scholarly journals Distinct Structural Flexibility within SARS-CoV-2 Spike Protein Reveals Potential Therapeutic Targets

Author(s):  
Serena H. Chen ◽  
M. Todd Young ◽  
John Gounley ◽  
Christopher Stanley ◽  
Debsindhu Bhowmik

AbstractThe emergence and rapid worldwide spread of the novel coronavirus disease, COVID-19, has prompted concerted efforts to find successful treatments. The causative virus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), uses its spike (S) protein to gain entry into host cells. Therefore, the S protein presents a viable target to develop a directed therapy. Here, we deployed an integrated artificial intelligence with molecular dynamics simulation approach to provide new details of the S protein structure. Based on a comprehensive structural analysis of S proteins from SARS-CoV-2 and previous human coronaviruses, we found that the protomer state of S proteins is structurally flexible. Without the presence of a stabilizing beta sheet from another protomer chain, two regions in the S2 domain and the hinge connecting the S1 and S2 subunits lose their secondary structures. Interestingly, the region in the S2 domain was previously identified as an immunodominant site in the SARS-CoV-1 S protein. We anticipate that the molecular details elucidated here will assist in effective therapeutic development for COVID-19.

eLife ◽  
2021 ◽  
Vol 10 ◽  
Author(s):  
Marloes Grobben ◽  
Karlijn van der Straten ◽  
Philip JM Brouwer ◽  
Mitch Brinkkemper ◽  
Pauline Maisonnasse ◽  
...  

Current SARS-CoV-2 vaccines are losing efficacy against emerging variants and may not protect against future novel coronavirus outbreaks, emphasizing the need for more broadly protective vaccines. To inform the development of a pan-coronavirus vaccine, we investigated the presence and specificity of cross-reactive antibodies against the spike (S) proteins of human coronaviruses (hCoV) after SARS-CoV-2 infection and vaccination. We found an 11- to 123-fold increase in antibodies binding to SARS-CoV and MERS-CoV as well as a 2- to 4-fold difference in antibodies binding to seasonal hCoVs in COVID-19 convalescent sera compared to pre-pandemic healthy donors, with the S2 subdomain of the S protein being the main target for cross-reactivity. In addition, we detected cross-reactive antibodies to all hCoV S proteins after SARS-CoV-2 vaccination in macaques and humans, with higher responses for hCoV more closely related to SARS-CoV-2. These findings support the feasibility of and provide guidance for development of a pan-coronavirus vaccine.


Author(s):  
Dima A. Sabbah ◽  
Rima Hajjo ◽  
Sanaa K. Bardaweel ◽  
Haizhen A. Zhong

: Coronaviruses (CoVs) are enveloped positive-stranded RNA viruses with spike (S) protein projections that allow the virus to enter and infect host cells. The S protein is a key virulence factor determining viral pathogenesis, host tropism, and disease pathogenesis. There are currently diverse corona viruses that are known to cause disease in humans. The occurrence of Middle East respiratory syndrome coronavirus (MERS-CoV) and Severe Acute Respiratory Syndrome coronavirus (SARS-CoV), as fatal human CoV diseases, has induced significant interest in the medical field. The novel coronavirus disease (COVID-19) is an infectious disease caused by a novel strain of coronavirus (SAR-CoV-2). The SARSCoV2 outbreak has been evolved in Wuhan, China, in December 2019, and identified as a pandemic on March 2020 resulting in 53.24 M cases and 1.20M deaths worldwide. SARS-CoV-2 main proteinase (MPro), a key protease of CoV-2, mediates viral replication and transcription. SARS-CoV-2 MPro has been emerged as an attractive target for SARS-CoV-2 drug design and development. Diverse scaffolds have been released targeting SARS-CoV-2 MPro. In this review, we culminate the latest published information about SARS-CoV-2 main proteinase (MPro) and reported inhibitors.


2021 ◽  
Author(s):  
Marloes Grobben ◽  
Karlijn van der Straten ◽  
Philip J.M. Brouwer ◽  
Mitch Brinkkemper ◽  
Pauline Maisonnasse ◽  
...  

Current SARS-CoV-2 vaccines are losing efficacy against emerging variants and may not protect against future novel coronavirus outbreaks, emphasizing the need for more broadly protective vaccines. To inform the development of a pan-coronavirus vaccine, we investigated the presence and specificity of cross-reactive antibodies against the spike (S) proteins of human coronaviruses (hCoV) after SARS-CoV-2 infection and vaccination. We found an 11 to 123-fold increase in antibodies binding to SARS-CoV and MERS-CoV as well as a 2 to 4-fold difference in antibodies binding to seasonal hCoVs in COVID-19 convalescent sera compared to pre-pandemic healthy donors, with the S2 subdomain of the S protein being the main target for cross-reactivity. In addition, we detected cross-reactive antibodies to all hCoV S proteins after SARS-CoV-2 S protein immunization in macaques, with higher responses for hCoV more closely related to SARS-CoV-2. These findings support the feasibility of and provide guidance for development of a pan-coronavirus vaccine.


