Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.477
Filtrar
1.
Artigo em Inglês | MEDLINE | ID: mdl-38988153

RESUMO

BACKGROUND: The incidence of CRC has increased worldwide over the past decade. The statistics report from WHO highlights the increased severity and fatality rate of CRC among the populations. Wnt/ß-catenin is recognized as the resource for cell regeneration and cancer signaling pathways driven by frizzled receptor cofactors. Aberrant regulation of Wnt/ß- catenin suppression is an important challenge in treating CRC management. AIMS AND OBJECTIVE: The SFRP1 comprises a cysteine-rich region that is homologous to the putative Wnt-binding sites of Frizzled proteins, with the potential to impede and alter the cascade of Wnt signaling. Indirect regulation, like targeting Wnt antagonist SFRP1, is an alternative strategy to suppress the cancer signals by enhancing the apoptotic activity. Hence, this study aimed to approach the SFRP1 protein as a therapeutic target to inhibit Wnt signaling in colorectal cancer. Further, it aimed to identify the lead compounds against the SFRP1 protein, which inhibit the oncogenic expression of CRC, which might be possible using computational approaches, recognizing the importance of the SFRP1 protein role in CRC. METHODS: The homology-modeled SFRP1 structure was refined, and virtual screening was performed against the anti-cancer drugs and natural drug databases to find the best hit molecules. The molecular docking, MD, and MMGBSA analysis confirmed the firm binding of SFRP1 complexes to identify the potent CRC inhibitors. RESULTS: The amino acid residues Arg5, Arg11, Ala13, Lys 245, Lys274, Phe147, Pro99, and Ser277 are essential for ligand binding and show similar interactions for SFRP1 complexes. The ADME/T profile for top hits is acceptable in range and obtains the drug-likeness property. The 100ns run for MD simulation confirms the stability of protein complexes. CONCLUSION: Overall, the findings of this study reveal that the lead compounds screened are capable of inhibiting SFRP1 against CRC. Targeting SFRP1 paves the way for new platforms in the field of cancer and the therapeutic sector for new approachable finds.

2.
FEMS Microbiol Lett ; 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39013605

RESUMO

BACKGROUND: With an exponential growth in biological data and computing power, familiarity with bioinformatics has become a demanding and popular skill set both in academia and industry. There is a need to increase students' competencies to be able to take on bioinformatic careers, to get them familiarized with scientific professions in data science and the academic training required to pursue them, in a field where demand outweighs the supply. METHODS: Here we implemented a set of bioinformatic activities into a protein structure and function course of a graduate program. Concisely, students were given hands-on opportunities to explore the bioinformatics-based analyses of biomolecular data and structural biology via a semester-long case study structured as inquiry-based bioinformatics exercises. Towards the end of the term, the students also designed and presented an assignment project that allowed them to document the unknown protein that they identified using bioinformatic knowledge during the term. RESULTS: The post-module survey responses and students' performances in the lab module imply that it furthered an in-depth knowledge of bioinformatics. Despite having not much prior knowledge of bioinformatics prior to taking this module students indicated positive feedback. CONCLUSION: The students got familiar with cross-indexed databases that interlink important data about proteins, enzymes as well as genes. The essential skillsets honed by this research-based bioinformatic pedagogical approach will empower students to be able to leverage this knowledge for their future endeavours in the bioinformatics field.

3.
Mol Divers ; 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39043911

RESUMO

The excessive activation of the monkeypox virus (MPXV-Congo_8-156) is linked to various skin and respiratory disorders such as rashes, fluid-filled blisters, swollen lymph nodes and encephalitis (inflammation of the brain), highlighting MPXV-Congo_8-156 as a promising target for drug intervention. Despite the effectiveness of Cidofovir, in inhibiting MPXV activity, its limited ability to penetrate the skin and its strong side effects restrict its application. To address this challenge, we screened 500 compounds capable of penetrating the skin and gastrointestinal tract to identify potent MPXV inhibitors. Various characterization schemes and structural models of MPXV-Congo_8-156 were explored with bioinformatics tools like PROTPARAM, SOPMA, SWISS-MODEL and PROCHECK. Using molecular docking in PyRx, we evaluated the binding affinities of these compounds with MPXV-Congo_8-156 and identified the top five candidates ranging from - 9.2 to - 8.8 kcal/mol. ADMET analysis indicated that all five compounds were safer alternatives, showing no AMES toxicity or carcinogenicity in toxicological assessments. Molecular dynamics (MD) simulations, conducted for 100 ns each, confirmed the docking interactions of the top five compounds alongside the control (Cidofovir), validating their potential as MPXV inhibitors. The compounds with PubChem CID numbers 4061636, 4422538, 3583576, 4856107 and 4800629 demonstrated strong support in terms of root-mean-square deviation (RMSD), root-mean-square fluctuation (RMSF), radius of gyration (Rg), solvent-accessible surface area (SASA) value, hydrogen bond analysis, and Molecular Mechanics Poisson-Boltzmann Surface Area (MM-PBSA) analysis. Thus, our investigation identified these five compounds as promising inhibitors of MPXV, offering potential therapeutic avenues. However, further in vivo studies are necessary to validate our findings.

