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1.
PLoS Pathog ; 20(1): e1011988, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38289966

RESUMO

Autophagy and Cell wall integrity (CWI) signaling are critical stress-responsive processes during fungal infection of host plants. In the rice blast fungus Magnaporthe oryzae, autophagy-related (ATG) proteins phosphorylate CWI kinases to regulate virulence; however, how autophagy interplays with CWI signaling to coordinate such regulation remains unknown. Here, we have identified the phosphorylation of ATG protein MoAtg4 as an important process in the coordination between autophagy and CWI in M. oryzae. The ATG kinase MoAtg1 phosphorylates MoAtg4 to inhibit the deconjugation and recycling of the key ATG protein MoAtg8. At the same time, MoMkk1, a core kinase of CWI, also phosphorylates MoAtg4 to attenuate the C-terminal cleavage of MoAtg8. Significantly, these two phosphorylation events maintain proper autophagy levels to coordinate the development and pathogenicity of the rice blast fungus.


Assuntos
Ascomicetos , Magnaporthe , Oryza , Fosforilação , Virulência , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Magnaporthe/metabolismo , Autofagia , Parede Celular/metabolismo , Oryza/microbiologia , Doenças das Plantas/microbiologia , Regulação Fúngica da Expressão Gênica
2.
PLoS Genet ; 19(5): e1010748, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37186579

RESUMO

The rice blast fungus Magnaporthe oryzae forms specialized infectious structures called appressoria that breach host cells to initiate infection. Previous studies demonstrated that the regulator of G-protein signaling (RGS)-like protein MoRgs7 undergoes endocytosis upon fungal sensing of hydrophobic environmental cues to activate cAMP signaling required for appressorium formation. However, the mechanism by which MoRgs7 internalizes and its fate remains undetermined. We here show that MoSep1, a conserved protein kinase of Mitotic Exit Network (MEN), phosphorylates MoRgs7 to regulate its function. MoRgs7 phosphorylation determines its interaction with MoCrn1, a coronin-like actin-binding protein homolog that also modulates the internalization of MoRgs7. Importantly, the endocytic transport of MoRgs7 is critical for its GTPase-activating protein (GAP) function important in cAMP signaling. Together, our findings revealed a novel mechanism by which M. oryzae activates MoRgs7-mediated hydrophobic cue-sensing signal transduction involving protein phosphorylation and endocytic transport to govern appressorium formation and fungal pathogenicity.


Assuntos
Magnaporthe , Oryza , Humanos , Fosforilação , Sinais (Psicologia) , Magnaporthe/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Oryza/metabolismo , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Regulação Fúngica da Expressão Gênica
3.
J Virol ; 98(5): e0025324, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38591878

RESUMO

Coronavirus (CoV) 3C-like protease (3CLpro) is essential for viral replication and is involved in immune escape by proteolyzing host proteins. Deep profiling the 3CLpro substrates in the host proteome extends our understanding of viral pathogenesis and facilitates antiviral drug discovery. Here, 3CLpro from porcine epidemic diarrhea virus (PEDV), an enteropathogenic CoV, was used as a model which to identify the potential 3CLpro cleavage motifs in all porcine proteins. We characterized the selectivity of PEDV 3CLpro at sites P5-P4'. We then compiled the 3CLpro substrate preferences into a position-specific scoring matrix and developed a 3CLpro profiling strategy to delineate the protein substrate landscape of CoV 3CLpro. We identified 1,398 potential targets in the porcine proteome containing at least one putative cleavage site and experimentally validated the reliability of the substrate degradome. The PEDV 3CLpro-targeted pathways are involved in mRNA processing, translation, and key effectors of autophagy and the immune system. We also demonstrated that PEDV 3CLpro suppresses the type 1 interferon (IFN-I) cascade via the proteolysis of multiple signaling adaptors in the retinoic acid-inducible gene I (RIG-I) signaling pathway. Our composite method is reproducible and accurate, with an unprecedented depth of coverage for substrate motifs. The 3CLpro substrate degradome establishes a comprehensive substrate atlas that will accelerate the investigation of CoV pathogenicity and the development of anti-CoV drugs.IMPORTANCECoronaviruses (CoVs) are major pathogens that infect humans and animals. The 3C-like protease (3CLpro) encoded by CoV not only cleaves the CoV polyproteins but also degrades host proteins and is considered an attractive target for the development of anti-CoV drugs. However, the comprehensive characterization of an atlas of CoV 3CLpro substrates is a long-standing challenge. Using porcine epidemic diarrhea virus (PEDV) 3CLpro as a model, we developed a method that accurately predicts the substrates of 3CLpro and comprehensively maps the substrate degradome of PEDV 3CLpro. Interestingly, we found that 3CLpro may simultaneously degrade multiple molecules responsible for a specific function. For instance, it cleaves at least four adaptors in the RIG-I signaling pathway to suppress type 1 interferon production. These findings highlight the complexity of the 3CLpro substrate degradome and provide new insights to facilitate the development of anti-CoV drugs.