2020 ◽  
Author(s):  
Rimjhim Dasgupta

The current outbreak of viral pneumonia in the city of Wuhan, China, was caused by a novel coronavirus designated 2019-nCoV, as determined by sequencing the viral RNA genome. Among its genome, S protein is surface-exposed and mediates entry into host cells. Currently it is one of the main targets for designing antibodies (Abs), therapeutic and vaccine. Earlier studies stated that ACE2 (angiotensin converting enzyme 2) could facilitate S protein mediated entry for this newly emerged coronavirus. Here we have taken an attempt to compare the genetic structure of receptor binding domain within S protein of highly pathogenic human coronaviruses (special reference to 2019-nCoV) with Bat coronavirus RaTG13. We have compared 2019-nCov receptor binding domain (RBD) with other pathogenic human coronaviruses (MERS-CoV and SARS-CoV) and Bat coronavirus RaTG13. We found that it is closest to RaTG13 RBD than MERS-CoV and SARS-CoV. Our study shows that 2019-nCov RBD also has significant identity with pangolin S protein RBD. We have also predicted the amino acid residues within RDB those may play important role for ACE2 receptor interaction. We identified unique signature for furin cleavage in 2019-nCov S protein but not in of other pathogenic human coronaviruses (tested here), bat coronavirus RaTG13 or pangolin.


2020 ◽  
Vol 6 (27) ◽  
pp. eabb9153 ◽  
Author(s):  
Xiaojun Li ◽  
Elena E. Giorgi ◽  
Manukumar Honnayakanahalli Marichannegowda ◽  
Brian Foley ◽  
Chuan Xiao ◽  
...  

COVID-19 has become a global pandemic caused by the novel coronavirus SARS-CoV-2. Understanding the origins of SARS-CoV-2 is critical for deterring future zoonosis, discovering new drugs, and developing a vaccine. We show evidence of strong purifying selection around the receptor binding motif (RBM) in the spike and other genes among bat, pangolin, and human coronaviruses, suggesting similar evolutionary constraints in different host species. We also demonstrate that SARS-CoV-2’s entire RBM was introduced through recombination with coronaviruses from pangolins, possibly a critical step in the evolution of SARS-CoV-2’s ability to infect humans. Similar purifying selection in different host species, together with frequent recombination among coronaviruses, suggests a common evolutionary mechanism that could lead to new emerging human coronaviruses.


eLife ◽  
2021 ◽  
Vol 10 ◽  
Author(s):  
Palur V Raghuvamsi ◽  
Nikhil Kumar Tulsian ◽  
Firdaus Samsudin ◽  
Xinlei Qian ◽  
Kiren Purushotorman ◽  
...  

The Spike (S) protein is the main handle for SARS-CoV-2 to enter host cells via surface ACE2 receptors. How ACE2 binding activates proteolysis of S protein is unknown. Here, using amide hydrogen-deuterium exchange mass spectrometry and molecular dynamics simulations, we have mapped the S:ACE2 interaction interface and uncovered long-range allosteric propagation of ACE2 binding to sites necessary for host-mediated proteolysis of S protein, critical for viral host entry. Unexpectedly, ACE2 binding enhances dynamics at a distal S1/S2 cleavage site and flanking protease docking site ~27 Å away while dampening dynamics of the stalk hinge (central helix and heptad repeat) regions ~130 Å away. This highlights that the stalk and proteolysis sites of the S protein are dynamic hotspots in the pre-fusion state. Our findings provide a dynamics map of the S:ACE2 interface in solution and also offer mechanistic insights into how ACE2 binding is allosterically coupled to distal proteolytic processing sites and viral-host membrane fusion. Our findings highlight protease docking sites flanking the S1/S2 cleavage site, fusion peptide and heptad repeat 1 (HR1) as alternate allosteric hotspot targets for potential therapeutic development.


