SARS-CoV-2 S1 Receptor-Binding Domain (S1-RBD), His-Tag


1 mg


SARS-CoV-2 Receptor-Binding Domain (S1-RBD), His-Tag

Recombinant spike glycoprotein Receptor-Binding Domain (RBD) from SARS-CoV-2, Wuhan-Hu-1-isolate, produced under serum-free conditions in HEK293 cells.

Predicted Molecular Mass: The SARS‐CoV‐2 Spike Protein S1 Receptor Binding Domain (S1‐RBD), His‐Tag, after glycosylation predicts a molecular mass of 26 kDa.

nCoV Amino Acids: 319-541 aa (Accession No.QHD43416.1 )

Source: Receptor-binding domain (RBD) of SARS-CoV-2 Spike protein S1 (aa 319-541) fused to the C-terminus with a 6xHis-tag.
Molecular weight: Recombinant NCOV S1 encodes the NCOV Spike glycoprotein S1 sequence. This molecule has a calculated mass of approximately 26 kDa. Recombinant S1 migrates due to glycosylation as an approximately 40-55 kDa protein under reducing conditions in SDS-PAGE.
Tag: C-terminal 6 x His-tag.
Purity: >90%, as determined by analytical CGE under reducing conditions.
Endotoxin: Endotoxin content was assayed using a LAL gel clot method. Endotoxin level was found to be less than 0.001 EU/μg.
Formulation: Liquid, 20mM NaPP, 300mM NaCl pH 7.2.
Reconstitution: A quick spin of the vial followed by reconstitution in distilled water to a concentration not less than 0.1 mg/mL. This solution can then be diluted into other buffers.
Shipping: The liquid protein is shipped on Dry Ice.
Storage: The liquid protein needs to be stored between 2°C and 8°C upon receipt.
Usage: This product is for Research Use Only. It may not be used for therapeutics or diagnostic purposes.

The spike (S) glycoprotein of coronaviruses contains protrusions that will only bind to certain receptors on the host cell. It has been reported that 2019-nCoV can infect the human Respiratory Epithelial cells through interaction with the human ACE2 receptor. The S protein is a large type I transmembrane protein containing two subunits, S1 and S2. S1 mainly contains a receptor binding domain (RBD), which is responsible for recognizing the cell surface receptor. S2 contains basic elements needed for the membrane fusion. So, S protein has a key role in the induction of neutralizing-antibody and T-cell responses, as well as protective immunity.

Known receptors binding S1 are ACE2, Angiotensin-Converting Enzyme 2; DPP4, Dipeptidyl Peptidase-4; APN, Aminopeptidase N; CEACAM, Carcinoembryonic antigen-related cell adhesion molecule 1; Sia, Sialic acid; O-ac Sia, O-acetylated Sialic acid.

The S protein is essential for both host specificity and viral infectivity. The term ‘peplomer’ is typically used to refer to a grouping of heterologous proteins on the virus surface that function together. Besides, the S protein is known to be essential in the binding of the virus to the host cell at the advent of the infection process.

The main functions for the S protein are summarized as:
Mediate receptor binding and membrane fusion; Defines the range of the hosts and specificity of the virus; Main component to bind with the neutralizing antibody; Key target for vaccine design; Can be transmitted between different hosts through gene recombination or mutation of the receptor binding domain (RBD), leading to a higher mortality rate.

SARS-CoV-2 IgG ELISA using BSV-COV-PR-48HEK as solid-phase bound capture antigen at 2μg/ml in an in-house ELISA.

5 SARS-CoV-2 positive patients tested by PCR VS 11 negative controls at 1:400 sample dilution.
Titration curve of a SARS-CoV-2 antibody-positive patient serum sample and negative control serum on solid-phase bound RBD of SARS-CoV-2 spike glycoprotein.
SARS-CoV-2 IgG ELISA using BSV-COV-PR-48HEK as solid-phase bound capture antigen at 2μg/ml, in combination with RBD-Biotin conjugate as soluble detector/tracer at 1μg/ml in an in-house ELISA.

5 SARS-CoV-2 positive patients tested by PCR VS 11 negative controls at 1:160 sample dilution.