Price/availability/specifications subject to change without notice. Unless otherwise indicated, our catalog and customized products are for research use only and not intended for human or animal diagnostic or therapeutic use.
Or leave a message with a formal purchase order (PO) Or credit card.
Recombinant SARS-CoV-2 Nucleocapsid Protein
Great for research reagent and IVD material. SARS-CoV-2 nucleocapsid antibodies, immunoassay kits, custom antibody and kit development services are available. To check more Syd Labs SARS-CoV-2 (2019-nCoV) Antigen and Antibody Reagents and Discovery Services
BP003053: Recombinant SARS-CoV-2 Nucleocapsid Protein-His-Avi (NP Protein, N Protein)
Source: recombinant SARS-CoV-2 Nucleocapsid protein (Ser2-Ala419) was expressed in mammalian cells with a His tag and Avi at the C-terminus.
Predicted molecular mass: 48.9 kDa.
Endotoxin: Less than 1 EU per ug by the LAL method.
Formulation: The recombinant SARS-CoV-2 (2019-nCoV) Nucleocapsid protein-His-Avi is supplied as 0.22 um filtered solution in 20 mM Tris, 500 mM NaCl, 10% Glycerol, pH 7.5.
Purity: > 95% by PAGE under reduced condition.
Shipping: The recombinant SARS-CoV-2 (2019-nCoV) Nucleocapsid protein-His-Avi is shipped with ice packs. 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.
The virus causing Coronavirus Disease 2019 (COVID-19) was named 2019 novel coronavirus (2019-nCoV) or severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Similar to those of other coronaviruses, there are four major structural proteins in SARS-CoV-2, S protein (spike protein), E protein (envelope protein), M protein (membrane protein), and N protein (nucleocapsid protein). The main function of Nucleocapsid protein is to protect and encapsidate the viral RNA forming viral RNP complex. It is encoded by the S segment vRNA and is abundantly expressed in the cytoplasm of infected cells.
The nucleocapsid (N) phosphoprotein is the most abundant protein in coronavirus. Because the N protein is highly immunogenic and conserved among cornnaviruses, it is often used as a marker in diagnostic immunoassays in the ELISA and colloidal gold-based rapid test kits. However, positive results may be due to past or present infection with non-SARS-CoV-2 coronavirus strains, such as coronavirus HKU1, NL63, OC43, or 229E.
To check more Syd Labs SARS-CoV-2 (2019-nCoV) Antigen and Antibody Reagents and Discovery Services
Syd Labs also provide custom antibody discovery services to screen more and better antibodies for therapeutic drugs, diagnostic immunoassays, and research reagents:
SARS-CoV-2 Nucleocapsid rabbit monoclonal antibody development service: Syd Labs immunized rabbits with SARS-CoV-2 N protein, then did single B cell sorting and culturing. There will be about 70 ul supernatant per well (clonal single B cell). If a client is interested in rabbit monoclonal antibodies against SARS-CoV-2 nucleocapsid protein (N protein), we can send you some supernatant for quick screening. Then you tell us which single B cell clone you like. We sequence the antibody VH/VL and produce a recombinant rabbit monoclonal antibody for your confirmation. You can pay for the antibody or the clone.
SARS-CoV-2 Nucleocapsid VHH nanobody development service: Syd Labs will immunize alpaca with SARS-CoV-2 Nucleocapsid protein, then do single B cell sorting and culturing or construct VHH nanobody phage display libraries. All the process is the same as "SARS-CoV-2 nucleocapsid rabbit monoclonal antibody development service". The nucleocapsid nanobodies may be used for diagnostic test kits.
To know more about our human, rabbit, and alpaca (camelid) monoclonal antibody development services, please visit:
Questions and answers:
Question: Are the nucleocapsid proteins between SARS-CoV-2 and SARS-CoV highly conserved? How about their epitope sequences?
Answer: The nucleocapsid protein from SARS-CoV shows a similarity with the SARS-CoV-2 homologue slightly above 90%. Comparison of the epitope sequences, AQFAPSASAFFGMSR, QFAPSASAFFGMSRIGM, PKGFYAEGSRGGSQASSR, YNVTQAFGRRGPEQTQGNF, and KHWPQIAQFAPSASAFF highlights that SARS-CoV scored 100% sequence identity with SARS-CoV-2 epitopes. It is the reason why the SARS-CoV nucleocapsid antibodies have been widely used in manufacturing of SARS-CoV-2 IgG/IgM antibody rapid test kits.
Question: Does it mean that there is false positive result if the nucleocapsid-based SARS-CoV-2 IgG/IgM antibody rapid test kit is used for clinical diagnostic test?
Answer: Yes, it is highly possible especially if the patient has been infected by other coronavirus(es) before.
Question: Then why are the nucleocapsid-based SARS-CoV-2 IgG/IgM antibody test kits still be widely used?
Answer: The nucleocapsid protein is the most abundant protein in SARS-CoV-2 and is highly immunogenic, it is often used as a marker in diagnostic immunoassays in the ELISA and colloidal gold-based rapid test kits. Its sensitivity is high though crossactivity is also high.
Question: Do you have discount if we place bulk order of the recombinant SARS-CoV-2 (2019-nCoV) Nucleocapsid protein-His-Avi for IVD material?
Answer: Sure. We also sell nucleocapsid monoclonal antibodies.