RESUMEN
When an epidemic started in the Chinese city of Wuhan in December 2019, coronavirus was identified as the cause. Infection by the virus occurs through the interaction of viral S protein with the hosts' angiotensin-converting enzyme 2. By leveraging resources such as the DrugBank database and bioinformatics techniques, ligands with potential activity against the SARS-CoV-2 spike protein were designed and identified in this investigation. The FTMap server and the Molegro software were used to determine the active site of the Spike-ACE2 protein's crystal structure. Virtual screening was performed using a pharmacophore model obtained from antiparasitic drugs, obtaining 2000 molecules from molport®. The ADME/Tox profiles were used to identify the most promising compounds with desirable drug characteristics. The binding affinity investigation was then conducted with selected candidates. A molecular docking study showed five structures with better binding affinity than hydroxychloroquine. Ligand_003 showed a binding affinity of -8.645 kcal·mol-1, which was considered an optimal value for the study. The values presented by ligand_033, ligand_013, ligand_044, and ligand_080 meet the profile of novel drugs. To choose compounds with favorable potential for synthesis, synthetic accessibility studies and similarity analyses were carried out. Molecular dynamics and theoretical IC50 values (ranging from 0.459 to 2.371 µM) demonstrate that these candidates are promising for further tests. Chemical descriptors showed that the candidates had strong molecule stability. Theoretical analyses here show that these molecules have potential as SARS-CoV-2 antivirals and therefore warrant further investigation.
Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Simulación del Acoplamiento Molecular , Enzima Convertidora de Angiotensina 2 , Ligandos , Simulación de Dinámica Molecular , Antivirales/farmacología , Antivirales/química , Unión ProteicaRESUMEN
The development of novel scaffolds that can increase the effectiveness, safety, and convenience of medication therapy using drug conjugates is a promising strategy. As a result, drug conjugates are an active area of research and development in medicinal chemistry. This research demonstrates acetamide-sulfonamide scaffold preparation after conjugation of ibuprofen and flurbiprofen with sulfa drugs, and these scaffolds were then screened for urease inhibition. The newly designed conjugates were confirmed by spectroscopic techniques such as IR, 1HNMR, 13CNMR, and elemental analysis. Ibuprofen conjugated with sulfathiazole, flurbiprofen conjugated with sulfadiazine, and sulfamethoxazole were found to be potent and demonstrated a competitive mode of urease inhibition, with IC50 (µM) values of 9.95 ± 0.14, 16.74 ± 0.23, and 13.39 ± 0.11, respectively, and urease inhibition of 90.6, 84.1, and 86.1% respectively. Ibuprofen conjugated with sulfanilamide, sulfamerazine, and sulfacetamide, whereas flurbiprofen conjugated with sulfamerazine, and sulfacetamide exhibited a mixed mode of urease inhibition. Moreover, through molecular docking experiments, the urease receptor-binding mechanisms of competitive inhibitors were anticipated, and stability analysis through MD simulations showed that these compounds made stable complexes with the respective targets and that no conformational changes occurred during the simulation. The findings demonstrate that conjugates of approved therapeutic molecules may result in the development of novel classes of pharmacological agents for the treatment of various pathological conditions involving the urease enzyme.
