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1.
Front Med (Lausanne) ; 8: 772326, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34733870

RESUMO

Purpose: To assess the utility of non-contrast enhanced native T1 mapping of the renal cortex in assessing renal fibrosis for patients with chronic glomerulonephritis (CGN). Methods: A total of 119 patients with CGN and 19 healthy volunteers (HVs) were recruited for this study. Among these patients, 43 had undergone kidney biopsy measurements. Clinical information and biopsy pathological scores were collected. According to the results of the renal biopsy, the patients were classified into the high (25-50%), low (<25%) and no renal interstitial fibrosis (IF) (0%) groups. The correlations between the T1 value in the renal cortex and each of the clinical parameters were separately analyzed. The relationships between each fibrosis group and the T1 value were also evaluated and compared between groups. Binary logistic regression analysis was further used to determine the relationship between the T1 value and renal fibrosis. Receiver operating characteristic (ROC) curves were plotted to analyze the diagnostic value of the T1 value for renal fibrosis. Results: Compared with those of the HVs, the T1 values were significantly higher in patients at all stages of chronic kidney disease (CKD) (all p < 0.05). Significant T1 differences were also revealed between patients with different stages of CKD (p < 0.05). Additionally, the T1 value correlated well with CKD stage (p < 0.05), except between CKD 2 and 3. In addition, the T1 value was positively correlated with cystatin C, neutrophil gelatinase-associated lipocalin, and serum creatinine and negatively correlated with hemoglobin, kidney length, estimated glomerular filtration rate and hematocrit (all p < 0.05). Compared with those of the no IF group, the T1 values were increased in the low- and high-IF groups (both p < 0.05). Logistic regression analysis showed that an elevated T1 value was an independent risk factor for renal fibrosis. ROC analysis suggested that the optimal critical value of T1 for predicting renal fibrosis was 1,695 ms, with a specificity of 0.778 and a sensitivity of 0.625. Conclusion: Native T1 mapping demonstrated good diagnostic performance in evaluating renal function and was an effective noninvasive method for detecting renal fibrosis in CGN patients.

2.
PLoS Pathog ; 17(11): e1010053, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34748603

RESUMO

COVID-19 patients transmitted SARS-CoV-2 to minks in the Netherlands in April 2020. Subsequently, the mink-associated virus (miSARS-CoV-2) spilled back over into humans. Genetic sequences of the miSARS-CoV-2 identified a new genetic variant known as "Cluster 5" that contained mutations in the spike protein. However, the functional properties of these "Cluster 5" mutations have not been well established. In this study, we found that the Y453F mutation located in the RBD domain of miSARS-CoV-2 is an adaptive mutation that enhances binding to mink ACE2 and other orthologs of Mustela species without compromising, and even enhancing, its ability to utilize human ACE2 as a receptor for entry. Structural analysis suggested that despite the similarity in the overall binding mode of SARS-CoV-2 RBD to human and mink ACE2, Y34 of mink ACE2 was better suited to interact with a Phe rather than a Tyr at position 453 of the viral RBD due to less steric clash and tighter hydrophobic-driven interaction. Additionally, the Y453F spike exhibited resistance to convalescent serum, posing a risk for vaccine development. Thus, our study suggests that since the initial transmission from humans, SARS-CoV-2 evolved to adapt to the mink host, leading to widespread circulation among minks while still retaining its ability to efficiently utilize human ACE2 for entry, thus allowing for transmission of the miSARS-CoV-2 back into humans. These findings underscore the importance of active surveillance of SARS-CoV-2 evolution in Mustela species and other susceptible hosts in order to prevent future outbreaks.

3.
Nat Commun ; 12(1): 6624, 2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34785638

RESUMO

Epstein-Barr virus (EBV) is associated with a range of epithelial and B cell malignancies as well as autoimmune disorders, for which there are still no specific treatments or effective vaccines. Here, we isolate EBV gH/gL-specific antibodies from an EBV-infected individual. One antibody, 1D8, efficiently neutralizes EBV infection of two major target cell types, B cells and epithelial cells. In humanized mice, 1D8 provides protection against a high-dose EBV challenge by substantially reducing viral loads and associated tumor burden. Crystal structure analysis reveals that 1D8 binds to a key vulnerable interface between the D-I/D-II domains of the viral gH/gL protein, especially the D-II of the gH, thereby interfering with the gH/gL-mediated membrane fusion and binding to target cells. Overall, we identify a potent and protective neutralizing antibody capable of reducing the EBV load. The novel vulnerable site represents an attractive target that is potentially important for antibody and vaccine intervention against EBV infection.

