Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 601
Filtrar
1.
PLoS One ; 15(11): e0241168, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33170884

RESUMO

The SARS-CoV-2 virion responsible for the current world-wide pandemic COVID-19 has a characteristic Spike protein (S) on its surface that embellishes both a prefusion state and fusion state. The prefusion Spike protein (S) is a large trimeric protein where each protomer may be in a so-called Up state or Down state, depending on the configuration of its receptor binding domain (RBD) within its distal, prefusion S1 domain. The Up state is believed to allow binding of the virion to ACE-2 receptors on human epithelial cells, whereas the Down state is believed to be relatively inactive or reduced in its binding behavior. We have performed detailed all-atom, dominant energy landscape mappings for noncovalent interactions (charge, partial charge, and van der Waals) of the SARS-CoV-2 Spike protein in its static prefusion state based on two recent and independent experimental structure publications. We included both interchain interactions and intrachain (domain) interactions in our mappings in order to determine any telling differences (different so-called "glue" points) between residues in the Up and Down state protomers. The S2 proximal, fusion domain demonstrated no appreciable energetic differences between Up and Down protomers, including interchain as well as each protomer's intrachain, S1-S2 interactions. However, the S1 domain interactions across neighboring protomers, which include the RBD-NTD cross chain interactions, showed significant energetic differences between Up-Down and Down-Down neighboring protomers. This included, for example, a key RBD residue ARG357 in the Up-Down interaction and a three residue sequence ALA520-PRO521-ALA522, associated with a turn structure in the RBD of the Up state protomer, acting as a stabilizing interaction with the NTD of its neighbor protomer. Additionally, our intra chain dominant energy mappings within each protomer, identified a significant "glue" point or possible "latch" for the Down state protomer between the S1 subdomain, SD1, and the RBD domain of the same protomer that was completely missing in the Up state protomer analysis. Ironically, this dominant energetic interaction in the Down state protomer involved the backbone atoms of the same three residue sequence ALA520-PRO521-ALA522 of the RBD with the amino acid R-group of GLN564 in the SD1 domain. Thus, this same three residue sequence acts as a stabilizer of the RBD in the Up conformation through its interactions with its neighboring NTD chain and a kind of latch in the Down state conformation through its interactions with its own SD1 domain. The dominant interaction energy residues identified here are also conserved across reported variations of SARS-CoV-2, as well as the closely related virions SARS-Cov and the bat corona virus RatG13. We conducted preliminary molecular dynamics simulations across 0.1 µ seconds to see if this latch provided structural stability and indeed found that a single point mutation (Q564G) resulted in the latch releasing transforming the protomer from the Down to the Up state conformation. Full trimeric Spike protein studies of the same mutation across all protomers, however, did not exhibit latch release demonstrating the critical importance of interchain interactions across the S1 domain, including RBD-NTD neighboring chain interactions. Therapies aimed at disrupting these noncovalent interactions could be a viable route for the physico-chemical mitigation of this deadly virion.


Assuntos
Betacoronavirus/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo , Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/patologia , Infecções por Coronavirus/virologia , Humanos , Simulação de Dinâmica Molecular , Pandemias , Peptidil Dipeptidase A/química , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/patologia , Pneumonia Viral/virologia , Mutação Puntual , Ligação Proteica , Domínios Proteicos , Estabilidade Proteica , Subunidades Proteicas/química , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Termodinâmica
2.
PLoS One ; 15(11): e0240345, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33170902

RESUMO

In late December 2019, an emerging viral infection COVID-19 was identified in Wuhan, China, and became a global pandemic. Characterization of the genetic variants of SARS-CoV-2 is crucial in following and evaluating it spread across countries. In this study, we collected and analyzed 3,067 SARS-CoV-2 genomes isolated from 55 countries during the first three months after the onset of this virus. Using comparative genomics analysis, we traced the profiles of the whole-genome mutations and compared the frequency of each mutation in the studied population. The accumulation of mutations during the epidemic period with their geographic locations was also monitored. The results showed 782 variants sites, of which 512 (65.47%) had a non-synonymous effect. Frequencies of mutated alleles revealed the presence of 68 recurrent mutations, including ten hotspot non-synonymous mutations with a prevalence higher than 0.10 in this population and distributed in six SARS-CoV-2 genes. The distribution of these recurrent mutations on the world map revealed that certain genotypes are specific to geographic locations. We also identified co-occurring mutations resulting in the presence of several haplotypes. Moreover, evolution over time has shown a mechanism of mutation co-accumulation which might affect the severity and spread of the SARS-CoV-2. The phylogentic analysis identified two major Clades C1 and C2 harboring mutations L3606F and G614D, respectively and both emerging for the first time in China. On the other hand, analysis of the selective pressure revealed the presence of negatively selected residues that could be taken into considerations as therapeutic targets. We have also created an inclusive unified database (http://covid-19.medbiotech.ma) that lists all of the genetic variants of the SARS-CoV-2 genomes found in this study with phylogeographic analysis around the world.


