Drug Target Enzyme Research Articles

One-Pot Green Synthesis and Biological Evaluation of Dimedone-Coupled 2,3-Dihydrofuran Derivatives to Divulge Their Inhibition Potential against Staphylococcal Thioredoxin Reductase Enzyme.

New therapeutic leads are in global demand against multiple drug-resistant Staphylococcus aureus, as presently there is no drug of choice left to treat this pathogen. In the present work, we have designed, synthesized, and in vitro validated dimedone-coupled 2,3-dihydrofuran (DDHF)-based inhibitor scaffolds against Staphylococcal thioredoxin reductase (SaTR), a pivotal drug target enzyme of Gram-positive pathogens. Accordingly, a green multicomponent method that is both efficient and one pot has been optimized to synthesize DDHF derivatives. The synthesized DDHF derivatives were found to inhibit a purified SaTR enzyme. The best inhibitor derivative, DDHF20, inhibits SaTR as a competitive inhibitor for the NADPH binding site at low micromolar concentrations. DDHF20-capped silver nanoparticles are synthesized and characterized, and their bactericidal property has been checked in vitro. Furthermore, detailed in silico-based structure-guided functional studies have been carried out to uncover the plausible mode of action of DDHF20 as a potential anti-Staphylococcal therapeutic lead.

High-Efficiency Enzyme Assay and Screening of Enzyme-Inhibiting Nanomaterials Using Capillary Electrophoresis with Hierarchically Porous Metal-Organic Framework-Based Immobilized Enzyme Microreactor.

Enzyme-inhibiting nanomaterials have significant potential for regulating enzyme activity. However, a universal and efficient method for systematically screening and evaluating the inhibitory effects of various nanomaterials on drug target enzymes has not been established. While the integrated technique of immobilized enzyme microreactor (IMER) with capillary electrophoresis (CE) serves as an effective tool for enzyme analysis, it still faces challenges such as low enzyme loadability, unsatisfactory stability, and limited applicability. Herein, hierarchical porous metal-organic frameworks (HP-MOFs) were explored as high-performance enzyme immobilization carriers and stationary phases to develop a novel HP-MOFs-based IMER-CE microanalysis system for efficient online enzyme assay and systematic screening of enzyme-inhibiting nanomaterials. As a proof-of-concept demonstration, the model enzyme xanthine oxidase (XOD) was immobilized on a HP-UiO-66-NH2 coated capillary, serving as an efficient and durable IMER for screening potential XOD-inhibiting nanomaterials. The hierarchically micro- and mesoporous structure and superior enzyme loadability of as-prepared HP-UiO-66-NH2-IMER was intensively characterized, followed by systematic evaluation of the separation performance of HP-UiO-66-NH2 coated column and the enzyme kinetics of the immobilized XOD. Compared to the microporous UiO-66-NH2-IMER, the HP-UiO-66-NH2-IMER-CE system showed significant improvements in enzyme loading, maximum reaction rate, repeatability, and long-term stability. Furthermore, the established method was effectively employed to screen the XOD inhibitory activity of various nanomaterials, revealing that graphene oxide, single wall carbon nanotube and three other nanomaterials exhibited inhibitory potentials. The HP-MOFs-based microanalysis system can be easily expanded by modifying the types of immobilized enzymes and holds the potential to accelerate the identification and rational design of effective enzyme-inhibiting nanomaterials.

N-Butylphthalide Potentiates the Effect of Fluconazole Against Drug-Resistant Candida glabrata and Candida tropicalis. Evidence for Its Mechanism of Action.

