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1.
Nat Commun ; 11(1): 4687, 2020 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-32948771

RESUMO

Chemical biology strategies for directly perturbing protein homeostasis including the degradation tag (dTAG) system provide temporal advantages over genetic approaches and improved selectivity over small molecule inhibitors. We describe dTAGV-1, an exclusively selective VHL-recruiting dTAG molecule, to rapidly degrade FKBP12F36V-tagged proteins. dTAGV-1 overcomes a limitation of previously reported CRBN-recruiting dTAG molecules to degrade recalcitrant oncogenes, supports combination degrader studies and facilitates investigations of protein function in cells and mice.


Assuntos
Peptídeo Hidrolases/metabolismo , Proteínas/metabolismo , Proteína Supressora de Tumor Von Hippel-Lindau/metabolismo , Animais , Feminino , Técnicas de Inativação de Genes , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos Knockout , Modelos Animais , Proteômica , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteína 1A de Ligação a Tacrolimo/genética , Proteína 1A de Ligação a Tacrolimo/metabolismo , Proteínas de Ligação a Tacrolimo , Proteína Supressora de Tumor Von Hippel-Lindau/genética
2.
Nat Commun ; 11(1): 4393, 2020 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-32879321

RESUMO

Rcr3 is a secreted protease of tomato that is targeted by fungal effector Avr2, a secreted protease inhibitor of the fungal pathogen Cladosporium fulvum. The Avr2-Rcr3 complex is recognized by receptor-like protein Cf-2, triggering hypersensitive cell death (HR) and disease resistance. Avr2 also targets Rcr3 paralog Pip1, which is not required for Avr2 recognition but contributes to basal resistance. Thus, Rcr3 acts as a guarded decoy in this interaction, trapping the fungus into a recognition event. Here we show that Rcr3 evolved > 50 million years ago (Mya), whereas Cf-2 evolved <6Mya by co-opting the pre-existing Rcr3 in the Solanum genus. Ancient Rcr3 homologs present in tomato, potato, eggplants, pepper, petunia and tobacco can be inhibited by Avr2 with the exception of tobacco Rcr3. Four variant residues in Rcr3 promote Avr2 inhibition, but the Rcr3 that co-evolved with Cf-2 lacks three of these residues, indicating that the Rcr3 co-receptor is suboptimal for Avr2 binding. Pepper Rcr3 triggers HR with Cf-2 and Avr2 when engineered for enhanced inhibition by Avr2. Nicotiana benthamiana (Nb) is a natural null mutant carrying Rcr3 and Pip1 alleles with deleterious frame-shift mutations. Resurrected NbRcr3 and NbPip1 alleles were active proteases and further NbRcr3 engineering facilitated Avr2 inhibition, uncoupled from HR signalling. The evolution of a receptor co-opting a conserved pathogen target contrasts with other indirect pathogen recognition mechanisms.


Assuntos
Cladosporium , Resistência à Doença/genética , Peptídeo Hidrolases/genética , Imunidade Vegetal/genética , Solanum , Tabaco , Cladosporium/genética , Cladosporium/metabolismo , Cladosporium/patogenicidade , Evolução Molecular , Proteínas Fúngicas/metabolismo , Genes de Plantas , Interações Hospedeiro-Parasita , Peptídeo Hidrolases/metabolismo , Filogenia , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Inibidores de Proteases/metabolismo , Solanum/genética , Solanum/metabolismo , Solanum/microbiologia , Tabaco/genética , Tabaco/metabolismo , Tabaco/microbiologia
3.
Molecules ; 25(16)2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-32824454

RESUMO

A novel coronavirus (severe acute respiratory syndrome coronavirus 2, SARS-CoV-2) has been the cause of a recent global pandemic. The highly contagious nature of this life-threatening virus makes it imperative to find therapies to counteract its diffusion. The main protease (Mpro) of SARS-CoV-2 is a promising drug target due to its indispensable role in viral replication inside the host. Using a combined two-steps approach of virtual screening and molecular docking techniques, we have screened an in-house collection of small molecules, mainly composed of natural and nature-inspired compounds. The molecules were selected with high structural diversity to cover a wide range of chemical space into the enzyme pockets. Virtual screening experiments were performed using the blind docking mode of the AutoDock Vina software. Virtual screening allowed the selection of structurally heterogeneous compounds capable of interacting effectively with the enzymatic site of SARS-CoV-2 Mpro. The compounds showing the best interaction with the protein were re-scored by molecular docking as implemented in AutoDock, while the stability of the complexes was tested by molecular dynamics. The most promising candidates revealed a good ability to fit into the protein binding pocket and to reach the catalytic dyad. There is a high probability that at least one of the selected scaffolds could be promising for further research.