Assuntos
Betacoronavirus/genética , Variação Genética , Genoma Viral , Betacoronavirus/classificação , Betacoronavirus/isolamento & purificação , China , Infecções por Coronavirus/patologia , Infecções por Coronavirus/virologia , Evolução Molecular , Humanos , Pandemias , Filogenia , Pneumonia Viral/patologia , Pneumonia Viral/virologia , Estrutura Terciária de Proteína , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Proteínas Virais/química , Proteínas Virais/genética
3.
J Mol Model ; 26(12): 338, 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33175236

RESUMO

A novel coronavirus (SARS-CoV-2) identified in Wuhan state of China in 2019 is the causative agent of deadly disease COVID-19. It has spread across the globe (more than 210 countries) within a short period. Coronaviruses pose serious health threats to both humans and animals. A recent publication reported an experimental 3D complex structure of the S protein of SARS-CoV-2 showed that the ectodomain of the SARS-CoV-2 S protein binds to the peptidase domain (PD) of human ACE2 with a dissociation constant (Kd) of ~ 15 nM. In this study, we focused on inhibitors for ACE2: S protein complex using virtual screening and inhibition studies through molecular docking for over 200,000 natural compounds. Toxicity analysis was also performed for the best hits, and the final complex structures for four complexes were subjected to 400 ns molecular dynamics simulations for stability testing. We found two natural origin inhibitors for the S protein: human ACE2 complex (Andrographolide and Pterostilbene) which displayed better inhibition potential for ACE2 receptor and its binding with the S protein of SARS-CoV-2. Comparative studies were also performed to test and verify that these two drug candidates are also better than hydroxychloroquine which is known to inhibit this complex. However, we needed better potential drug candidates to overcome the side effects of hydroxychloroquine. Supplementary experimental studies need to be carried forward to corroborate the viability of these two new inhibitors for ACE2: S protein complex so as to curb down COVID-19.


Assuntos
Betacoronavirus/fisiologia , Infecções por Coronavirus/epidemiologia , Peptídeo Hidrolases/metabolismo , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/epidemiologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Betacoronavirus/genética , Infecções por Coronavirus/virologia , Reposicionamento de Medicamentos , Humanos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Pandemias , Peptídeo Hidrolases/genética , Peptidil Dipeptidase A/genética , Pneumonia Viral/virologia , Domínios Proteicos , Glicoproteína da Espícula de Coronavírus/genética
4.
Vaccine ; 38(48): 7612-7628, 2020 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-33082015

RESUMO

SARS-CoV-2 causes a severe respiratory disease called COVID-19. Currently, global health is facing its devastating outbreak. However, there is no vaccine available against this virus up to now. In this study, a novel multi-epitope vaccine against SARS-CoV-2 was designed to provoke both innate and adaptive immune responses. The immunodominant regions of six non-structural proteins (nsp7, nsp8, nsp9, nsp10, nsp12 and nsp14) of SARS-CoV-2 were selected by multiple immunoinformatic tools to provoke T cell immune response. Also, immunodominant fragment of the functional region of SARS-CoV-2 spike (400-510 residues) protein was selected for inducing neutralizing antibodies production. The selected regions' sequences were connected to each other by furin-sensitive linker (RVRR). Moreover, the functional region of ß-defensin as a well-known agonist for the TLR-4/MD complex was added at the N-terminus of the vaccine using (EAAAK)3 linker. Also, a CD4 + T-helper epitope, PADRE, was used at the C-terminal of the vaccine by GPGPG and A(EAAAK)2A linkers to form the final vaccine construct. The physicochemical properties, allergenicity, antigenicity, functionality and population coverage of the final vaccine construct were analyzed. The final vaccine construct was an immunogenic, non-allergen and unfunctional protein which contained multiple CD8 + and CD4 + overlapping epitopes, IFN-γ inducing epitopes, linear and conformational B cell epitopes. It could form stable and significant interactions with TLR-4/MD according to molecular docking and dynamics simulations. Global population coverage of the vaccine for HLA-I and II were estimated 96.2% and 97.1%, respectively. At last, the final vaccine construct was reverse translated to design the DNA vaccine. Although the designed vaccine exhibited high efficacy in silico, further experimental validation is necessary.


