Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 647
Filtrar
1.
Front Cell Infect Microbiol ; 11: 598875, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33791232

RESUMEN

In the last year, the advent of the COVID-19 pandemic brought a new consideration for the multidisciplinary sciences. The unknown mechanisms of infection used by SARS-CoV-2 and the absence of effective antiviral pharmacological therapy, diagnosis methods, and vaccines evoked scientific efforts on the COVID-19 outcome. In general, COVID-19 clinical features are a result of local and systemic inflammatory processes that are enhanced by some preexistent comorbidities, such as diabetes, obesity, cardiovascular, and pulmonary diseases, and biological factors, like gender and age. However, the discrepancies in COVID-19 clinical signs observed among those patients lead to investigations about the critical factors that deeply influence disease severity and death. Herein, we present the viral infection mechanisms and its consequences after blocking the angiotensin-converting enzyme 2 (ACE2) axis in different tissues and the progression of inflammatory and immunological reactions, especially the influence of genetic features on those differential clinical responses. Furthermore, we discuss the role of genotype as an essential indicator of COVID-19 susceptibility, considering the expression profiles, polymorphisms, gene identification, and epigenetic modifications of viral entry factors and their recognition, as well as the infection effects on cell signaling molecule expression, which amplifies disease severity.


Asunto(s)
/metabolismo , Sistema Renina-Angiotensina/fisiología , Glicoproteína de la Espiga del Coronavirus/metabolismo , /genética , Antivirales/farmacología , Citocinas/sangre , Citocinas/inmunología , Humanos , Factores de Riesgo , Glicoproteína de la Espiga del Coronavirus/genética
2.
Int J Med Mushrooms ; 23(3): 1-14, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33822495

RESUMEN

The most challenging threat facing the global community today is the coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Despite global efforts to develop suitable treatments, very few specific antiviral agents have been suggested and the virus remains a serious global health risk. In vivo animal experiments have demonstrated that bioactive mycochemical constituents of Inonotus obliquus have immunomodulatory, antimicrobial, and antiviral properties. The present study investigates the antiviral potential of I. obliquus terpenoids against COVID-19 using a molecular docking study. The in silico study elucidates the ability of most of the terpenoid components to interact with the receptor-binding domain of SARS-CoV-2 spike glycoprotein with excellent affinity. Additionally, we found that both betulinic acid and inonotusane C could bind and stably interact with the spike protein near the host cell recognition site of angiotensin-converting enzyme 2.


Asunto(s)
/tratamiento farmacológico , Simulación del Acoplamiento Molecular , Glicoproteína de la Espiga del Coronavirus/efectos de los fármacos , Terpenos/farmacología , Concentración 50 Inhibidora , Estructura Molecular , Glicoproteína de la Espiga del Coronavirus/metabolismo , Terpenos/química , Terpenos/metabolismo
3.
Molecules ; 26(6)2021 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-33806967

RESUMEN

Bats are unique in their potential to serve as reservoir hosts for intracellular pathogens. Recently, the impact of COVID-19 has relegated bats from biomedical darkness to the frontline of public health as bats are the natural reservoir of many viruses, including SARS-Cov-2. Many bat genomes have been sequenced recently, and sequences coding for antimicrobial peptides are available in the public databases. Here we provide a structural analysis of genome-predicted bat cathelicidins as components of their innate immunity. A total of 32 unique protein sequences were retrieved from the NCBI database. Interestingly, some bat species contained more than one cathelicidin. We examined the conserved cysteines within the cathelin-like domain and the peptide portion of each sequence and revealed phylogenetic relationships and structural dissimilarities. The antibacterial, antifungal, and antiviral activity of peptides was examined using bioinformatic tools. The peptides were modeled and subjected to docking analysis with the region binding domain (RBD) region of the SARS-CoV-2 Spike protein. The appearance of multiple forms of cathelicidins verifies the complex microbial challenges encountered by these species. Learning more about antiviral defenses of bats and how they drive virus evolution will help scientists to investigate the function of antimicrobial peptides in these species.