Assuntos
Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Produtos Biológicos/farmacologia , Infecções por Coronavirus/tratamento farmacológico , Pneumonia Viral/tratamento farmacológico , Inibidores de Proteases/farmacologia , Reposicionamento de Medicamentos , Humanos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Pandemias , Peptídeo Hidrolases/metabolismo , Proteínas da Matriz Viral/antagonistas & inibidores
4.
J Phys Chem Lett ; 11(17): 7267-7272, 2020 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-32787337

RESUMO

The coronavirus disease pandemic caused by infection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has affected the global healthcare system. As low-molecular-weight drugs have high potential to completely match interactions with essential SARS-CoV-2 targets, we propose a strategy to identify such drugs using the fragment-based approach. Herein, using ligand- and protein-observed fragment screening approaches, we identified niacin and hit 1 binding to the catalytic pocket of the main protease (Mpro) of SARS-CoV-2, thereby modestly inhibiting the enzymatic activity of Mpro. We further searched for low-molecular-weight drugs containing niacin or hit 1 pharmacophores with enhanced inhibiting activity, e.g., carmofur, bendamustine, triclabendazole, emedastine, and omeprazole, in which omeprazole is the only one binding to the C-terminal domain of SARS-CoV-2 Mpro. Our study demonstrates that the fragment-based approach is a feasible strategy for identifying low-molecular-weight drugs against the SARS-CoV-2 and other potential targets lacking specific drugs.


Assuntos
Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Reposicionamento de Medicamentos , Peptídeo Hidrolases/metabolismo , Relação Dose-Resposta a Droga , Modelos Moleculares , Peso Molecular , Peptídeo Hidrolases/química , Domínios Proteicos
5.
Proc Natl Acad Sci U S A ; 117(29): 17409-17417, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32616567

RESUMO

Proteolytic cascades regulate immunity and development in animals, but these cascades in plants have not yet been reported. Here we report that the extracellular immune protease Rcr3 of tomato is activated by P69B and other subtilases (SBTs), revealing a proteolytic cascade regulating extracellular immunity in solanaceous plants. Rcr3 is a secreted papain-like Cys protease (PLCP) of tomato that acts both in basal resistance against late blight disease (Phytophthora infestans) and in gene-for-gene resistance against the fungal pathogen Cladosporium fulvum (syn. Passalora fulva) Despite the prevalent model that Rcr3-like proteases can activate themselves at low pH, we found that catalytically inactive proRcr3 mutant precursors are still processed into mature mRcr3 isoforms. ProRcr3 is processed by secreted P69B and other Asp-selective SBTs in solanaceous plants, providing robust immunity through SBT redundancy. The apoplastic effector EPI1 of P. infestans can block Rcr3 activation by inhibiting SBTs, suggesting that this effector promotes virulence indirectly by preventing the activation of Rcr3(-like) immune proteases. Rcr3 activation in Nicotiana benthamiana requires a SBT from a different subfamily, indicating that extracellular proteolytic cascades have evolved convergently in solanaceous plants or are very ancient in the plant kingdom. The frequent incidence of Asp residues in the cleavage region of Rcr3-like proteases in solanaceous plants indicates that activation of immune proteases by SBTs is a general mechanism, illuminating a proteolytic cascade that provides robust apoplastic immunity.