4.
Mol Inform ; : e202400046, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39046372

RESUMO

FFA4 has gained interest in recent years since its deorphanization in 2005 and the characterization of the Free Fatty Acids receptors family for their therapeutic potential in metabolic disorders. The expression of FFA4 (also known as GPR120) in numerous organs throughout the human body makes this receptor a highly potent target, particularly in fat sensing and diet preference. This offers an attractive approach to tackle obesity and related metabolic diseases. Recent cryo-EM structures of the receptor have provided valuable information for a potential active state although the previous studies of FFA4 presented diverging information. We performed molecular docking and molecular dynamics simulations of four agonist ligands, TUG-891, Linoleic acid, α-Linolenic acid, and Oleic acid, based on a homology model. Our simulations, which accumulated a total of 2 µs of simulation, highlighted two binding hotspots at Arg992.64 and Lys293 (ECL3). The results indicate that the residues are located in separate areas of the binding pocket and interact with various types of ligands, implying different potential active states of FFA4 and a highly adaptable binding intra-receptor pocket. This article proposes additional structural characteristics and mechanisms for agonist binding that complement the experimental structures.

5.
Heliyon ; 10(13): e33860, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39027572

RESUMO

Primary Sjögren's Syndrome (pSS) is a systemic autoimmune disease that leads to reduced saliva production, primarily affecting women due to estrogen deficiency. The estrogen receptor α (ERα) plays a crucial role in mediating the expression of the aquaporin 5 (AQP5) gene through the estrogen response element-dependent signaling pathway, making ERα a key drug target for pSS. Several flavonoids have been reported to have the potential to treat pSS. This study aimed to screen and compare flavonoids binding to ERα using AutoDock, providing a basis for treating pSS with flavonoids. The estrogenic potential of six representative flavonoids was examined in this study. Molecular docking revealed that the binding energy of all six flavonoids to ERα was less than -5.6 kcal/mol. Apigenin, naringenin, and daidzein were the top three flavonoids with even lower binding energies of -7.8, -8.09, and -8.59 kcal/mol, respectively. Similar to the positive control estradiol, apigenin, naringenin, and daidzein showed hydrogen bond interactions with GLU353, GLY521, and HIS524 at the active site. The results of luciferase reporter assays demonstrated that apigenin, naringenin, and daidzein significantly enhanced the transcription of estrogen receptor element (ERE) in the PGL3/AQP5 promoter. Furthermore, molecular dynamics simulations using GROMACS for a time scale of 100 ns revealed relatively stable binding of apigenin-ERα, naringenin-ERα, and daidzein-ERα. Mechanistically, homology modeling indicated that GLU353, GLY521, and HIS524 were the key residues of ERα exerting an estrogenic effect. The therapeutic effect of apigenin on dry mouth in pSS models was further validated. In conclusion, these results indicate the estrogenic and pSS therapeutic potential of apigenin, naringenin, and daidzein.