Assuntos
Anticorpos Antivirais/biossíntese , Betacoronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Glicoproteína da Espícula de Coronavírus/imunologia , Proteínas não Estruturais Virais/imunologia , Vacinas Virais/biossíntese , Sequência de Aminoácidos , Betacoronavirus/patogenicidade , Biologia Computacional , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/genética , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/metabolismo , Infecções por Coronavirus/virologia , Epitopos de Linfócito B/química , Epitopos de Linfócito B/genética , Epitopos de Linfócito B/imunologia , Epitopos de Linfócito T/química , Epitopos de Linfócito T/genética , Epitopos de Linfócito T/imunologia , Antígenos de Histocompatibilidade Classe I/química , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe II/química , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/imunologia , Humanos , Imunidade Inata/efeitos dos fármacos , Imunogenicidade da Vacina , Simulação de Acoplamento Molecular , Pneumonia Viral/epidemiologia , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , Ligação Proteica , Estrutura Secundária de Proteína , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Vacinas Atenuadas , Vacinas de DNA , Vacinas de Subunidades , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/genética , Vacinas Virais/genética , Vacinas Virais/metabolismo
5.
Cell Rep ; 33(5): 108352, 2020 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-33113345

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is constantly evolving. Prior studies focused on high-case-density locations, such as the northern and western metropolitan areas of the United States. This study demonstrates continued SARS-CoV-2 evolution in a suburban southern region of the United States by high-density amplicon sequencing of symptomatic cases. 57% of strains carry the spike D614G variant, which is associated with higher genome copy numbers, and its prevalence expands with time. Four strains carry a deletion in a predicted stem loop of the 3' UTR. The data are consistent with community spread within local populations and the larger continental United States. The data instill confidence in current testing sensitivity and validate "testing by sequencing" as an option to uncover cases, particularly nonstandard coronavirus disease 2019 (COVID-19) clinical presentations. This study contributes to the understanding of COVID-19 through an extensive set of genomes from a non-urban setting and informs vaccine design by defining D614G as a dominant and emergent SARS-CoV-2 isolate in the United States.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão , Glicoproteína da Espícula de Coronavírus/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Pandemias , Filogenia , Estados Unidos
6.
Emerg Microbes Infect ; 9(1): 2361-2367, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33118859

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic is still ongoing and has become an important public health threat. This disease is caused by a new coronavirus named severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection, and so far, little is known about this virus. In this study, by using plaque purification, we purified two SARS-CoV-2 virus strains from the same specimen, one named F8 containing a 12-bp deletion in the E gene and the other named 8X containing the wild-type E gene. There was no significant difference in the viral titer and infectivity of these two strains. The S protein content of the F8 viral culture was 0.39 µg/ml, much higher than that of 8X. An inactivated vaccine made from the F8 strain could trigger high levels of the IgG titer and neutralizing antibody titer, which could last for at least 6 weeks and were significantly higher than those from the 8X strain at 1 and 3 weeks post vaccination, respectively. In conclusion, we reported that both the E gene mutant and wild-type SARS-CoV-2 strains were isolated from the same clinical sample by plaque purification. A 12-bp deletion in the E gene was important for SARS-CoV-2 replication and immunogenicity.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/virologia , Pneumonia Viral/virologia , Proteínas do Envelope Viral/genética , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Betacoronavirus/imunologia , Betacoronavirus/patogenicidade , Infecções por Coronavirus/epidemiologia , Feminino , Humanos , Imunização , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pandemias , Pneumonia Viral/epidemiologia , Deleção de Sequência , Glicoproteína da Espícula de Coronavírus/administração & dosagem , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Proteínas do Envelope Viral/administração & dosagem , Proteínas do Envelope Viral/imunologia , Virulência
8.
Vaccine ; 38(47): 7533-7541, 2020 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-33039209