Assuntos
Lycopersicon esculentum/metabolismo , Peptídeo Hidrolases/metabolismo , Doenças das Plantas/imunologia , Imunidade Vegetal , Proteólise , Cladosporium , Lycopersicon esculentum/genética , Peptídeo Hidrolases/genética , Phytophthora infestans , Doenças das Plantas/parasitologia , Doenças das Plantas/prevenção & controle , Proteínas de Plantas/metabolismo , Isoformas de Proteínas , Virulência
6.
Extremophiles ; 24(5): 693-704, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32617734

RESUMO

A new keratinase producer, Bacillus sp. BK111, isolated from a poultry feather was identified as Bacillus zhangzhouensis, which is the first report for its keratinolytic activity. The keratinase production was optimized, followed by the enzyme purification and characterization using biochemical assays. A 2.34-fold increase was observed in the enzyme production under optimized conditions. The enzyme was characterized as a serine protease with 42 kDa molecular weight, stable in a wide range of temperature and pH with maximum keratinolytic activity at 60 °C and pH 9.5. The enzyme had a wide range of different substrates with the best performance on the feather meal substrate. Metal ions of Ca2+, K+, Na+ and Mn2+ enhanced the enzyme activity. The enzyme showed a great deal of stability in the presence of ethanol, methanol, acetone, 2-propanol, dimethyl sulfoxide, Tween-80 and Triton X-100. Dithiothreitol (DTT), as a reducing agent, caused a twofold increase in keratinolytic activity. The half-life of the enzyme at optimum temperature was calculated to be 125 min and the ratio of keratinolytic:caseinolytic for the enzyme was 0.8. Our results showed the remarkable features of the enzyme that make it suitable for biotechnological usages.


Assuntos
Bacillus , Peptídeo Hidrolases , Animais , Bacillus/enzimologia , Concentração de Íons de Hidrogênio , Peptídeo Hidrolases/metabolismo , Especificidade por Substrato , Tensoativos , Temperatura
7.
Cardiovasc Res ; 116(10): 1733-1741, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32638018

RESUMO

AIMS: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) directly binds to ACE2 (angiotensin-converting enzyme 2) to facilitate cellular entry. Compared with the lung or respiratory tract, the human heart exhibits greater ACE2 expression. However, little substantial damage was found in the heart tissue, and no viral particles were observed in the cardiac myocytes. This study aims to analyse ACE2 and SARS-CoV-2 spike (S) protein proteases at the single-cell level, to explore the cardiac involvement in COVID-19 and improve our understanding of the potential cardiovascular implications of COVID-19. METHODS AND RESULTS: With meta-analysis, the prevalence of cardiac injury in COVID-19 patients varies from 2% [95% confidence interval (CI) 0-5%, I2 = 0%] in non-ICU patients to 59% (95% CI 48-71%, I2 = 85%) in non-survivors. With public single-cell sequence data analysis, ACE2 expression in the adult human heart is higher than that in the lung (adjusted P < 0.0001). Inversely, the most important S protein cleavage protease TMPRSS2 (transmembrane protease serine protease-2) in the heart exhibits an extremely lower expression than that in the lung (adjusted P < 0.0001), which may restrict entry of SARS-CoV-2 into cardiac cells. Furthermore, we discovered that other S protein proteases, CTSL (cathepsin L) and FURIN (furin, paired basic amino acid cleaving enzyme), were expressed in the adult heart at a similar level to that in the lung, which may compensate for TMPRSS2, mediating cardiac involvement in COVID-19. CONCLUSION: Compared with the lung, ACE2 is relatively more highly expressed in the human heart, while the key S protein priming protease, TMPRSS2, is rarely expressed. The low percentage of ACE2+/TMPRSS2+ cells reduced heart vulnerability to SARS-CoV-2 to some degree. CTSL and FURIN may compensate for S protein priming to mediate SARS-CoV-2 infection of the heart.


Assuntos
Betacoronavirus/patogenicidade , Infecções por Coronavirus/metabolismo , Miocárdio/enzimologia , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/metabolismo , Análise de Célula Única , Glicoproteína da Espícula de Coronavírus/metabolismo , Humanos , Pulmão/metabolismo , Pulmão/virologia , Pandemias , Peptídeo Hidrolases/metabolismo , Proteólise
8.
Food Chem ; 333: 127549, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32683266

RESUMO

Enzymatic tenderization is extensively applied in the meat industry, whereas its influence on meat flavor has seldom been evaluated. Proteinase K, papain, bromelain and Flavourzyme® were used to treat beef muscle, and the changes in volatile compounds and odors were subsequently analyzed. Proteolysis by proteinase K was found to elevate the average bitterness of the identified peptides by generating peptides with high Q values, whereas proteolysis by papain generated the highest level of amino acids. Enzymatic treatment by Flavourzyme and bromelain significantly elevated the levels of ketones and odors, whereas excessive proteolysis by papain and proteinase K largely reduced the levels of esters and aldehydes. The level of amino acids and degree of hydrolysis were found to be predominant factors that regulated the level of volatiles and odors. These results highlighted the huge influence of enzymatic tenderization on meat flavor, depending on degree of hydrolysis and cleavage pattern of applied proteases.