4.
J Chromatogr A ; 1659: 462589, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34749183

RESUMO

An integrated QuEChERS strategy was developed by combining the extraction and purification processes into a single step. All of the pretreatment procedures could be performed in one tube within 5 min with the aid of magnetic nanoparticles and careful optimization of the key parameters, including the dosages of the sorbents (magnetic nanoparticles, C18, and graphitized carbon black), dehydrating and salting out reagents. The optimal method was validated and compared with the conventional QuEChERS method, demonstrating its clear superiority in terms of operating procedure, sample pretreatment time, and reagent dosages while affording equivalent pesticide recoveries and matrix effects. Further application of this method was performed to analyze 127 pesticide residues in solanaceous vegetables (tomato, pepper, and eggplant), leafy vegetables (brassica campestris and cabbage), legumes (green beans and cowpea), melon-type vegetables (cucumber and towel gourd), and a root vegetable (water bamboo), with the mean recoveries of the pesticides in the individual vegetable samples ranging from 70.6 to 92.8%. The method LOQs for these pesticides ranged from 10 to 50 µg/kg depending on the matrix. These results fully confirmed its wide applicability and versatility for achieving robust, rapid, and high-throughput multi-pesticide residues analysis in vegetable samples. More importantly, the developed strategy provides a greener and more "QuEChERS" design concept, which could be applied to the analysis of numerous types of pesticide residues in various matrices.

5.
J Virol ; : JVI0149221, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34668773

RESUMO

The COVID-19 pandemic, caused by SARS-CoV-2, has resulted in more than 235 million cases worldwide and 4.8 million deaths (October 2021), with varying incidences and mortalities among regions/ethnicities. The coronaviruses SARS-CoV, SARS-CoV-2 and HCoV-NL63 utilize the angiotensin-converting enzyme 2 (ACE2) as the receptor to enter cells. We hypothesized that the genetic variability in ACE2 may contribute to the variable clinical outcomes of COVID-19. To test this hypothesis, we first conducted an in silico investigation of single-nucleotide polymorphisms (SNPs) in the coding region of ACE2. We then applied an integrated approach of genetics, biochemistry and virology to explore the capacity of select ACE2 variants to bind coronavirus spike proteins and mediate viral entry. We identified the ACE2 D355N variant that restricts the spike protein-ACE2 interaction and consequently limits infection both in vitro and in vivo. In conclusion, ACE2 polymorphisms could modulate susceptibility to SARS-CoV-2, which may lead to variable disease severity. IMPORTANCE There is considerable variation in disease severity among patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes coronavirus disease 2019 (COVID-19). Human genetic variation can affect disease outcome, and the coronaviruses SARS-CoV, SARS-CoV-2 and HCoV-NL63 utilize human angiotensin-converting enzyme 2 (ACE2) as the receptor to enter cells. We found that several missense ACE2 SNVs that showed significantly altered binding with the spike proteins of SARS-CoV, SARS-CoV-2 and NL63-HCoV. We identified an ACE2 SNP D355N that restricts the spike protein-ACE2 interaction and consequently have the potential to protect individuals against SARS-CoV-2 infection. Our study highlights ACE2 polymorphisms could impact human susceptibility to SARS-CoV-2, which may contribute to ethnic and geographical differences in SARS-CoV-2 spread and pathogenicity.

6.
Nat Commun ; 12(1): 5654, 2021 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-34580297

RESUMO

There is an urgent need for animal models to study SARS-CoV-2 pathogenicity. Here, we generate and characterize a novel mouse-adapted SARS-CoV-2 strain, MASCp36, that causes severe respiratory symptoms, and mortality. Our model exhibits age- and gender-related mortality akin to severe COVID-19. Deep sequencing identified three amino acid substitutions, N501Y, Q493H, and K417N, at the receptor binding domain (RBD) of MASCp36, during in vivo passaging. All three RBD mutations significantly enhance binding affinity to its endogenous receptor, ACE2. Cryo-electron microscopy analysis of human ACE2 (hACE2), or mouse ACE2 (mACE2), in complex with the RBD of MASCp36, at 3.1 to 3.7 Å resolution, reveals the molecular basis for the receptor-binding switch. N501Y and Q493H enhance the binding affinity to hACE2, whereas triple mutations at N501Y/Q493H/K417N decrease affinity and reduce infectivity of MASCp36. Our study provides a platform for studying SARS-CoV-2 pathogenesis, and unveils the molecular mechanism for its rapid adaptation and evolution.