Assuntos
Proteases 3C de Coronavírus , Vírus da Diarreia Epidêmica Suína , Animais , Humanos , Proteases 3C de Coronavírus/metabolismo , Infecções por Coronavirus/virologia , Infecções por Coronavirus/metabolismo , Infecções por Coronavirus/veterinária , Células HEK293 , Interferon Tipo I/metabolismo , Proteólise , Proteoma/metabolismo , Especificidade por Substrato , Suínos , Proteínas Virais/metabolismo , Proteínas Virais/genética , Replicação Viral
4.
J Virol ; 98(2): e0181423, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38289103

RESUMO

HDAC6, a structurally and functionally unique member of the histone deacetylase (HDAC) family, is an important host factor that restricts viral infection. The broad-spectrum antiviral activity of HDAC6 makes it a potent antiviral agent. Previously, we found that HDAC6 functions to antagonize porcine deltacoronavirus (PDCoV), an emerging enteropathogenic coronavirus with zoonotic potential. However, the final outcome is typically a productive infection that materializes as cells succumb to viral infection, indicating that the virus has evolved sophisticated mechanisms to combat the antiviral effect of HDAC6. Here, we demonstrate that PDCoV nonstructural protein 5 (nsp5) can cleave HDAC6 at glutamine 519 (Q519), and cleavage of HDAC6 was also detected in the context of PDCoV infection. More importantly, the anti-PDCoV activity of HDAC6 was damaged by nsp5 cleavage. Mechanistically, the cleaved HDAC6 fragments (amino acids 1-519 and 520-1159) lost the ability to degrade PDCoV nsp8 due to their impaired deacetylase activity. Furthermore, nsp5-mediated cleavage impaired the ability of HDAC6 to activate RIG-I-mediated interferon responses. We also tested three other swine enteric coronaviruses (transmissible gastroenteritis virus, porcine epidemic diarrhea virus, and swine acute diarrhea syndrome-coronavirus) and found that all these coronaviruses have adopted similar mechanisms to cleave HDAC6 in both an overexpression system and virus-infected cells, suggesting that cleavage of HDAC6 is a common strategy utilized by swine enteric coronaviruses to antagonize the host's antiviral capacity. Together, these data illustrate how swine enteric coronaviruses antagonize the antiviral function of HDAC6 to maintain their infection, providing new insights to the interaction between virus and host.IMPORTANCEViral infections and host defenses are in constant opposition. Once viruses combat or evade host restriction, productive infection is achieved. HDAC6 is a broad-spectrum antiviral protein that has been demonstrated to inhibit many viruses, including porcine deltacoronavirus (PDCoV). However, whether HDAC6 is reciprocally targeted and disabled by viruses remains unclear. In this study, we used PDCoV as a model and found that HDAC6 is targeted and cleaved by nsp5, a viral 3C-like protease. The cleaved HDAC6 loses its deacetylase activity as well as its ability to degrade viral proteins and activate interferon responses. Furthermore, this cleavage mechanism is shared among other swine enteric coronaviruses. These findings shed light on the intricate interplay between viruses and HDAC6, highlighting the strategies employed by viruses to evade host antiviral defenses.