Asunto(s)
Flurbiprofeno , Simulación del Acoplamiento Molecular , Flurbiprofeno/farmacología , Ibuprofeno/farmacología , Inhibidores Enzimáticos/farmacología , Sulfacetamida , Cinética , Ureasa , Sulfamerazina , Canavalia , Relación Estructura-Actividad , Sulfanilamida , Sulfonamidas/farmacología , Estructura MolecularRESUMEN
Survivin (IAP proteins) is considered as a significant target for anticancer drug research owing to its upregulation in tumor cells to mediate resistance to apoptotic stimulus. The current study aimed to investigate phytochemicals as inhibitors of survivin with caspases to reactivate the functioning of caspases through molecular docking. The compounds namely 2(R), 4(R)-dihydroxypyrrolidine, 4-hydroxy-2-(4-methoxyphenyl)-1,1-dioxo-3,4-dihydrothieno[3,2-e]thiazine-6-sulfonamide, 2,3-Diketo-L-gulonic acid, (3-hydroxy-2-octadeca-9,12-dienoyloxypropyl) octadecanoate, 2-[[4-[[4-[(4-formamido-1-methylimidazole-2-carbonyl)amino]-1-methylimidazole-2-carbonyl]amino]-1-methylimidazole-2-carbonyl]amino]ethyl-dimethylazanium, Picolinic acid and (2-Hydroxy-5-nitrophenyl) dihydrogen phosphate successfully bind inside the pocket of survivin. ADMETsar was used to evaluate the anticancer potential of selected compounds. These compounds can be proposed as effective inhibitors, disrupting the survivin-caspases interaction and reactivating the caspases function of apoptosis. The study might facilitate the development of cost-effective and natural drugs against cancer. However, further validation is essential for confirmation of its drug efficacy and bio-compatibility.
Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Ensayos de Selección de Medicamentos Antitumorales/métodos , Fitoquímicos/farmacología , Survivin/antagonistas & inhibidores , Survivin/química , Antineoplásicos Fitogénicos/farmacocinética , Antineoplásicos Fitogénicos/toxicidad , Caspasas/metabolismo , Simulación por Computador , Humanos , Simulación del Acoplamiento Molecular , Terapia Molecular Dirigida , Fitoquímicos/farmacocinética , Fitoquímicos/toxicidad , Conformación Proteica , Survivin/metabolismo , Distribución TisularRESUMEN
Nontuberculous mycobacteria (NTM) are widespread environmental organisms found in both natural and man-made settings, such as building plumbing, water distribution networks and hospital water systems. Their ubiquitous presence increases the risk of transmission, leading to a wide range of human infections, particularly in immunocompromised individuals. NTM primarily spreads through environmental exposures, such as inhaling aerosolized particles, ingesting contaminated food and introducing it into wounds. Hospital-associated outbreaks have been linked to contaminated medical devices and water systems. Furthermore, the rising global incidence, prevalence and isolation rates highlight the urgency of addressing NTM infections. Gaining a thorough insight into the sources and epidemiology of NTM infection is crucial for devising novel strategies to prevent and manage NTM transmission and infections.
Non-tuberculous mycobacteria (NTM) are environmental pathogens affecting humans and animals, with a substantial public health impact. These bacteria have been frequently identified in various natural and human-engineered settings, contributing to their potential transmission.
Asunto(s)
Infección Hospitalaria , Brotes de Enfermedades , Infecciones por Mycobacterium no Tuberculosas , Micobacterias no Tuberculosas , Humanos , Infecciones por Mycobacterium no Tuberculosas/epidemiología , Infecciones por Mycobacterium no Tuberculosas/transmisión , Infecciones por Mycobacterium no Tuberculosas/microbiología , Micobacterias no Tuberculosas/aislamiento & purificación , Infección Hospitalaria/epidemiología , Infección Hospitalaria/transmisión , Infección Hospitalaria/microbiología , HospitalesRESUMEN
CONTEXT: Epidermal growth factor receptor (EGFR), a member of the HER receptor family, is over expressed in various cancer cells. Using tumor-specific antibodies to deliver cytotoxic agents directly to the tumor cells is an effective treatment strategy. Targeted therapy by fusing anti-EGFR scFv with tumor-specific cytokines promises the emergence of a new era. METHODS: We designed a novel immuno-apoptotic fusion protein, anti-EGFR scFv-IL-24, consisting of a specific cancer cell targeting antibody and recombinant cytokine IL-24 to explore its anti-cancerous potential. Amino acid sequences of both anti-EGFR scFv and IL-24 were fused using a specific rigid linker. In silico characterization of the designed fusion protein like to predict the primary, secondary, physiochemical properties, quality, and structural validation using online bioinformatic tools. The newly designed fusion protein consists of 402 amino acids that showed good quality with a predicted value of 76.7% having 81.5% residues in the most favored region as predicted by ERRAT2 and Ramachandran plot analysis. Docking and simulation studies were performed using HDOCK and Desmond module of Schrodinger. All the parameters of quality, validity, interaction analysis, and stability suggested that the fused molecule is fully operational and functional. The results of the study support that the anti-EGFR scFv-IL-24 fused protein could be proved as a novel candidate to combat cancer.