Assuntos
COVID-19/diagnóstico , SARS-CoV-2/patogenicidade , Glicoproteína da Espícula de Coronavírus/metabolismo , Substituição de Aminoácidos , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , Sítios de Ligação/genética , COVID-19/mortalidade , COVID-19/virologia , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Camundongos , Ligação Proteica/genética , Domínios Proteicos/genética , SARS-CoV-2/genética , Índice de Gravidade de Doença , Glicoproteína da Espícula de Coronavírus/genética
7.
Ecotoxicol Environ Saf ; 222: 112534, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34311429

RESUMO

Penflufen fungicide is widely used as a racemate, which has potential ecological risks to aquatic organisms, while its enantioselective toxicity data is limited. This study aimed to differentiate the enantioselective toxicity difference of penflufen enantiomers, and illuminate the enantioselective mechanism from the insight of enantiomer-protein specific binding. The semipreparative separation and absolute configuration of penflufen enantiomers were conducted. The acute toxicity of S-(+)-penflufen was 54 times higher than R-(-)-penflufen to Danio rerio, and the coexistence of R-(-)-penflufen could increase the exposure risk of S-(+)-penflufen. For chronic toxicity, after low-dose long-term exposure, rac-penflufen and S-(+)-penflufen inducted more serious oxidative stress than R-(-)-penflufen in D. rerio, and inhibited the succinate dehydrogenase (SDH) activity significantly. For target phytopathogen, the toxicity difference of S-(+)-penflufen and R-(-)-penflufen was up to 148 times for Rhizoctonia solani. Based on the toxic unit analysis, the toxic interactions of antagonistic effect and concentration addition were found between penflufen enantiomers, indicating the coexistence of R-(-)-penflufen could increase overuse and environmental risks. Computational chemistry was used to illuminate the enantioselectivity mechanism, and the lower binding energy between the active site of SDH and S-(+)-penflufen contributed to the higher toxicity. The higher target toxicity might be due to the hydrophobic pocket of CybL in R. solani was more benefited to S-(+)-penflufen binding SDH than Botrytis cinerea. These results could be helpful for further understanding the potential risk of chiral penflufen in the environment, demonstrating the importance of understanding the enantioselective difference of chiral pesticides, and providing a new insight for analyzing the enantioselective mechanism.


Assuntos
Fungicidas Industriais , Anilidas , Botrytis , Química Computacional , Fungicidas Industriais/toxicidade , Rhizoctonia , Estereoisomerismo
8.
Nat Commun ; 12(1): 4210, 2021 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-34244522

RESUMO

Neutralizing antibodies (nAbs) to SARS-CoV-2 hold powerful potentials for clinical interventions against COVID-19 disease. However, their common genetic and biologic features remain elusive. Here we interrogate a total of 165 antibodies from eight COVID-19 patients, and find that potent nAbs from different patients have disproportionally high representation of IGHV3-53/3-66 usage, and therefore termed as public antibodies. Crystal structural comparison of these antibodies reveals they share similar angle of approach to RBD, overlap in buried surface and binding residues on RBD, and have substantial spatial clash with receptor angiotensin-converting enzyme-2 (ACE2) in binding to RBD. Site-directed mutagenesis confirms these common binding features although some minor differences are found. One representative antibody, P5A-3C8, demonstrates extraordinarily protective efficacy in a golden Syrian hamster model against SARS-CoV-2 infection. However, virus escape analysis identifies a single natural mutation in RBD, namely K417N found in B.1.351 variant from South Africa, abolished the neutralizing activity of these public antibodies. The discovery of public antibodies and shared escape mutation highlight the intricate relationship between antibody response and SARS-CoV-2, and provide critical reference for the development of antibody and vaccine strategies to overcome the antigenic variation of SARS-CoV-2.