Assuntos
Infecções por Coronavirus , Coronavirus , Doenças dos Suínos , Animais , Coronavirus/fisiologia , Infecções por Coronavirus/veterinária , Infecções por Coronavirus/virologia , Deltacoronavirus , Interferons/metabolismo , Suínos , Doenças dos Suínos/virologia
5.
Evol Dev ; 26(3): e12476, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38654704

RESUMO

Tardigrades, commonly known as water bears, are enigmatic organisms characterized by their remarkable resilience to extreme environments despite their simple and compact body structure. To date, there is still much to understand about their evolutionary and developmental features contributing to their special body plan and abilities. This research provides preliminary insights on the conserved and specific gene expression patterns during embryonic development of water bears, focusing on the species Hypsibius exemplaris. The developmental dynamic expression analysis of the genes with various evolutionary age grades indicated that the mid-conserved stage of H. exemplaris corresponds to the period of ganglia and midgut development, with the late embryonic stage showing a transition from non-conserved to conserved state. Additionally, a comparison with Drosophila melanogaster highlighted the absence of certain pathway nodes in development-related pathways, such as Maml and Hairless, which are respectively the transcriptional co-activator and co-repressor of NOTCH regulated genes. We also employed Weighted Gene Co-expression Network Analysis (WGCNA) to investigate the expression patterns of tardigrade-specific genes during embryo development. Our findings indicated that the module containing the highest proportion of tardigrade-specific genes (TSGs) exhibits high expression levels before the mid-conserved stage, potentially playing a role in glutathione and lipid metabolism. These functions may be associated to the ecdysone synthesis and storage cell formation, which is unique to tardigrades.


Assuntos
Desenvolvimento Embrionário , Regulação da Expressão Gênica no Desenvolvimento , Tardígrados , Animais , Tardígrados/genética , Tardígrados/embriologia , Desenvolvimento Embrionário/genética , Embrião não Mamífero/metabolismo
6.
New Phytol ; 242(1): 211-230, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38326975

RESUMO

Microbe-produced secondary metabolite phenazine-1-carboxylic acid (PCA) facilitates pathogen virulence and defense mechanisms against competitors. Magnaporthe oryzae, a causal agent of the devastating rice blast disease, needs to compete with other phyllosphere microbes and overcome host immunity for successful colonization and infection. However, whether M. oryzae produces PCA or it has any other functions remains unknown. Here, we found that the MoPHZF gene encodes the phenazine biosynthesis protein MoPhzF, synthesizes PCA in M. oryzae, and regulates appressorium formation and host virulence. MoPhzF is likely acquired through an ancient horizontal gene transfer event and has a canonical function in PCA synthesis. In addition, we found that PCA has a role in suppressing the accumulation of host-derived reactive oxygen species (ROS) during infection. Further examination indicated that MoPhzF recruits both the endoplasmic reticulum membrane protein MoEmc2 and the regulator of G-protein signaling MoRgs1 to the plasma membrane (PM) for MoRgs1 phosphorylation, which is a critical regulatory mechanism in appressorium formation and pathogenicity. Collectively, our studies unveiled a canonical function of MoPhzF in PCA synthesis and a noncanonical signaling function in promoting appressorium formation and host infection.


Assuntos
Ascomicetos , Magnaporthe , Oryza , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Oryza/metabolismo , Fenazinas/metabolismo , Doenças das Plantas/genética
7.
Bioorg Med Chem Lett ; 99: 129615, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38199331

RESUMO

Monocyclic ß-lactams are stable to a number of ß-lactamases and are the focus of researchers for the development of antibacterial drugs, particularly against Enterobacterales. We recently synthesized and reported the bactericidal activity of diverse series of aztreonam appended with amidine moieties as siderophores. One of the derivatives exhibiting the highest MIC value in vitro was selected for further preclinical studies. The compound DPI-2016 was reassessed for its synthetic routes and methods that were improved to find the maximum final yields aimed at large-scale synthesis. In addition, the results of the pharmacological studies were determined with reference to aztreonam. It has been found that the compound DPI-2016 showed comparable or slightly improved ADMET as well as pharmacokinetic parameters to aztreonam. It is estimated that the compound could be a potential lead for further clinical evaluation.