RESUMO

We developed a severe acute respiratory syndrome (SARS) subunit recombinant protein vaccine candidate based on a high-yielding, yeast-engineered, receptor-binding domain (RBD219-N1) of the SARS beta-coronavirus (SARS-CoV) spike (S) protein. When formulated with Alhydrogel®, RBD219-N1 induced high levels of neutralizing antibodies against both pseudotyped virus and a clinical (mouse-adapted) isolate of SARS-CoV. Here, we report that mice immunized with RBD219-N1/Alhydrogel® were fully protected from lethal SARS-CoV challenge (0% mortality), compared to ~30% mortality in mice immunized with the SARS S protein formulated with Alhydrogel®, and 100% mortality in negative controls. An RBD219-N1 formulation with Alhydrogel® was also superior to the S protein, unadjuvanted RBD, and AddaVax (MF59-like adjuvant)-formulated RBD in inducing specific antibodies and preventing cellular infiltrates in the lungs upon SARS-CoV challenge. Specifically, a formulation with a 1:25 ratio of RBD219-N1 to Alhydrogel® provided high neutralizing antibody titers, 100% protection with non-detectable viral loads with minimal or no eosinophilic pulmonary infiltrates. As a result, this vaccine formulation is under consideration for further development against SARS-CoV and potentially other emerging and re-emerging beta-CoVs such as SARS-CoV-2.


Assuntos
Betacoronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas de Subunidades/imunologia , Vacinas Sintéticas/imunologia , Vacinas Virais/imunologia , Hidróxido de Alumínio/administração & dosagem , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Infecções por Coronavirus/imunologia , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Domínios Proteicos/imunologia , Proteínas Recombinantes/imunologia , Síndrome Respiratória Aguda Grave/prevenção & controle , Glicoproteína da Espícula de Coronavírus/genética , Carga Viral/imunologia
9.
PLoS One ; 15(10): e0241172, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33091066

RESUMO

The novel coronavirus 2019 (COVID-19) global pandemic has drastically affected the world economy, raised public anxiety, and placed a substantial psychological burden on the governments and healthcare professionals by affecting over 4.7 million people worldwide. As a preventive measure to minimise the risk of community transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in India, a nationwide lockdown was imposed initially for 21 days to limit the movement of 1.3 billion people. These restrictions continue in most areas, with a conditional relaxation occurring in a few Indian states. In an attempt to assess the emerging mutants of SARS-CoV-2 and determine their spread in India, we analysed 112 complete genomes of SARS-CoV-2 in a time-lapse manner. We found 72 distinct SARS-CoV-2 haplotypes, defined by 143 polymorphic sites and high haplotype diversity, suggesting that this virus possesses a high evolutionary potential. We also demonstrated that early introduction of SARS-CoV-2 into India was from China, Italy and Iran and observed signs of community spread of the virus following its rapid demographic expansion since its first outbreak in the country. Additionally, we identified 18 mutations in the SARS-CoV-2 spike glycoprotein and a few selected mutations showed to increase stability, binding affinity, and molecular flexibility in the overall tertiary structure of the protein that may facilitate interaction between the receptor binding domain (RBD) of spike protein and the human angiotensin-converting enzyme 2 (ACE2) receptor. The study provides a pragmatic view of haplotype-dependent spread of SARS-CoV-2 in India which could be important in tailoring the pharmacologic treatments to be more effective for those infected with the most common haplotypes. The findings based on the time-lapse sentinel surveillance of SARS-CoV-2 will aid in the development of a real-time practical framework to tackle the ongoing, fast-evolving epidemic challenges in the country.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão , Vigilância de Evento Sentinela , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/virologia , Genoma Viral/genética , Haplótipos , Humanos , Índia/epidemiologia , Simulação de Acoplamento Molecular , Mutação , Pandemias/prevenção & controle , Peptidil Dipeptidase A/metabolismo , Filogenia , Pneumonia Viral/prevenção & controle , Pneumonia Viral/virologia , Polimorfismo Genético , Estrutura Terciária de Proteína , Quarentena/métodos , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo
10.
mBio ; 11(6)2020 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-33127862