Asunto(s)
Aminoácidos , Apoptosis , Secuencia de Aminoácidos , Biología Computacional , Simulación por ComputadorRESUMEN
PGAM1 plays a critical role in cancer cell metabolism through glycolysis and different biosynthesis pathways to promote cancer. It is generally known as a crucial target for treating pancreatic ductal adenocarcinoma, the deadliest known malignancy worldwide. In recent years different studies have been reported that strived to find inhibitory agents to target PGAM1, however, no validated inhibitor has been reported so far, and only a small number of different inhibitors have been reported with limited potency at the molecular level. Our in silico studies aimed to identify potential new PGAM1 inhibitors that could bind at the allosteric sites. At first, shape and feature-based models were generated and optimized by performing receiver operating characteristic (ROC) based enrichment studies. The best query model was then employed for performing shape, color, and electrostatics complementarity-based virtual screening of the ChemDiv database. The top two hundred and thirteen hits with greater than 1.2 TanimotoCombo score were selected and then subjected to structure-based molecular docking studies. The hits yielded better docking scores than reported compounds, were selected for subsequent structural similarity-based clustering analysis to select the best hits from each cluster. Molecular dynamics simulations and binding free energy calculations were performed to validate their plausible binding modes and their binding affinities with the PGAM1 enzyme. The results showed that these compounds were binding in the reported allosteric site of the enzyme and can serve as a good starting point to design better active selective scaffolds against PGAM1enzyme.
Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Simulación del Acoplamiento Molecular , Fosfoglicerato Mutasa/genética , Simulación de Dinámica MolecularRESUMEN
The peels extracted from various citrus species are major source of phenols, flavonoids and anti-microbial agents. The purpose of this study was a detailed investigation of the phytochemical and pharmacological character of the ethanolic (80%), methanolic and acetone extracts of the peel of local variants of orange (lemon, grape fruit, mousami, fruiter, and shikri malta). The extracts were studied to find out the total phenolic contents (TPC), and total flavonoids (TF) present. The antioxidant activities were assessed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging effect, and the reducing power was determined through free radical scavenging activity (FRAP) assays. The sensitivity of four bacterial strains to peels extracts was examined by applying the diffusion disc on agar medium method. It was found that ethanol was the best extracting agent for TPC and TF in fruit peels under study. The highest TPC (21.33 ± 0.06 mg GAE/g) was quantified in orange peels, whereas fruiter contained the lowest TPC (20.40 ± 0.03 mg GAE/g) in ethanolic extract. The highest amount of TF (2.02 ± 0.08 mg QE/g) was quantified in lemon peels, whereas shikri malta contained lowest quantity of TF (1.04 ± 0.02 mg QE/g). The highest free radical scavenging activity (93.1%) of DPPH was exhibited by lemon peels, whereas the least activity (78.6%) was shown by mousami peels. Ethanolic extract of orange peels demonstrated more reducing power while showing an absorption of 1.98, followed by methanolic (1.11) and acetone (0.81) extracts. The inhibition effect of methanolic extract of lemon peels (inhibition zone = 18 mm) against B. subtilis was considerable and comparable to that of ciprofloxacin. Gas chromatography/mass spectrometry (GC/MS) was used to detect the compounds in ethanolic extract and up to 14 compounds were detected. These compounds were also assessed for their docking scores. Plausible binding modes with polyphenol oxidase and four best compounds were selected for molecular dynamics (MD) simulation to analyze their structural stability with receptor.