Assuntos
Aztreonam , Monobactamas , Monobactamas/farmacologia , Aztreonam/farmacologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , beta-Lactamases , Testes de Sensibilidade Microbiana
8.
RNA Biol ; 21(1): 32-45, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39115224

RESUMO

Interactions between double-stranded RNA (dsRNA) and proteins play an important role in cellular homeostasis by regulating the editing, stability, and splicing of intracellular RNA. The identification of dsRNA-binding proteins (dsRBPs) is key; however, it has long been challenging to purify dsRBPs from cells. In this study, we developed a novel method, dsRBPC (dsRNA-binding protein capture), to purify cellular dsRBPs based on classic phase separation purification procedures. A global dsRNA-binding proteome of LLC-PK1 cells was obtained, and we identified 1326 dsRBPs, including 1303 putative novel dsRBPs. Functional analyses suggested that these enriched dsRBPs are mainly associated with rRNA processing, RNA splicing, transcriptional regulation, and nucleocytoplasmic transport. We also found that the ARM (armadillo/beta-catenin-like repeats) motif is a previously unknown dsRNA-binding domain, as demonstrated by biochemical experiments. Collectively, this study provides a useful approach for dsRBP identification and the discovery of a global dsRNA-binding proteome to comprehensively map the dsRNA - protein interaction network.


Assuntos
RNA de Cadeia Dupla , Proteínas de Ligação a RNA , RNA de Cadeia Dupla/metabolismo , RNA de Cadeia Dupla/genética , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/química , Animais , Proteoma/metabolismo , Ligação Proteica , Suínos , Linhagem Celular , Splicing de RNA , Separação de Fases
9.
J Thromb Thrombolysis ; 57(3): 428-436, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38280936

RESUMO

This preliminary study investigated the feasibility of a combined model constructed using radiomic features based on computed tomography (CT) and clinical features to predict adverse clinical outcomes in acute pulmonary embolism (APE). Currently, there is no widely recognized predictive model. Patients with confirmed APE who underwent CT pulmonary angiography were retrospectively categorized into good and poor prognosis groups. Seventy-four patients were randomized into a training (n = 51) or validation (n = 23) cohort. Feature extraction was performed using 3D-Slicer software. The least absolute shrinkage and selection operator regression was used to identify the optimal radiomics features and calculate the radiomics scores; subsequently, the radiomics model was developed. A combined predictive model was constructed based on radiomics scores and selected clinical features. The predictive efficacy of the three models (radiomics, clinical and combined) was assessed by plotting receiver operating characteristic curves. Furthermore, the calibration curves were graphed and the decision curve analysis was performed. Four radiomic features were screened to calculate the radiomic score. Right ventricular to left ventricular ratio (RV/LV) ≥ 1.0 and radiomics score were independent risk factors for adverse clinical outcomes. In the training and validation cohorts, the areas under the curve (AUCs) for the RV/LV ≥ 1.0 (clinical) and radiomics score prediction models were 0.778 and 0.833 and 0.907 and 0.817, respectively. The AUCs for the combined model of RV/LV ≥ 1.0 and radiomics score were 0.925 and 0.917, respectively. The combined and radiomics models had high clinical assessment efficacy for predicting adverse clinical outcomes in APE, demonstrating the clinical utility of both models. Calibration curves exhibited a strong level of consistency between the predictive and observed probabilities of poor and good prognoses in the combined model. The combined model of RV/LV ≥ 1.0 and radiomics score based on CT could accurately and non-invasively predict adverse clinical outcomes in patients with APE.


Assuntos
Hominidae , Embolia Pulmonar , Animais , Humanos , Doença Aguda , Embolia Pulmonar/diagnóstico por imagem , Embolia Pulmonar/terapia , Radiômica , Estudos Retrospectivos , Fatores de Risco , Tomografia Computadorizada por Raios X
10.
Phys Chem Chem Phys ; 25(46): 32173-32183, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-37986618