Assuntos
Enzima de Conversão de Angiotensina 2/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Receptores Virais/imunologia , SARS-CoV-2/imunologia , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , Sítios de Ligação/imunologia , COVID-19/imunologia , Cricetinae , Modelos Animais de Doenças , Epitopos/imunologia , Feminino , Humanos , Masculino , Testes de Neutralização , Receptores de Antígenos de Linfócitos B/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia
9.
Immunity ; 54(7): 1611-1621.e5, 2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34166623

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants continue to emerge during the global pandemic and may facilitate escape from current antibody therapies and vaccine protection. Here we showed that the South African variant B.1.351 was the most resistant to current monoclonal antibodies and convalescent plasma from coronavirus disease 2019 (COVID-19)-infected individuals, followed by the Brazilian variant P.1 and the United Kingdom variant B.1.1.7. This resistance hierarchy corresponded with Y144del and 242-244del mutations in the N-terminal domain and K417N/T, E484K, and N501Y mutations in the receptor-binding domain (RBD) of SARS-CoV-2. Crystal structure analysis of the B.1.351 triple mutant (417N-484K-501Y) RBD complexed with the monoclonal antibody P2C-1F11 revealed the molecular basis for antibody neutralization and escape. B.1.351 and P.1 also acquired the ability to use mouse and mink ACE2 receptors for entry. Our results demonstrate major antigenic shifts and potential broadening of the host range for B.1.351 and P.1 variants, which poses serious challenges to current antibody therapies and vaccine protection.


Assuntos
Enzima de Conversão de Angiotensina 2/metabolismo , Anticorpos Neutralizantes/imunologia , Evasão da Resposta Imune , SARS-CoV-2/imunologia , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/química , Variação Antigênica/genética , COVID-19/imunologia , COVID-19/virologia , Especificidade de Hospedeiro , Humanos , Evasão da Resposta Imune/genética , Camundongos , Vison , Mutação , Ligação Proteica , SARS-CoV-2/genética , SARS-CoV-2/fisiologia , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Internalização do Vírus
10.
Water Res ; 200: 117243, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34029872

RESUMO

The outbreak of coronavirus infectious disease-2019 (COVID-19) pneumonia challenges the rapid interrogation of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in human and environmental samples. In this study, we developed an assay using surface enhanced Raman scattering (SERS) coupled with multivariate analysis to detect SARS-CoV-2 in an ultra-fast manner without any pretreatment (e.g., RNA extraction). Using silver-nanorod SERS array functionalized with cellular receptor angiotensin-converting enzyme 2 (ACE2), we obtained strong SERS signals of ACE2 at 1032, 1051, 1089, 1189, 1447 and 1527 cm-1. The recognition and binding of receptor binding domain (RBD) of SARS-CoV-2 spike protein on SERS assay significantly quenched the spectral intensities of most peaks and exhibited a shift from 1189 to 1182 cm-1. On-site tests on 23 water samples with a portable Raman spectrometer proved its accuracy and easy-operation for spot detection of SARS-CoV-2 to evaluate disinfection performance, explore viral survival in environmental media, assess viral decay in wastewater treatment plant and track SARS-CoV-2 in pipe network. Our findings raise a state-of-the-art spectroscopic tool to screen and interrogate viruses with RBD for human cell entry, proving its feasibility and potential as an ultra-fast detection tool for wastewater-based epidemiology.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Domínios Proteicos , Análise Espectral Raman , Glicoproteína da Espícula de Coronavírus
11.
Environ Sci Technol ; 55(11): 7479-7490, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34002605

RESUMO

The increasing number of people with depression worldwide has led to concerns regarding antidepressant contamination in aquatic environments, which could have the risk of negative effects on aquatic organisms. Chirality increases its toxicity potentials. Accordingly, we investigated the negative effects of racemic (rac-), R-, and S-FX at environmental levels (100 ng/L) on the brain serotonergic system in zebrafish (Danio rerio) for 42 days. Additionally, we measured the whole-body concentrations of FX and norfluoxetine (NFX). We found that S-FX exposure disrupted the brain serotonergic system more severely than rac- and R-FX exposure. The mechanism underlying this disruption induced by S-FX was sex-specific, with female zebrafish showing disruption of the serotonin (5-HT) release process but male zebrafish showing disruption of the 5-HT synthesis process. In addition, enantioselective enrichment and biotransformation (R-FX to R-NFX and S-FX to S-NFX) occurred in zebrafish. Sex-specific accumulation was also observed, with higher concentrations in females. Our study provides evidence for enantiomer- and sex-specific effects of FX exposure at biologically relevant concentrations. More broadly, our study demonstrated that SSRI antidepressants, such as FX, can affect aquatic life by causing important shifts in not only their active sites of the serotonin transporter.