6.
Front Microbiol ; 15: 1410968, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38873149

RESUMO

Introduction: Sweet sorghum juice is a typical production feedstock for natural, eco-friendly sweeteners and beverages. Clostridium tyrobutyricum is one of the widely used microorganisms in the food industry, and its principal product, bio-butyric acid is an important food additive. There are no published reports of Clostridium tyrobutyricum producing butyric acid using SSJ as the sole substrate without adding exogenous substances, which could reach a food-additive grade. This study focuses on tailoring a cost-effective, safe, and sustainable process and strategy for their production and application. Methods: This study modeled the enzymolysis of non-reducing sugars via the first/second-order kinetics and added food-grade diatomite to the hydrolysate. Qualitative and quantitative analysis were performed using high-performance liquid chromatography, gas chromatography-mass spectrometer, full-scale laser diffraction method, ultra-performance liquid chromatography-tandem mass spectrometry, the cell double-staining assay, transmission electron microscopy, and Oxford nanopore technology sequencing. Quantitative real-time polymerase chain reaction, pathway and process enrichment analysis, and homology modeling were conducted for mutant genes. Results: The treated sweet sorghum juice showed promising results, containing 70.60 g/L glucose and 63.09 g/L fructose, with a sucrose hydrolysis rate of 98.29% and a minimal sucrose loss rate of 0.87%. Furthermore, 99.62% of the colloidal particles and 82.13% of the starch particles were removed, and the concentrations of hazardous substances were effectively reduced. A food microorganism Clostridium tyrobutyricum TGL-A236 with deep utilization value was developed, which showed superior performance by converting 30.65% glucose and 37.22% fructose to 24.1364 g/L bio-butyric acid in a treated sweet sorghum juice (1:1 dilution) fermentation broth. This titer was 2.12 times higher than that of the original strain, with a butyric acid selectivity of 86.36%. Finally, the Genome atlas view, Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and evolutionary genealogy of genes: Non-supervised Orthologous (eggNOG) functional annotations, three-dimensional structure and protein cavity prediction of five non-synonymous variant genes were obtained. Conclusion: This study not only includes a systematic process flow and in-depth elucidation of relevant mechanisms but also provides a new strategy for green processing of food raw materials, improving food microbial performance, and ensuring the safe production of food additives.

7.
Plants (Basel) ; 13(12)2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38931142

RESUMO

Computer-aided design usually gives inspirations and has become a vital strategy to develop novel pesticides through reconstructing natural lead compounds. Patulin, an unsaturated heterocyclic lactone mycotoxin, is a new natural PSII inhibitor and shows significant herbicidal activity to various weeds. However, some evidence, especially the health concern, prevents it from developing as a bioherbicide. In this work, molecular docking and toxicity risk prediction are combined to construct interaction models between the ligand and acceptor, and design and screen novel derivatives. Based on the analysis of a constructed patulin-Arabidopsis D1 protein docking model, in total, 81 derivatives are designed and ranked according to quantitative estimates of drug-likeness (QED) values and free energies. Among the newly designed derivatives, forty-five derivatives with better affinities than patulin are screened to further evaluate their toxicology. Finally, it is indicated that four patulin derivatives, D3, D6, D34, and D67, with higher binding affinity but lower toxicity than patulin have a great potential to develop as new herbicides with improved potency.

8.
Platelets ; 35(1): 2359028, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38832545

RESUMO

The purpose of this study is to investigate the molecular interactions and potential therapeutic uses of Eltrombopag (EPAG), a small molecule that activates the cMPL receptor. EPAG has been found to be effective in increasing platelet levels and alleviating thrombocytopenia. We utilized computational techniques to predict and confirm the complex formed by the ligand (EPAG) and the Thrombopoietin receptor (TPO-R) cMPL, elucidating the role of RAS, JAK-2, STAT-3, and other essential elements for downstream signaling. Molecular dynamics (MD) simulations were employed to evaluate the stability of the ligand across specific proteins, showing favorable characteristics. For the first time, we examined the presence of TPO-R in human umbilical cord mesenchymal stem cells (hUCMSC) and human gingival mesenchymal stem cells (hGMSC) proliferation. Furthermore, treatment with EPAG demonstrated angiogenesis and vasculature formation of endothelial lineage derived from both MSCs. It also indicated the activation of critical factors such as RUNX-1, GFI-1b, VEGF-A, MYB, GOF-1, and FLI-1. Additional experiments confirmed that EPAG could be an ideal molecule for protecting against UVB radiation damage, as gene expression (JAK-2, ERK-2, MCL-1, NFkB, and STAT-3) and protein CD90/cMPL analysis showed TPO-R activation in both hUCMSC and hGMSC. Overall, EPAG exhibits significant potential in treating radiation damage and mitigating the side effects of radiotherapy, warranting further clinical exploration.