RESUMO

Infrared photodissociation spectroscopy has been used to investigate CrFe(CO)n- (n = 4-9) clusters in the gas phase. Comparison of the observed spectra in the carbonyl stretching frequency region with those predicted for low-lying isomers by DFT calculations showed that the observed CrFe(CO)n- (n = 4-8) clusters could be characterized to have Cr-Fe bonded (OC)4Fe-Cr(CO)n-4 structures. The coexistence of isomers with the (OC)Fe-Cr(CO)5 and (OC)3Fe-Cr(CO)4 structures was also observed for CrFe(CO)6- and CrFe(CO)7- anions, respectively. The CrFe(CO)n- (n = 4-8) complexes were strongly bonded systems. The CrFe(CO)8- complex was a coordination-saturated cluster, and the CrFe(CO)9- anion was characterized to contain a CrFe(CO)8- core tagged by one CO molecule. Bonding analysis revealed that the Cr-Fe bonds in the CrFe(CO)n- (n = 4-8) clusters were predominantly σ-type single bonds. The iron center in the Fe(CO)4 moiety and the chromium center in the Cr(CO)5 moiety fulfilled the 18-electron configuration for the CrFe(CO)n- (n = 4-6) clusters. As in the CrFe(CO)n- (n = 7, 8) complexes, the iron center in the Fe(CO)4 moiety exhibited a 17-electron configuration, while the chromium center in the Cr(CO)4 moiety exhibited a 16-electron configuration. These findings provide valuable insights into the structure and bonding mechanism of heterometallic carbonyl clusters.

11.
J Thromb Thrombolysis ; 56(4): 529-537, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37548900

RESUMO

BACKGROUND: Computed tomography pulmonary angiography (CTPA) yields indices, such as the right ventricular/left ventricular (RV/LV) ratio > 1.0, which are commonly used for risk stratification of patients with acute pulmonary embolism (APE). Although pulmonary artery elasticity (PAE) has been previously described, its relationship with right ventricular dysfunction (RVD) has not been explored. Here, we investigated whether PAE, measured using CTPA, is associated with RVD. METHODS: Patients who underwent retrospective electrocardiogram-gated CTPA and had a definitive diagnosis of APE were included in the study. The subjects were classified into RVD and non-RVD groups according to the RVD on echocardiography. PAE, involving aortic distensibility (AD), aortic compliance (AC), and aortic stiffness (ASI), and right heart function indices were compared between the two groups, and their correlations were examined. Receiver operating characteristic (ROC) curves were generated to evaluate the specificity and sensitivity of the RVD prediction. RESULTS: Thirty-five patients with APE were enrolled in the study (RVD: 18, non-RVD: 17). The groups showed no significant differences in age, sex, number of patients receiving thrombolysis, and number of high-risk conditions (P > 0.05). Regarding PAE parameters, AD was significantly reduced in the RVD group compared to that in the non-RVD group (P < 0.05), whereas AC and ASI were not statistically different (P > 0.05). The ratio of the maximum cross-sectional area of PA and AA (PA/AAmax),the ratio of the minimum cross-sectional area of PA and AA(PA/AAmin), diameter of the coronary sinus, RV/LV diameter, RV/Lvarea, the ratio of the end-diastolic volume of right ventricular and left ventricular (RV/LVDV), the ratio of the end-systolic volume of right ventricular and left ventricular (RV/LVSV) were significantly greater in the RVD group than in the non-RVD group (P < 0.05). Correlation analysis of AD and right heart function parameters showed that AD was negatively correlated with PA/AAmax, PA/AAmin, RV/LV diameter, RV/LVDV, and PAE measured by ultrasound, with correlation coefficients ranging from - 0.336 to - 0.580 (P < 0.05). The ROC curves of AD and RV/LVdiameter to predict RVD had areas under the curve of 0.748 and 0.712, sensitivities of 82.35% and 70.59%, specificities of 66.67% and 72.22%, and cutoff values of 4.9433 and 1.1105, respectively. CONCLUSION: AD obtained by retrospective ECG-gated CTPA may be helpful in assessing RVD in patients with APE while accurately diagnosing APE. It contributes to timely diagnosis and treatment and improves the prognosis of patients with APE.


Assuntos
Hominidae , Hipertensão Pulmonar , Embolia Pulmonar , Disfunção Ventricular Direita , Humanos , Animais , Artéria Pulmonar/diagnóstico por imagem , Estudos Retrospectivos , Embolia Pulmonar/diagnóstico por imagem , Embolia Pulmonar/complicações
12.
Int J Mol Sci ; 24(19)2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37834265