Asunto(s)
Catelicidinas/química , Catelicidinas/farmacología , Quirópteros/genética , Glicoproteína de la Espiga del Coronavirus/metabolismo , Animales , Antibacterianos/química , Antibacterianos/farmacología , Antifúngicos/química , Antifúngicos/farmacología , Péptidos Catiónicos Antimicrobianos/química , Péptidos Catiónicos Antimicrobianos/farmacología , Antivirales/química , Antivirales/farmacología , Sitios de Unión , Catelicidinas/genética , Catelicidinas/metabolismo , Biología Computacional/métodos , Simulación por Computador , Genoma , Simulación del Acoplamiento Molecular , Filogenia
4.
J Am Chem Soc ; 143(10): 3959-3966, 2021 03 17.
Artículo en Inglés | MEDLINE | ID: mdl-33657316

RESUMEN

The heterogeneity associated with glycosylation of the 66 N-glycan sites on the protein trimer making up the spike (S) region of the SARS-CoV-2 virus has been assessed by charge detection mass spectrometry (CDMS). CDMS allows simultaneous measurement of the mass-to-charge ratio and charge of individual ions, so that mass distributions can be determined for highly heterogeneous proteins such as the heavily glycosylated S protein trimer. The CDMS results are compared to recent glycoproteomics studies of the structure and abundance of glycans at specific sites. Interestingly, average glycan masses determined by "top-down" CDMS measurements are 35-47% larger than those obtained from the "bottom-up" glycoproteomics studies, suggesting that the glycoproteomic measurements underestimated the abundances of larger, more-complex glycans. Moreover, the distribution of glycan masses determined by CDMS is much broader than the distribution expected from the glycoproteomics studies, assuming that glycan processing on each trimer is not correlated. The breadth of the glycan mass distribution therefore indicates heterogeneity in the extent of glycan processing of the S protein trimers, with some trimers being much more heavily processed than others. This heterogeneity may have evolved as a way of further confounding the host's immune system.


Asunto(s)
Espectrometría de Masas , Polisacáridos/metabolismo , Multimerización de Proteína , Estructura Cuaternaria de Proteína , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/metabolismo , Células HEK293 , Humanos , Dominios Proteicos
6.
Biointerphases ; 16(1): 011006, 2021 01 28.
Artículo en Inglés | MEDLINE | ID: mdl-33706521

RESUMEN

The novel coronavirus caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has reached more than 160 countries and has been declared a pandemic. SARS-CoV-2 infects host cells by binding to the angiotensin-converting enzyme 2 (ACE-2) surface receptor via the spike (S) receptor-binding protein (RBD) on the virus envelope. Global data on a similar infectious disease spread by SARS-CoV-1 in 2002 indicated improved stability of the virus at lower temperatures facilitating its high transmission in the community during colder months (December-February). Seasonal viral transmissions are strongly modulated by temperatures, which can impact viral trafficking into host cells; however, an experimental study of temperature-dependent activity of SARS-CoV-2 is still lacking. We mimicked SARS-CoV-2 with polymer beads coated with the SARS-CoV-2 S protein to study the effect of seasonal temperatures on the binding of virus-mimicking nanospheres to lung epithelia. The presence of the S protein RBD on nanosphere surfaces led to binding by Calu-3 airway epithelial cells via the ACE-2 receptor. Calu-3 and control fibroblast cells with S-RBD-coated nanospheres were incubated at 33 and 37 °C to mimic temperature fluctuations in the host respiratory tract, and we found no temperature dependence in contrast to nonspecific binding of bovine serum ablumin-coated nanospheres. Moreover, the ambient temperature changes from 4 to 40 °C had no effect on S-RBD-ACE-2 ligand-receptor binding and minimal effect on the S-RBD protein structure (up to 40 °C), though protein denaturing occurred at 51 °C. Our results suggest that ambient temperatures from 4 to 40 °C have little effect on the SARS-CoV-2-ACE-2 interaction in agreement with the infection data currently reported.