RESUMEN
SARS-CoV-2 enters the host cell through the ACE2 receptor and replicates its genome using an RNA-Dependent RNA Polymerase (RDRP). The functional RDRP is released from pro-protein pp1ab by the proteolytic activity of Main protease (Mpro) which is encoded within the viral genome. Due to its vital role in proteolysis of viral polyprotein chains, it has become an attractive potential drug target. We employed a hierarchical virtual screening approach to identify small synthetic protease inhibitors. Statistically optimized molecular shape and color-based features (various functional groups) from co-crystal ligands were used to screen different databases through various scoring schemes. Then, the electrostatic complementarity of screened compounds was matched with the most active molecule to further reduce the hit molecules' size. Finally, five hundred eighty-seven molecules were docked in Mpro catalytic binding site, out of which 29 common best hits were selected based on Glide and FRED scores. Five best-fitting compounds in complex with Mpro were subjected to MD simulations to analyze their structural stability and binding affinities with Mpro using MM/GB(PB)SA models. Modeling results suggest that identified hits can act as the lead compounds for designing better active Mpro inhibitors to enhance the chemical space to combat COVID-19.Communicated by Ramaswamy H. Sarma.
Asunto(s)
COVID-19 , Humanos , SARS-CoV-2 , Sitios de Unión , Catálisis , Ligandos , ARN Polimerasa Dependiente del ARN , Simulación del Acoplamiento Molecular , Inhibidores de Proteasas/farmacologíaRESUMEN
Immunotherapy using checkpoint inhibitors blocks the checkpoint proteins (programmed cell death receptor-1; PD-1) from binding with their corresponding ligands (programmed cell death receptor ligand-1; PD-L1) to regulate cell signaling pathways. The marine environment holds a huge source of small molecules that are understudied which can be developed as an inhibitor. Hence, this study investigated the inhibitory effect of 19 algae-derived small molecules against PD-L1 by using molecular docking, absorption, distribution, metabolism, and elimination (ADME) properties and molecular dynamics simulations (MDS). The molecular docking revealed that the binding energy of the six best compounds ranges from -11.1 to -9.1 kcal/mol. Fucoxanthinol, in particular, has the strongest binding energy at -11.1 kcal/mol with three hydrogen bonds (ASN:63A, GLN:66A, and ASP:122A). Meanwhile, the MDS demonstrated that the ligands were strongly bound to the protein, indicating the stability of the complexes. In summary, the identified compounds are potential PD-L1 inhibitors in immunotherapy.Communicated by Ramaswamy H. Sarma.
RESUMEN
The search for novel drug scaffolds that can improve effectiveness and safety through drug conjugates is a promising approach. Consequently, drug conjugates constitute a dynamic field of study and advancement within medicinal chemistry. This research demonstrates the conjugation of diclofenac and mefenamic acid with sulfa drugs and their screening for urease inhibition. These conjugates' structural confirmation was performed using elemental analysis and spectroscopic methods, including IR, 1H NMR, and 13C NMR. Diclofenac conjugated with sulfanilamide (4), sulfacetamide (10), and mefenamic acid conjugated with sulfanilamide (12), and sulfamethoxazole (17) was found potent and demonstrated urease inhibition competitively, with IC50 (µM) values 3.59 ± 0.07, 5.49 ± 0.34, 7.92 ± 0.27, and 8.35 ± 0.26, respectively. Diclofenac conjugated with sulfathiazole (6), sulfamerazine (8), and sulfaguanidine (11), while mefenamic acid conjugated with sulfisoxazole (13), sulfathiazole (14), and sulfadiazine (15) exhibited a mixed mode of urease inhibition. The IC50 (µM) values were 16.19 ± 0.21, 9.50 ± 0.28, 4.35 ± 0.23, 15.86 ± 0.25, 14.80 ± 0.27, and 7.92 ± 0.27, respectively. Furthermore, molecular docking studies were employed to predict the binding pose of competitive inhibitors at the urease active site. These conjugates generated stable complexes with the urease protein observed through molecular dynamics (MD) simulations, where no conformational changes occurred throughout the simulations. These results highlight the potential for approved therapeutic molecule conjugates to give rise to new categories of pharmacological agents for urease inhibition. The structural similarity of sulfonamides with urea allows them to compete with urea for binding to the active site of the urease enzyme. Sulfonamides and nonsteroidal anti-inflammatory drugs (NSAIDs) can interact hydrophobically with the active site of the urease enzyme, which may disturb its structure and catalytic activity. Therefore, these conjugates may be helpful in the development of novel pharmacological agents for the treatment of a variety of illnesses in which the urease enzyme is involved.