What is the context?● Chemotherapy, radiation treatment, or immunological disorders can cause a decrease in platelet count (thrombocytopenia) or decrease all blood cell types (pancytopenia) in the bone marrow. This can make it challenging to choose the appropriate cancer treatment plan.● Eltrombopag (EPAG) is an oral non-peptide thrombopoietin (TPO) mimetic that activates the cMPL receptor in the body. This activation leads to cell differentiation and proliferation, stimulating platelet production and reducing thrombocytopenia. The cMPL receptor is present in liver cells, megakaryocytes, and hematopoietic cells. However, its effects on stem cell proliferation and differentiation are not entirely understood.What is the new?● This study delves into the molecular interactions and therapeutic applications of EPAG, a small molecule that activates cMPL (TPO-R).● The study offers a comprehensive analysis of the ligand-receptor complex formation, including an examination of downstream signaling elements. Furthermore, molecular dynamics simulations demonstrate the stability of the ligand when interacting with targeted proteins.● The research investigates the presence of TPO-R on stem cell-derived endothelial cells, shedding insight into the ability of EPAG TPO-mimetic to promote angiogenesis and vasculature formation.● The study revealed that EPAG has the potential to protect against UVB-induced radiation damage and stimulate stem cell growth.What is the implications?The study emphasizes the potential of EPAG as a promising option for addressing radiation injury and minimizing the adverse effects of radiotherapy. It could revolutionize treatments not only for thrombocytopenia but also for enhancing the growth of stem cells. Furthermore, the research deepens our understanding of EPAG's molecular mechanisms, providing valuable insights for developing future drugs and therapeutic approaches for cell therapy to treat radiation damage.


Assuntos
Benzoatos , Pirazóis , Receptores de Trombopoetina , Humanos , Pirazóis/farmacologia , Benzoatos/farmacologia , Receptores de Trombopoetina/metabolismo , Hidrazonas/farmacologia , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Hidrazinas/farmacologia , Hidrazinas/uso terapêutico , Simulação de Dinâmica Molecular , Angiogênese
9.
Food Microbiol ; 122: 104535, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38839215

RESUMO

A promising strategy to control bacterial diseases involves using Quorum Sensing Inhibitor (QSI) compounds. This study aimed to evaluate the potential of Falcaria vulgaris plant extract to combat the phytopathogenic Pectobacterium carotovorum subsp. carotovorum (Pcc) via its QSI activity. Using biosensors and Minimum Inhibitory Concentration (MIC) assays, the QSI and antimicrobial aspects of the extract were assessed. Furthermore, the effect of the extract on the reduction of tuber maceration in potatoes was examined. Subsequently, homology modeling based on LasR was conducted to analyze interactions between ligand 3-oxo-C8-AHL, and ExpR2 protein. Docking studies were performed on all extract compounds identified via Gas Chromatography-Mass Spectrometry (GC-MS) analysis. The extract effectively reduced maceration at sub-MIC concentrations across various pathogenic strains. Furthermore, Cyclopentadecanone, 2-hydroxy, showed more negative docking energy than the native ligand. Z,E-2,13-Octadecadien-1-ol showed energy equivalence to the native ligand. Additionally, this plant included certain compounds or their analogs that had previously been discovered as QSI compounds. These compounds included oleic acid, n-Hexadecanoic acid, cytidine, and linoleic acid, and they had energies that were comparable to that of the native ligand. In conclusion, the remarkable QSI property showed by this plant is likely attributed to a combination of compounds possessing this characteristic.


Assuntos
Antibacterianos , Simulação de Acoplamento Molecular , Pectobacterium carotovorum , Extratos Vegetais , Percepção de Quorum , Percepção de Quorum/efeitos dos fármacos , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Pectobacterium carotovorum/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Testes de Sensibilidade Microbiana , Solanum tuberosum/microbiologia , Solanum tuberosum/química , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle
10.
Front Pharmacol ; 15: 1387629, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38846093

RESUMO

Despite continuous efforts to develop safer and efficient medications, malaria remains a major threat posing great challenges for new drug discovery. The emerging drug resistance, increased toxicities, and impoverished pharmacokinetic profiles exhibited by conventional drugs have hindered the search for new entities. Plasmepsins, a group of Plasmodium-specific, aspartic acid protease enzymes, are involved in many key aspects of parasite biology, and this makes them interesting targets for antimalarial chemotherapy. Among different isoforms, PlmIX serves as an unexplored antimalarial drug target that plays a crucial role along with PlmV and X in the parasite's survival by digesting hemoglobin in the host's erythrocytes. In this study, fragment-based virtual screening was performed by modeling the three-dimensional structure of PlmIX and predicting its ligand-binding pocket by using the Sitemap tool. Screening identified the fragments with the XP docking score ≤ -3 kcal/mol from the OTAVA General Fragment Library (≈16,397 fragments), and the selected fragments were chosen for ligand breeding. The resulting ligands (≈69,858 ligands) were subsequently subjected to filtering based on the QikProp properties along with carcinogenicity testing performed using CarcinoPred-EL and then docked in the SP (≈14,078 ligands) as well as XP mode (≈3,104 ligands), and compared with that of control ligands 49C and I0L. The top-ranked ligands were taken further for the calculation of the free energy of binding using Prime MM-GBSA. Overall, a total of six complexes were taken further for MD simulation studies performed at 100 ns to attain a better understanding of the binding mechanisms, and compounds 3 and 4 were found to be the most efficient ones in silico. The analysis of compound 3 revealed that the carbonyl group present in position 1 on the isoindoline moiety (Arg554) was responsible for inhibitory activity against PlmIX. However, the analysis of compound 4 revealed that the amide linkage sandwiched between the phenyl ring and isoquinoline moiety (Lys555 and Ser226) as well as carbonyl oxygen of the carbamoyl group present at position 2 of the pyrazole ring (Gln222) were responsible for PlmIX inhibitory activity, owing to their crucial interactions with key amino acid residues.

