Recombinant SARS-CoV-2 B.1.2 (+D399N) N (1-419) Protein, CF

2 μg/lane of Recombinant Human SARS-CoV-2 B.1.2 (+D399N) N (1-419) Protein (Catalog # 11216-CV) was resolved with SDS-PAGE under reducing (R) and non-reducing (NR) conditions and visualized by Coomassie® Blue staining, showing bands at 44-54 kDa.

• Reactivity: V
• Applications: Bioactivity
• Format: Carrier-Free

Recombinant SARS-CoV-2 B.1.2 (+D399N) N (1-419) Protein, CF Summary

• Additional Information: His-Tag
• Details of Functionality: Bioassay data are not available.
• Source: Spodoptera frugiperda, Sf 21 (baculovirus)-derived sars-cov-2 Nucleocapsid protein
  Met1-Ala419 (Pro67Ser, Pro199Leu, Asp399Asn), with a C-terminal 6-His tag
• N-terminal Sequence: Protein identity confirmed by mass spectrometry.
• Protein/Peptide Type: Recombinant Proteins
• Purity: >95%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie® Blue Staining.
• Endotoxin Note: <0.10 EU per 1 μg of the protein by the LAL method.

Applications/Dilutions

• Dilutions:
  • Bioactivity
• Theoretical MW: 46 kDa.
  Disclaimer note: The observed molecular weight of the protein may vary from the listed predicted molecular weight due to post translational modifications, post translation cleavages, relative charges, and other experimental factors.
• SDS-PAGE: 44-54 kDa, under reducing conditions.

Packaging, Storage & Formulations

• 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.
• Buffer: Lyophilized from a 0.2 μm filtered solution in PBS with Trehalose.
• Purity: >95%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie® Blue Staining.
• Reconstitution Instructions: Reconstitute at 500 μg/mL in PBS.

Notes

This product is produced by and ships from R&D Systems, Inc., a Bio-Techne brand.

Alternate Names for Recombinant SARS-CoV-2 B.1.2 (+D399N) N (1-419) Protein, CF

• N Protein
• Nucleocapsid protein
• Nucleocapsid
• ORF9a protein

Background

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). While the S, E and M proteins build up the viral envelop, the N protein is involved transcription, replication and packaging of the viral RNA genome into a helical ribonucleocapsid (RNP) (2, 3). The SARS-Cov-2 N protein is a ~45 kDa protein composed of two independent structural domains connected by a linker region. The N-terminal region contains a RNA binding domain, the linker region interacts with the M protein and the C-terminal region contains a self-association domain (2,3). The SARS-Cov-2 N protein shares 91% and 47% amino acid sequence identity with SARS-Cov-1 and MERS N protein, respectively. The SARS-Cov-2 N protein displays VSR (viral suppressor of RNA interference) activity in mammalian cells (4). As the N protein is an abundant protein during coronavirus infection and displays high immunogenic activity (5, 6), it has been used to develop diagnostic kit for detecting IgM and IgG antibodies against SARS-Cov-2 (7). Several emerging SARS-CoV-2 genomes have been identified with mutations compared to the Wuhan-Hu-1 SARS-CoV-2 reference sequence, including the B.1.2 variant. Within the N protein, there are 2 mutations, P67S and P199L, in the B.1.2 variant which might make attractive targets for the development of antiviral therapeutics or potential diagnostic tools. Additionally, the D399N mutation has been reported to affect the performance of commercial antigen tests (8).

1. Wu, F. et al. (2020) Nature 579:265.
2. Chang, C. K. et al. (2006) J. Biomed. Sci. 13:59.
3. Hurst, K.R. et al. (2009) J. Virol. 83:7221.
4. Mu, J. et al. (2020) Sci. China Life Sci. doi: 10.1007/s11427-020-1692-1.
5. Che, X. Y. et al. (2004) J. Clin. Microbiol. 42:2629.
6. Guan, M. et al. (2004) Clin. Diagn. Lab. Immunol. 11:287.
7. Liu, W. et al. (2020) J. Clin. M icrobiol. doi: 10.1128/JCM.00461-20.
8. Bourassa L. et al. (2021) J. Clin. Virol. 141:104900.

Bioinformatics

Uniprot