Assuntos
Proteínas Musculares/metabolismo , Odorantes , Peptídeo Hidrolases/metabolismo , Proteólise , Carne Vermelha/análise , Compostos Orgânicos Voláteis/metabolismo , Aminoácidos/metabolismo , Animais , Bovinos , Hidrólise , Paladar
9.
PLoS One ; 15(6): e0231681, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32555742

RESUMO

Eudiplozoon nipponicum (Goto, 1891) is a hematophagous monogenean ectoparasite which inhabits the gills of the common carp (Cyprinus carpio). Heavy infestation can lead to anemia and in conjunction with secondary bacterial infections cause poor health and eventual death of the host. This study is based on an innovative approach to protein localization which has never been used in parasitology before. Using laser capture microdissection, we dissected particular areas of the parasite body without contaminating the samples by surrounding tissue and in combination with analysis by mass spectrometry obtained tissue-specific proteomes of tegument, intestine, and parenchyma of our model organism, E. nipponicum. We successfully verified the presence of certain functional proteins (e.g. cathepsin L) in tissues where their presence was expected (intestine) and confirmed that there were no traces of these proteins in other tissues (tegument and parenchyma). Additionally, we identified a total of 2,059 proteins, including 72 peptidases and 33 peptidase inhibitors. As expected, the greatest variety was found in the intestine and the lowest variety in the parenchyma. Our results are significant on two levels. Firstly, we demonstrated that one can localize all proteins in one analysis and without using laboratory animals (antibodies for immunolocalization of single proteins). Secondly, this study offers the first complex proteomic data on not only the E. nipponicum but within the whole class of Monogenea, which was from this point of view until recently neglected.


Assuntos
Mucosa Intestinal/metabolismo , Tecido Parenquimatoso/metabolismo , Platelmintos/metabolismo , Proteoma/análise , Proteômica/métodos , Animais , Carpas/parasitologia , Catepsinas/análise , Catepsinas/metabolismo , Cromatografia Líquida de Alta Pressão , Brânquias/parasitologia , Microdissecção e Captura a Laser , Peptídeo Hidrolases/análise , Peptídeo Hidrolases/metabolismo , Espectrometria de Massas em Tandem
10.
Food Chem ; 330: 127324, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32569938

RESUMO

Enzymes currently used in cheesemaking have various drawbacks, and there is a continual need to find new coagulants. This study describes the extraction and biochemical characterization of two proteases from the red alga Gracilaria edulis. The proteases were extracted with phosphate buffer and partially purified by ammonium sulphate precipitation and dialysis. The enzymes exhibited optimum caseinolytic activity at 60 °C and a pH range of 6-8. They showed a high ratio of milk-clotting over caseinolytic activity, indicating they had an excellent milk-clotting ability. The proteases were confirmed to be serine protease and metalloprotease with molecular weight (MW) of 44 and 108 kDa. They exhibited high hydrolytic activity on κ-caseins, cleaving κ-casein at four main sites, one of which being the same as that of calf rennet, which is the first reported for an algal protease. The findings demonstrated that the proteases could potentially be used as a milk coagulant in cheesemaking.