RESUMO

We sequenced the genomes of 5,085 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strains causing two coronavirus disease 2019 (COVID-19) disease waves in metropolitan Houston, TX, an ethnically diverse region with 7 million residents. The genomes were from viruses recovered in the earliest recognized phase of the pandemic in Houston and from viruses recovered in an ongoing massive second wave of infections. The virus was originally introduced into Houston many times independently. Virtually all strains in the second wave have a Gly614 amino acid replacement in the spike protein, a polymorphism that has been linked to increased transmission and infectivity. Patients infected with the Gly614 variant strains had significantly higher virus loads in the nasopharynx on initial diagnosis. We found little evidence of a significant relationship between virus genotype and altered virulence, stressing the linkage between disease severity, underlying medical conditions, and host genetics. Some regions of the spike protein-the primary target of global vaccine efforts-are replete with amino acid replacements, perhaps indicating the action of selection. We exploited the genomic data to generate defined single amino acid replacements in the receptor binding domain of spike protein that, importantly, produced decreased recognition by the neutralizing monoclonal antibody CR3022. Our report represents the first analysis of the molecular architecture of SARS-CoV-2 in two infection waves in a major metropolitan region. The findings will help us to understand the origin, composition, and trajectory of future infection waves and the potential effect of the host immune response and therapeutic maneuvers on SARS-CoV-2 evolution.IMPORTANCE There is concern about second and subsequent waves of COVID-19 caused by the SARS-CoV-2 coronavirus occurring in communities globally that had an initial disease wave. Metropolitan Houston, TX, with a population of 7 million, is experiencing a massive second disease wave that began in late May 2020. To understand SARS-CoV-2 molecular population genomic architecture and evolution and the relationship between virus genotypes and patient features, we sequenced the genomes of 5,085 SARS-CoV-2 strains from these two waves. Our report provides the first molecular characterization of SARS-CoV-2 strains causing two distinct COVID-19 disease waves.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/virologia , Pneumonia Viral/virologia , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Sequência de Aminoácidos , Substituição de Aminoácidos , Anticorpos Neutralizantes/imunologia , Sequência de Bases , Betacoronavirus/imunologia , Técnicas de Laboratório Clínico , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/imunologia , Genoma Viral , Genótipo , Humanos , Aprendizado de Máquina , Modelos Moleculares , Técnicas de Diagnóstico Molecular , Pandemias , Filogenia , Pneumonia Viral/epidemiologia , Pneumonia Viral/imunologia , RNA Replicase/química , RNA Replicase/genética , Análise de Sequência de Proteína , Glicoproteína da Espícula de Coronavírus/imunologia , Texas/epidemiologia , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/genética
12.
Sci Rep ; 10(1): 17698, 2020 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-33077899

RESUMO

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is responsible for the ongoing global outbreak of coronavirus disease (COVID-19) which is a significant threat to global public health. The rapid spread of COVID-19 necessitates the development of cost-effective technology platforms for the production of vaccines, drugs, and protein reagents for appropriate disease diagnosis and treatment. In this study, we explored the possibility of producing the receptor binding domain (RBD) of SARS-CoV-2 and an anti-SARS-CoV monoclonal antibody (mAb) CR3022 in Nicotiana benthamiana. Both RBD and mAb CR3022 were transiently produced with the highest expression level of 8 µg/g and 130 µg/g leaf fresh weight respectively at 3 days post-infiltration. The plant-produced RBD exhibited specific binding to the SARS-CoV-2 receptor, angiotensin-converting enzyme 2 (ACE2). Furthermore, the plant-produced mAb CR3022 binds to SARS-CoV-2, but fails to neutralize the virus in vitro. This is the first report showing the production of anti-SARS-CoV-2 RBD and mAb CR3022 in plants. Overall these findings provide a proof-of-concept for using plants as an expression system for the production of SARS-CoV-2 antigens and antibodies or similar other diagnostic reagents against SARS-CoV-2 rapidly, especially during epidemic or pandemic situation.