RESUMO

Deinococcus radiodurans (D. radiodurans) can tolerate various extreme environments including radiation. Protein phosphorylation plays an important role in radiation resistance mechanisms; however, there is currently a lack of systematic research on this topic in D. radiodurans. Based on label-free (phospho)proteomics, we explored the dynamic changes of D. radiodurans under various doses of heavy ion irradiation and at different time points. In total, 2359 proteins and 1110 high-confidence phosphosites were identified, of which 66% and 23% showed significant changes, respectively, with the majority being upregulated. The upregulated proteins at different states (different doses or time points) were distinct, indicating that the radio-resistance mechanism is dose- and stage-dependent. The protein phosphorylation level has a much higher upregulation than protein abundance, suggesting phosphorylation is more sensitive to irradiation. There were four distinct dynamic changing patterns of phosphorylation, most of which were inconsistent with protein levels. Further analysis revealed that pathways related to RNA metabolism and antioxidation were activated after irradiation, indicating their importance in radiation response. We also screened some key hub phosphoproteins and radiation-responsive kinases for further study. Overall, this study provides a landscape of the radiation-induced dynamic change of protein expression and phosphorylation, which provides a basis for subsequent functional and applied studies.


Assuntos
Deinococcus , Íons Pesados , Deinococcus/genética , Deinococcus/metabolismo , Proteoma/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Processamento de Proteína Pós-Traducional
13.
Molecules ; 27(12)2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35744953

RESUMO

Antibacterial resistance towards the ß-lactam (BL) drugs is now ubiquitous, and there is a major global health concern associated with the emergence of new ß-lactamases (BLAs) as the primary cause of resistance. In addition to the development of new antibacterial drugs, ß-lactamase inhibition is an alternative modality that can be implemented to tackle this resistance channel. This strategy has successfully revitalized the efficacy of a number of otherwise obsolete BLs since the discovery of the first ß-lactamase inhibitor (BLI), clavulanic acid. Over the years, ß-lactamase inhibition research has grown, leading to the introduction of new synthetic inhibitors, and a few are currently in clinical trials. Of note, the 1, 6-diazabicyclo [3,2,1]octan-7-one (DBO) scaffold gained the attention of researchers around the world, which finally culminated in the approval of two BLIs, avibactam and relebactam, which can successfully inhibit Ambler class A, C, and D ß-lactamases. Boronic acids have shown promise in coping with Ambler class B ß-lactamases in recent research, in addition to classes A, C, and D with the clinical use of vaborbactam. This review focuses on the further developments in the synthetic strategies using DBO as well as boronic acid derivatives. In addition, various other potential serine- and metallo- ß-lactamases inhibitors that have been developed in last few years are discussed briefly as well. Furthermore, binding interactions of the representative inhibitors have been discussed based on the crystal structure data of inhibitor-enzyme complex, published in the literature.


Assuntos
Compostos Azabicíclicos , beta-Lactamases , Adaptação Psicológica , Antibacterianos/química , Antibacterianos/farmacologia , Compostos Azabicíclicos/química , Compostos Azabicíclicos/farmacologia , Farmacorresistência Bacteriana , Testes de Sensibilidade Microbiana , Inibidores de beta-Lactamases/química , Inibidores de beta-Lactamases/farmacologia , beta-Lactamases/química
14.
Bioorg Med Chem Lett ; 39: 127878, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33636305

RESUMO

Monobactams play an important role in antibiotic drug discovery. Based on the structural characteristics of aztreonam and its biological targets, six new monobactam derivatives (2a-c and 3a-c) were synthesized and their in vitro antibacterial activities were investigated. Compounds 2a-c showed higher activities against tested gram-negative bacteria than that of parent aztreonam. Monobactam 2c exhibited the most potent activities, with MIC ranging from 0.25 to 2 µg/mL against most bacteria.


Assuntos
Antibacterianos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Monobactamas/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Estrutura Molecular , Monobactamas/síntese química , Monobactamas/química , Relação Estrutura-Atividade
15.
Beilstein J Org Chem ; 17: 711-718, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33777246

RESUMO

The diazabicyclooctane (DBO) scaffold is the backbone of non-ß-lactam-based second generation ß-lactamase inhibitors. As part of our efforts, we have synthesized a series of DBO derivatives A1-23 containing amidine substituents at the C2 position of the bicyclic ring. These compounds, alone and in combination with meropenem, were tested against ten bacterial strains for their antibacterial activity in vitro. All compounds did not show antibacterial activity when tested alone (MIC >64 mg/L), however, they exhibited a moderate inhibition activity in the presence of meropenem by lowering its MIC values. The compound A12 proved most potent among the other counterparts against all bacterial species with MIC from <0.125 mg/L to 2 mg/L, and is comparable to avibactam against both E. coli strains with a MIC value of <0.125 mg/L.

