This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.

Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.

7f5h

From Proteopedia

(Difference between revisions)

Jump to: navigation, search

Current revision

The crystal structure of RBD-Nanobody complex, DL28 (SC4)

Structural highlights

7f5h is a 4 chain structure with sequence from Severe acute respiratory syndrome coronavirus 2 and Vicugna pacos. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	X-ray diffraction, Resolution 3Å
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

SARS-CoV-2 and its variants, such as the Omicron continue to threaten public health. The virus recognizes the host cell by attaching its Spike (S) receptor-binding domain (RBD) to the host receptor, ACE2. Therefore, RBD is a primary target for neutralizing antibodies and vaccines. Here, we report the isolation and biological and structural characterization of a single-chain antibody (nanobody) from RBD-immunized alpaca. The nanobody, named DL28, binds to RBD tightly with a K (D) of 1.56 nM and neutralizes the original SARS-CoV-2 strain with an IC(50) of 0.41 mug mL(-1). Neutralization assays with a panel of variants of concern (VOCs) reveal its wide-spectrum activity with IC(50) values ranging from 0.35 to 1.66 mug mL(-1) for the Alpha/Beta/Gamma/Delta and an IC(50) of 0.66 mug mL(-1) for the currently prevalent Omicron. Competition binding assays show that DL28 blocks ACE2-binding. However, structural characterizations and mutagenesis suggest that unlike most antibodies, the blockage by DL28 does not involve direct competition or steric hindrance. Rather, DL28 may use a "conformation competition" mechanism where it excludes ACE2 by keeping an RBD loop in a conformation incompatible with ACE2-binding.

Structural Characterization of a Neutralizing Nanobody With Broad Activity Against SARS-CoV-2 Variants.,Li T, Zhou B, Luo Z, Lai Y, Huang S, Zhou Y, Li Y, Gautam A, Bourgeau S, Wang S, Bao J, Tan J, Lavillette D, Li D Front Microbiol. 2022 Jun 2;13:875840. doi: 10.3389/fmicb.2022.875840. , eCollection 2022. PMID:35722331^[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
↑ Li T, Zhou B, Luo Z, Lai Y, Huang S, Zhou Y, Li Y, Gautam A, Bourgeau S, Wang S, Bao J, Tan J, Lavillette D, Li D. Structural Characterization of a Neutralizing Nanobody With Broad Activity Against SARS-CoV-2 Variants. Front Microbiol. 2022 Jun 2;13:875840. doi: 10.3389/fmicb.2022.875840. , eCollection 2022. PMID:35722331 doi:http://dx.doi.org/10.3389/fmicb.2022.875840

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

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/7f5h"

@@ Line 4: / Line 4: @@
 == Structural highlights ==
 <table><tr><td colspan='2'>[[7f5h]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Severe_acute_respiratory_syndrome_coronavirus_2 Severe acute respiratory syndrome coronavirus 2] and [https://en.wikipedia.org/wiki/Vicugna_pacos Vicugna pacos]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=7F5H OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=7F5H FirstGlance]. <br>
-</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=BMA:BETA-D-MANNOSE'>BMA</scene>, <scene name='pdbligand=FUC:ALPHA-L-FUCOSE'>FUC</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</scene>, <scene name='pdbligand=PO4:PHOSPHATE+ION'>PO4</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]] 3&#8491;</td></tr>
+<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=BMA:BETA-D-MANNOSE'>BMA</scene>, <scene name='pdbligand=FUC:ALPHA-L-FUCOSE'>FUC</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</scene>, <scene name='pdbligand=PO4:PHOSPHATE+ION'>PO4</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=7f5h FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7f5h OCA], [https://pdbe.org/7f5h PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=7f5h RCSB], [https://www.ebi.ac.uk/pdbsum/7f5h PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=7f5h ProSAT]</span></td></tr>
 </table>

7f5h

From Proteopedia

Current revision

The crystal structure of RBD-Nanobody complex, DL28 (SC4)

Structural highlights

Function

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

Views

Personal tools

Navigation

Search

Toolbox