Identification of a novel neutralizing epitope on the N-terminal domain of the HCoV-229E spike protein

2021 ◽  
Author(s):  
Jiale Shi ◽  
Yuejun Shi ◽  
Ruixue Xiu ◽  
Gang Wang ◽  
Rui Liang ◽  
...  

The receptor binding domain (RBD) of the coronavirus spike protein (S) has been verified to be the main target for potent neutralizing antibodies (nAbs) in most coronaviruses, and the N-terminal domain (NTD) of some betacoronaviruses has also been indicated to induce nAbs. For alphacoronavirus HCoV-229E, its RBD has been shown to have neutralizing epitopes, and these epitopes could change over time. However, whether neutralizing epitopes exist on the NTD and whether these epitopes change like those of the RBD are still unknown. Here, we verified that neutralizing epitopes exist on the NTD of HCoV-229E. Furthermore, we characterized an NTD targeting nAb 5H10, which could neutralize both pseudotyped and authentic HCoV-229E VR740 in vitro. Epitope mapping indicated that 5H10 targeted motif E1 (147-167 aa) and identified F159 as critical for 5H10 binding. More importantly, our results revealed that motif E1 was highly conserved among clinical isolates except for F159. Further data proved that mutations at position 159 gradually appeared over time and could completely abolish the neutralizing ability of 5H10, supporting the notion that position 159 may be under selective pressure during the human epidemic. In addition, we also found that contemporary clinical serum has a stronger binding capacity for the NTD of contemporary strains than historic strains, proving that the epitope on the NTD could change over time. In summary, these findings define a novel neutralizing epitope on the NTD of HCoV-229E S and provide a theoretical basis for the design of vaccines against HCoV-229E or related coronaviruses. Importance Characterization of the neutralizing epitope of the spike (S) protein, the major invasion protein of coronaviruses, can help us better understand the evolutionary characteristics of these viruses and promote vaccine development. To date, the neutralizing epitope distribution of alphacoronaviruses is not well known. Here, we identified a neutralizing antibody that targeted the N-terminal domain (NTD) of the alphacoronavirus HCoV-229E S protein. Epitope mapping revealed a novel epitope that was not previously discovered in HCoV-229E. Further studies identified an important residue, F159. Mutations that gradually appeared over time at this site abolished the neutralizing ability of 5H10, indicating that selective pressure occurred at this position in the spread of HCoV-229E. Furthermore, we found that the epitopes within the NTD also changed over time. Taken together, our findings defined a novel neutralizing epitope and highlighted the role of the NTD in the future prevention and control of HCoV-229E or related coronaviruses.

2021 ◽  
Author(s):  
Patrick GUERIN ◽  
Nouara YAHI ◽  
Fodil AZZAZ ◽  
Henri CHAHINIAN ◽  
Jean-Marc SABATIER ◽  
...  

Abstract Infection-enhancing antibodies may limit the efficiency of Covid-19 vaccines. We analyzed the evolution ofneutralizing and facilitating epitopes in 1,860,489 SARS-CoV-2 genomes stored in the Los Alamos databasefrom June to November 2021. The structural dynamics of these epitopes was determined by molecular modelingof the spike protein on a representative panel of SARS-CoV-2 variants. D614, which belongs to an antibody-dependent-enhancement (ADE) epitope common to SARS-CoV-1 and SARS-CoV-2, has mutated to D614G in2020, which could explain why ADE has not been detected following mass vaccination. A second epitopelocated in the N-terminal domain (NTD), specific of SARS-CoV-2, is highly conserved among most variants. Incontrast, the neutralizing epitope of the NTD showed extensive variations in SARS-CoV-2 variants. The balancebetween facilitating and neutralizing antibodies is in favor of neutralization for the Wuhan strain, alpha and betavariants, but not for gamma, delta, lambda, and mu. The recently emerging omicron variant is atypic as itsmutational profiles affects both neutralization and ADE epitopes. Overall, our data reveal that the evolution ofSARS-CoV-2 has dramatically affected the ADE/neutralization balance. Future vaccines should consider thesefindings to design new formulations adapted to SARS-CoV-2 variants and lacking ADE epitopes in the spikeprotein.


