Recombinant SARS-CoV-2 B.1.621 Spike RBD His Protein, CF

R&D Systems, part of Bio-Techne | Catalog # 10897-CV

Mu Variant
R&D Systems, part of Bio-Techne
Catalog #
Availability
Size / Price
Qty
10897-CV-100
Print Quote
Bulk Order
100% Guarantee

Key Product Details

Source

HEK293

Accession #

YP_009724390.1

Conjugate

Unconjugated

Applications

Bioactivity

View all Spike RBD Proteins and Enzymes »

Product Specifications

Source

Human embryonic kidney cell, HEK293-derived sars-cov-2 Spike RBD protein
Arg319-Phe541 (Arg346Lys, Glu484Lys, Asn501Tyr), with a C-terminal 6-His tag

Purity

>95%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie® Blue Staining.

Endotoxin Level

<0.10 EU per 1 μg of the protein by the LAL method.

N-terminal Sequence Analysis

Arg319

Predicted Molecular Mass

26 kDa

SDS-PAGE

33-38 kDa, under reducing conditions.

Activity

Measured by its binding ability in a functional ELISA with Recombinant Human ACE-2 His-tag (Catalog # 933-ZN).

Scientific Data Images for Recombinant SARS-CoV-2 B.1.621 Spike RBD His Protein, CF

Recombinant SARS-CoV-2 B.1.621 Spike RBD His-tag Protein Binding Activity.

Recombinant SARS-CoV-2 B.1.621 Spike RBD His-tag (Catalog # 10897-CV) binds Recombinant Human ACE-2 His-tag (933-ZN) in a functional ELISA.

Recombinant SARS-CoV-2 B.1.621 Spike RBD His Protein SDS-PAGE.

2 μg/lane of Recombinant SARS-CoV-2 B.1.621 Spike RBD His Protein (Catalog # 10897-CV) was resolved with SDS-PAGE under reducing (R) and non-reducing (NR) conditions and visualized by Coomassie® Blue staining, showing bands at 33-38 kDa.
Surface plasmon resonance (SPR) sensorgram of Human ACE-2 binding to SARS-CoV-2 B.1.621 variant Spike RBD protein

Binding of ACE-2 to SARS-CoV-2 B.1.621 variant Spike RBD protein by surface plasmon resonance (SPR).

Recombinant SARS-CoV-2 B.1.621 variant Spike RBD protein His-tag (Catalog #10897-CV) was immobilized on a Biacore Sensor Chip CM5, and binding to recombinant human ACE-2 (933-ZN) was measured at a concentration range between 0.184 nM and 94.3 nM. The double-referenced sensorgram was fit to a 1:1 binding model to determine the binding kinetics and affinity, with an affinity constant of KD=1.92 nM.

Formulation, Preparation and Storage

10897-CV
Formulation Lyophilized from a 0.2 μm filtered solution in PBS with Trehalose.
Reconstitution Reconstitute at 500 μg/mL in PBS.
Shipping The product is shipped at ambient temperature. Upon receipt, store it immediately at the temperature recommended below.
Stability & Storage Use a manual defrost freezer and avoid repeated freeze-thaw cycles.
  • 12 months from date of receipt, -20 to -70 °C as supplied.
  • 1 month, 2 to 8 °C under sterile conditions after reconstitution.
  • 3 months, -20 to -70 °C under sterile conditions after reconstitution.