To define the antifungal activity of n-butylphthalide alone or in combination with fluconazole in Candida glabrata and Candida tropicalis. The antifungal activity of n-butylphthalide alone and in combination with fluconazole was investigated by the classical broth microdilution method and the time-killing curve method. The QRT-PCR method was used to determine gene expressions changes of mitochondrial respiratory chain enzymes, drug efflux pumps and drug target enzymes in Candida glabrata and Candida tropicalis after n-butylphthalide treatment. The MIC values of n-butylphthalide against Candida glabrata and Candida tropicalis ranged from 16 to 64 μg·mL-1. The FICI value of the combination of n-butylphthalide and fluconazole against drug-resistant Candida glabrata and Candida tropicalis ranged from 0.5001 to 0.5315 with partial synergism. Time-killing curves showed that 256 μg·mL-1 n-butylphthalide significantly inhibited the growth of drug-resistant colonies of Candida glabrata and Candida tropicalis, and 128 μg·mL-1 n-butylphthalide combined with 1 μg·mL-1 fluconazole had an additive effect. N-butylphthalide could alter the expression of mitochondrial respiratory chain enzymes COX1, COX2, COX3, and CYTB genes in Candida glabrata and Candida tropicalis (P< 0.05) and downregulate the expression of the drug efflux pump genes CDR1 and CDR2 in drug-resistant Candida glabrata to 3.36% and 3.65%, respectively (P<0.001), but did not affect the drug target enzyme ERG11 in drug-resistant Candida tropicalis. N-butylphthalide had antifungal activity against Candida glabrata and Candida tropicalis. N-butylphthalide improved the activity of fluconazole against drug-resistant Candida glabrata by affecting the expression of mitochondrial respiratory chain enzyme genes and reversing the high expression of drug efflux pump genes CDR1 and CDR2.

Synthesis, characterization, anti‐proliferative evaluation, and molecular docking study of some new N‐(1, 3‐dioxoisoindolin‐4‐yl)acetamide derivatives

AbstractA series of new N‐(1,3‐dioxoisoindolin‐4‐yl)acetamide derivatives were designed and synthesized via a condensation reaction between N‐(1,3‐dioxo‐1,3‐dihydro isobenzofuran‐4‐yl)acetamide and various aliphatic and aromatic amines in water as an environmentally friendly solvent. All synthesized compounds (NPD 1–14) molecular structure was confirmed by their FTIR, 1H NMR, 13C NMR, and mass spectroscopy. The final target compounds were screened for their in vitro antiproliferative activity by taking 5‐Fluorouracil (5‐FU) as a reference drug. Among 14 newly synthesized compounds, five compounds were shown to be effectively cytotoxic against the MCF7 cells. In comparison to the standard medication drug 5‐FU (CC50 = 11.219 ± 0.847), the synthesized compounds NPD‐8 (CC50 = 16.14 ± 2.08 μM) and NPD‐12 (CC50 = 11.26 ± 1.158 μM) demonstrated the most active against the MCF7 cells. Furthermore, in silico study was performed to find molecular level interaction of active compounds with anticancer drug target enzyme NUDT5 inhibitors block hormone signaling in breast cancer cells. The compound NPD‐12 showed the highest molecular binding energy −8.3 kcal/mol which interacted more effectively than the reference drug 5‐FU binding energy −4.6 kcal/mol. These synthesized N‐(1,3‐dioxoisoindolin‐4‐yl) acetamide derivatives have been identified as a potential class of chemicals for further research as plausible new anticancer entities.

Abstract 3767: Identification of regulators of epigenetic silencing of the p16INK4a gene

Abstract Epigenetic silencing of tumor suppressor genes plays critical roles in oncogenesis. The CDKN2A/p16INK4a gene is one of the most frequently silenced tumor suppressor genes. To elucidate molecular mechanisms of maintenance of the silenced status of the p16INK4a gene, we applied the insertional chromatin immunoprecipitation (iChIP) method. The promoter region of the transcriptionally active and silenced alleles of the p16INK4a gene were tagged with a bacterial DNA-binding protein LexA and its binding elements. Subsequently, the promoter regions were affinity purified with antibody against a tag fused with LexA. Proteins more or less abundantly associated with the silenced promoter were identified by stable isotope labeling using amino acids in cell culture (SILAC), one of quantitative mass spectrometry methods. Knock-down experiments of the identified enzymes revealed essential components of maintenance of epigenetic silencing. The essential enzymes can be good targets of development of drugs reactivating expression of the silenced tumor suppressor genes in cancers. We are currently performing drug discovery research to identify small molecules that bind and inhibit those candidate drug target enzymes. Our locus-specific ChIP technology consisting of iChIP and the engineered DNA-binding molecule-mediated ChIP (enChIP) method is a powerful tool to identify novel drug targets for development of drugs regulating gene expression in intractable diseases. Citation Format: Toshitsugu Fujita, Hodaka Fujii. Identification of regulators of epigenetic silencing of the p16INK4a gene [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3767.

