Product Description

Specifications

Size	100 µg, 500 µg, 1000 µg
Estimated Lead Time	1-2 business days
Species	SARS-CoV-2
Accession Number	QHD43416
Protein Name / Synonyms	Spike protein, S Protein, S1 Subunit, Host Cell Receptor Binding Domain (RBD)
Expressed Region	Arg319-Phe541
Expression System	HEK293 cells
Tag	C-terminal his-tag
Purity	>95 %
Purity Determined By	SDS-PAGE under reducing conditions and visualized by Coomassie blue staining
Molecular Weight (kDa)	Recombinant protein product has a calculated molecular mass of 25 kDa. Due to the abundant glycosylation, it migrates as approximately 30 kDa protein bands in SDS-PAGE under DTT, beta-mercaptoethanol reducing conditions. See deglycosylation analysis image below.
Format	Liquid
Formulation	Supplied as a 0.2 µm filtered solution in PBS (pH 7.4)
Concentration (lot specific)	Lot specific (see the label on the vial), determined by BCA protein assay
Research Area	Antibody Drug Development, Receptor-Ligand Binding, Infectious Disease, COVID-19
Shipping Type	Blue ice
Storage	-20°C

SDS-PAGE Image

Binding Function

Activity

Standard curve — Sandwich ELISA: this protein functions as a standard in conjunction with 130-10815 (capture antibody) and 130-10814 (detection antibody).

Storage/Stability

Upon arrival, the protein may be stored for 2 weeks at 4°C. For long term storage, it is recommended to store at -20°C or -80°C in appropriate aliquots. Avoid repeated freeze-thaw cycles.

Introduction

SARS-CoV-2, the virus responsible for COVID-19, uses its spike protein to enter host cells, with the receptor-binding domain (RBD) playing a central role in this process. The RBD within the S1 subunit specifically binds to the angiotensin-converting enzyme 2 (ACE2) receptor on human cells, facilitating viral entry and subsequent infection. This domain is a key target for neutralizing antibodies and vaccine design.

Reference: https://link.springer.com/chapter/10.1007/978-3-031-46545-1_13

Typical Data

RayBiotech's SARS-CoV-2 S1 Subunit Protein (RBD) (Cat# 230-30162) was used as the coating antigen in ELISA to measure plasma anti-RBD IgG levels. Antibody-sufficient mice showed robust responses following infection. Figure adapted from Fumagalli et al., Nature Immunology, 2024.

RayBiotech's SARS-CoV-2 S1 Subunit Protein (RBD) (Cat# 230-30162) was used to stimulate human senescent endothelial cells. As shown in the heat map, S1 treatment enhanced secretion of multiple proinflammatory SASP factors. Figure adapted from Camell et al., Science, 2021.

RayBiotech's SARS-CoV-2 S1 Subunit Protein (RBD) (Cat# 230-30162) was used as the coating antigen in ELISA to measure plasma anti-RBD IgG titers. As shown here, Nirmatrelvir-treated mice displayed reduced humoral immune responses. Figure adapted from Fumagalli et al., EMBO Molecular Medicine, 2023.

RayBiotech’s SARS-CoV-2 RBD protein (Cat# 230-30162) was used in a microscale thermophoresis assay to show that the human SLC6A20-I529V variant reduces ACE2–RBD binding affinity, revealing how host genetics may impact viral entry. Figure adapted from Nydegger et al., Viruses, 2023.

RayBiotech’s SARS-CoV-2 S1 RBD protein (Cat# 230-30162) and Nucleocapsid protein (Cat# 230-30164) were used as ELISA capture antigens to measure vaccine-induced antibody responses. Figure shows elevated RBD- and N-specific IgG titers following ZIP1642 vaccination in mice. Figure adapted from McCafferty et al., Molecular Therapy, 2022.

Custom Labeling Request

We can custom label this protein with biotin or fluorescent dyes (choose from violet, blue, green or red). Request now.

SDS-PAGE Image

Binding Function

Activity

Storage/Stability

Upon arrival, the protein may be stored for 2 weeks at 4°C. For long term storage, it is recommended to store at -20°C or -80°C in appropriate aliquots. Avoid repeated freeze-thaw cycles.