11.
Int J Biol Macromol ; 271(Pt 1): 132434, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38788879

RESUMO

The aim of this study was to improve the inhibitory resistance of xylanase FgXyn11C from Fusarium graminearum to XIP in cereal flour. Site saturation mutagenesis was performed using computer-aided redesign. Firstly, based on multiple primary structure alignments, the amino acid residues in the active site architecture were identified, and specific residue T144 in the thumb region of FgXyn11C was selected for site-saturation mutagenesis. After screening, FgXyn11CT144F was selected as the best mutant, as it displayed the highest enzymatic activity and resistance simultaneously compared to other mutants. The specific activity of FgXyn11CT144F was 208.8 U/mg and it exhibited complete resistance to SyXIP-I. Compared with the wild-type, FgXyn11CT144F displayed similar activity and the most resistant against SyXIP-I. The optimal temperature and pH of the wild-type and purified FgXyn11CT144F were similar at pH 5.0 and 30 °C. Our findings provided preliminary insight into how the specific residue at position 144 in the thumb region of FgXyn11C influenced the enzymatic properties and interacted with SyXIP-I. The inhibition sensitivity of FgXyn11C was reduced through directed evolution, leading to creation of the mutant enzyme FgXyn11CT144F. The FgXyn11CT144F resistance to SyXIP-I has potential application and can also provide references for engineering other resistant xylanases of the GHF11.


Assuntos
Endo-1,4-beta-Xilanases , Fusarium , Mutagênese Sítio-Dirigida , Fusarium/enzimologia , Fusarium/efeitos dos fármacos , Fusarium/genética , Endo-1,4-beta-Xilanases/genética , Endo-1,4-beta-Xilanases/química , Endo-1,4-beta-Xilanases/metabolismo , Endo-1,4-beta-Xilanases/antagonistas & inibidores , Domínio Catalítico , Modelos Moleculares , Concentração de Íons de Hidrogênio , Sequência de Aminoácidos , Temperatura
12.
Curr Aging Sci ; 2024 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-38778612

RESUMO

BACKGROUND: X-linked mutations are highly important in clinical diagnosis, and at least 533 disorders are related to the genes located on the X chromosome. CASE PRESENTATION: A 21-year-old Caucasian woman with a 24-year-old Caucasian man as her fiancé referred Clinical genetic lab for premarital genetic counseling (carrier screening). None of them had any abnormal manifestations. Following genetic counseling, Whole Exome Sequencing (WES) test performed to find the possible pathogenic mutations. Also, after drawing the couple's pedigree, candidate mutations were examined in the woman's parents as well as her uncles. Additionally, in silico investigations were performed through SWISS-MODEL, MolProbity, ProSA, Py- Mol, and FATCAT tools. The most important mutation diagnosed in the woman (R1362Q in the 35th exon of CACNA1F), was observed in her mother and her two uncles. The mutation was also screened in both her father and her fiancé, but they had no mutations. After medical examinations of carriers, there was no sign of any eye impairment. Other mutations were TCTN2 (c.1613-2A>G), TARS (p.K319E), SPEG (p.E3020K), CPS1 (p.A1180V), MYO3A (p.I736M), NNT (p.R968Q), MED23 (p.K406T). Bioinformatics analyses indicated no alteration in the mutant structure of CACNA1F (Q1362) compared with the normal structure (R1362). CONCLUSION: Conclusively, the current study emphasizes the non-pathogenic effect of missense mutation R1362Q in the 35th exon of CACNA1F in association with ocular diseases. This will ensure the reports of this mutation as healthy instead of uncertain in the literature and databanks.