Streptomyces sp. Vitnk9 derived compound against fish bacterial pathogens

Background: The extensive research in the field of aquaculture is essential to combat the fish bacterial diseases causing massive economic loss to the aquaculture industry and these pathogens remains to be a threat to human well-being due to consumption of fish and fish products as a major food source. Methods: This study focuses on extraction and identification of the antibacterial compound produced by Streptomyces sp. VITNK9 against selected fish bacterial pathogens. Results: Bioactivity-guided extraction of ethyl acetate extract and purification results in isolation of the lead compound 1-(2-hydroperoxycyclopentyl)-4-hydroxytridecan-7-one (HCHD) from Streptomyces sp. VITNK9 having a chemical formula of C18H34O4 and a molecular weight of 314.46 g/mol. HCHD (100 μg/ml) demonstrated antibacterial activity with the inhibition zone of 19.33 ± 0.47 mm and the MIC (minimal inhibitory concentration) of 3.125 μg/ml toward Edwardsiella tarda and 16.66 ± 0.47 mm and the MIC value of 12.5 μg/ml against Aeromonas hydrophila. In silico molecular docking studies showed the interaction of HCHD with the drug target enzyme acetate kinase of E. tarda and A. hydrophila. It showed the least binding free energy of-6.5Kcal/mol and-6.1 Kcal/mol with acetate kinase of E. tarda and A. hydrophila, respectively. Conclusion: The outcome of this study suggests that the inhibition of bacterial acetate kinase by the lead compound HCHD and thereby affects the bacterial metabolism. Streptomyces species are more promising source for isolating antibacterial secondary metabolites for controlling fish bacterial pathogens.

Vanillin containing 9H-fluoren sulfone scaffolds: Synthesis, biological evaluation and molecular docking study

Vanillin containing 9H-fluoren sulfone scaffolds were prepared by coupling a sulfone amine with carboxylic acid group of amino acids in presence of peptide coupling reagent hexafluorophosphate benzotriazole tetramethyl uronium (HBTU). All eight (6a–6h) synthesized vanillin containing 9H-fluoren sulfone scaffolds were evaluated for their biological activities, namely, antibacterial, antifungal and antimalarial. The antibacterial evaluation revealed that compounds 6b-6g exhibited potency against tested pathogenic bacteria, especially against Staphylococcus aureus. Compounds 6b, 6f and 6h manifested considerable antifungal activities against Candida albicans, Aspergillus niger and A. clavatus. Moreover, the antimalarial result demonstrated excellent antimalarial activities for compounds 6b and 6f against Plasmodium falciparum with IC50 less than the standard quinine. Further, molecular docking study was performed to find molecular level interaction of compounds with malarial drug target enzyme P. falciparum dihydrofolate reductase-thymidylate synthase (pfdher-ts). Interestingly, for all tested sulfone scaffolds the docking energy was found between −8.6 to −10.6 kcal/mol, which was higher than both of the standard drugs’ (quinine and chloroquine) docking energy, i.e. −8.4 and −6.9, respectively. The results of this study confirmed the importance of the sulfone class of compounds in the treatment of parasitic infections and microbial infections.

Design, Synthesis, and Biological Evaluation of Densely Substituted Dihydropyrano[2,3-c]pyrazoles via a Taurine-Catalyzed Green Multicomponent Approach.

An efficient taurine-catalyzed green multicomponent approach has been described for the first time to synthesize densely substituted therapeutic core dihydropyrano[2,3-c]pyrazoles. Applications of the developed synthetic strategies and technologies revealed the synthesis of a series of newly designed 1,4-dihydropyrano[2,3-c]pyrazoles containing isonicotinamide, spirooxindole, and indole moieties. Detailed in silico analysis of the synthesized analogues revealed their potential to bind wild-type and antibiotic-resistant variants of dihydrofolate reductase, a principal drug target enzyme for emerging antibiotic-resistant pathogenic Staphylococcus aureus strains. Hence, the synthesized dihydropyrano[2,3-c]pyrazole derivatives presented herein hold immense promise to develop future antistaphylococcal therapeutic agents.