RESUMEN
Derivative synthesis has been a crucial method for altering the effects of already-approved medications, especially to lessen adverse effects and enhance results. Making use of this multi-target approach, a series of naproxen-sulfa drug conjugates was designed and synthesized. The newly designed conjugates were confirmed by spectroscopic techniques like IR, 1HNMR, 13CNMR, and elemental analysis. The conjugates were screened for anti-inflammatory, urease, and cyclooxygenase-2 (COX-2) inhibition. Naproxen conjugated with sulfanilamide, sulfathiazole, and sulfaguanidine was found potent and showed a competitive mode of urease inhibition, with IC50 (µM) values 6.69 ± 0.11, 5.82 ± 0.28, 5.06 ± 0.29, respectively. When compared to other screened conjugates, the naproxen-sulfamethoxazole conjugation showed better anti-inflammatory action by inhibiting induced edema by 82.8%, which is comparable to the medication indomethacin (86.8% inhibition). Whereas it exhibited 75.4% inhibition of COX-2 at 10 µM concentration which is comparable with the reference drug (celecoxib, 77.1% inhibition). Moreover, the binding modes of competitive inhibitors with the urease and COX-2 receptor were predicted through molecular docking studies and their stability analysis through MD simulations showed that these compounds made stable complexes with the respective targets and there were no conformational changes that occurred during simulation. The obtained results showed that the conjugates of approved therapeutic molecules may lead to the development of novel types of pharmacological agents in the treatment of several pathological disorders where urease and COX-2 enzymes are involved.
RESUMEN
Curcumin is an extensively studied natural compound due to its extensive biological applications. However, there are some drawbacks linked to this compound such as poor absorption, low water-solubility, quick systemic elimination, fast metabolism, poor pharmacokinetics, low bioavailability, low penetration targeting efficacy and low stability. To overcome these drawbacks, curcumin is encapsulated in nano-carriers. In the current studies, we synthesized nanoparticles of curcumin without using nanocarriers by different methods such as nano-suspension (Cur-NSM), sonication (Cur-SM) and anti-solvent precipitation (Cur-ASP) to enhance the solubility of curcumin in water. The prepared nanoparticles were characterized by FTIR, SEM and XRD analysis. These curcumin nanoparticles were screened for their solubilities in water, DPPH scavenging, amylase, α-glucosidase and ß-glucosidase enzymatic activities. The particle size of nano-curcumin was found to be in the 47.4-98.7 nm range. The reduction in particle size of curcumin dramatically increases its solubility in water to 79.2 µg mL-1, whereas the solubility of curcumin is just 0.98 µg mL-1. Cur-ASP showed the highest free radical scavenging potential (48.84 ± 0.98%) which was comparable with standard BHT (50.48 ± 1.11%) at 75.0 µg mL-1. As well, Cur-ASP showed the highest inhibition of α-amylase (68.67 ± 1.02%), α-glucosidase (58.30 ± 0.52%), and ß-glucosidase (64.80 ± 0.43%) at 100 µg mL-1 which is comparable with standard drug acarbose. The greater surface area of nanoparticles exposes the various groups of curcumin for blocking the binding sites of enzymes. This strategy may be helpful in designing curcumin as a potent therapeutic agent against diabetes mellitus. Further, the molecular interactions of curcumin with α-amylase, α-glucosidase, ß-glucosidase, and polyphenol oxidase were assessed by analyzing the plausible binding modes of curcumin in the binding pocket of each receptor. The best binding mode of curcumin was used to make complexes with the target proteins and their stability was confirmed by 50 ns MD simulation.