Assuntos
Anticorpos Monoclonais/metabolismo , Anticorpos Antivirais/metabolismo , Betacoronavirus/metabolismo , Tabaco/metabolismo , Animais , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/genética , Anticorpos Antivirais/imunologia , Chlorocebus aethiops , Infecções por Coronavirus/patologia , Infecções por Coronavirus/virologia , Humanos , Testes de Neutralização , Pandemias , Peptidil Dipeptidase A/química , Peptidil Dipeptidase A/metabolismo , Folhas de Planta/metabolismo , Pneumonia Viral/patologia , Pneumonia Viral/virologia , Ligação Proteica , Domínios Proteicos/imunologia , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/isolamento & purificação , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Células Vero
13.
Sci Rep ; 10(1): 16944, 2020 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-33037310

RESUMO

The Spike protein of the novel coronavirus SARS-CoV2 contains an insertion 680SPRRAR↓SV687 forming a cleavage motif RxxR for furin-like enzymes at the boundary of S1/S2 subunits. Cleavage at S1/S2 is important for efficient viral entry into target cells. The insertion is absent in other CoV-s of the same clade, including SARS-CoV1 that caused the 2003 outbreak. However, an analogous cleavage motif was present at S1/S2 of the Spike protein of the more distant Middle East Respiratory Syndrome coronavirus MERS-CoV. We show that a crucial third arginine at the left middle position, comprising a motif RRxR is required for furin recognition in vitro, while the general motif RxxR in common with MERS-CoV is not sufficient for cleavage. Further, we describe a surprising finding that the two serines at the edges of the insert SPRRAR↓SV can be efficiently phosphorylated by proline-directed and basophilic protein kinases. Both phosphorylations switch off furin's ability to cleave the site. Although phospho-regulation of secreted proteins is still poorly understood, further studies, supported by a recent report of ten in vivo phosphorylated sites in the Spike protein of SARS-CoV2, could potentially uncover important novel regulatory mechanisms for SARS-CoV2.


Assuntos
Betacoronavirus/genética , Coronavírus da Síndrome Respiratória do Oriente Médio/genética , Vírus da SARS/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Motivos de Aminoácidos/genética , Sequência de Aminoácidos , Furina/metabolismo , Fosforilação , Proteólise , Glicoproteína da Espícula de Coronavírus/genética , Internalização do Vírus
14.
Arch Virol ; 165(12): 2937-2944, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33025199

RESUMO

SARS-CoV-2 was first detected in the city of Wuhan, Hubei Province, China. In this study, we identified 11 unique mutations in viral SARS-COV-2 isolates from Turkey. Nine of them cause structural alterations in the S protein, nsp2, nsp3, nsp4 and nsp12 regions. The mutations identified here might have significant functional implications that need to be addressed in future studies in the context of vaccine engineering and therapeutic interventions. Moreover, transmission and phylogenetic analysis revealed multiple independent sources of introductions of SARS-CoV-2 into Turkey and a close relationship to the isolates from Saudi Arabia.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Pandemias , Pneumonia Viral/diagnóstico , Pneumonia Viral/epidemiologia , Mutação Puntual , Glicoproteína da Espícula de Coronavírus/genética , Sequência de Aminoácidos , Substituição de Aminoácidos , Betacoronavirus/classificação , Betacoronavirus/isolamento & purificação , Betacoronavirus/patogenicidade , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Humanos , Filogenia , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Turquia/epidemiologia
15.
Sci Rep ; 10(1): 18149, 2020 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-33097791

RESUMO

Antigens displayed on self-assembling nanoparticles can stimulate strong immune responses and have been playing an increasingly prominent role in structure-based vaccines. However, the development of such immunogens is often complicated by inefficiencies in their production. To alleviate this issue, we developed a plug-and-play platform using the spontaneous isopeptide-bond formation of the SpyTag:SpyCatcher system to display trimeric antigens on self-assembling nanoparticles, including the 60-subunit Aquifex aeolicus lumazine synthase (LuS) and the 24-subunit Helicobacter pylori ferritin. LuS and ferritin coupled to SpyTag expressed well in a mammalian expression system when an N-linked glycan was added to the nanoparticle surface. The respiratory syncytial virus fusion (F) glycoprotein trimer-stabilized in the prefusion conformation and fused with SpyCatcher-could be efficiently conjugated to LuS-SpyTag or ferritin-SpyTag, enabling multivalent display of F trimers with prefusion antigenicity. Similarly, F-glycoprotein trimers from human parainfluenza virus-type 3 and spike-glycoprotein trimers from SARS-CoV-2 could be displayed on LuS nanoparticles with decent yield and antigenicity. Notably, murine vaccination with 0.08 µg of SARS-CoV-2 spike-LuS nanoparticle elicited similar neutralizing responses as 2.0 µg of spike, which was ~ 25-fold higher on a weight-per-weight basis. The versatile platform described here thus allows for multivalent plug-and-play presentation on self-assembling nanoparticles of trimeric viral antigens, with SARS-CoV-2 spike-LuS nanoparticles inducing particularly potent neutralizing responses.