Deep Learning Methods in Predicting Gene Expression Levels for the Malaria Parasite.

Malaria is a mosquito-borne disease caused by single-celled blood parasites of the genus Plasmodium. The most severe cases of this disease are caused by the Plasmodium species, Falciparum. Once infected, a human host experiences symptoms of recurrent and intermittent fevers occurring over a time-frame of 48 hours, attributed to the synchronized developmental cycle of the parasite during the blood stage. To understand the regulated periodicity of Plasmodium falciparum transcription, this paper forecast and predict the P. falciparum gene transcription during its blood stage life cycle implementing a well-tuned recurrent neural network with gated recurrent units. Additionally, we also employ a spiking neural network to predict the expression levels of the P. falciparum gene. We provide results of this prediction on multiple genes including potential genes that express possible drug target enzymes. Our results show a high level of accuracy in being able to predict and forecast the expression levels of the different genes.

Genome-Wide Approach to Measure Variant-Based Heritability of Drug Outcome Phenotypes.

Pharmacogenomic studies have successfully identified variants-typically with large effect sizes in drug target and metabolism enzymes-that predict drug outcome phenotypes. However, these variants may account for a limited proportion of phenotype variability attributable to the genome. Using genome-wide common variation, we measured the narrow-sense heritability ( ) of seven pharmacodynamic and five pharmacokinetic phenotypes across three cardiovascular drugs, two antibiotics, and three immunosuppressants. We used a Bayesian hierarchical mixed model, BayesR, to model the distribution of genome-wide variant effect sizes for each drug phenotype as a mixture of four normal distributions of fixed variance (0, 0.01%, 0.1%, and 1% of the total additive genetic variance). This model allowed us to parse into bins representing contributions of no-effect, small-effect, moderate-effect, and large-effect variants, respectively. For the 12 phenotypes, a median of 969 (range 235-6,304) unique individuals of European ancestry and a median of 1,201,626 (range 777,427-1,514,275) variants were included in our analyses. The number of variants contributing to ranged from 2,791 to 5,356 (median 3,347). Estimates for ranged from 0.05 (angiotensin-converting enzyme inhibitor-induced cough) to 0.59 (gentamicin concentration). Small-effect and moderate-effect variants contributed a majority to for every phenotype (range 61-95%). We conclude that drug outcome phenotypes are highly polygenic. Thus, larger genome-wide association studies of drug phenotypes are needed both to discover novel variants and to determine how genome-wide approaches may improve clinical prediction of drug outcomes.

English

Zerumbone (ZER) is a well-known sesquiterpene composite can be set up in the rhizomes of Zingiber zerumbet (Smith), having anti-cancer, anti-inflammatory and anti-hyperglycemic effects. This study aimed to investigate the inhibitory potential of ZER against drug-target enzymes involved in human pathologies, namely, obesity (Pancreatic lipase) and idiopathic intracranial hypertension (carbonic anhydrase). Result: ZER inhibits pancreatic lipase and carbonic anhydrase at percentages of 52.5 and 71.3% with 184.1±5 and 69.3±0.43 μg/mL IC50 values, respectively. Consequently, ZER has an excellent inhibitory action against pancreatic lipase and carbonic anhydrase, making it interesting anti-obesity drug candidate and avert pathophysiological-related carbonic anhydrase

Pharmacokinetic and Pharmacodynamic Considerations in Relation to Calcineurin Usage in Elderly Kidney Transplant Recipients.

This review summarizes how possible age-related changes in tacrolimus and cyclosporine pharmacokinetics and pharmacodynamics may influence drug dosing and monitoring in the elderly, and highlights how micro-sampling may be useful in this cohort in the future. Advancing biological age leads to physiological changes that can affect drug absorption, distribution, metabolism and excretion, as well as immune system responsiveness. Some studies have shown that elderly recipients may have higher dose-adjusted exposure and/or lower clearance of the calcineurin inhibitors, suggesting that doses may need to be lowered in elderly recipients. Only one study has examined how aging effects drug target enzyme activity and demonstrated that age does not correlate with the calcineurin inhibitor half-maximal inhibitory concentration. Several studies have shown elderly kidney transplant recipients have increased risk of both morbidity and mortality, compared to younger adults due to increased susceptibility to immunosuppressant side effects, particularly cardiovascular disease, infection and malignancy. Current immunosuppressant dosing and monitoring protocols often make no adjustments for age. Lower maintenance immunosuppressant targets in elderly recipients may decrease patient susceptibility to drug side effects, however, further studies are required and appropriate targets need to be established. Blood draw by micro-sampling may be useful for drug monitoring in this cohort in the future, as blood collection is minimally invasive and less painful than venepuncture. Micro-sampling could also make further pharmacokinetic, pharmacodynamics and outcome studies in the elderly more feasible.