RESUMEN
To explore the new mode of action and reduce side effects, making conjugates of existing drugs is becoming an attractive tool in the realm of medicinal chemistry. In this work, we exploited this approach and synthesized new conjugates to assess their activities against the enzymes involved in different pathological conditions. Specifically, we design and synthesized conjugates involving acetylsalicylic acid and sulfa drugs, validating the newly crafted conjugates using techniques like IR, 1HNMR, 13CNMR, and elemental analysis. These conjugates underwent assessment for their ability to inhibit cyclooxygenase-2 (COX-2), urease enzymes, and their anti-inflammatory potential. A competitive mode of urease inhibition was observed for acetylsalicylic acid conjugated with sulfanilamide, sulfacetamide, and sulfadiazine with IC50 of 2.49 ± 0.35 µM, 6.21 ± 0.28 µM, and 6.57 ± 0.44 µM, respectively. Remarkably, the acetylsalicylic acid-sulfamethoxazole conjugate exhibited exceptional anti-inflammatory activity, effectively curtailing induced edema by 83.7%, a result akin to the reference anti-inflammatory drug indomethacin's performance (86.8%). Additionally, it demonstrated comparable COX-2 inhibition (75.8%) to the reference selective COX-2 inhibitor celecoxib that exhibited 77.1% inhibition at 10 µM concentration. To deepen our understanding, we employed molecular docking techniques to predict the binding interactions of competitive inhibitors with COX-2 and urease receptors. Additionally, MD simulations were carried out, confirming the stability of inhibitor-target complexes throughout the simulation period, devoid of significant conformational changes. Collectively, our research underscores the potential of coupling approved medicinal compounds to usher in novel categories of pharmacological agents, holding promise for addressing a wide spectrum of pathological disorders involving COX-2 and urease enzymes.Communicated by Ramaswamy H. Sarma.
RESUMEN
Aurora kinases (AURKs) have been identified as promising biological targets for the treatment of cancer. In this study, molecular dynamics simulations were employed to investigate the binding selectivity of three inhibitors (HPM, MPY, and VX6) towards AURKA and AURKB by predicting their binding free energies. The results show that the inhibitors HPM, MPY, and VX6 have more favorable interactions with AURKB as compared to AURKA. The binding energy decomposition analysis revealed that four common residue pairs (L139, L83), (V147, V91), (L210, L154), and (L263, L207) showed significant binding energies with HPM, MPY, and VX6, hence responsible for the binding selectivity of AURKA and AURKB to the inhibitors. The MD trajectory analysis also revealed that the inhibitors affect the dynamic flexibility of protein structure, which is also responsible for the partial selectivity of HPM, MPY, and VX6 towards AURKA and AURKB. As expected, this study provides useful insights for the design of potential inhibitors with high selectivity for AURKA and AURKB.