Assuntos
Fluoxetina , Poluentes Químicos da Água , Animais , Encéfalo , Feminino , Fluoxetina/toxicidade , Masculino , Inibidores de Captação de Serotonina/toxicidade , Estereoisomerismo , Poluentes Químicos da Água/toxicidade , Peixe-Zebra
12.
Cell Rep ; 35(5): 109070, 2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33951441

RESUMO

Four potent native human monoclonal antibodies (mAbs) targeting distinct epitopes on tetanus toxin (TeNT) are isolated with neutralization potency ranging from approximately 17 mg to 6 mg each that are equivalent to 250 IU of human anti-TeNT immunoglobulin. TT0170 binds fragment B, and TT0069 and TT0155 bind fragment AB. mAb TT0067 binds fragment C and blocks the binding of TeNT to gangliosides. The co-crystal structure of TT0067 with fragment C of TeNT at a 2.0-Å resolution demonstrates that mAb TT0067 directly occupies the W pocket of one of the receptor binding sites on TeNT, resulting in blocking the binding of TeNT to ganglioside on the surface of host cells. This study reveals at the atomic level the mechanism of action by the TeNT neutralizing antibody. The key neutralization epitope on the fragment C of TeNT identified in our work provides the critical information for the development of fragment C of TeNT as a better and safer tetanus vaccine.

13.
Crit Rev Food Sci Nutr ; : 1-18, 2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-33955294

RESUMO

Aflatoxins (AFs) contamination in food and agricultural products poses a significant threat to human health. Sensitive and accurate detection of AFs provides a strong guarantee for ensuring food safety. Conventional chromatographic-based or mass spectrum methods, which rely on bulky instrument and skilled personnel, are not suitable for on-site surveillance. By contrast, visual detections which possess the merits of rapidity and sophisticated instrument-free present an excellent potential for the on-site detection of AFs. This review intends to summarize the latest development of visual methods for AFs detection, including paper-based tests, chromogenic reactions, and luminescent methods. Emerging technologies, like nanotechnology, DNAzymes, and aptamers combined with these visual methods are introduced. The basic principles, features, and application advantages of each type of visual methods are discussed. The biggest challenges and perspectives on their future trends are also addressed.

14.
Int J Biol Macromol ; 181: 1023-1029, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-33894255

RESUMO

Vigna unguiculata subsp. sesquipedalis is an important derivative cultivar of cowpea planted widely in China, and popularly known as "Yard-long bean". There is lack of research about the structural characterization and physicochemical aspects of carbohydrate content in Yard-long bean seeds. Thus, the present study aimed to evaluate structures, thermal and technological properties of Yard-long bean seeds starch (YSS). The starch contains little of ash, protein and total fiber meanwhile amylose content of 37.52%. The shapes of the starch granules obtained from field emission scanning electron microscopy (FESEM) were oval to semi-elliptical with little granules occurring in agglomerated structures clusters, and volume median diameter of granules ranged from 10.5 µm to 12.5 µm. The initial gelatinization temperature of YSS was 73.86 °C, peak temperature was 80.59 °C and final 88.53 °C. Solubility index (SI, 3.43% at 90 °C) and swelling power (SP, 6.62 g/g at 90 °C) were observed with low volume, which corroborated with the C-type structure shown by X-ray diffraction (XRD) and high crystallinity degree. The extraction of YSS can be feasible, and it has suitable properties for use in the food industry.


Assuntos
Amilose/química , Fibras na Dieta , Amido/química , Vigna/química , China , Sementes/química , Solubilidade , Amido/isolamento & purificação , Temperatura , Difração de Raios X
15.
Immunity ; 54(4): 673-686.e4, 2021 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-33852831

RESUMO

The interleukin (IL)-17 family, consisting of six members, promotes host defense but can in some context promote the development of autoimmune disease. Here, we examined the role of IL-17D, a poorly understood member in the IL-17 family. IL-17D was expressed primarily by colonic epithelial cells. Il17d-/- mice were more susceptible to acute colitis, bacterial infection and experimentally induced colon cancer than their wildtype counterparts. Il17d deficiency impaired IL-22 production by group 3 innate lymphoid cells (ILC3s) and reduced expression of IL-22-dependent antimicrobial peptides, RegIIIß and RegIIIγ, in colon tissue at steady state and in colitis; this was associated with changes in microbial composition and dysbiosis. Protein purification studies revealed that IL-17D bound not canonical IL-17 receptors, but rather CD93, a glycoprotein expressed on mature ILC3s. Mice lacking Cd93 in ILC3s exhibited impaired IL-22 production and aggravated colonic inflammation in experimental colitis. Thus, an IL-17D-CD93 axis regulates ILC3 function to preserve intestinal homeostasis.