Carfilzomib as a potential inhibitor of NADH-dependent enoyl-acyl carrier protein reductases of Klebsiella pneumoniae and Mycobacterium tuberculosis as a drug target enzyme: insights from molecular docking and molecular dynamics

Multiple antibiotic-resistant strains of Klebsiella pneumoniae can cause life-threatening infections. Bacterial enoyl-acyl carrier protein (ACP) reductases (ENRs) are considered critical targets for developing antibiotics. Our current study aims to identify inhibitors of K. pneumoniae ENRs (FabI and FabV). Due to the unavailability of experimental structures, protein models of FabI and FabV were predicted and validated in this study. Virtual screening of the 1930 FDA-approved drug database was conducted against the active site of the FabI protein with the help of the LEA3D server, and carfilzomib was chosen among the screened drugs for further docking studies. Carfilzomib, a proteasome inhibitor used in the treatment of multiple myeloma, was among the best-suited compounds obtained from the virtual screening and was found to be bactericidal in the in vitro experiment. Carfilzomib was docked against the active sites of the FabI and FabV proteins, and the ENR of Mycobacterium tuberculosis, InhA. Carfilzomib showed a high binding affinity with all three proteins. Molecular dynamics (MD) simulations were conducted following the docking studies. MD simulations revealed that carfilzomib binds strongly to the active sites of the above mentioned ENRs. Our study found that carfilzomib is a potential inhibitor of the ENRs of K. pneumoniae and M. tuberculosis. This is a possible mechanism of its bactericidal property against M. tuberculosis observed in vitro in addition to its predicted actions on zinc-dependent metalloprotease-1 and peptide deformylase, two other drug target enzymes of M. tuberculosis. Our study suggests that this drug could be used as a lead compound to develop antibiotics that can selectively act against ENRs of bacteria, without interfering with the activities of human proteasome. Communicated by Ramaswamy H. Sarma

Characterizing the pharmacokinetics and pharmacodynamics of immunosuppressant medicines and patient outcomes in elderly renal transplant patients.

This review examines what is currently known about the pharmacokinetics and pharmacodynamics of commonly prescribed immunosuppressant medicines, tacrolimus, cyclosporine, mycophenolate and prednisolone, in elderly renal transplant recipients, and reported patient outcomes in this cohort. Renal transplantation is increasing rapidly in the elderly, however, currently, long-term patient outcomes are relatively poor compared to younger adults. Some studies have suggested that elderly recipients may have higher dose-adjusted exposure and/or lower clearance of the calcineurin inhibitors tacrolimus and cyclosporine; with one study reporting up to 50% reduction in tacrolimus exposure in the elderly. Elderly transplant recipients do not appear to have higher dosage-adjusted exposure to mycophenolic acid (MPA). The effects of ageing on the pharmacokinetics of prednisolone are unknown. Only one study has examined how aging effects drug target enzymes, reporting no difference in baseline inosine 5'-monophosphate dehydrogenase (IMPDH) activity and MPA-induced IMPDH activity in elderly compared to younger adult renal transplant recipients. In elderly transplant recipients, immunosenescence likely lowers the risk of acute rejection, but increases the risk of drug-related adverse effects. Currently, the three main causes of death in elderly renal transplant recipients are cardiovascular disease, infection and malignancy. One study has showed that renal transplant recipients aged over 65 years are seven times more likely to die with a functioning graft compared with young adults (aged 18-29 years). This suggests that an optimal balance between immunosuppressant medicine efficacy and toxicity is not achieved in elderly recipients, and further studies are needed to foster long-term graft and patient survival. Lower maintenance immunosuppressant targets in elderly recipients may decrease patient susceptibility to drug side effects, however, further studies are required and appropriate targets need to be established.