Assuntos
Antígenos/imunologia , Betacoronavirus/metabolismo , Nanopartículas/química , Glicoproteína da Espícula de Coronavírus/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Antígenos/genética , Antígenos/metabolismo , Bactérias/enzimologia , Proteínas de Bactérias/genética , Betacoronavirus/isolamento & purificação , Infecções por Coronavirus , Ferritinas/genética , Helicobacter pylori/metabolismo , Humanos , Camundongos , Complexos Multienzimáticos/genética , Testes de Neutralização , Pandemias , Pneumonia Viral , Multimerização Proteica , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Propriedades de Superfície
16.
Sci Rep ; 10(1): 18289, 2020 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-33106569

RESUMO

The World Health Organization characterized COVID-19 as a pandemic in March 2020, the second pandemic of the twenty-first century. Expanding virus populations, such as that of SARS-CoV-2, accumulate a number of narrowly shared polymorphisms, imposing a confounding effect on traditional clustering methods. In this context, approaches that reduce the complexity of the sequence space occupied by the SARS-CoV-2 population are necessary for robust clustering. Here, we propose subdividing the global SARS-CoV-2 population into six well-defined subtypes and 10 poorly represented genotypes named tentative subtypes by focusing on the widely shared polymorphisms in nonstructural (nsp3, nsp4, nsp6, nsp12, nsp13 and nsp14) cistrons and structural (spike and nucleocapsid) and accessory (ORF8) genes. The six subtypes and the additional genotypes showed amino acid replacements that might have phenotypic implications. Notably, three mutations (one of them in the Spike protein) were responsible for the geographical segregation of subtypes. We hypothesize that the virus subtypes detected in this study are records of the early stages of SARS-CoV-2 diversification that were randomly sampled to compose the virus populations around the world. The genetic structure determined for the SARS-CoV-2 population provides substantial guidelines for maximizing the effectiveness of trials for testing candidate vaccines or drugs.


Assuntos
Betacoronavirus/genética , Polimorfismo Genético , Betacoronavirus/classificação , Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/patologia , Infecções por Coronavirus/virologia , Genótipo , Humanos , Proteínas do Nucleocapsídeo/genética , Pandemias , Filogenia , Pneumonia Viral/epidemiologia , Pneumonia Viral/patologia , Pneumonia Viral/virologia , Glicoproteína da Espícula de Coronavírus/genética , Proteínas não Estruturais Virais/genética , Proteínas Virais/genética
17.
Signal Transduct Target Ther ; 5(1): 237, 2020 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-33051445

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an emerging virus that is highly pathogenic and has caused the recent worldwide pandemic officially named coronavirus disease (COVID-19). Currently, considerable efforts have been put into developing effective and safe drugs and vaccines against SARS-CoV-2. Vaccines, such as inactivated vaccines, nucleic acid-based vaccines, and vector vaccines, have already entered clinical trials. In this review, we provide an overview of the experimental and clinical data obtained from recent SARS-CoV-2 vaccines trials, and highlight certain potential safety issues that require consideration when developing vaccines. Furthermore, we summarize several strategies utilized in the development of vaccines against other infectious viruses, such as severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV), with the aim of aiding in the design of effective therapeutic approaches against SARS-CoV-2.