Assuntos
Imunidade Inata/imunologia , Interleucina-27/imunologia , Linfócitos/imunologia , Glicoproteínas de Membrana/imunologia , Animais , Linhagem Celular , Colite/imunologia , Colo/imunologia , Células Epiteliais/imunologia , Interleucinas/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células RAW 264.7
16.
Nat Commun ; 12(1): 1607, 2021 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-33707453

RESUMO

In recognizing the host cellular receptor and mediating fusion of virus and cell membranes, the spike (S) glycoprotein of coronaviruses is the most critical viral protein for cross-species transmission and infection. Here we determined the cryo-EM structures of the spikes from bat (RaTG13) and pangolin (PCoV_GX) coronaviruses, which are closely related to SARS-CoV-2. All three receptor-binding domains (RBDs) of these two spike trimers are in the "down" conformation, indicating they are more prone to adopt the receptor-binding inactive state. However, we found that the PCoV_GX, but not the RaTG13, spike is comparable to the SARS-CoV-2 spike in binding the human ACE2 receptor and supporting pseudovirus cell entry. We further identified critical residues in the RBD underlying different activities of the RaTG13 and PCoV_GX/SARS-CoV-2 spikes. These results collectively indicate that tight RBD-ACE2 binding and efficient RBD conformational sampling are required for the evolution of SARS-CoV-2 to gain highly efficient infection.


Assuntos
COVID-19/virologia , Quirópteros/virologia , Coronavirus/química , Coronavirus/genética , Pangolins/virologia , SARS-CoV-2/química , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Sequência de Aminoácidos , Enzima de Conversão de Angiotensina 2/química , Animais , COVID-19/epidemiologia , COVID-19/transmissão , Microscopia Crioeletrônica , Evolução Molecular , Interações entre Hospedeiro e Microrganismos , Humanos , Modelos Moleculares , Pandemias , Domínios Proteicos , Homologia de Sequência de Aminoácidos , Especificidade da Espécie , Glicoproteína da Espícula de Coronavírus/ultraestrutura
17.
Proc Natl Acad Sci U S A ; 118(12)2021 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-33658332

RESUMO

The pandemic of COVID-19, caused by SARS-CoV-2, is a major global health threat. Epidemiological studies suggest that bats (Rhinolophus affinis) are the natural zoonotic reservoir for SARS-CoV-2. However, the host range of SARS-CoV-2 and intermediate hosts that facilitate its transmission to humans remain unknown. The interaction of coronavirus with its host receptor is a key genetic determinant of host range and cross-species transmission. SARS-CoV-2 uses angiotensin-converting enzyme 2 (ACE2) as the receptor to enter host cells in a species-dependent manner. In this study, we characterized the ability of ACE2 from diverse species to support viral entry. By analyzing the conservation of five residues in two virus-binding hotspots of ACE2 (hotspot 31Lys and hotspot 353Lys), we predicted 80 ACE2 proteins from mammals that could potentially mediate SARS-CoV-2 entry. We chose 48 ACE2 orthologs among them for functional analysis, and showed that 44 of these orthologs-including domestic animals, pets, livestock, and animals commonly found in zoos and aquaria-could bind the SARS-CoV-2 spike protein and support viral entry. In contrast, New World monkey ACE2 orthologs could not bind the SARS-CoV-2 spike protein and support viral entry. We further identified the genetic determinant of New World monkey ACE2 that restricts viral entry using genetic and functional analyses. These findings highlight a potentially broad host tropism of SARS-CoV-2 and suggest that SARS-CoV-2 might be distributed much more widely than previously recognized, underscoring the necessity to monitor susceptible hosts to prevent future outbreaks.