2020 ◽  
Author(s):  
Zarrin Basharat ◽  
Muhammad Jahanzaib ◽  
Noor Rahman ◽  
Ishtiaq Ahmad Khan ◽  
Azra Yasmin

Abstract Recent infections caused by the novel coronavirus (SARS-CoV-2) have led to global panic and mortality. Here, we analyzed the spike (S) protein of this virus using bioinformatics tools. We aimed to determine relative changes among different coronavirus species over the past two decades and to understand the conservation of the S-protein. Representative sequences of coronaviruses were collected from humans and other animals between 2000 and 2020. Evolutionary analyses found that the S-protein did not evolve overnight, but rather continuously over time. Post-translational modification (PTM) analysis using online tools and virtual screening of S-protein against a phytochemical database of Ayurvedic medicinal compounds (n = 2103) identified the S-protein inhibitors. Among these, top ranked were Gingerol (IUPAC name: 4'-Me ether, 3,5-di-Ac 3,5-di-Gingerdiols), 1-(5-Butyltetrahydro-2-furanyl)-2-hexacosanone and Ginsenoyne N ginseng that stimulates Caspase-3, Caspase-8, and the immune system. Gingerol is found in the fresh ginger and has reputation of being a potent antiviral. These compounds might prove useful to design drugs against COVID-19.


Author(s):  
SRUTHI UNNI ◽  
Snehal Aouti ◽  
Padmanabhan Balasundaram

<p>Severe acute respiratory syndrome coronavirus (SARS-CoV-2) is an emerging new viral pathogen that causes severe respiratory disease. SARS-CoV-2 is responsible for an outbreak of COVID-19 pandemic worldwide. As there are no confirmed antiviral drugs or vaccines currently available for the treatment of COVID-19, discovering potent inhibitors or vaccines are urgently required for the benefit of humanity. The glycosylated Spike protein (S-protein) directly interacts with human angiotensin-converting enzyme 2 (ACE2) receptor through the receptor-binding domain (RBD) of S-protein. As the S-protein is exposed to the surface and is essential for entry into the host, the S-protein can be considered as a first-line therapeutic target for antiviral therapy and vaccine development. In-silico screening, docking and molecular dynamics simulation studies were performed to identify repurposing drugs using DrugBank and PubChem library against the RBD of S-protein. The study identified a laxative drug, Bisoxatin (DB09219), which is used for the treatment of constipation and preparation of the colon for surgical procedures. It binds nicely at the S-protein – ACE2 interface by making substantial pi-pi interactions with Tyr505 in the ‘Site 1’ hook region of RBD and hydrophilic interactions with Glu406, Ser494 and Thr500. Bisoxatin consistently binds to the protein throughout the 100 ns simulation. Taken together, we propose that the discovered molecule, Bisoxatin may be a potent repurpose drug to develop new chemical libraries for inhibiting SARS-CoV-2 entry into the host.</p>


2020 ◽  
Author(s):  
SRUTHI UNNI ◽  
Snehal Aouti ◽  
Padmanabhan Balasundaram

<p>Severe acute respiratory syndrome coronavirus (SARS-CoV-2) is an emerging new viral pathogen that causes severe respiratory disease. SARS-CoV-2 is responsible for an outbreak of COVID-19 pandemic worldwide. As there are no confirmed antiviral drugs or vaccines currently available for the treatment of COVID-19, discovering potent inhibitors or vaccines are urgently required for the benefit of humanity. The glycosylated Spike protein (S-protein) directly interacts with human angiotensin-converting enzyme 2 (ACE2) receptor through the receptor-binding domain (RBD) of S-protein. As the S-protein is exposed to the surface and is essential for entry into the host, the S-protein can be considered as a first-line therapeutic target for antiviral therapy and vaccine development. In-silico screening, docking and molecular dynamics simulation studies were performed to identify repurposing drugs using DrugBank and PubChem library against the RBD of S-protein. The study identified a laxative drug, Bisoxatin (DB09219), which is used for the treatment of constipation and preparation of the colon for surgical procedures. It binds nicely at the S-protein – ACE2 interface by making substantial pi-pi interactions with Tyr505 in the ‘Site 1’ hook region of RBD and hydrophilic interactions with Glu406, Ser494 and Thr500. Bisoxatin consistently binds to the protein throughout the 100 ns simulation. Taken together, we propose that the discovered molecule, Bisoxatin may be a potent repurpose drug to develop new chemical libraries for inhibiting SARS-CoV-2 entry into the host.</p>


2021 ◽  
Vol 12 ◽  
Author(s):  
Ranjith Kumavath ◽  
Debmalya Barh ◽  
Bruno Silva Andrade ◽  
Madangchanok Imchen ◽  
Flavia Figueira Aburjaile ◽  
...  

The Spike (S) protein of the SARS-CoV-2 virus is critical for its ability to attach and fuse into the host cells, leading to infection, and transmission. In this review, we have initially performed a meta-analysis of keywords associated with the S protein to frame the outline of important research findings and directions related to it. Based on this outline, we have reviewed the structure, uniqueness, and origin of the S protein of SARS-CoV-2. Furthermore, the interactions of the Spike protein with host and its implications in COVID-19 pathogenesis, as well as drug and vaccine development, are discussed. We have also summarized the recent advances in detection methods using S protein-based RT-PCR, ELISA, point‐of‐care lateral flow immunoassay, and graphene-based field-effect transistor (FET) biosensors. Finally, we have also discussed the emerging Spike mutants and the efficacy of the Spike-based vaccines against those strains. Overall, we have covered most of the recent advances on the SARS-CoV-2 Spike protein and its possible implications in countering this virus.


Author(s):  
Lizhou Zhang ◽  
Cody B Jackson ◽  
Huihui Mou ◽  
Amrita Ojha ◽  
Erumbi S Rangarajan ◽  
...  

ABSTRACTSARS coronavirus 2 (SARS-CoV-2) isolates encoding a D614G mutation in the viral spike (S) protein predominate over time in locales where it is found, implying that this change enhances viral transmission. We therefore compared the functional properties of the S proteins with aspartic acid (SD614) and glycine (SG614) at residue 614. We observed that retroviruses pseudotyped with SG614 infected ACE2-expressing cells markedly more efficiently than those with SD614. This greater infectivity was correlated with less S1 shedding and greater incorporation of the S protein into the pseudovirion. Similar results were obtained using the virus-like particles produced with SARS-CoV-2 M, N, E, and S proteins. However, SG614 did not bind ACE2 more efficiently than SD614, and the pseudoviruses containing these S proteins were neutralized with comparable efficiencies by convalescent plasma. These results show SG614 is more stable than SD614, consistent with epidemiological data suggesting that viruses with SG614 transmit more efficiently.


2020 ◽  
Author(s):  
Xianlin Yuan ◽  
liangping li

AbstractSARS-CoV-2 has rapidly transmitted worldwide and results in the COVID-19 pandemic. Spike glycoprotein on surface is a key factor of viral transmission, and has appeared a lot of variants due to gene mutations, which may influence the viral antigenicity and vaccine efficacy. Here, we used bioinformatic tools to analyze B-cell epitopes of prototype S protein and its 9 common variants. 12 potential linear and 53 discontinuous epitopes of B-cells were predicted from the S protein prototype. Importantly, by comparing the epitope alterations between prototype and variants, we demonstrate that B-cell epitopes and antigenicity of 9 variants appear significantly different alterations. The dominant D614G variant impacts the potential epitope least, only with moderately elevated antigenicity, while the epitopes and antigenicity of some mutants(V483A, V367F, etc.) with small incidence in the population change greatly. These results suggest that the currently developed vaccines should be valid for a majority of SARS-CoV-2 infectors. This study provides a scientific basis for large-scale application of SARS-CoV-2 vaccines and for taking precautions against the probable appearance of antigen escape induced by genetic variation after vaccination.Author SummaryThe global pandemic of SARS-CoV-2 has lasted for more than half a year and has not yet been contained. Until now there is no effective treatment for SARS-CoV-2 caused disease (COVID-19). Successful vaccine development seems to be the only hope. However, this novel coronavirus belongs to the RNA virus, there is a high mutation rate in the genome, and these mutations often locate on the Spike proteins of virus, the gripper of the virus entering the cells. Vaccination induce the generation of antibodies, which block Spike protein. However, the Spike protein variants may change the recognition and binding of antibodies and make the vaccine ineffective. In this study, we predict neutralizing antibody recognition sites (B cell epitopes) of the prototype S protein of SARS-COV2, along with several common variants using bioinformatics tools. We discovered the variability in antigenicity among the mutants, for instance, in the more widespread D614G variant the change of epitope was least affected, only with slight increase of antigenicity. However, the antigenic epitopes of some mutants change greatly. These results could be of potential importance for future vaccine design and application against SARS-CoV2 variants.