Assuntos
Anticorpos Antivirais/biossíntese , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Peptidil Dipeptidase A/genética , Pneumonia Viral/prevenção & controle , Receptores Virais/genética , Vacinas Virais/biossíntese , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/imunologia , Betacoronavirus/patogenicidade , Ensaios Clínicos como Assunto , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Imunidade Inata/efeitos dos fármacos , Esquemas de Imunização , Imunogenicidade da Vacina , Coronavírus da Síndrome Respiratória do Oriente Médio/efeitos dos fármacos , Coronavírus da Síndrome Respiratória do Oriente Médio/imunologia , Coronavírus da Síndrome Respiratória do Oriente Médio/patogenicidade , Segurança do Paciente , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , Ligação Proteica , Receptores Virais/antagonistas & inibidores , Receptores Virais/metabolismo , Vírus da SARS/efeitos dos fármacos , Vírus da SARS/imunologia , Vírus da SARS/patogenicidade , Síndrome Respiratória Aguda Grave/imunologia , Síndrome Respiratória Aguda Grave/prevenção & controle , Síndrome Respiratória Aguda Grave/virologia , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Vacinas Atenuadas , Vacinas de DNA , Vacinas de Subunidades , Vacinas de Partículas Semelhantes a Vírus , Vacinas Virais/administração & dosagem
18.
Vaccine ; 38(46): 7205-7212, 2020 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-33010978

RESUMO

The development of an effective vaccine against SARS-CoV-2 is urgently needed. We generated SARS-CoV-2 RBD-Fc fusion protein and evaluated its potency to elicit neutralizing antibody response in mice. RBD-Fc elicited a higher neutralizing antibodies titer than RBD as evaluated by a pseudovirus neutralization assay and a live virus based microneutralization assay. Furthermore, RBD-Fc immunized sera better inhibited cell-cell fusion, as evaluated by a quantitative cell-cell fusion assay. The cell-cell fusion assay results correlated well with the virus neutralization potency and could be used for high-throughput screening of large panels of anti-SARS-CoV-2 antibodies and vaccines without the requirement of live virus infection in BSL3 containment. Moreover, the anti-RBD sera did not enhance the pseudotyped SARS-CoV-2 infection of K562 cells. These results demonstrate that Fc fusion can significantly improve the humoral immune response to recombinant RBD immunogen, and suggest that RBD-Fc could serve as a useful component of effective vaccines against SARS-CoV-2.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Infecções por Coronavirus/prevenção & controle , Fragmentos Fc das Imunoglobulinas/imunologia , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Betacoronavirus/imunologia , Fusão Celular , Linhagem Celular , Infecções por Coronavirus/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Células HEK293 , Ensaios de Triagem em Larga Escala/métodos , Humanos , Imunidade Humoral/imunologia , Fragmentos Fc das Imunoglobulinas/genética , Camundongos , Camundongos Endogâmicos BALB C , Testes de Neutralização , Peptidil Dipeptidase A/genética , Domínios Proteicos/imunologia , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Vacinas de Subunidades/imunologia
19.
Biol Direct ; 15(1): 19, 2020 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-33066821

RESUMO

The spike glycoprotein of the SARS-CoV-2 virus, which causes COVID-19, has attracted attention for its vaccine potential and binding capacity to host cell surface receptors. Much of this research focus has centered on the ectodomain of the spike protein. The ectodomain is anchored to a transmembrane region, followed by a cytoplasmic tail. Here we report a distant sequence similarity between the cysteine-rich cytoplasmic tail of the coronavirus spike protein and the hepcidin protein that is found in humans and other vertebrates. Hepcidin is thought to be the key regulator of iron metabolism in humans through its inhibition of the iron-exporting protein ferroportin. An implication of this preliminary observation is to suggest a potential route of investigation in the coronavirus research field making use of an already-established literature on the interplay of local and systemic iron regulation, cytokine-mediated inflammatory processes, respiratory infections and the hepcidin protein. The question of possible homology and an evolutionary connection between the viral spike protein and hepcidin is not assessed in this report, but some scenarios for its study are discussed.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/virologia , Hepcidinas/genética , Ferro/metabolismo , Pneumonia Viral/virologia , Glicoproteína da Espícula de Coronavírus/genética , Animais , Proteínas de Transporte de Cátions/metabolismo , Cisteína/química , Citocinas/metabolismo , Citoplasma/metabolismo , Hepcidinas/química , Humanos , Hipóxia , Inflamação , Interleucina-6/metabolismo , Pandemias , Domínios Proteicos , Processamento de Proteína Pós-Traducional , Alinhamento de Sequência , Glicoproteína da Espícula de Coronavírus/química , Tetraodontiformes
20.
Signal Transduct Target Ther ; 5(1): 220, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-33024075
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA