Recombinant SARS-CoV-2 B.1.351 L18F S GCN4-IZ Avi Protein CF

Biotinylated Recombinant SARS-CoV-2 B.1.351 L18F Spike GCN4-IZ Avi-tag His-tag (Catalog # AVI10785) binds Recombinant Human ACE-2 Fc Chimera (10544-ZN) in a functional ELISA.

2 μg/lane of Biotinylated Recombinant SARS-CoV-2 B.1.351 L18F Spike GCN4-IZ Avi-tag His-tag Protein(Catalog # AVI10785) was resolved with SDS-PAGE under reducing (R) and non-reducing (NR) conditions and visualized by Coomassie® Blue staining, showing bands at 148-168 kDa.

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

Recombinant SARS-CoV-2 B.1.351 L18F S GCN4-IZ Avi Protein CF Summary

• Additional Information: His-tag Biotinylated Beta Variant (South Africa)
• Details of Functionality: Measured by its binding ability in a functional ELISA with Recombinant Human ACE-2 Fc Chimera (Catalog # 10544-ZN). The biotin to protein ratio is greater than 0.7 as determined by the HABA assay.
• Source: Human embryonic kidney cell, HEK293-derived sars-cov-2 Spike protein
  

  SARS-CoV-2 Spike (Val16-Lys1211)(Leu18Phe, Asp80Ala, Asp215Gly, Leu242 del, Ala243 del, Leu244 del, Lys417Asn, Glu484Lys, Asn501Tyr, Asp614Gly, Ala701Val)(Arg682Ser, Arg685Ser, Lys986Pro, Val987Pro) Accession # YP_009724390.1	GCN4-IZ	Avi-tag	6-His tag
  N-terminus			C-terminus

• Accession #: YP_009724390.1
• N-terminal Sequence: Val16
• Structure / Form: Biotinylated via Avi-tag
• Protein/Peptide Type: Recombinant Proteins
• Purity: >95%, by SDS-PAGE under reducing conditions and visualized by silver stain.
• Endotoxin Note: <0.10 EU per 1 μg of the protein by the LAL method.

Applications/Dilutions

• Dilutions:
  • Bioactivity
  • Bioactivity2
• Theoretical MW: 138 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: 148-168 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 under reducing conditions and visualized by silver stain.
• 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 B.1.351 L18F S GCN4-IZ Avi Protein CF

• 2019-nCoV S Protein
• 2019-nCoV Spike
• COVID-19 Spike
• E2
• Human coronavirus spike glycoprotein
• Peplomer protein
• S glycoprotein
• S Protein
• SARS-COV-2 S protein
• SARS-COV-2 Spike glycoprotein
• SARSCOV2 Spike protein
• SARS-CoV-2
• Severe Acute Respiratory Syndrome Coronavirus 2 Spike Protein
• Spike glycoprotein
• Spike
• surface glycoprotein

Background

SARS-CoV-2, which causes the global pandemic coronavirus disease 2019 (Covid-19), belongs to a family of viruses known as coronaviruses that are commonly comprised of four structural proteins: Spike protein (S), Envelope protein (E), Membrane protein (M), and Nucleocapsid protein (N) (1). SARS-CoV-2 Spike Protein (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 the 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). The S protein of SARS-CoV-2 shares 75% and 29% amino acid (aa) sequence identity with the S protein of SARS-CoV-1 and MERS, respectively.The S Protein of the SARS-CoV-2 virus, like the SARS-CoV-1 counterpart, binds Angiotensin-Converting Enzyme 2 (ACE-2), but with much higher affinity and faster binding kinetics through the receptor binding domain (RBD) located in the C-terminal region of S1 (6). Based on structural biology studies, the RBD can be oriented either in the up/standing or down/lying state with the up/standing state associated with higher pathogenicity (7). 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 (8). It has been demonstrated that the S Protein can invade host cells through the CD147/EMMPRIN receptor and mediate membrane fusion (9, 10). A SARS-CoV-2 variant carrying amino acid substitutions N501Y, K417N, and E484K in the RBD raised the most concerns. This B.1.351 lineage, also known and 501Y.V2 variant, was first identified in the Eastern Cape province of South Africa in December 2020 and spread quickly to become the most dominant strain in the second COVID wave in South Africa (11). Two of these mutations K417N and E484K locate at the receptor binding motif (RBM) and are not found in other variants (11). The N501Y mutation is also found in London (B.1.1.7 lineage) and Brazil (P.1 lineage). The B.1.351 lineage is reported to enter cells more easily due to its enhanced affinity to ACE-2 receptor (12). It is reported to reduce the efficacy of neutralizing antibody (12, 13). Our Avi-tag Biotinylated SARS-CoV-2 B.1.351 L18F Spike (GCN4-IZ) His tagged protein features biotinylation at a single site contained within the Avi-tag, a unique 15 amino acid peptide. Protein orientation will be uniform when bound to streptavidin-coated surface due to the precise control of biotinylation and the rest of the protein is unchanged so there is no interference in the protein's bioactivity.

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. Ortega, J.T. et al. (2020) EXCLI J. 19:410.
7. Yuan, Y. et al. (2017) Nat. Commun. 8:15092.
8. Tai, W. et al. (2020) Cell. Mol. Immunol. https://doi.org/10.1016/j.it.2020.03.007.
9. Wang, X. et al. (2020) https://doi.org/10.1038/s41423-020-0424-9.
10. Wang, K. et al. (2020) bioRxiv https://doi.org/10.1101/2020.03.14.988345.
11. Tegally, H. et al. (2020) bioRxiv. Doi: https://doi.org/10.1101/2020.12.21.20248640.
12. Nelson, G. et al. (2021) bioRxiv. https://doi: 10.1101/2021.01.13.426558.
13. Wibmer, C.K. et al. (2021) bioRxiv. https://doi: 10.1101/2021.01.18.427166.

Bioinformatics

• Uniprot:
  • YP_009724390.1(Llama)