Asunto(s)
/metabolismo , Materiales Biocompatibles Revestidos , Células Epiteliales/metabolismo , Pulmón/metabolismo , Nanosferas , Glicoproteína de la Espiga del Coronavirus , Temperatura , /metabolismo , Animales , Línea Celular Tumoral , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/metabolismo , Células Epiteliales/patología , Células Epiteliales/virología , Humanos , Pulmón/patología , Pulmón/virología , Ratones , Células 3T3 NIH , /metabolismo , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/metabolismo
7.
J Genet ; 1002021.
Artículo en Inglés | MEDLINE | ID: mdl-33707363

RESUMEN

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection is at present an emerging global public health crisis. Angiotensin converting enzyme 2 (ACE2) and trans-membrane protease serine 2 (TMPRSS2) are the two major host factors that contribute to the virulence of SARS-CoV-2 and pathogenesis of coronavirus disease-19 (COVID-19). Transmission of SARS-CoV-2 from animal to human is considered a rare event that necessarily requires strong evolutionary adaptations. Till date no other human cellular receptors are identified beside ACE2 for SARS-CoV-2 entry inside the human cell. Proteolytic cleavage of viral spike (S)-protein and ACE2 by TMPRSS2 began the entire host-pathogen interaction initiated with the physical binding of ACE2 to S-protein. SARS-CoV-2 S-protein binds to ACE2 with much higher affinity and stability than that of SARS-CoVs. Molecular interactions between ACE2-S and TMPRSS2-S are crucial and preciously mediated by specific residues. Structural stability, binding affinity and level of expression of these three interacting proteins are key susceptibility factors for COVID-19. Specific protein-protein interactions (PPI) are being identified that explains uniqueness of SARS-CoV-2 infection. Amino acid substitutions due to naturally occurring genetic polymorphisms potentially alter these PPIs and poses further clinical heterogeneity of COVID-19. Repurposing of several phytochemicals and approved drugs against ACE2, TMPRSS2 and S-protein have been proposed that could inhibit PPI between them. We have also identified some novel lead phytochemicals present in Azadirachta indica and Aloe barbadensis which could be utilized for further in vitro and in vivo anti-COVID-19 drug discovery. Uncovering details of ACE2-S and TMPRSS2-S interactions would further contribute to future research on COVID-19.


Asunto(s)
/metabolismo , /virología , Interacciones Huésped-Patógeno , Serina Endopeptidasas/metabolismo , /química , Animales , Antivirales/química , Antivirales/farmacología , Antivirales/uso terapéutico , /genética , Diseño de Fármacos , Predisposición Genética a la Enfermedad , Genoma Viral , Genómica/métodos , Humanos , Polimorfismo de Nucleótido Simple , Unión Proteica , Receptores Virales/metabolismo , Serina Endopeptidasas/química , Serina Endopeptidasas/genética , Glicoproteína de la Espiga del Coronavirus/metabolismo , Relación Estructura-Actividad , Internalización del Virus , Liberación del Virus , Replicación Viral
8.
FASEB J ; 35(4): e21384, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33710662

RESUMEN

Novel coronary pneumonia (COVID-19) is a respiratory distress syndrome caused by a new type of coronavirus. Understanding the genetic basis of susceptibility and prognosis to COVID-19 is of great significance to disease prevention, molecular typing, prognosis, and treatment. However, so far, there have been only two genome-wide association studies (GWASs) on the susceptibility of COVID-19. Starting with these reported DNA variants, we found the genes regulated by these variants through cis-eQTL and cis-meQTL acting. We further did a series of bioinformatics analysis on these potential risk genes. The analysis shows that the genetic variants on EHF regulate the expression of its neighbor CAT gene via cis-eQTL. There was significant evidence that CAT and the SARS-CoV-2-related S protein binding protein ACE2 interact with each other. Intracellular localization results showed that CAT and ACE2 proteins both exists in the cell membrane and extracellular area and their interaction could have an impact on the cell invasion ability of S protein. In addition, the expression of these three genes showed a significant positive correlation in the lungs. Based on these results, we propose that CAT plays a crucial intermediary role in binding effectiveness of ACE2, thereby affecting the susceptibility to COVID-19.