13.
Heliyon ; 10(6): e27602, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38509977

RESUMO

Leishmaniasis is one of the top 10 neglected tropical diseases. Globally, it impacts more than 12 million individuals. In light of the absence of a safer, affordable treatment for the Leishmaniasis, along with therapeutic failures and drug resistance, novel therapeutic strategies are necessary to discover new drugs. Treatment would benefit by concentrating on the precise targets that are crucial for the parasite to survive. A target that aids in the organism's survival under oxidative stress is trypanothione synthetase (TyS), which is a component of the trypanothione pathway in Leishmania spp. To find potential TyS inhibitors for the purpose of discovering novel antileishmanial drugs, we used a virtual screening strategy. Using the Glide module of Schrodinger-suite 2023, an FDA-approved library containing 2000 drugs from the ZINC-15 database was screened against the TyS. Dostinex, raloxifene, and formoterol showed good docking scores of -10.568 kcal/mol, -10.446 kcal/mol, and -56.21 kcal/mol, as well as good binding energies of -70.41 kcal/mol, -56.21 kcal/mol, and -64.15 kcal/mol respectively. The stability of the ligand-protein complexes was assessed further with the help of Desmond to execute a 100-ns molecular dynamics simulation. The Prime module was utilised to perform post-MM/GBSA analysis on these three molecules along with the toxicity profiling using Protox II web server. This study suggests that dostinex, formoterol, and raloxifene may act as effective inhibitors of the TyS receptor which could be used as novel antileishmanial agents for the therapeutic applications. Thorough preclinical studies are necessary to confirm the identified compounds chemotherapeutic qualities.

14.
Front Mol Biosci ; 11: 1345158, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38545419

RESUMO

Prokaryotic deacetylases are classified into nicotinamide adenine dinucleotide (NAD+)-dependent sirtuins and Zn2+-dependent deacetylases. NAD+ is a coenzyme for redox reactions, thus serving as an essential component for energy metabolism. The NAD+-dependent deacetylase domain is quite conserved and well characterized across bacterial species like CobB in Escherichia coli and Salmonella, Rv1151c in Mycobacterium, and SirtN in Bacillus subtilis. E. coli CobB is the only bacterial deacetylase with a known crystal structure (PDB ID: 1S5P), which has 91% sequence similarity with Salmonella CobB (SeCobB). Salmonella encodes two CobB isoforms, SeCobBS and SeCobBL, with a difference of 37 amino acids in its N-terminal domain (NTD). The hydrophobic nature of NTD leads to the stable oligomerization of SeCobBL. The homology modeling-based predicted structure of SeCobB showed the presence of a zinc-binding motif of unknown function. Tryptophan fluorescence quenching induced by ZnCl2 showed that Zn2+ has a weak interaction with SeCobBS but higher binding affinity toward SeCobBL, which clearly demonstrated the crucial role of NTD in Zn2+ binding. In the presence of Zn2+, both isoforms had significantly reduced thermal stability, and a greater effect was observed on SeCobBL. Dynamic light scattering (DLS) studies reflected a ninefold increase in the scattering intensity of SeCobBL upon ZnCl2 addition in contrast to an ∼onefold change in the case of SeCobBS, indicating that the Zn2+ interaction leads to the formation of large particles of SeCobBL. An in vitro lysine deacetylase assay showed that SeCobB deacetylated mammalian histones, which can be inhibited in the presence of 0.25-1.00 mM ZnCl2. Taken together, our data conclusively showed that Zn2+ strongly binds to SeCobBL through the NTD that drastically alters its stability, oligomeric status, and enzymatic activity in vitro.

15.
Food Res Int ; 182: 114139, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38519171

RESUMO

The previously obtained chicken-derived umami peptides in the laboratory were evaluated for their saltiness-enhancing effect by sensory evaluation and S-curve, and the results revealed that peptides TPPKID, PKESEKPN, TEDWGR, LPLQDAH, NEFGYSNR, and LPLQD had significant saltiness-enhancing effects. In the binary solution system with salt, the ratio of the experimental detection threshold (129.17 mg/L) to the theoretical detection threshold (274.43 mg/L) of NEFGYSNR was 0.47, which had a synergistic saltiness-enhancing effect with salt. The model of transmembrane channel-like protein 4 (TMC4) channel protein was constructed by homology modeling, which had a 10-fold transmembrane structure and was well evaluated. Molecular docking and frontier molecular orbitals showed that the main active sites of TMC4 were Lys 471, Met 379, Cys 475, Gln 377, and Pro 380, and the main active sites of NEFGYSNR were Tyr, Ser and Asn. This study may provide a theoretical reference for low-sodium diets.


Assuntos
Galinhas , Peptídeos , Animais , Simulação de Acoplamento Molecular , Peptídeos/química , Proteínas , Cloreto de Sódio na Dieta
16.
Biol Pharm Bull ; 47(3): 580-590, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38432913

RESUMO

There are 48 nuclear receptors in the human genome, and many members of this superfamily have been implicated in human diseases. The NR4A nuclear receptor family consisting of three members, NR4A1, NR4A2, and NR4A3 (formerly annotated as Nur77, Nurr1, and NOR1, respectively), are still orphan receptors but exert pathological effects on immune-related and neurological diseases. We previously reported that prostaglandin A1 (PGA1) and prostaglandin A2 (PGA2) are potent activators of NR4A3, which bind directly to the ligand-binding domain (LBD) of the receptor. Recently, the co-crystallographic structures of NR4A2-LBD bound to PGA1 and PGA2 were reported, followed by reports of the neuroprotective effects of these possible endogenous ligands in mouse models of Parkinson's disease. Based on these structures, we modeled the binding structures of the other two members (NR4A1 and NR4A3) with these potential endogenous ligands using a template-based modeling method, and reviewed the similarity and diversity of ligand-binding mechanisms in the nuclear receptor family.


Assuntos
Doença de Parkinson , Humanos , Animais , Camundongos , Ligantes , Modelos Animais de Doenças , Domínios Proteicos , Prostaglandinas
17.
Front Plant Sci ; 15: 1348815, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38455726

RESUMO

Introduction: Bromus japonicus is one of the most notorious agricultural weeds in China. The long-term use of ALS-inhibiting herbicides has led to rapid evolution of herbicide resistance in B. japonicus. B. japonicus population (BJ-R) surviving mesosulfuron-methyl treatment was collected from wheatland. Here, we aimed to confirm the resistance mechanisms in this putative resistant population. Methods: The dose-reponse tests were used to test the resistance level of the B. japonicus to ALS-inhibiting herbicides. Pretreatment with P450 and GST inhibitors and GST activity assays were used to determine whether P450 or GST was involved in the resistance of the BJ-R population. Sanger sequencing was used to analyse the ALS mutation of the BJ-R population. RT-qPCR was used to confirm the the expression levels of the ALS gene in mesosulfuron-methyl -resistant (BJ-R) and-susceptible (BJ-S) B. japonicus. An in vitro ALS activity assay was used to determine the ALS activity of the BJ-R and BJ-S populations. Homology modelling and docking were used to determine the binding energy of the BJ-R and BJ-S populations with ALS-inhibiting herbicides. Results: B. japonicus population (BJ-R) was confirmed to be 454- and 2.7-fold resistant to the SU herbicides mesosulfuron-methyl and nicosulfuron, and 7.3-, 2.3-, 1.1- and 10.8-fold resistant to the IMI herbicide imazamox, the TP herbicide penoxsulam, the PTB herbicide pyribenzoxim and the SCT herbicide flucarbazone-sodium, respectively, compared with its susceptible counterpart (BJ-S). Neither a P450 inhibitor nor a GST inhibitor could reverse the level of resistance to mesosulfuron-methyl in BJ-R. In addition, no significant differences in GST activity were found between the BJ-R and BJ-S. ALS gene sequencing revealed a Pro-197-Thr mutation in BJ-R, and the gene expression had no significant differences between the BJ-R and BJ-S. The ALS activity of BJ-R was 106-fold more tolerant to mesosulfuron-methyl than that of BJ-S. Molecular docking showed that the binding energy of the ALS active site and mesosulfuron-methyl was changed from -6.67 to -4.57 kcal mol-1 due to the mutation at position 197. Discussion: These results suggested that the Pro-197-Thr mutation was the main reason for the high resistance level of BJ-R to mesosulfuron-methyl. Unlike previous reports of the cross-resistance pattern conferred by this mutation, we firstly documented that the Pro-197-Thr mutation confers broad cross-resistance spectrums to ALS-inhibiting herbicides in B. japonicus.