Assuntos
Enzima de Conversão de Angiotensina 2/genética , COVID-19/veterinária , Receptores Virais/genética , SARS-CoV-2/genética , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , COVID-19/genética , COVID-19/metabolismo , COVID-19/virologia , Especificidade de Hospedeiro , Humanos , Pandemias/prevenção & controle , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/metabolismo , Filogenia , Ligação Proteica , Receptores Virais/metabolismo , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Tropismo Viral , Zoonoses Virais/genética , Zoonoses Virais/prevenção & controle , Zoonoses Virais/virologia , Ligação Viral , Internalização do Vírus
18.
PLoS Pathog ; 17(3): e1009392, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33760889

RESUMO

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.


Assuntos
COVID-19/enzimologia , COVID-19/genética , Peptidil Dipeptidase A/genética , Receptores Virais/genética , SARS-CoV-2/fisiologia , Animais , Sequência de Bases , COVID-19/virologia , Especificidade de Hospedeiro , Humanos , Camundongos/genética , Camundongos/virologia , Peptidil Dipeptidase A/química , Peptidil Dipeptidase A/metabolismo , Phascolarctidae/genética , Phascolarctidae/virologia , Receptores Virais/metabolismo , SARS-CoV-2/genética , Alinhamento de Sequência , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Internalização do Vírus
19.
Food Chem ; 354: 129502, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-33752118

RESUMO

The dissipation behaviors and exposure risks of individual and joint application of procymidone and carbendazim in greenhouse strawberries were studied. The initial concentrations were similar after individual or joint applications, while the dissipation half-lives and finial concentrations were significantly different. After joint application, the dissipation half-lives of procymidone and carbendazim were 12.9 and 16.0 days, respectively, which were about 1.8 times higher than those after individual application. Furthermore, the final residues under joint application condition were 1.8-3.5 times higher than those under individual application condition. The joint application decreased the dissipation rates of procymidone or carbendazim in strawberries, and increased the final residue concentrations. The dietary intake risks of procymidone and carbendazim (whether applied individually or jointly) were no higher than 0.12, which were acceptable for human health. This work would shed a light for the guidance of the joint application and risk assessment of the typical fungicides in strawberry.


Assuntos
Benzimidazóis/metabolismo , Compostos Bicíclicos com Pontes/metabolismo , Carbamatos/metabolismo , Fragaria/química , Benzimidazóis/análise , Compostos Bicíclicos com Pontes/análise , Carbamatos/análise , Cromatografia Líquida de Alta Pressão , Fragaria/metabolismo , Efeito Estufa , Meia-Vida , Humanos , Resíduos de Praguicidas/análise , Medição de Risco , Espectrometria de Massas por Ionização por Electrospray
20.
Cell Res ; 31(5): 517-525, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33731853

RESUMO

Neutralizing monoclonal antibodies (nAbs) to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) represent promising candidates for clinical intervention against coronavirus disease 2019 (COVID-19). We isolated a large number of nAbs from SARS-CoV-2-infected individuals capable of disrupting proper interaction between the receptor binding domain (RBD) of the viral spike (S) protein and the receptor angiotensin converting enzyme 2 (ACE2). However, the structural basis for their potent neutralizing activity remains unclear. Here, we report cryo-EM structures of the ten most potent nAbs in their native full-length IgG-form or in both IgG-form and Fab-form bound to the trimeric S protein of SARS-CoV-2. The bivalent binding of the full-length IgG is found to associate with more RBDs in the "up" conformation than the monovalent binding of Fab, perhaps contributing to the enhanced neutralizing activity of IgG and triggering more shedding of the S1 subunit from the S protein. Comparison of a large number of nAbs identified common and unique structural features associated with their potent neutralizing activities. This work provides a structural basis for further understanding the mechanism of nAbs, especially through revealing the bivalent binding and its correlation with more potent neutralization and the shedding of S1 subunit.


Assuntos
Anticorpos Neutralizantes/imunologia , COVID-19/imunologia , Imunoglobulina G/imunologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Enzima de Conversão de Angiotensina 2/imunologia , Anticorpos Neutralizantes/química , Anticorpos Neutralizantes/ultraestrutura , Anticorpos Antivirais/química , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/ultraestrutura , Interações Hospedeiro-Patógeno , Humanos , Imunoglobulina G/química , Imunoglobulina G/ultraestrutura , Modelos Moleculares , Conformação Proteica , Multimerização Proteica , SARS-CoV-2/fisiologia , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/ultraestrutura
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