Asunto(s)
Catalasa , Regulación Enzimológica de la Expresión Génica , Predisposición Genética a la Enfermedad , Polimorfismo Genético , /metabolismo , /genética , /genética , Catalasa/biosíntesis , Catalasa/genética , Femenino , Estudio de Asociación del Genoma Completo , Humanos , Masculino , Estudios Retrospectivos , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
9.
Carbohydr Polym ; 260: 117797, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712145

RESUMEN

Severe acute respiratory syndrome-related coronavirus-2 (SARS-CoV-2) has resulted in a pandemic and continues to spread at an unprecedented rate around the world. Although a vaccine has recently been approved, there are currently few effective therapeutics to fight its associated disease in humans, COVID-19. SARS-CoV-2 and the related severe acute respiratory syndrome (SARS-CoV-1), and Middle East respiratory syndrome (MERS-CoV) result from zoonotic respiratory viruses that have bats as the primary host and an as yet unknown secondary host. While each of these viruses has different protein-based cell-surface receptors, each rely on the glycosaminoglycan, heparan sulfate as a co-receptor. In this study we compare, for the first time, differences and similarities in the structure of heparan sulfate in human and bat lungs. Furthermore, we show that the spike glycoprotein of COVID-19 binds 3.5 times stronger to human lung heparan sulfate than bat lung heparan sulfate.


Asunto(s)
Heparitina Sulfato/metabolismo , Pulmón/química , Receptores Virales/metabolismo , Glicoproteína de la Espiga del Coronavirus/metabolismo , Animales , Quirópteros , Femenino , Heparitina Sulfato/química , Heparitina Sulfato/aislamiento & purificación , Humanos , Masculino , Estructura Molecular , Peso Molecular , Unión Proteica , Receptores Virales/química , Receptores Virales/aislamiento & purificación
10.
Drug Des Devel Ther ; 15: 1111-1133, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33737804

RESUMEN

Purpose: SARS-CoV-2 engages human ACE2 through its spike (S) protein receptor binding domain (RBD) to enter the host cell. Recent computational studies have reported that withanone and withaferin A, phytochemicals found in Withania somnifera, target viral main protease (MPro) and host transmembrane TMPRSS2, and glucose related protein 78 (GRP78), respectively, implicating their potential as viral entry inhibitors. Absence of specific treatment against SARS-CoV-2 infection has encouraged exploration of phytochemicals as potential antivirals. Aim: This study aimed at in silico exploration, along with in vitro and in vivo validation of antiviral efficacy of the phytochemical withanone. Methods: Through molecular docking, molecular dynamic (MD) simulation and electrostatic energy calculation the plausible biochemical interactions between withanone and the ACE2-RBD complex were investigated. These in silico observations were biochemically validated by ELISA-based assays. Withanone-enriched extract from W. somnifera was tested for its ability to ameliorate clinically relevant pathological features, modelled in humanized zebrafish through SARS-CoV-2 recombinant spike (S) protein induction. Results: Withanone bound efficiently at the interacting interface of the ACE2-RBD complex and destabilized it energetically. The electrostatic component of binding free energies of the complex was significantly decreased. The two intrachain salt bridge interactions (K31-E35) and the interchain long-range ion-pair (K31-E484), at the ACE2-RBD interface were completely abolished by withanone, in the 50 ns simulation. In vitro binding assay experimentally validated that withanone efficiently inhibited (IC50=0.33 ng/mL) the interaction between ACE2 and RBD, in a dose-dependent manner. A withanone-enriched extract, without any co-extracted withaferin A, was prepared from W. somnifera leaves. This enriched extract was found to be efficient in ameliorating human-like pathological responses induced in humanized zebrafish by SARS-CoV-2 recombinant spike (S) protein. Conclusion: In conclusion, this study provided experimental validation for computational insight into the potential of withanone as a potent inhibitor of SARS-CoV-2 coronavirus entry into the host cells.