Assuntos
Caseínas/metabolismo , Gracilaria/enzimologia , Peptídeo Hidrolases/isolamento & purificação , Peptídeo Hidrolases/metabolismo , Alga Marinha/enzimologia , Sulfato de Amônio , Animais , Caseínas/química , Fracionamento Químico , Quimosina/metabolismo , Eletroforese em Gel de Poliacrilamida , Gracilaria/química , Concentração de Íons de Hidrogênio , Hidrólise , Leite/química , Leite/metabolismo , Peso Molecular , Peptídeo Hidrolases/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/metabolismo , Alga Marinha/química , Serina Proteases/química , Serina Proteases/isolamento & purificação , Serina Proteases/metabolismo , Espectrometria de Massas em Tandem , Temperatura
11.
Nat Commun ; 11(1): 3196, 2020 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-32581215

RESUMO

T-cell bispecific antibodies (TCBs) crosslink tumor and T-cells to induce tumor cell killing. While TCBs are very potent, on-target off-tumor toxicity remains a challenge when selecting targets. Here, we describe a protease-activated anti-folate receptor 1 TCB (Prot-FOLR1-TCB) equipped with an anti-idiotypic anti-CD3 mask connected to the anti-CD3 Fab through a tumor protease-cleavable linker. The potency of this Prot- FOLR1-TCB is recovered following protease-cleavage of the linker releasing the anti-idiotypic anti-CD3 scFv. In vivo, the Prot-FOLR1-TCB mediates antitumor efficacy comparable to the parental FOLR1-TCB whereas a noncleavable control Prot-FOLR1-TCB is inactive. In contrast, killing of bronchial epithelial and renal cortical cells with low FOLR1 expression is prevented compared to the parental FOLR1-TCB. The findings are confirmed for mesothelin as alternative tumor antigen. Thus, masking the anti-CD3 Fab fragment with an anti-idiotypic mask and cleavage of the mask by tumor-specific proteases can be applied to enhance specificity and safety of TCBs.


Assuntos
Anticorpos Biespecíficos/imunologia , Anticorpos Biespecíficos/metabolismo , Complexo CD3/imunologia , Receptor 1 de Folato/imunologia , Peptídeo Hidrolases/metabolismo , Linfócitos T/imunologia , Animais , Anticorpos Biespecíficos/química , Anticorpos Biespecíficos/uso terapêutico , Linhagem Celular Tumoral , Proteínas Ligadas por GPI/imunologia , Humanos , Imunoterapia , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Terapia de Alvo Molecular , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Int J Nanomedicine ; 15: 3377-3389, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32494136

RESUMO

Background: Hepatitis C virus (HCV) infection is a major cause of hepatic diseases all over the world. This necessitates the need to discover novel anti-HCV drugs to overcome emerging drug resistance and liver complications. Purpose: Total extract and petroleum ether fraction of the marine sponge (Amphimedon spp.) were used for silver nanoparticle (SNP) synthesis to explore their HCV NS3 helicase- and protease-inhibitory potential. Methods: Characterization of the prepared SNPs was carried out with ultraviolet-visible spectroscopy, transmission electron microscopy, and Fourier-transform infrared spectroscopy. The metabolomic profile of different Amphimedon fractions was assessed using liquid chromatography coupled with high-resolution mass spectrometry. Fourteen known compounds were isolated and their HCV helicase and protease activities assessed using in silico modeling of their interaction with both HCV protease and helicase enzymes to reveal their anti-HCV mechanism of action. In vitro anti-HCV activity against HCV NS3 helicase and protease was then conducted to validate the computation results and compared to that of the SNPs. Results: Transmission electron-microscopy analysis of NPs prepared from Amphimedon total extract and petroleum ether revealed particle sizes of 8.22-14.30 nm and 8.22-9.97 nm, and absorption bands at λmax of 450 and 415 nm, respectively. Metabolomic profiling revealed the richness of Amphimedon spp. with different phytochemical classes. Bioassay-guided isolation resulted in the isolation of 14 known compounds with anti-HCV activity, initially revealed by docking studies. In vitro anti-HCV NS3 helicase and protease assays of both isolated compounds and NPs further confirmed the computational results. Conclusion: Our findings indicate that Amphimedon, total extract, petroleum ether fraction, and derived NPs are promising biosources for providing anti-HCV drug candidates, with nakinadine B and 3,4-dihydro-6-hydroxymanzamine A the most potent anti-HCV agents, possessing good oral bioavailability and penetration power.