16.
FASEB J ; 33(12): 14575-14587, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31690127

RESUMO

Coronaviruses (CoVs) infect humans and multiple other animal species, causing highly prevalent and severe diseases. 3C-like proteases (3CLpros) from CoVs (also called main proteases) are essential for viral replication and are also involved in polyprotein cleavage and immune regulation, making them attractive and effective targets for the development of antiviral drugs. Herein, the 3CLpro from the porcine epidemic diarrhea virus, an enteropathogenic CoV, was used as a model to identify novel crucial residues for enzyme activity. First, we established a rapid, sensitive, and efficient luciferase-based biosensor to monitor the activity of PDEV 3CLproin vivo. Using this luciferase biosensor, along with confirming the well-known catalytic residues (His41 and Cys144), we identified 4 novel proteolytically inactivated mutants of PDEV 3CLpro, which was also confirmed in mammalian cells by biochemical experiments. Our molecular dynamics (MD) simulations showed that the hydrogen bonding interactions occurring within and outside of the protease's active site and the dynamic fluctuations of the substrate, especially the van der Waals contacts, were drastically altered, a situation related to the loss of 3CLpro activity. These data suggest that changing the intermolecular dynamics in protein-substrate complexes eliminates the mechanism underlying the protease activity. The discovery of novel crucial residues for enzyme activity in the binding pocket could potentially provide more druggable sites for the design of protease inhibitors. In addition, our in-depth study of the dynamic substrate's envelope model using MD simulations is an approach that could augment the discovery of new inhibitors against 3CLpro in CoVs and other viral 3C proteases.-Zhou, J., Fang, L., Yang, Z., Xu, S., Lv, M., Sun, Z., Chen, J., Wang, D., Gao, J., Xiao, S. Identification of novel proteolytically inactive mutations in coronavirus 3C-like protease using a combined approach.


Assuntos
Coronavirus/enzimologia , Cisteína Endopeptidases/metabolismo , Mutação , Proteínas Virais/metabolismo , Proteases Virais 3C , Sequência de Aminoácidos , Linhagem Celular , Coronavirus/genética , Cisteína Endopeptidases/química , Cisteína Endopeptidases/genética , Ativação Enzimática , Humanos , Ligação de Hidrogênio , Modelos Moleculares , Estrutura Terciária de Proteína , Proteínas Virais/química , Proteínas Virais/genética
17.
Bioorg Med Chem ; 28(1): 115194, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31786008

RESUMO

Inhibition of BACE1 has become an important strategy in the quest for disease modifying agents to slow the progression of Alzheimer's disease. We previously reported the fragment-based discovery of LY2811376, the first BACE1 inhibitor reported to demonstrate robust reduction of human CSF Aß in a Phase I clinical trial. We also reported on the discovery of LY2886721, a potent BACE1 inhibitor that reached phase 2 clinical trials. Herein we describe the preparation and structure activity relationships (SAR) of a series of BACE1 inhibitors utilizing trans-cyclopropyl moieties as conformational constraints. The design, details of the stereochemically complex organic synthesis, and biological activity of these BACE1 inhibitors is described.


Assuntos
Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Ácido Aspártico Endopeptidases/antagonistas & inibidores , Ciclopropanos/farmacologia , Inibidores de Proteases/farmacologia , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Ácido Aspártico Endopeptidases/metabolismo , Cristalografia por Raios X , Ciclopropanos/síntese química , Ciclopropanos/química , Relação Dose-Resposta a Droga , Humanos , Ligantes , Modelos Moleculares , Conformação Molecular , Inibidores de Proteases/síntese química , Inibidores de Proteases/química , Relação Estrutura-Atividade
18.
J Neurosci ; 35(3): 1199-210, 2015 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-25609634