Asunto(s)
/metabolismo , Antivirales/farmacología , /efectos de los fármacos , Glicoproteína de la Espiga del Coronavirus/metabolismo , Withania , Witanólidos/farmacología , Células A549 , Animales , Antivirales/química , Antivirales/aislamiento & purificación , /virología , Modelos Animales de Enfermedad , Femenino , Interacciones Huésped-Patógeno , Humanos , Masculino , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Dominios y Motivos de Interacción de Proteínas , /patogenicidad , Glicoproteína de la Espiga del Coronavirus/química , Electricidad Estática , Relación Estructura-Actividad , Internalización del Virus/efectos de los fármacos , Withania/química , Witanólidos/química , Witanólidos/aislamiento & purificación , Pez Cebra
12.
mBio ; 12(2)2021 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-33653891

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a causative agent of the CoV disease 2019 (COVID-19) pandemic, enters host cells via the interaction of its receptor-binding domain (RBD) of the spike protein with host angiotensin-converting enzyme 2 (ACE2). Therefore, the RBD is a promising vaccine target to induce protective immunity against SARS-CoV-2 infection. In this study, we report the development of an RBD protein-based vaccine candidate against SARS-CoV-2 using self-assembling Helicobacter pylori-bullfrog ferritin nanoparticles as an antigen delivery system. RBD-ferritin protein purified from mammalian cells efficiently assembled into 24-mer nanoparticles. Sixteen- to 20-month-old ferrets were vaccinated with RBD-ferritin nanoparticles (RBD nanoparticles) by intramuscular or intranasal inoculation. All vaccinated ferrets with RBD nanoparticles produced potent neutralizing antibodies against SARS-CoV-2. Strikingly, vaccinated ferrets demonstrated efficient protection from SARS-CoV-2 challenge, showing no fever, body weight loss, or clinical symptoms. Furthermore, vaccinated ferrets showed rapid clearance of infectious virus in nasal washes and lungs as well as of viral RNA in respiratory organs. This study demonstrates that spike RBD-nanoparticles are an effective protein vaccine candidate against SARS-CoV-2.


Asunto(s)
/prevención & control , Nanopartículas/química , Glicoproteína de la Espiga del Coronavirus/metabolismo , Vacunas Virales/uso terapéutico , /química , Animales , Celulosa/química , Coronavirus/inmunología , Coronavirus/patogenicidad , Hurones , Ferritinas , Vacunas Virales/química
13.
Biomolecules ; 11(2)2021 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-33671255

RESUMEN

SARS-CoV-2, or COVID-19, has a devastating effect on our society, both in terms of quality of life and death rates; hence, there is an urgent need for developing safe and effective therapeutics against SARS-CoV-2. The most promising strategy to fight against this deadly virus is to develop an effective vaccine. Internalization of SARS-CoV-2 into the human host cell mainly occurs through the binding of the coronavirus spike protein (a trimeric surface glycoprotein) to the human angiotensin-converting enzyme 2 (ACE2) receptor. The spike-ACE2 protein-protein interaction is mediated through the receptor-binding domain (RBD) of the spike protein. Mutations in the spike RBD can significantly alter interactions with the ACE2 host receptor. Due to its important role in virus transmission, the spike RBD is considered to be one of the key molecular targets for vaccine development. In this study, a spike RBD-based subunit vaccine was designed by utilizing a ferritin protein nanocage as a scaffold. Several fusion protein constructs were designed in silico by connecting the spike RBD via a synthetic linker (different sizes) to different ferritin subunits (H-ferritin and L-ferritin). The stability and the dynamics of the engineered nanocage constructs were tested by extensive molecular dynamics simulation (MDS). Based on our MDS analysis, a five amino acid-based short linker (S-Linker) was the most effective for displaying the spike RBD over the surface of ferritin. The behavior of the spike RBD binding regions from the designed chimeric nanocages with the ACE2 receptor was highlighted. These data propose an effective multivalent synthetic nanocage, which might form the basis for new vaccine therapeutics designed against viruses such as SARS-CoV-2.


