chain structure with sequence from [https://en.wikipedia.org/wiki/Lama Lama] and [https://en.wikipedia.org/wiki/Severe_acute_respiratory_syndrome_coronavirus_2 Severe acute respiratory syndrome coronavirus 2]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=7X7E OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=7X7E FirstGlance]. <br>
-</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=PG4:TETRAETHYLENE+GLYCOL'>PG4</scene></td></tr>
+</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.67&#8491;</td></tr>
+<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=PG4:TETRAETHYLENE+GLYCOL'>PG4</scene></td></tr>
 <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=7x7e FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7x7e OCA], [https://pdbe.org/7x7e PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=7x7e RCSB], [https://www.ebi.ac.uk/pdbsum/7x7e PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=7x7e ProSAT]</span></td></tr>
 </table>

7x7e

From Proteopedia

Current revision

SARS-CoV-2 RBD and Nb22

Structural highlights

Function

Publication Abstract from PubMed

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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