SARS-CoV-2 Spike (S) glycoprotein

Spike (S) glycoprotein corresponds to one of the leading targets for COVID-19 disease. Present on the surface of Sars-CoV-2 virus, Spike S protein is a class I fusion protein that allows the virus to enter host cells.

With a 1 273 aa length, Spike protein has 2 subunits : S1 contains the receptor-binding domain RBD and S2 induces the fusion of the viral envelop with the cellular membrane. The S1 subunit allows binding to the Angiotensin-Converting Enzyme receptor 2 (ACE2 receptor) which mediates the viral entry.

SB-PEPTIDE offers a pre-made peptide library of the original Spike protein, Omicron variant,  biotinylated versions and a pack containing variants (Delta, California…).

Spike (S) protein – peptide library reference #SB043

Spike (S) is a glycoprotein of 1 273 aa length. sb-PEPTIDE offers a library made of 316 peptides with a length of 15 amino acids and an overlap of 11 amino acids without post-translational modificaton.

Biotin-Spike (S) protein – reference #SB043-biotin

The above Sipke (S) protein library is also available with N-ter biotin.

Spike (S) Omicron protein – reference #SB133

Library made-of 315 overlapped peptides from Spike Omicron.

Biotin-Spike (S) Omicron protein – reference #SB134

Library made-of 315 overlapped biotin-peptides from Spike Omicron.

Variants package of SARS CoV-2 Spike (S) protein mutation – reference #SB072

Technical specifications

SARS CoV-2 Spike (S) protein buy Peptides length : 15 aa
SARS CoV-2 Spike (S) protein buy peptide library Offset number : 11 aa
SARS CoV-2 Spike (S) protein peptide library Amount : 0,5mg or 5*0,5mg (for each peptide)
SARS CoV-2 Spike (S) protein standard price Quality : Crude, 100% LC-MS
SARS CoV-2 Spike (S) protein standard synthesis Counter-Ion : TFA Salts (see option TFA removal)
Peptide library synthesis SARS CoV-2 Spike (S) protein Delivery format : Lyophilized or in solution, in 96-well plate or microtubes
COVID-19 peptide library buy Price : Ask for your quote
SARS CoV-2 Spike (S) protein standard solubility guidelines Peptide Solubility Guideline

 

References

Curr. Issues Mol. Biol. 28 Sep 2023;45(10):7944-7955. doi: https://doi.org/10.3390/cimb45100502

Identification of T-Cell Epitopes Using a Combined In-Silico and Experimental Approach in a Mouse Model for SARS-CoV-2

Following viral infection, T-cells are crucial for an effective immune response to intracellular pathogens, including respiratory viruses. During the COVID-19 pandemic, diverse assays were required in pre-clinical trials to evaluate the immune response following vaccination against SARS-CoV-2 and assess the response following exposure to the virus. To assess the nature and potency of the cellular response to infection or vaccination, a reliable and specific activity assay was needed. A cellular activity assay based on the presentation of short peptides (epitopes) allows the identification of T cell epitopes displayed on different alleles of the MHC, shedding light on the strength of the immune response towards antigens and aiding in antigen design for vaccination. In this report, we describe two approaches for scanning T cell epitopes on the surface glycoprotein of the SARS-CoV-2 (spike), which is utilized for attachment and entry and serves as an antigen in many vaccine candidates. We demonstrate that epitope scanning is feasible using peptide libraries or computational scanning combined with a cellular activity assay. Our scans identified four CD8 T cell epitopes, including one novel undescribed epitope. These epitopes enabled us to establish a reliable T-cell response assay, which was examined and used in various experimental mouse models for SARS-CoV-2 infection and vaccination. These approaches could potentially aid in future antigen design for vaccination and establish cellular activity assays against uncharacterized antigens of emerging pathogens.
1- Ou, X., Liu, Y., Lei, X. et al. Nat Commun 11, 1620 (2020)
Characterization of spike glycoprotein of SARS-CoV-2 on virus entry and its immune cross-reactivity with SARS-CoV

 

Background: 

Since 2002, beta coronaviruses (CoV) have caused three zoonotic outbreaks, SARS-CoV in 2002–2003, MERS-CoV in 2012, and the newly emerged SARS-CoV-2 in late 2019. However, little is currently known about the biology of SARS-CoV-2. Here, using SARS-CoV-2 S protein pseudovirus system, we confirm that human angiotensin converting enzyme 2 (hACE2) is the receptor for SARS-CoV-2, find that SARS-CoV-2 enters 293/hACE2 cells mainly through endocytosis, that PIKfyve, TPC2, and cathepsin L are critical for entry, and that SARS-CoV-2 S protein is less stable than SARS-CoV S. Polyclonal anti-SARS S1 antibodies T62 inhibit entry of SARS-CoV S but not SARS-CoV-2 S pseudovirions. Further studies using recovered SARS and COVID-19 patients’ sera show limited cross-neutralization, suggesting that recovery from one infection might not protect against the other. Our results present potential targets for development of drugs and vaccines for SARS-CoV-2.

2- Yasunori W et al. Science (2020)
Site-specific glycan analysis of the SARS-CoV-2 spike

 

SARS-CoV-2 spike protein, elaborated

Vaccine development for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is focused on the trimeric spike protein that initiates infection. Each protomer in the trimeric spike has 22 glycosylation sites. How these sites are glycosylated may affect which cells the virus can infect and could shield some epitopes from antibody neutralization. Watanabe et al. expressed and purified recombinant glycosylated spike trimers, proteolysed them to yield glycopeptides containing a single glycan, and determined the composition of the glycan sites by mass spectrometry. The analysis provides a benchmark that can be used to measure antigen quality as vaccines and antibody tests are developed.

Science this issue p. 330

Abstract

The emergence of the betacoronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), represents a considerable threat to global human health. Vaccine development is focused on the principal target of the humoral immune response, the spike (S) glycoprotein, which mediates cell entry and membrane fusion. The SARS-CoV-2 S gene encodes 22 N-linked glycan sequons per protomer, which likely play a role in protein folding and immune evasion. Here, using a site-specific mass spectrometric approach, we reveal the glycan structures on a recombinant SARS-CoV-2 S immunogen. This analysis enables mapping of the glycan-processing states across the trimeric viral spike. We show how SARS-CoV-2 S glycans differ from typical host glycan processing, which may have implications in viral pathobiology and vaccine design.

3- Alexandra C. Walls et al. Cell (2020)
Structure, Function, and Antigenicity of the SARS-CoV-2 Spike Glycoprotein

 

Background

The emergence of SARS-CoV-2 has resulted in >90,000 infections and >3,000 deaths. Coronavirus spike (S) glycoproteins promote entry into cells and are the main target of antibodies. We show that SARS-CoV-2 S uses ACE2 to enter cells and that the receptor-binding domains of SARS-CoV-2 S and SARS-CoV S bind with similar affinities to human ACE2, correlating with the efficient spread of SARS-CoV-2 among humans. We found that the SARS-CoV-2 S glycoprotein harbors a furin cleavage site at the boundary between the S1/S2 subunits, which is processed during biogenesis and sets this virus apart from SARS-CoV and SARS-related CoVs. We determined cryo-EM structures of the SARS-CoV-2 S ectodomain trimer, providing a blueprint for the design of vaccines and inhibitors of viral entry. Finally, we demonstrate that SARS-CoV S murine polyclonal antibodies potently inhibited SARS-CoV-2 S mediated entry into cells, indicating that cross-neutralizing antibodies targeting conserved S epitopes can be elicited upon vaccination.