{"product_id":"biolegend-793804","title":"Biolegend, 793804, Biotinylated Recombinant SARS-CoV-2 S Protein S1 (carrier-free), 25μg","description":"\u003cp\u003eSARS-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.\u003cbr\u003e\n25μg\u003cbr\u003e\nSource: 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.\u003cbr\u003e\nMolecular 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.\u003cbr\u003e\nPurity: \u0026gt; 95%, as determined by Coomassie stained SDS-PAGE\u003cbr\u003e\nFormulation: 0.22 µm filtered protein solution is in PBS, pH 7.2\u003cbr\u003e\nEndotoxin Level: Less than 0.1 EU per µg protein as determined by the LAL method\u003cbr\u003e\nConcentration: 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.\u003cbr\u003e\nStorage \u0026amp; 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.\u003cbr\u003e\nActivity: 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.\u003cbr\u003e\nApplication: Bioassay\u003cbr\u003e\nApplication 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].\u003cbr\u003e\nProduct Citations: Bednarski E, et al. 2022. MBio. 13:e0084022. PubMed Buckner CM, et al. 2022. Cell. 185:4333. PubMed\u003cbr\u003e\nStructure: Biotinylated\u003cbr\u003e\nDistribution: SARS-CoV-2\u003cbr\u003e\nFunction: Attaches the virion to the cell membrane by interacting with host receptor, initiating the infection\u003cbr\u003e\nInteraction: Lung cells\u003cbr\u003e\nLigand\/Receptor: ACE2\u003cbr\u003e\nBioactivity: Measured by its ability to bind recombinant human ACE2\u003cbr\u003e\nBiology Area: COVID-19\u003cbr\u003e\nAntigen 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.\u003cbr\u003e\nGene ID: NA\u003cbr\u003e\nUniProt: View information about S1 on UniProt.org\u003cbr\u003e\nRegulatory Status: RUO\u003cbr\u003e\nOther Names: S1, Spike Protein\u003c\/p\u003e","brand":"Biolegend","offers":[{"title":"Default Title","offer_id":46866444255401,"sku":"793804","price":0.99,"currency_code":"USD","in_stock":true}],"url":"https:\/\/iright.com\/es\/products\/biolegend-793804","provider":"Iright","version":"1.0","type":"link"}