Asunto(s)
/química , Ferritinas/química , Nanoestructuras/química , Glicoproteína de la Espiga del Coronavirus/química , /metabolismo , /metabolismo , Ferritinas/metabolismo , Humanos , Simulación de Dinámica Molecular , Conformación Proteica , Dominios Proteicos , Dominios y Motivos de Interacción de Proteínas , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/metabolismo , Glicoproteína de la Espiga del Coronavirus/metabolismo , Vacunas de Subunidad/química , Vacunas de Subunidad/metabolismo
14.
Front Immunol ; 12: 598778, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33717077

RESUMEN

Emerging infectious diseases (EIDs) caused by viruses are increasing in frequency, causing a high disease burden and mortality world-wide. The COVID-19 pandemic caused by the novel SARS-like coronavirus (SARS-CoV-2) underscores the need to innovate and accelerate the development of effective vaccination strategies against EIDs. Human leukocyte antigen (HLA) molecules play a central role in the immune system by determining the peptide repertoire displayed to the T-cell compartment. Genetic polymorphisms of the HLA system thus confer a strong variability in vaccine-induced immune responses and may complicate the selection of vaccine candidates, because the distribution and frequencies of HLA alleles are highly variable among different ethnic groups. Herein, we build on the emerging paradigm of rational epitope-based vaccine design, by describing an immunoinformatics tool (Predivac-3.0) for proteome-wide T-cell epitope discovery that accounts for ethnic-level variations in immune responsiveness. Predivac-3.0 implements both CD8+ and CD4+ T-cell epitope predictions based on HLA allele frequencies retrieved from the Allele Frequency Net Database. The tool was thoroughly assessed, proving comparable performances (AUC ~0.9) against four state-of-the-art pan-specific immunoinformatics methods capable of population-level analysis (NetMHCPan-4.0, Pickpocket, PSSMHCPan and SMM), as well as a strong accuracy on proteome-wide T-cell epitope predictions for HIV-specific immune responses in the Japanese population. The utility of the method was investigated for the COVID-19 pandemic, by performing in silico T-cell epitope mapping of the SARS-CoV-2 spike glycoprotein according to the ethnic context of the countries where the ChAdOx1 vaccine is currently initiating phase III clinical trials. Potentially immunodominant CD8+ and CD4+ T-cell epitopes and population coverages were predicted for each population (the Epitope Discovery mode), along with optimized sets of broadly recognized (promiscuous) T-cell epitopes maximizing coverage in the target populations (the Epitope Optimization mode). Population-specific epitope-rich regions (T-cell epitope clusters) were further predicted in protein antigens based on combined criteria of epitope density and population coverage. Overall, we conclude that Predivac-3.0 holds potential to contribute in the understanding of ethnic-level variations of vaccine-induced immune responsiveness and to guide the development of epitope-based next-generation vaccines against emerging pathogens, whose geographic distributions and populations in need of vaccinations are often well-defined for regional epidemics.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Epítopos de Linfocito T/metabolismo , Grupos Étnicos , Antígenos HLA/metabolismo , Proteómica/métodos , Glicoproteína de la Espiga del Coronavirus/metabolismo , /epidemiología , Enfermedades Transmisibles Emergentes , Epítopos de Linfocito T/genética , Antígenos HLA/genética , Humanos , Inmunogenicidad Vacunal , Aplicaciones de la Informática Médica , Pandemias/prevención & control , Polimorfismo Genético , Unión Proteica , Programas Informáticos , Glicoproteína de la Espiga del Coronavirus/genética
15.
Int J Mol Sci ; 22(5)2021 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-33668756