2020 ◽  
Author(s):  
Xingyi Guo ◽  
Zhishan Chen ◽  
Yumin Xia ◽  
Weiqiang Lin ◽  
Hongzhi Li

Abstract Background: The outbreak of coronavirus disease (COVID-19) was caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), through its surface spike glycoprotein (S-protein) recognition on the receptor Angiotensin-converting enzyme 2 (ACE2) in humans. However, it remains unclear how genetic variations in ACE2 may affect its function and structure, and consequently alter the recognition by SARS-CoV-2. Methods: We have systemically characterized missense variants in the gene ACE2 using data from the Genome Aggregation Database (gnomAD; N = 141,456). To investigate the putative deleterious role of missense variants, six existing functional prediction tools were applied to evaluate their impact. We further analyzed the structural flexibility of ACE2 and its protein-protein interface with the S-protein of SARS-CoV-2 using our developed Legion Interfaces Analysis (LiAn) program.Results: Here, we characterized a total of 12 ACE2 putative deleterious missense variants. Of those 12 variants, we further showed that p.His378Arg could directly weaken the binding of catalytic metal atom to decrease ACE2 activity and p.Ser19Pro could distort the most important helix to the S-protein. Another seven missense variants may affect secondary structures (i.e. p.Gly211Arg; p.Asp206Gly; p.Arg219Cys; p.Arg219His, p.Lys341Arg, p.Ile468Val, and p.Ser547Cys), whereas p.Ile468Val with AF = 0.01 is only present in Asian.Conclusions: We provide strong evidence of putative deleterious missense variants in ACE2 that are present in specific populations, which could disrupt the function and structure of ACE2. These findings provide novel insight into the genetic variation in ACE2 which may affect the SARS-CoV-2 recognition and infection, and COVID-19 susceptibility and treatment.


2020 ◽  
Vol 3 (1) ◽  
Author(s):  
Pranam Chatterjee ◽  
Manvitha Ponnapati ◽  
Christian Kramme ◽  
Alexandru M. Plesa ◽  
George M. Church ◽  
...  

AbstractThe COVID-19 pandemic, caused by the novel coronavirus SARS-CoV-2, has elicited a global health crisis of catastrophic proportions. With only a few vaccines approved for early or limited use, there is a critical need for effective antiviral strategies. In this study, we report a unique antiviral platform, through computational design of ACE2-derived peptides which both target the viral spike protein receptor binding domain (RBD) and recruit E3 ubiquitin ligases for subsequent intracellular degradation of SARS-CoV-2 in the proteasome. Our engineered peptide fusions demonstrate robust RBD degradation capabilities in human cells and are capable of inhibiting infection-competent viral production, thus prompting their further experimental characterization and therapeutic development.


2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Jinsung Yang ◽  
Simon J. L. Petitjean ◽  
Melanie Koehler ◽  
Qingrong Zhang ◽  
Andra C. Dumitru ◽  
...  

Abstract Study of the interactions established between the viral glycoproteins and their host receptors is of critical importance for a better understanding of virus entry into cells. The novel coronavirus SARS-CoV-2 entry into host cells is mediated by its spike glycoprotein (S-glycoprotein), and the angiotensin-converting enzyme 2 (ACE2) has been identified as a cellular receptor. Here, we use atomic force microscopy to investigate the mechanisms by which the S-glycoprotein binds to the ACE2 receptor. We demonstrate, both on model surfaces and on living cells, that the receptor binding domain (RBD) serves as the binding interface within the S-glycoprotein with the ACE2 receptor and extract the kinetic and thermodynamic properties of this binding pocket. Altogether, these results provide a picture of the established interaction on living cells. Finally, we test several binding inhibitor peptides targeting the virus early attachment stages, offering new perspectives in the treatment of the SARS-CoV-2 infection.


Cells ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 1962
Author(s):  
Muhammad Aslam ◽  
Yury Ladilov

An outbreak of the novel coronavirus (CoV) SARS-CoV-2, the causative agent of COVID-19 respiratory disease, infected millions of people since the end of 2019, led to high-level morbidity and mortality and caused worldwide social and economic disruption. There are currently no antiviral drugs available with proven efficacy or vaccines for its prevention. An understanding of the underlying cellular mechanisms involved in virus replication is essential for repurposing the existing drugs and/or the discovery of new ones. Endocytosis is the important mechanism of entry of CoVs into host cells. Endosomal maturation followed by the fusion with lysosomes are crucial events in endocytosis. Late endosomes and lysosomes are characterized by their acidic pH, which is generated by a proton transporter V-ATPase and required for virus entry via endocytic pathway. The cytoplasmic cAMP pool produced by soluble adenylyl cyclase (sAC) promotes V-ATPase recruitment to endosomes/lysosomes and thus their acidification. In this review, we discuss targeting the sAC-specific cAMP pool as a potential strategy to impair the endocytic entry of the SARS-CoV-2 into the host cell. Furthermore, we consider the potential impact of sAC inhibition on CoV-induced disease via modulation of autophagy and apoptosis.


Sign in / Sign up

Export Citation Format

Share Document