FOXP3 and Its Cofactors as Targets of Immunotherapies

Abstract Forkhead box P3 (FOXP3) is a “master regulator” of regulatory T cells (Tregs), which are a subset of T cells that can suppress the antigen-specific immune reaction and that play important roles in host tolerance and immune homeostasis. It is well known that FOXP3 forms complexes with several proteins and can be regulated by various post-translational modifications (PTMs) such as acetylation, phosphorylation, ubiquitination, and methylation. As a consequence, the PTMs change the stability of FOXP3 and its capability to regulate gene expression, and eventually affect Treg activity. Although FOXP3 per se is not an ideal drug target, deacetylases, acetyltransferases, kinases, and other enzymes that regulate the PTMs of FOXP3 are potential targets to modulate FOXP3 and Treg activity. However, FOXP3 is not the only substrate for most of these enzymes; thus, unwanted “on target/off FOXP3” side effects must be considered when inhibitors to these enzymes are used. In this review, we summarize recent progress in the study of FOXP3 cofactors and PTM proteins, and potential clinical applications in autoimmunity and cancer immunity.

Molecular Docking Analysis of Caspase-3 Activators as Potential Anticancer Agents.

Caspase-3 plays a leading role in apoptosis and on activation, it cleaves many protein substrates in cells and causes cell death. Since many chemotherapeutics are known to induce apoptosis in cancer cells, promotion or activation of apoptosis via targeting apoptosis regulators has been suggested as a promising strategy for anticancer drug discovery. In this paper, we studied the interaction of 1,2,4-Oxadiazoles derivatives with anticancer drug target enzymes (PDB ID 3SRC). Molecular docking studies were performed on a series of 1,2,4-Oxadiazoles derivatives to find out molecular arrangement and spatial requirements for their binding potential for caspase-3 enzyme agonistic affinity to treat cancer. The Autodock 4.2 and GOLD 5.2 molecular modeling suites were used for the molecular docking analysis to provide information regarding important drug receptor interaction. Both suites explained the spatial disposition of the drug with the active amino acid in the ligand binding domain of the enzyme. The amino acid asparagine 273 (ASN 273) of target has shown hydrogen bond interaction with the top ranked ligand.

Ichnocarpus frutescens (L.) R. Br. root derived phyto-steroids defends inflammation and algesia by pulling down the pro-inflammatory and nociceptive pain mediators: An in-vitro and in-vivo appraisal

Ichnocarpus frutescens, a climber plant, is distributed all over India. As its different parts are used as anti-inflammatory agent, so we re-investigated the roots to isolate compounds and evaluate its biological efficacy. Also, in-silico molecular docking was carried out to elucidate the structure activity relationship (SAR) of isolated compounds toward identifies the drug target enzyme with validation, which was further supported by anti-inflammatory in-vitro and in-vivo experimental models. The compounds have been undertaken mainly to investigate the anti-inflammatory and analgesic efficacy along with molecular docking investigation followed by anti-proteinase, anti-denaturation and cyclooxygenase (COX) inhibition studies. Inflammatory cytokines like TNF-α and IL-6 were assayed from lipopolysaccharides (LPS) and Concavallin (CON A) stimulated human PBMC derived macrophages by Enyme linked immune sorbent assay (ELISA) method. The purity index of the lead compound was determined by HPLC. The compounds were illustrated as 2-hydroxy tricosanoic acid (1), stigmasterol glucoside (2), stigmasterol (3), β-sitosterol (4) and β-sitosterol glucoside (5). The test molecules showed significant anti-denaturation, anti-proteinase and analgesic effect validated with docking study. Compounds exhibited anti-inflammatory and pain killing action due to dexamethasone like phytosterol property. Promising anti-denaturation and anti-proteinase activity offered by the compound 5, may hold its promise to fight against arthritis by rejuvenating the osteoblast cells and destroying the bone-resorpting complex of hydrated protein, bone minerals by secreting the acid and an enzyme collagenase along with pain management. The lead bioactive compound i.e. β-sitosterol glucoside (compound 5) demonstrated considerable anti-inflammatory activity showing more than 90% protection against the inflammatory cytokines at 50 µM dose. The anti-denaturation and COX-2 inhibition shown by the compound 5 was also noteworthy with the significant IC50 (ranging from 0.25 to 2.56 µM) that also supporting its future promise for developing as anti-inflammatory agent. Since the most bio-active compound (5) elicit promising acute anti-inflammatory action and peripheral anti-nociceptive pain killing action with a significant ED50 dose of 3.95 & 2.84 mg/kg i.p. respectively in the in-vivo animal model. It could suggest its potentiality as a good in-vivo bio available agent to be an emerging anti-inflammatory drug regimen scaffold in the future. It also establishes significant in-vitro and in-vivo result co-relation.Therefore, the compound 5 could be believed as a potent lead for designing anti-inflammatory, anti-arthritic drug or pain killer without showing any untoward effect.