RESUMEN

Despite sequence similarity to SARS-CoV-1, SARS-CoV-2 has demonstrated greater widespread virulence and unique challenges to researchers aiming to study its pathogenicity in humans. The interaction of the viral receptor binding domain (RBD) with its main host cell receptor, angiotensin-converting enzyme 2 (ACE2), has emerged as a critical focal point for the development of anti-viral therapeutics and vaccines. In this study, we selectively identify and characterize the impact of mutating certain amino acid residues in the RBD of SARS-CoV-2 and in ACE2, by utilizing our recently developed NanoBiT technology-based biosensor as well as pseudotyped-virus infectivity assays. Specifically, we examine the mutational effects on RBD-ACE2 binding ability, efficacy of competitive inhibitors, as well as neutralizing antibody activity. We also look at the implications the mutations may have on virus transmissibility, host susceptibility, and the virus transmission path to humans. These critical determinants of virus-host interactions may provide more effective targets for ongoing vaccines, drug development, and potentially pave the way for determining the genetic variation underlying disease severity.


Asunto(s)
/química , /metabolismo , /metabolismo , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/metabolismo , Secuencia de Aminoácidos , Anticuerpos Neutralizantes/inmunología , Antivirales/farmacología , Sitios de Unión , /inmunología , Células HEK293 , Interacciones Microbiota-Huesped , Humanos , Modelos Moleculares , Mutación , Unión Proteica , Dominios y Motivos de Interacción de Proteínas , Receptores Virales/química , Receptores Virales/metabolismo , Alineación de Secuencia
16.
J Phys Chem B ; 125(10): 2533-2550, 2021 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-33657325

RESUMEN

The novel RNA virus, severe acute respiratory syndrome coronavirus II (SARS-CoV-2), is currently the leading cause of mortality in 2020, having led to over 1.6 million deaths and infecting over 75 million people worldwide by December 2020. While vaccination has started and several clinical trials for a number of vaccines are currently underway, there is a pressing need for a cure for those already infected with the virus. Of particular interest in the design of anti-SARS-CoV-2 therapeutics is the human protein angiotensin converting enzyme II (ACE2) to which this virus adheres before entry into the host cell. The SARS-CoV-2 virion binds to cell-surface bound ACE2 via interactions of the spike protein (s-protein) on the viral surface with ACE2. In this paper, we use all-atom molecular dynamics simulations and binding enthalpy calculations to determine the effect that a bound ACE2 active site inhibitor (MLN-4760) would have on the binding affinity of SARS-CoV-2 s-protein with ACE2. Our analysis indicates that the binding enthalpy could be reduced for s-protein adherence to the active site inhibitor-bound ACE2 protein by as much as 1.48-fold as an upper limit. This weakening of binding strength was observed to be due to the destabilization of the interactions between ACE2 residues Glu-35, Glu-37, Tyr-83, Lys-353, and Arg-393 and the SARS-CoV-2 s-protein receptor binding domain (RBD). The conformational changes were shown to lead to weakening of ACE2 interactions with SARS-CoV-2 s-protein, therefore reducing s-protein binding strength. Further, we observed increased conformational lability of the N-terminal helix and a conformational shift of a significant portion of the ACE2 motifs involved in s-protein binding, which may affect the kinetics of the s-protein binding when the small molecule inhibitor is bound to the ACE2 active site. These observations suggest potential new ways for interfering with the SARS-CoV-2 adhesion by modulating ACE2 conformation through distal active site inhibitor binding.


Asunto(s)
/metabolismo , Inhibidores de Proteasas/metabolismo , Glicoproteína de la Espiga del Coronavirus/metabolismo , /antagonistas & inhibidores , Sitios de Unión , /virología , Dominio Catalítico , Diseño de Fármacos , Humanos , Enlace de Hidrógeno , Simulación de Dinámica Molecular , Inhibidores de Proteasas/química , Unión Proteica , Dominios y Motivos de Interacción de Proteínas , Estructura Terciaria de Proteína , Bibliotecas de Moléculas Pequeñas/química , Bibliotecas de Moléculas Pequeñas/metabolismo , Glicoproteína de la Espiga del Coronavirus/química , Termodinámica
18.
PLoS Pathog ; 17(3): e1009392, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33760889

