Recombinant SARS-CoV-2 B.1.1.529 SpikeHis-tag
Catalog Number: 11060-CV

DESCRIPTION
SourceHuman embryonic kidney cell, HEK293-derived sars-cov-2 Spike protein
SARS-CoV-2 B.1.1.529 Spike(Val16 - Lys1211)(Ala67Val, His69del, Val70del, Thr95Ile,Gly142Asp, Val143del, Tyr144del, Tyr145del,Asn211del, Leu212Ile, ins214Glu-Pro-Glu,Gly339Asp, Ser371Leu, Ser373Pro,
Ser375Phe, Lys417Asn, Asn440Lys,Gly446Ser, Ser477Asn, Thr478Lys,Glu484Ala, Gln493Arg, Gly496Ser,Gln498Arg, Asn501Tyr, Tyr505His,Thr547Lys, Asp614Gly, His655Tyr,Asn679Lys, Pro681His, Asn764Lys,
Asp796Tyr, Asn856Lys, Gln954His,Asn969Lys, Leu981Phe) (Arg682Ser,Arg685Ser, Lys986Pro, Val987Pro)
Accession # YP_009724390.1

6-His tagN-terminus

C-terminus

N-terminal Sequence Val16Analysis
Predicted MolecularMass

134 kDa

SPECIFICATIONSSDS-PAGE

146-166 kDa, under reducing conditions.

Activity

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

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

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

Formulation

Lyophilized from a 0.2 μm filtered solution in PBS with Trehalose. See Certificate of Analysis for details.

PREPARATION AND STORAGE
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.

Rev. 5/23/2024 Page 1 of 3

Recombinant SARS-CoV-2 B.1.1.529 SpikeHis-tag
Catalog Number: 11060-CV

DATA
Binding Activity

SDS-PAGE
Recombinant SARS-CoV-2
B.1.1.529 Spike His-tag Protein
Binding Activity. Recombinant
SARS-CoV-2 B.1.1.529 SpikeHis-tag (Catalog # 11060-CV)
binds Recombinant Human ACE-2
His-tag (Catalog # 933-ZN) in afunctional ELISA.

Surface Plasmon Resonance (SPR)
Recombinant SARS-CoV-2
B.1.1.529 Spike His-tag Protein
binds to Recombinant Human
ACE-2 by surface plasmon
resonance Recombinant SARSCoV-2 B.1.1.529 Spike His-tagProtein (Catalog #11060-CV) was
immobilized on a Biacore Sensor
Chip CM5, and binding torecombinant human ACE-2(Catalog # 933-ZN) wasmeasured at a concentration
range between 0.021 nM and 53.1
nM. The double-referenced
sensorgram was fit to a 1:1
binding model to determine thebinding kinetics and affinity, with
an affinity constant of Kd=3.63 nM.

Rev. 5/23/2024 Page 2 of 3

Recombinant SARS-CoV-2
B.1.1.529 Spike His-tag Protein
SDS-PAGE. 2 μg/lane of
Recombinant SARS-CoV-2
B.1.1.529 Spike His-tag Protein(Catalog # 11060-CV) was
resolved with SDS-PAGE underreducing (R) and non-reducing(NR) conditions and visualized byCoomassie® Blue staining,
showing bands at 146 - 166 kDa.

Recombinant SARS-CoV-2 B.1.1.529 SpikeHis-tag
Catalog Number: 11060-CV

BACKGROUND
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) andNucleocapsid 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 S2subunits 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% aa sequence identity with 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 a metallopeptidase, 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 subunit (6). It has been demonstrated that the S Protein can invade host cells
through the CD147/EMMPRIN receptor and mediate membrane fusion (7, 8). 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 (9). There is also promising work showing that theRBD may be used to detect presence of neutralizing antibodies present in a patient's bloodstream, consistent with developed immunity after exposure to the SARSCoV-2 (10). Several emerging SARS-CoV-2 genomes have been identified including the Omicron, or B.1.1.529, variant. First identified in November 2021 in South
Africa, the Omicron variant quickly became the predominant SARS-CoV-2 variant and is considered a variant of concern (VOC). The Omicron variant contains 32
mutations in the S protein, 3 to 4 times more than in other SARS-CoV-2 variants, that potentially affect viral fitness and transmissibility (11). Of thesemutations,15 are located in the RBD domain and allow the Omicron variant to bind ACE-2 with greater affinity and, potentially, increased transmissibility (11, 12).
Several additional mutations throughout the S protein have been shown or are predicted to enhance spike cleavage and could aid transmission (13-15). The study of
the Omicron variant's impact on immune escape and reduced neutralization activity to monoclonal antibodies along with an increased risk of reinfection, even among
vaccinated individuals, remains ongoing (16).
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. Ortega, J.T. et al. (2020) EXCLI J. 19:410.
7. Wang, K. et al. (2020) bioRxiv https://www.biorxiv.org/content/10.1101/2020.03.14.988345v1.
8. Isabel, S. et al. (2020) Sci Rep. 10, 14031. https://doi.org/10.1038/s41598-020-70827-z.
9. Tai, W. et al. (2020) Cell. Mol. Immunol. 17:613.
10. Okba, N. M. A. et al. (2020). Emerg. Infect. Dis. https://doi.org/10.3201/eid2607.200841.
11. Shah, M. and Woo, H.G. (2021) bioRxiv https://doi.org/10.1101/2021.12.04.471200.
12. Lupala, C.S. et al. (2021) bioRxiv https://doi.org/10.1101/2021.12.10.472102.
13. Zhang, L. et al. (2020) Nat Commun. 11:6013.
14. Lasek-Nesselquist, E. et al. (2021) medRxiv https://doi.org/10.1101/2021.03.10.21253285.
15. Scheepers, C. et al. (2021) medRxiv https://doi.org/10.1101/2021.08.20.21262342.
16. Callaway, E. and Ledford, H. (2021) Nature 600:197.

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