Biolegend, 793804, Biotinylated Recombinant SARS-CoV-2 S Protein S1 (carrier-free), 25μg

SARS-CoV-2 is a respiratory virus which causes coronavirus disease 2019 (COVID-19). The coronavirus spike (S) glycoprotein is a class I viral fusion protein on the outer envelope of the virion that plays a critical role in viral infection by recognizing host cell receptors and mediating fusion of the viral and cellular membranes. The S glycoprotein is synthesized as a precursor protein consisting of ~1,300 amino acids that is then cleaved into an amino (N)-terminal S1 subunit (~700 amino acids) and a carboxyl (C)-terminal S2 subunit (~600 amino acids). Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD) that can specifically bind to angiotensin-converting enzyme 2 (ACE2), the receptor on target cells. Triggered by receptor binding, proteolytic processing and/or acidic pH in the cellular compartments, the class I viral fusion protein undergoes a transition from a metastable pre-fusion state to a stable post-fusion state during infection, in which the receptor-binding subunit is cleaved, and the fusion subunit undergoes large-scale conformational rearrangements to expose the hydrophobic fusion peptide, induce the formation of a six-helix bundle, and bring the viral and cellular membranes close for fusion. The trimeric SARS coronavirus (SARS-CoV-2) S glycoprotein consisting of three S1-S2 heterodimers binds the cellular receptor angiotensin-converting enzyme 2 (ACE2) and mediates fusion of the viral and cellular membranes through a pre- to post-fusion conformation transition.
25μg
Source: SARS-CoV-2 S Protein S1, amino acid Val16-Arg685 (Accession # QHD43416.1), with a C-terminal 8-his tag and an Avi-tag was expressed in CHO cells. SARS-CoV-2 S Protein S1 was site-specifically biotinylated by enzyme BirA.
Molecular Mass: The 707 amino acid recombinant protein has a predicted molecular mass of approximately 78.9 kD. The DTT-reduced and non-reduced proteins migrate at approximately 120 kD by SDS-PAGE. The predicted N-terminal amino acid is Val.
Purity: > 95%, as determined by Coomassie stained SDS-PAGE
Formulation: 0.22 µm filtered protein solution is in PBS, pH 7.2
Endotoxin Level: Less than 0.1 EU per µg protein as determined by the LAL method
Concentration: 10 and 25 µg sizes are bottled at 200 µg/mL. 100 µg size and larger sizes are lot-specific and bottled at the concentration indicated on the vial. To obtain lot-specific concentration and expiration, please enter the lot number in our Certificate of Analysis online tool.
Storage & Handling: Unopened vial can be stored between 2°C and 8°C for up to 2 weeks, at -20°C for up to six months, or at -70°C or colder until the expiration date. For maximum results, quick spin vial prior to opening. The protein can be aliquoted and stored at -20°C or colder. Stock solutions can also be prepared at 50 - 100 µg/mL in appropriate sterile buffer, carrier protein such as 0.2 - 1% BSA or HSA can be added when preparing the stock solution. Aliquots can be stored between 2°C and 8°C for up to one week and stored at -20°C or colder for up to 3 months. Avoid repeated freeze/thaw cycles.
Activity: When recombinant ACE2-Fc Chimera (Cat. No. 793202) is immobilized at 1 μg/mL, biotinylated recombinant SARS-CoV-2 S Protein S1 binds in a dose-dependent manner. The EC50 range for this effect is 20 - 100 ng/mL. HRP Avidin (Cat. No. 405103) was used to detect the binding.
Application: Bioassay
Application Notes: BioLegend carrier-free recombinant proteins provided in liquid format are shipped on blue-ice. Our comparison testing data indicates that when handled and stored as recommended, the liquid format has equal or better stability and shelf-life compared to commercially available lyophilized proteins after reconstitution. Our liquid proteins are verified in-house to maintain activity after shipping on blue ice and are backed by our 100% satisfaction guarantee. If you have any concerns, contact us at [email protected].
Product Citations: Bednarski E, et al. 2022. MBio. 13:e0084022. PubMed Buckner CM, et al. 2022. Cell. 185:4333. PubMed
Structure: Biotinylated
Distribution: SARS-CoV-2
Function: Attaches the virion to the cell membrane by interacting with host receptor, initiating the infection
Interaction: Lung cells
Ligand/Receptor: ACE2
Bioactivity: Measured by its ability to bind recombinant human ACE2
Biology Area: COVID-19
Antigen References: Lu R, et al. 2020. Lancet. 395:565-574. Li F. 2016. Annu Rev Virol. 3:237-261. Belouzard S, et al. 2012. Viruses. 4:1011-33. Song W, et al. 2018. PLoS Pathog. 14:e1007236. Shang J, et al. 2020. Nature. 581:221-224.
Gene ID: NA
UniProt: View information about S1 on UniProt.org
Regulatory Status: RUO
Other Names: S1, Spike Protein