RESUMEN

Coronavirus interaction with its viral receptor is a primary genetic determinant of host range and tissue tropism. SARS-CoV-2 utilizes ACE2 as the receptor to enter host cell in a species-specific manner. We and others have previously shown that ACE2 orthologs from New World monkey, koala and mouse cannot interact with SARS-CoV-2 to mediate viral entry, and this defect can be restored by humanization of the restrictive residues in New World monkey ACE2. To better understand the genetic determinants behind the ability of ACE2 orthologs to support viral entry, we compared koala and mouse ACE2 sequences with that of human and identified the key residues in koala and mouse ACE2 that restrict viral receptor activity. Humanization of these critical residues rendered both koala and mouse ACE2 capable of binding the spike protein and facilitating viral entry. Our study shed more lights into the genetic determinants of ACE2 as the functional receptor of SARS-CoV-2, which facilitates our understanding of viral entry.


Asunto(s)
/enzimología , Peptidil-Dipeptidasa A/genética , Receptores Virales/genética , /fisiología , Animales , Secuencia de Bases , Especificidad del Huésped , Humanos , Ratones/genética , Ratones/virología , Peptidil-Dipeptidasa A/química , Peptidil-Dipeptidasa A/metabolismo , Phascolarctidae/genética , Phascolarctidae/virología , Receptores Virales/metabolismo , Alineación de Secuencia , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/metabolismo , Internalización del Virus
19.
Cell Rep ; 34(13): 108915, 2021 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-33761319

RESUMEN

To fully decipher the immunogenicity of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Spike protein, it is essential to assess which part is highly immunogenic in a systematic way. We generate a linear epitope landscape of the Spike protein by analyzing the serum immunoglobulin G (IgG) response of 1,051 coronavirus disease 2019 (COVID-19) patients with a peptide microarray. We reveal two regions rich in linear epitopes, i.e., C-terminal domain (CTD) and a region close to the S2' cleavage site and fusion peptide. Unexpectedly, we find that the receptor binding domain (RBD) lacks linear epitope. We reveal that the number of responsive peptides is highly variable among patients and correlates with disease severity. Some peptides are moderately associated with severity and clinical outcome. By immunizing mice, we obtain linear-epitope-specific antibodies; however, no significant neutralizing activity against the authentic virus is observed for these antibodies. This landscape will facilitate our understanding of SARS-CoV-2-specific humoral responses and might be useful for vaccine refinement.


Asunto(s)
/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Adulto , Animales , Anticuerpos Monoclonales/inmunología , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Antígenos Virales/inmunología , /genética , China/epidemiología , Modelos Animales de Enfermedad , Mapeo Epitopo/métodos , Epítopos/inmunología , Femenino , Humanos , Inmunoglobulina G/inmunología , Masculino , Ratones , Ratones Endogámicos BALB C , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/metabolismo
20.
Front Cell Infect Microbiol ; 11: 563085, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33643932

RESUMEN

In late December 2019, a vtiral pneumonia with an unknown agent was reported in Wuhan, China. A novel coronavirus was identified as the causative agent. Because of the human-to-human transmission and rapid spread; coronavirus disease 2019 (COVID-19) has rapidly increased to an epidemic scale and poses a severe threat to human health; it has been declared a public health emergency of international concern (PHEIC) by the World Health Organization (WHO). This review aims to summarize the recent research progress of COVID-19 molecular features and immunopathogenesis to provide a reference for further research in prevention and treatment of SARS coronavirus2 (SARS-CoV-2) infection based on the knowledge from researches on SARS-CoV and Middle East respiratory syndrome-related coronavirus (MERS-CoV).


Asunto(s)
/metabolismo , /patogenicidad , Inmunidad Adaptativa , /inmunología , Citocinas/inmunología , Citocinas/metabolismo , Humanos , Inmunidad Innata , /fisiología , Glicoproteína de la Espiga del Coronavirus/metabolismo , Internalización del Virus
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...