2004 ◽  
Vol 78 (24) ◽  
pp. 13804-13811 ◽  
Author(s):  
Teri Hodgson ◽  
Rosa Casais ◽  
Brian Dove ◽  
Paul Britton ◽  
Dave Cavanagh

ABSTRACT We have replaced the ectodomain of the spike (S) protein of the Beaudette strain (Beau-R; apathogenic for Gallus domesticus chickens) of avian infectious bronchitis coronavirus (IBV) with that from the pathogenic M41 strain to produce recombinant IBV BeauR-M41(S). We have previously shown that this changed the tropism of the virus in vitro (R. Casais, B. Dove, D. Cavanagh, and P. Britton, J. Virol. 77:9084-9089, 2003). Herein we have assessed the pathogenicity and immunogenicity of BeauR-M41(S). There were no consistent differences in pathogenicity between the recombinant BeauR-M41(S) and its apathogenic parent Beau-R (based on snicking, nasal discharge, wheezing, watery eyes, rales, and ciliostasis in trachea), and both replicated poorly in trachea and nose compared to M41; the S protein from the pathogenic M41 had not altered the apathogenic nature of Beau-R. Both Beau-R and BeauR-M41(S) induced protection against challenge with M41 as assessed by absence of recovery of challenge virus and nasal exudate. With regard to snicking and ciliostasis, BeauR-M41(S) induced greater protection (seven out of nine chicks [77%]; assessed by ciliostasis) than Beau-R (one out of nine; 11%) but less than M41 (100%). The greater protection induced by BeauR-M41(S) against M41 may be related to the ectodomain of the spike protein of Beau-R differing from that of M41 by 4.1%; a small number of epitopes on the S protein may play a disproportionate role in the induction of immunity. The results are promising for the prospects of S-gene exchange for IBV vaccine development.


2020 ◽  
Vol 12 (02) ◽  
pp. 154-160
Author(s):  
Praveen Kumar Singh ◽  
Umay Kulsum ◽  
Syed Beenish Rufai ◽  
S. Rashmi Mudliar ◽  
Sarman Singh

Abstract Objectives The spread of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) virus has been unprecedentedly fast, spreading to more than 180 countries within 3 months with variable severity. One of the major reasons attributed to this variation is genetic mutation. Therefore, we aimed to predict the mutations in the spike protein (S) of the SARS-CoV-2 genomes available worldwide and analyze its impact on the antigenicity. Materials and Methods Several research groups have generated whole genome sequencing data which are available in the public repositories. A total of 1,604 spike proteins were extracted from 1,325 complete genome and 279 partial spike coding sequences of SARS-CoV-2 available in NCBI till May 1, 2020 and subjected to multiple sequence alignment to find the mutations corresponding to the reported single nucleotide polymorphisms (SNPs) in the genomic study. Further, the antigenicity of the predicted mutations inferred, and the epitopes were superimposed on the structure of the spike protein. Results The sequence analysis resulted in high SNPs frequency. The significant variations in the predicted epitopes showing high antigenicity were A348V, V367F and A419S in receptor binding domain (RBD). Other mutations observed within RBD exhibiting low antigenicity were T323I, A344S, R408I, G476S, V483A, H519Q, A520S, A522S and K529E. The RBD T323I, A344S, V367F, A419S, A522S and K529E are novel mutations reported first time in this study. Moreover, A930V and D936Y mutations were observed in the heptad repeat domain and one mutation D1168H was noted in heptad repeat domain 2. Conclusion S protein is the major target for vaccine development, but several mutations were predicted in the antigenic epitopes of S protein across all genomes available globally. The emergence of various mutations within a short period might result in the conformational changes of the protein structure, which suggests that developing a universal vaccine may be a challenging task.


Author(s):  
Sophie M. Jegouic ◽  
Silvia Loureiro ◽  
Michelle Thom ◽  
Deepa Paliwal ◽  
Ian M. Jones

AbstractThe newly emergent SARS-CoV-2 coronavirus is closely related to SARS-CoV which emerged in 2002. Studies on coronaviruses in general, and SARS in particular, have identified the virus spike protein (S) as being central to virus tropism, to the generation of a protective antibody response and to the unambiguous detection of past infections. As a result of this centrality SARS-CoV-2 S protein has a role in many aspects of research from vaccines to diagnostic tests. We describe a number of recombinant forms of SARS-CoV-2 S expressed in commonly available expression systems and their preliminary use in diagnostics and epitope mapping. These sources may find use in the current and future analysis of the virus and the Covid-19 disease it causes.


Sign in / Sign up

Export Citation Format

Share Document