Recombinant SARS-CoV-2 Spike (Active Trimer) His Protein, CF
Recombinant SARS-CoV-2 Spike (Active Trimer) His Protein, CF Summary
SARS-CoV-2 Spike Ectodomain - Trimeric Conformation
Val16-Lys1211 with a C-term His tag.
Stabilizing mutations K986P and V987P promote the prefusion conformation.
Two mutations, R682S and R685S, eliminate a Furin protease cleavage site.
For a complete list of Spike Proteins and other Coronavirus proteins
Val16-Lys1211 (Arg682Ser, Arg685Ser, Lys986Pro and Val987Pro) with a C-terminal 6-His tag
Suitable for use in serological assay development
CF stands for Carrier Free (CF). We typically add Bovine Serum Albumin (BSA) as a carrier protein to our recombinant proteins. Adding a carrier protein enhances protein stability, increases shelf-life, and allows the recombinant protein to be stored at a more dilute concentration. The carrier free version does not contain BSA.
In general, we advise purchasing the recombinant protein with BSA for use in cell or tissue culture, or as an ELISA standard. In contrast, the carrier free protein is recommended for applications, in which the presence of BSA could interfere.
|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.
2 μg/lane of Recombinant SARS-CoV-2 Spike (Active Trimer) His Protein (10549-CV) was resolved with SDS-PAGE under reducing (R) and non-reducing (NR) conditions and visualized by Coomassie® Blue staining, showing bands at 144-175 kDa.
Recombinant SARS-CoV-2 Spike (Active Trimer) His Protein (Catalog # 10549-CV) was immobilized on a Biacore Sensor Chip CM5, and binding to recombinant human ACE-2 (Catalog # 933-ZN) was measured at a concentration range between 0.37 nM and 93.5 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=1.720 nM. (Biacore T200).
SEC data shows the three-dimensional size difference between R&D Systems SARS-CoV-2 Spike Protein (Active Trimer) (10549-CV) an two competitor Spike proteins. The R&D Systems Spike protein runs at a calculated MW of 367 kDa, consistent with a true trimeric conformation. Both competitor Spike proteins run significantly larger suggesting a higher order oligomeric structure.
SDS-PAGE of 1 µg of R&D Systems Recombinant SARS-CoV-2 Spike (Active Trimer) (10549-CV) or a competitor’s Spike protein were run under reducing or non-reducing conditions and visualized by silver staining. The R&D Systems Spike protein runs as a single band compared to the competition.
In a functional flow cytometry test, (A) Recombinant SARS-CoV-2 Spike (Active Trimer) His-tag Protein (Catalog # 10549-CV) binds to HEK293 human embryonic kidney cell line transfected with recombinant human ACE-2 and EGFP. Ligand binding was detected by staining cells with APC-conjugated anti-His Monoclonal Antibody (IC050A), which does not stain the cells in the absence of recombinant protein (B).
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 (ACE2), 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 ACE2 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 the S protein aa change D614G has become the most prevalent form in the global pandemic and has been associated with greater infectivity and higher viral load (11, 12).
- Wu, F. et al. (2020) Nature 579:265.
- Tortorici, M.A. and D. Veesler (2019). Adv. Virus Res. 105:93.
- Bosch, B.J. et al. (2003). J. Virol. 77:8801.
- Belouzard, S. et al. (2009) Proc. Natl. Acad. Sci. 106:5871.
- Millet, J.K. and G.R. Whittaker (2015) Virus Res. 202:120.
- Ortega, J.T. et al. (2020) EXCLI J. 19:410.
- Yuan, Y. et al. (2017) Nat. Commun. 8:15092.
- Tai, W. et al. (2020) Cell. Mol. Immunol. https://doi.org/10.1016/j.it.2020.03.007.
- Wang, X. et al. (2020) https://doi.org/10.1038/s41423-020-0424-9.
- Wang, K. et al. (2020) bioRxiv https://www.biorxiv.org/content/10.1101/2020.03.14.988345v1.
- Korber, B. et al. (2020) Cell 182, 812.
- Zhang, L. et al. (2020) bioRxiv https://www.biorxiv.org/content/10.1101/2020.06.12.148726v1.
No product specific FAQs exist for this product, however you mayView all Proteins and Enzyme FAQs
Reviews for Recombinant SARS-CoV-2 Spike (Active Trimer) His Protein, CF
Average Rating: 5 (Based on 2 Reviews)
Have you used Recombinant SARS-CoV-2 Spike (Active Trimer) His Protein, CF?
Submit a review and receive an Amazon gift card.
$25/€18/£15/$25CAN/¥75 Yuan/¥1250 Yen for a review with an image
$10/€7/£6/$10 CAD/¥70 Yuan/¥1110 Yen for a review without an image