Asunto(s)
Aurora Quinasa A , Simulación de Dinámica Molecular , Aurora Quinasa A/metabolismo , Aurora Quinasa B/metabolismo , Inhibidores de Proteínas Quinasas/farmacologíaRESUMEN
Tyrosine threonine kinase (TTK) is the key component of the spindle assembly checkpoint (SAC) that ensures correct attachment of chromosomes to the mitotic spindle and thereby their precise segregation into daughter cells by phosphorylating specific substrate proteins. The overexpression of TTK has been associated with various human malignancies, including breast, colorectal and thyroid carcinomas. TTK has been validated as a target for drug development, and several TTK inhibitors have been discovered. In this study, ligand and structure-based alignment as well as various partial charge models were used to perform 3D-QSAR modelling on 1H-Pyrrolo[3,2-c] pyridine core containing reported inhibitors of TTK protein using the comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) approaches to design better active compounds. Different statistical methods i.e., correlation coefficient of non-cross validation (r2), correlation coefficient of leave-one-out cross-validation (q2), Fisher's test (F) and bootstrapping were used to validate the developed models. Out of several charge models and alignment-based approaches, Merck Molecular Force Field (MMFF94) charges using structure-based alignment yielded highly predictive CoMFA (q2 = 0.583, Predr2 = 0.751) and CoMSIA (q2 = 0.690, Predr2 = 0.767) models. The models exhibited that electrostatic, steric, HBA, HBD, and hydrophobic fields play a key role in structure activity relationship of these compounds. Using the contour maps information of the best predictive model, new compounds were designed and docked at the TTK active site to predict their plausible binding modes. The structural stability of the TTK complexes with new compounds was confirmed using MD simulations. The simulation studies revealed that all compounds formed stable complexes. Similarly, MM/PBSA method based free energy calculations showed that these compounds bind with reasonably good affinity to the TTK protein. Overall molecular modelling results suggest that newly designed compounds can act as lead compounds for the optimization of TTK inhibitors.
RESUMEN
Urease has become an important therapeutic target because it stimulates the pathogenesis of many human health conditions, such as pyelonephritis, the development of urolithiasis, hepatic encephalopathy, peptic ulcers, gastritis and gastric cancer. A series of alkyl chain-linked thiourea derivatives were synthesized to screen for urease inhibition activity. Structure elucidation of these compounds was done by spectral studies, such as IR, 1H NMR and 13C NMR, and MS analysis. In vitro urease enzyme inhibition assay revealed that compound 3c was the most potent thiourea derivative among the series with IC50 values of 10.65 ± 0.45 µM, while compound 3g also exhibited good activity with an IC50 value of 15.19 ± 0.58 µM compared to standard thiourea with an IC50 value of 15.51 ± 0.11 µM. The other compounds in the series possessed moderate to weak urease inhibition activity with IC50 values ranging from 20.16 ± 0.48 to 60.11 ± 0.78 µM. The most potent compounds 3c and 3g were docked to jack bean urease (PDB ID: 4H9M) to evaluate their binding affinities and to find the plausible binding poses. The docked complexes were refined through 100 ns-long MD simulations. The simulation results revealed that the average RMSD of 3c was less than that of the 3g compound. Furthermore, the radius of gyration plots for both complexes showed that 3c and 3g docking predicted binding modes did not induce any conformational change in the urease structure.
RESUMEN
For environment-friendly, safe and nonpersistent chemical control of a significant polyphagous insect pest, Helicoverpa armigera, discovery of growth-regulating xenobiotics can offer a sustainable alternative to conventional insecticides. For this purpose, chemically synthesized compounds to inhibit sterol carrier protein (SCP-2) function using in silico and in vivo assays were evaluated to estimate their impact on the survivals and lifetable indices of H. armigera. From nine chemically synthesized compounds, OA-02, OA-06 and OA-09 were selected for this study based on binding poses mimicking cholesterol, a natural substrate of sterol carrier protein and molecular dynamics simulations. In vivo bioassays revealed that all compounds significantly reduced the larval and pupal weight accumulations and stadia lengths. Subsequently, the pupal periods were prolonged upon treatment with higher doses of the selected compounds. Moreover, OA-09 significantly reduced pupation and adult emergence rates as well as the fertility of female moths; however, fecundity remained unaffected, in general. The life table parameters of H. armigera were significantly reduced when treated with OA-09 at higher doses. The population treated with 450 µM of OA-09 had the least net reproductive rates (Ro) and gross reproductive rate (GRR) compared to the control population. The same compound resulted in a declining survival during the early stages of development coupled with reduced larval and pupal durations, and fertility. These results have a significant implication for developing an effective and sustainable chemical treatment against H. armigera infestation.