Background: Spike RBD

SARS-CoV-2, which causes the global pandemic coronavirus disease 2019 (Covid-19), belongs to a family of viruses known as coronaviruses that also include MERS-CoV and SARS-CoV-1. Coronaviruses are commonly comprised of four structural proteins: Spike protein (S), Envelope protein (E), Membrane protein (M) and Nucleocapsid protein (N) (1). The SARS-CoV-2 S protein is a glycoprotein that mediates membrane fusion and viral entry. The S protein is homotrimeric, with each ~180-kDa monomer consisting of two subunits, S1 and S2 (2). In SARS-CoV-2, as with most coronaviruses, proteolytic cleavage of the S protein into S1 and S2 subunits is required for activation. The S1 subunit is focused on attachment of the protein to the host receptor while the S2 subunit is involved with cell fusion (3-5). A receptor binding domain (RBD) in the C-terminus of the S1 subunit has been identified and the RBD of SARS-CoV-2 shares 73% amino acid (aa) identity with the RBD of the SARS-CoV-1, but only 22% aa identity with the RBD of MERS-CoV (6,7). The low aa sequence homology is consistent with the finding that SARS and MERS-CoV bind different cellular receptors (8). The RBD of SARS-CoV-2 binds a metallopeptidase, angiotensin-converting enzyme 2 (ACE-2), similar to SARS-CoV-1, but with much higher affinity and faster binding kinetics (9). Before binding to the ACE-2 receptor, structural analysis of the S1 trimer shows that only one of the three RBD domains is in the "up" conformation. This is an unstable and transient state that passes between trimeric subunits but is nevertheless an exposed state to be targeted for neutralizing antibody therapy (10). Polyclonal antibodies to the RBD of the SARS-CoV-2 protein have been shown to inhibit interaction with the ACE-2 receptor, confirming RBD as an attractive target for vaccinations or antiviral therapy (11). There is also promising work showing that the RBD may be used to detect presence of neutralizing antibodies present in a patient's bloodstream, consistent with developed immunity after exposure to the SARS-CoV-2 (12). Several emerging SARS-CoV-2 genomes have been identified with mutations in the RBD compared to the Wuhan-Hu-1 SARS-CoV-2 reference sequence. First identified in South America in early 2021, the B.1.621 variant is considered a Variant of Interest (VOI) as it contains several mutations in the RBD domain that potentially affect viral fitness and transmissibility: R346K, E484K and N501Y. Several mutations at position 346 have been associated with resistance to neutralization by monoclonal antibodies (13). Structural analysis points to E484K as a potentially crucial mutation as it creates a new site for hACE-2 binding and may enhance binding affinity (14). N501Y is thought to enhance binding affinity for hACE-2 and make the virus more easily transmissible (15, 16). Additionally, the E484K substitution alone has been shown to confer resistance to several monoclonal antibodies and is responsible for the first confirmed SARS-CoV-2 reinfection (17).

References

  1. Wu, F. et al. (2020) Nature 579:265.
  2. Tortorici, M.A. and D. Veesler (2019) Adv. Virus Res. 105:93.
  3. Bosch, B.J. et al. (2003) J. Virol. 77:8801.
  4. Belouzard, S. et al. (2009) Proc. Natl. Acad. Sci. 106:5871.
  5. Millet, J.K. and G.R. Whittaker (2015) Virus Res. 202:120.
  6. Li, W. et al. (2003) Nature 426:450.
  7. Wong, S.K. et al. (2004) J. Biol. Chem. 279:3197.
  8. Jiang, S. et al. (2020) Trends. Immunol. https://doi.org/10.1016/j.it.2020.03.007.
  9. Ortega, J.T. et al. (2020) EXCLI J. 19:410.
  10. Wrapp, D. et al. (2020) Science 367:1260.
  11. Tai, W. et al. (2020) Cell. Mol. Immunol. https://doi.org/10.1016/j.it.2020.03.007.1.
  12. Okba, N.M.A. et al. (2020). Emerg. Infect. Dis. https://doi.org/10.3201/eid2607.200841.
  13. Liu, Z. et al. (2021) Cell Host Microbe. 29:477.
  14. Wang, W.B. et al. (2021) bioRxiv https://doi.org/10.1101/2021.02.17.431566.
  15. Zahradník, J. et al. (2021) bioRxiv https://doi.org/10.1101/2021.01.06.425392.
  16. Gu, H. et al. (2020) Science. 369:1603. 
  17. Nonaka, C.K.V. et al. (2021) Emerg Infect Dis. https://doi.org/10.3201/eid2705.210191.

Long Name

Spike Receptor Binding Domain

Entrez Gene IDs

3200426 (HCoV-HKU1); 14254594 (MERS-CoV); 1489668 (SARS-CoV); 43740568 (SARS-CoV-2)

Gene Symbol

S

UniProt

YP_009724390.1

Additional Spike RBD Products

Product Documents for Recombinant SARS-CoV-2 B.1.621 Spike RBD His Protein, CF

Product Datasheets

Certificate of Analysis

To download a Certificate of Analysis, please enter a lot number in the search box below.

Note: Certificate of Analysis not available for kit components.

Product Specific Notices for Recombinant SARS-CoV-2 B.1.621 Spike RBD His Protein, CF

For research use only

Privacy and Cookie Policy
Site Map
© Copyright 2024 Bio-Techne. All Rights Reserved.