Assuntos
Simulação por Computador , DNA Helicases/antagonistas & inibidores , Química Verde , Metabolômica , Nanopartículas Metálicas/química , Poríferos/química , Prata/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Alcanos/química , Animais , Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Oceano Índico , Nanopartículas Metálicas/ultraestrutura , Simulação de Acoplamento Molecular , Peptídeo Hidrolases/metabolismo , Inibidores de Proteases/farmacologia , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
13.
Am J Med Sci ; 360(2): 153-160, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32563568

RESUMO

BACKGROUND: Recent clinical trials' findings have revealed the therapeutic noninferiority of direct oral anticoagulant (DOAC) to standard therapy with vitamin K antagonist (VKA) in patients with pulmonary thromboembolism (PTE). However, few studies have quantitatively analyzed thrombus reduction in the pulmonary artery. METHODS: This observational study included 38 symptomatic PTE patients with stable hemodynamics. All patients received an intravenous heparin bolus followed by continual heparin injections immediately after the PTE diagnosis. The heparin was discontinued after edoxaban therapy began in the DOAC group (n = 22) or after the therapeutic range for the prothrombin time-international normalized ratio was achieved in the VKA group (n = 16). The thrombus volumes in the pulmonary arteries were quantitatively analyzed using contrast-enhanced computed tomography scans, and they were compared at baseline and at 2 weeks after admission. RESULTS: The pulmonary thrombus volumes declined in the VKA and DOAC groups from 7.9 to 4.2 cm3 (P = 0.048) and from 7.1 to 3.7 cm3 (P < 0.01), respectively, and the thrombus reduction rates did not differ significantly between the groups (-34% vs. -64%, respectively; P = 0.38). The fibrinogenolysis parameter changes during the14 days after admission were similar in both groups. Compared with the VKAgroup, the average hospital stay was 9days shorter in the DOAC group. There were no in-hospital deaths, and 1 case experienced major bleeding in the VKA group. CONCLUSIONS: In relation to pulmonary artery thrombus volume reduction, DOAC monotherapy for PTE may be comparable with standard therapy involving VKAs.


Assuntos
Anticoagulantes/uso terapêutico , Inibidores do Fator Xa/uso terapêutico , Artéria Pulmonar/diagnóstico por imagem , Embolia Pulmonar/diagnóstico por imagem , Embolia Pulmonar/tratamento farmacológico , Piridinas/uso terapêutico , Tiazóis/uso terapêutico , Varfarina/uso terapêutico , Idoso , Antitrombina III/metabolismo , Meios de Contraste , Feminino , Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Fibrinolisina/metabolismo , Heparina/uso terapêutico , Humanos , Coeficiente Internacional Normatizado , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Peptídeo Hidrolases/metabolismo , Tempo de Protrombina , Embolia Pulmonar/metabolismo , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Resultado do Tratamento , alfa 2-Antiplasmina/metabolismo
14.
Int J Infect Dis ; 98: 166-175, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32579907

RESUMO

OBJECTIVES: With the increasing number of people suffering from coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), there is a dire need to look for effective remedies against this pandemic. Drug repurposing seems to be the solution for the current situation. METHODS: In a quest to find a potential drug against this virus, 15 antimalarial drugs (including chloroquine) and 2413 US Food and Drug Administration-approved drugs were investigated for activity against both the protease and spike proteins of SARS-CoV-2 using an in silico approach. Molecular docking analysis followed by molecular dynamics simulation was performed to estimate the binding and stability of the complexes. RESULTS: This study identified a single drug - paromomycin - with activity against two targets of SARS-CoV-2, i.e., spike protein (S1) and protease domain. Paromomycin was found to have strong binding affinity for both targets of coronavirus. The results also showed that no antimalarial drug exhibited effective binding for either S1 or protease. CONCLUSIONS: This study found that paromomycin may be an effective dual targeting drug against coronavirus, as it binds not only to the protease domain of the virion, but also to the spike domain, with high stability. Furthermore, none of the antimalarial drugs showed strong binding affinity for either protease or the receptor binding domain (RBD).