18.
Pharmaceuticals (Basel) ; 17(3)2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38543166

RESUMO

Empirically, in Indonesia, the leaves of Cassia alata L. (candle bush or ketepeng cina) have been used as a topical antifungal agent. Malassezia furfur is a natural microorganism found in the human body. It is among the factors contributing to conditions such as pityriasis versicolor, a common, benign, superficial fungal infection of the skin that is closely associated with seborrheic dermatitis and dandruff. This study aimed to explore C. alata leaves, starting from determining antifungal activity against M. furfur and the identification of major compounds in the ethyl acetate and n-hexane fractions, and then we carried out molecular docking of the major compounds in the n-hexane fraction to lanosterol 14-alpha demethylase. The method was the disc diffusion technique to test antifungal activity, LC-MS/MS for major compound identification, and homology modeling through Swiss Models for molecular docking. The fractions of ethyl acetate and n-hexane extract showed concentration-dependent antifungal activity against M. furfur. The LCMS/MS analysis revealed five major compounds in the ethyl acetate and n-hexane fractions. The molecular docking demonstrated the highest binding affinity with stearidonic acid at -7.2 kcal/mol. It can be concluded that the compounds in the n-hexane fraction have antifungal activity against M. furfur, as supported by both in vitro and in silico studies.

19.
BMC Chem ; 18(1): 39, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38388460

RESUMO

Anti-cancer peptides (ACPs) are short peptides known for their ability to inhibit tumor cell proliferation, migration, and the formation of tumor blood vessels. In this study, we designed ACPs to target receptors often overexpressed in cancer using a systematic in silico approach. Three target receptors (CXCR1, DcR3, and OPG) were selected for their significant roles in cancer pathogenesis and tumor cell proliferation. Our peptide design strategy involved identifying interacting residues (IR) of these receptors, with their natural ligands serving as a reference for designing peptides specific to each receptor. The natural ligands of these receptors, including IL8 for CXCR1, TL1A for DcR3, and RANKL for OPG, were identified from the literature. Using the identified interacting residues (IR), we generated a peptide library through simple permutation and predicted the structure of each peptide. All peptides were analyzed using the web-based prediction server for Anticancer peptides, AntiCP. Docking simulations were then conducted to analyze the binding efficiencies of peptides with their respective target receptors, using VEGA ZZ and Chimera for interaction analysis. Our analysis identified HPKFIKELR as the interacting residues (IR) of CXCR-IL8. For DcR3, we utilized three domains from TL1A (TDSYPEP, TKEDKTF, LGLAFTK) as templates, along with two regions (SIKIPSS and PDQDATYP) from RANKL, to generate a library of peptide analogs. Subsequently, peptides for each receptor were shortlisted based on their predicted anticancer properties as determined by AntiCP and were subjected to docking analysis. After docking, peptides that exhibited the least binding energy were further analyzed for their detailed interaction with their respective receptors. Among these, peptides C9 (HPKFELY) and C7 (HPKFEWL) for CXCR1, peptides D6 (ADSYPQP) and D18 (AFSYPFP) for DcR3, and peptides P19 (PDTYPQDP) and p16 (PDQDATYP) for OPG, demonstrated the highest affinity and stronger interactions compared to the other peptides. Although in silico predictions indicated a favorable binding affinity of the designed peptides with target receptors, further experimental validation is essential to confirm their binding affinity, stability and pharmacokinetic characteristics.

20.
Pharmaceuticals (Basel) ; 17(2)2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38399478

RESUMO

Recent research has uncovered a promising approach to addressing the growing global health concern of obesity and related disorders. The inhibition of inositol hexakisphosphate kinase 1 (IP6K1) has emerged as a potential therapeutic strategy. This study employs multiple ligand-based in silico modeling techniques to investigate the structural requirements for benzisoxazole derivatives as IP6K1 inhibitors. Firstly, we developed linear 2D Quantitative Structure-Activity Relationship (2D-QSAR) models to ensure both their mechanistic interpretability and predictive accuracy. Then, ligand-based pharmacophore modeling was performed to identify the essential features responsible for the compounds' high activity. To gain insights into the 3D requirements for enhanced potency against the IP6K1 enzyme, we employed multiple alignment techniques to set up 3D-QSAR models. Given the absence of an available X-ray crystal structure for IP6K1, a reliable homology model for the enzyme was developed and structurally validated in order to perform structure-based analyses on the selected dataset compounds. Finally, molecular dynamic simulations, using the docked poses of these compounds, provided further insights. Our findings consistently supported the mechanistic interpretations derived from both ligand-based and structure-based analyses. This study offers valuable guidance on the design of novel IP6K1 inhibitors. Importantly, our work exclusively relies on non-commercial software packages, ensuring accessibility for reproducing the reported models.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...