RESUMO

BACE1 is a key protease controlling the formation of amyloid ß, a peptide hypothesized to play a significant role in the pathogenesis of Alzheimer's disease (AD). Therefore, the development of potent and selective inhibitors of BACE1 has been a focus of many drug discovery efforts in academia and industry. Herein, we report the nonclinical and early clinical development of LY2886721, a BACE1 active site inhibitor that reached phase 2 clinical trials in AD. LY2886721 has high selectivity against key off-target proteases, which efficiently translates in vitro activity into robust in vivo amyloid ß lowering in nonclinical animal models. Similar potent and persistent amyloid ß lowering was observed in plasma and lumbar CSF when single and multiple doses of LY2886721 were administered to healthy human subjects. Collectively, these data add support for BACE1 inhibition as an effective means of amyloid lowering and as an attractive target for potential disease modification therapy in AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Peptídeos beta-Amiloides/metabolismo , Ácido Aspártico Endopeptidases/antagonistas & inibidores , Compostos Heterocíclicos com 2 Anéis/farmacologia , Ácidos Picolínicos/farmacologia , Inibidores de Proteases/farmacologia , Peptídeos beta-Amiloides/sangue , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Animais , Modelos Animais de Doenças , Cães , Compostos Heterocíclicos com 2 Anéis/farmacocinética , Compostos Heterocíclicos com 2 Anéis/uso terapêutico , Humanos , Camundongos , Ácidos Picolínicos/farmacocinética , Ácidos Picolínicos/uso terapêutico , Inibidores de Proteases/farmacocinética , Inibidores de Proteases/uso terapêutico
19.
Clin Appl Thromb Hemost ; 30: 10760296231224344, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38166421

RESUMO

We aimed to explore the relationship between pulmonary artery distensibility obtained from computed tomography pulmonary angiography (CTPA) and short-term adverse clinical outcomes in patients with acute pulmonary embolism (APE). We included patients who underwent retrospective electrocardiogram-gated CTPA and were subsequently diagnosed with APE. Patients were categorized into good and poor outcome groups based on short-term clinical outcomes. Pulmonary artery distensibility (AD), right ventricle/left ventricle (RV/LV) ratio, and pulmonary artery obstruction index (PAOI) were measured, and the receiver operating characteristic curves were constructed. Sixty-four patients with APE (good outcome, 46; poor outcome, 18) were enrolled. AD, RV/LV ratio, and PAOI differed significantly between groups (P < 0.05). Pulmonary artery AD in the good outcome group was greater than that in the poor outcome group (P < 0.001). The poor outcome group exhibited a higher RV/LV ratio and PAOI than the good outcome group (P < 0.05). AD and PAOI were independent predictors of adverse clinical outcomes. Areas under the curve for AD and PAOI were 0.860 (95% confidence interval [CI]: 0.750-0.934) and 0.675 (95%CI: 0.546-0.786), and the combined curve of the AD and RV/LV ratio was 0.906 (95%CI: 0.806-0.965). The calibration curve showed a combined curve superior to the other curves. The decision curve showed high clinical application value of the combined curve. Retrospective electrocardiogram-gated CTPA-derived AD could serve as an indicator for predicting short-term adverse clinical outcomes in APE. Combining AD and PAOI has a high predictive value for short-term adverse clinical outcomes.


Assuntos
Hominidae , Embolia Pulmonar , Humanos , Animais , Artéria Pulmonar , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Doença Aguda
20.
Adv Sci (Weinh) ; : e2407766, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39377200

RESUMO

Coronavirus 3C-like protease (CoV 3CLpro) is essential for viral replication, providing an attractive target for monitoring the evolution of CoV and developing anti-CoV drugs. Here, the substrate-binding modes of 3CLpros from four CoV genera are analyzed and found that the S2 pocket in 3CLpro is highly conserved within each genus but differs between genera. Functionally, the S2 pocket, in conjunction with S4 and S1' pockets, governs the genus-specific substrate selectivity of 3CLpro. Resurrected ancestral 3CLpros from four CoV genera validate the genus-specific divergence of S2 pocket. Drawing upon the genus-specific S2 pocket as evolutionary marker, eight newly identified 3CLpros uncover the ancestral state of modern 3CLpro and elucidate the possible evolutionary process for CoV. It is also demonstrated that the S2 pocket is highly correlated with the genus-specific inhibitory potency of PF-07321332 (an FDA-approved drug against COVID-19) on different CoV 3CLpros. This study on 3CLpro provides novel insights to inform evolutionary mechanisms for CoV and develop genera-specific or broad-spectrum drugs against CoVs.

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