Assuntos
Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/tratamento farmacológico , Paromomicina/uso terapêutico , Peptídeo Hidrolases/metabolismo , Pneumonia Viral/tratamento farmacológico , Inibidores de Proteases/uso terapêutico , Glicoproteína da Espícula de Coronavírus/antagonistas & inibidores , Betacoronavirus/metabolismo , Simulação por Computador , Reposicionamento de Medicamentos , Humanos , Simulação de Acoplamento Molecular , Pandemias , Peptídeo Hidrolases/química , Ligação Proteica
15.
Elife ; 92020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32452762

RESUMO

Molecular mimicry is an evolutionary strategy adopted by viruses to exploit the host cellular machinery. We report that SARS-CoV-2 has evolved a unique S1/S2 cleavage site, absent in any previous coronavirus sequenced, resulting in the striking mimicry of an identical FURIN-cleavable peptide on the human epithelial sodium channel α-subunit (ENaC-α). Genetic alteration of ENaC-α causes aldosterone dysregulation in patients, highlighting that the FURIN site is critical for activation of ENaC. Single cell RNA-seq from 66 studies shows significant overlap between expression of ENaC-α and the viral receptor ACE2 in cell types linked to the cardiovascular-renal-pulmonary pathophysiology of COVID-19. Triangulating this cellular characterization with cleavage signatures of 178 proteases highlights proteolytic degeneracy wired into the SARS-CoV-2 lifecycle. Evolution of SARS-CoV-2 into a global pandemic may be driven in part by its targeted mimicry of ENaC-α, a protein critical for the homeostasis of airway surface liquid, whose misregulation is associated with respiratory conditions.


Assuntos
Betacoronavirus/metabolismo , Infecções por Coronavirus/virologia , Canais Epiteliais de Sódio/metabolismo , Mimetismo Molecular , Peptídeo Hidrolases/metabolismo , Pneumonia Viral/virologia , Proteínas do Envelope Viral/metabolismo , Proteínas Virais/metabolismo , Betacoronavirus/genética , Betacoronavirus/patogenicidade , Canais Epiteliais de Sódio/genética , Interações Hospedeiro-Patógeno , Humanos , Pandemias , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/metabolismo , Proteólise , Especificidade por Substrato , Proteínas do Envelope Viral/genética , Proteínas Virais/genética
16.
Nat Biomed Eng ; 4(5): 560-571, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32393891

RESUMO

The oral administration of peptide drugs is hampered by their metabolic instability and limited intestinal uptake. Here, we describe a method for the generation of small target-specific peptides (less than 1,600 Da in size) that resist gastrointestinal proteases. By using phage display to screen large libraries of genetically encoded double-bridged peptides on protease-resistant fd bacteriophages, we generated a peptide inhibitor of the coagulation Factor XIa with nanomolar affinity that resisted gastrointestinal proteases in all regions of the gastrointestinal tract of mice after oral administration, enabling more than 30% of the peptide to remain intact, and small quantities of it to reach the blood circulation. We also developed a gastrointestinal-protease-resistant peptide antagonist for the interleukin-23 receptor, which has a role in the pathogenesis of Crohn's disease and ulcerative colitis. The de novo generation of targeted peptides that resist proteolytic degradation in the gastrointestinal tract should help the development of effective peptides for oral delivery.


Assuntos
Peptídeos/administração & dosagem , Peptídeos/uso terapêutico , Proteólise , Administração Oral , Sequência de Aminoácidos , Animais , Técnicas de Visualização da Superfície Celular , Cristalografia por Raios X , Feminino , Trato Gastrointestinal/metabolismo , Humanos , Isomerismo , Camundongos Endogâmicos BALB C , Modelos Moleculares , Peptídeo Hidrolases/metabolismo , Biblioteca de Peptídeos , Peptídeos/química , Estabilidade Proteica , Estrutura Secundária de Proteína , Receptores de Interleucina/antagonistas & inibidores , Receptores de Interleucina/metabolismo
17.
PLoS One ; 15(5): e0233048, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32453791

RESUMO

Panagrolaimus sp. DAW1, a nematode cultured from the Antarctic, has the extraordinary physiological ability to survive total intracellular freezing throughout all of its compartments. While a few other organisms, all nematodes, have subsequently also been found to survive freezing in this manner, P. sp. DAW1 has so far shown the highest survival rates. In addition, P. sp. DAW1 is also, depending on the rate or extent of freezing, able to undergo cryoprotective dehydration. In this study, the proteome of P. sp DAW1 is explored, highlighting a number of differentially expressed proteins and pathways that occur when the nematodes undergo intracellular freezing. Among the strongest signals after being frozen is an upregulation of proteases and the downregulation of cytoskeletal and antioxidant activity, the latter possibly accumulated before freezing much in the way the sugar trehalose has been shown to be stored during acclimation.


