Recombinant SARS-CoV-2 Y453F Spike RBD His-tag Protein, CF

Recombinant SARS-CoV-2 Y453F Spike RBD His-tag (Catalog # 10744-CV) binds Recombinant Human ACE-2 His-tag (933-ZN) in a functional ELISA.

2 μg/lane of Recombinant SARS-CoV-2 Y453F Spike RBD His-tag (Catalog # 10744-CV) was resolved with SDS-PAGE under reducing (R) and non-reducing (NR) conditions and visualized by Coomassie® Blue staining, showing bands at 31-37 kDa and 28-35 kDa, respectively.

Recombinant SARS-CoV-2 Spike RBD Y453F His-tag was immobilized on a Biacore Sensor Chip CM5, and binding to recombinant human ACE-2 (933-ZN) was measured at a concentration range between 0.18 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=2.430 nM.

• Reactivity: V
• Applications: Bioactivity
• Format: Carrier-Free

Recombinant SARS-CoV-2 Y453F Spike RBD His-tag Protein, CF Summary

• Details of Functionality: Measured by its binding ability in a functional ELISA with Recombinant Human ACE-2 His-tag (Catalog # 933-ZN).
• Source: Human embryonic kidney cell, HEK293-derived sars-cov-2 Spike RBD protein
  Arg319-Phe541 (Tyr453Phe), with a C-terminal 6-His tag
• Accession #: YP_009724390.1
• N-terminal Sequence: Arg319
• Protein/Peptide Type: Recombinant Proteins
• Purity: >95%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie® Blue Staining.
• Endotoxin Note: <0.10 EU per 1 μg of the protein by the LAL method.

Applications/Dilutions

• Dilutions:
  • Bioactivity
• Theoretical MW: 26 kDa.
  Disclaimer note: The observed molecular weight of the protein may vary from the listed predicted molecular weight due to post translational modifications, post translation cleavages, relative charges, and other experimental factors.
• SDS-PAGE: 31-37 kDa, under reducing conditions

Packaging, Storage & Formulations

• 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.
• Buffer: Lyophilized from a 0.2 μm filtered solution in PBS with Trehalose.
• Purity: >95%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie® Blue Staining.
• Reconstitution Instructions: Reconstitute at 500 μg/mL in PBS.

Notes

This product is produced by and ships from R&D Systems, Inc., a Bio-Techne brand.

Alternate Names for Recombinant SARS-CoV-2 Y453F Spike RBD His-tag Protein, CF

• Spike RBD

Background

SARS-CoV-2, which caused the global pandemic coronavirus disease 2019 (Covid-19), belongs to a family of viruses known as coronaviruses that also include MERS 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 metallopeptidase, angiotensin-converting enzyme 2 (ACE-2), has been identified as a functional receptor for SARS-CoV-2 through interaction with a receptor binding domain (RBD) located at the C-terminus of S1 subunit (6,7). 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. A SARS-CoV-2 variant carrying the aa substitution Y453N in the RBD was first identified in farmed minks (8). The Spike RBD of this new virus variant was reported to show increased affinity to ACE-2, but whether the Y453N mutation in RBD would decrease the efficacy of vaccine‑induced immunity is still under investigation (9, 10).

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. Oreshkova, N. et al. (2020) Euro. Surveill. 25:2001005.
9. Bayarri-Olmos, R. et al. (2020) bioRxiv https://doi.org/10.1101/2021.01.29.428834.
10. Hayashi, T. et al. (2020) bioRxiv https://doi.org/10.1101/2020.11.27.401893.

Bioinformatics

• Uniprot:
  • YP_009724390.1(Rabbit)