Assuntos
Aclimatação/fisiologia , Redes Reguladoras de Genes , Proteômica/métodos , Rabditídios/fisiologia , Animais , Antioxidantes/metabolismo , Temperatura Baixa , Regulação da Expressão Gênica , Proteínas de Helminto/metabolismo , Peptídeo Hidrolases/metabolismo , Mapas de Interação de Proteínas
18.
Toxicon ; 180: 43-48, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32298663

RESUMO

Zearalenone, an oestogenic mycotoxin produced by Fusarium sp., occurs naturally in agricultural commodities. Economic losses and health concerns associated to mycotoxins has attracted research interest towards exploring novel approaches to detoxify mycotoxin-contaminated food and feed. The aim of the present work was to study the ability of 11 aflatoxin-degrading Bacillus strains to degrade ZEA. In addition, a qualitative assessment of protease, amylase and cellulase activity of the studied Bacillus strains was made. All strains were able to degrade 58-96.9% ZEA after 72 h. Toxicity towards Artemia salina was significantly reduced (P < 0.0001). Degradation extracts fluorescence decreased 50% indicating a probable cleavage of the lactone ring. Strains RC1A, RC3A and RC6A showed a remarkable enzymatic activity, showing potential to be used as feed additives.


Assuntos
Aflatoxinas/metabolismo , Amilases/metabolismo , Bacillus/metabolismo , Celulases/metabolismo , Peptídeo Hidrolases/metabolismo , Zearalenona/metabolismo , Agricultura , Inativação Metabólica
19.
Food Chem ; 321: 126689, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32259732

RESUMO

Peptides and free amino acids are naturally generated in dry-cured ham as a consequence of proteolysis phenomenon exerted by muscle peptidases. The generation of bioactive peptides in different types of dry-cured ham produced in Spain, Italy and China is reviewed in this manuscript. Major muscle proteins are extensively hydrolysed firstly by endogenous endo-peptidases followed by the successive action of exo-peptidases, mainly, tri- and di-peptidylpeptidases, aminopeptidases and carboxypeptidases. Such proteolysis is very intense and consists of the generation of large amounts of free amino acids and a good number of peptides with different sequences and lengths, some of them exerting relevant bioactivities like angiotensin converting enzyme inhibitory activity, antioxidant activity, di-peptidylpeptidase IV inhibitory activity among other and in vivo antihypertensive, hypoglycemic or anti-inflammatory activity. This manuscript reviews the recent findings showing that dry-cured ham constitutes a good source of natural bioactive peptides that have potential benefit for human health.


Assuntos
Carne de Porco , Aminoácidos/metabolismo , Animais , Hidrólise , Produtos da Carne/análise , Peptídeo Hidrolases/metabolismo , Peptídeos/química , Proteólise , Suínos
20.
Arch Microbiol ; 202(7): 1669-1675, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32285165

RESUMO

Archaea swim using archaella that are domain-specific rotary type IV pilus-like appendages. The structural components of the archaellum filament are archaellins, initially made as preproteins with type IV pilin-like signal peptides which are removed by signal peptidases that are homologues of prepilin peptidases that remove signal peptides from type IV pilins. N-terminal sequences of archaellins, including the signal peptide cleavage site, are conserved and various positions have been previously shown to be critical for signal peptide removal. Archaellins have an absolute conservation of glycine at the + 3 position from the signal peptide cleavage site. To investigate its role in signal peptide cleavage, I used archaellin variants in which the + 3 glycine was mutated to all other possibilities in in vitro cleavage reactions. Cleavage was observed with ten different amino acids at the + 3 position, indicating that the observed glycine conservation is not required for this essential processing step.


Assuntos
Proteínas Arqueais/genética , Proteínas Arqueais/metabolismo , Mathanococcus/enzimologia , Mathanococcus/genética , Peptídeo Hidrolases/genética , Peptídeo Hidrolases/metabolismo , Proteínas Arqueais/química , Proteínas de Fímbrias/metabolismo , Fímbrias Bacterianas/enzimologia , Mathanococcus/metabolismo , Sinais Direcionadores de Proteínas
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