Antibacterial and antifungal potential of marine Streptomyces sp. VITAK1 derived novel compound Pyrrolidinyl-Hexadeca-Heptaenone by in Silico docking analysis

The rapid emergence of antibiotic resistance by pathogenic bacteria underlines the need for new antibacterial agents from natural sources. With those objective marine actinomycetes derived novel compound was screened for antibacterial and antifungal activity by in-silico molecular docking studies. Twelve actinomycetes were isolated from marine soil samples collected from Andaman and Nicobar Islands of India. All the isolates were screened for antibacterial activity against selected ATCC bacterial pathogens and the isolate VITAK1 showed significant antibacterial activity. It was characterized by molecular taxonomic and phylogeny and identified as Streptomyces species and designated as Streptomyces sp. VITAK1. The 16S rRNA partial gene sequence (1296 nucleotides) of VITAK1 was submitted to the GenBank under the accession ID: KF478916. Bioactivity-guided extraction, purification and characterization of the compound through GC-MS, FT-IR and NMR (H1and C13) lead to the identification of compound, [(3E, 5E, 7E, 9E, 11E, 13E, 15E)-16-(pyrrolidin-1-yl) hexadeca-3, 5, 7, 9, 11, 13, 15-heptaen-2-one] with a molecular weight of 295.41 Da and molecular formula C20H25NO. The extracted compound was found to be anovelbased on PUBCHEM and SciFinderdatabase. The compound exhibited the least free binding energy of -8.8 Kcal/mol with the fungal drug target enzyme N-myristoyl transferase and also showed the free binding energy of -8.14 Kcal/mol with folate synthesising enzyme dihydropteroate synthase. The results of the in Silico studies suggest that the novel compound PHDH exhibit antibacterialactivity by inhibiting folate synthesis in the target bacteria and antifungal activity by inhibiting the ergosterol synthesis.

Understanding the Catalytic Mechanism and the Nature of the Transition State of an Attractive Drug-Target Enzyme (Shikimate Kinase) by Quantum Mechanical/Molecular Mechanical (QM/MM) Studies.

Shikimate kinase (SK) is the fifth bacterial enzyme involved in the shikimate pathway for biosynthesis of life-indispensable components, such as aromatic amino acids. The absence of the shikimate pathway in humans makes SK an attractive target for the rational design of drugs aimed at pathogenesis bacteria, such as Mycobacterium tuberculosis and Helicobacter pylori. However, an effective inhibitor of SK (e.g., a transition-state analogue) is still not available on the market due, at least in part, to a lack of knowledge on the catalytic mechanism and the nature of the rate-limiting transition state. Herein, quantum mechanical/molecular mechanical (QM/MM) reaction coordinate, molecular dynamics (MD), and free-energy simulations have been performed to answer these questions. The results presented herein demonstrate that the phosphoryl-transfer process, which is the rate-limiting step of SK-catalyzed phosphorylation of shikimic acid (SKM), is a concerted one-step reaction proceeding through a loose transition state. The computational results agree well with those of experimental studies, specifically NMR results, X-ray crystal structure observation, and activation free-energy barrier.

Quinazoline-1-deoxynojirimycin hybrids as high active dual inhibitors of EGFR and α-glucosidase

A series of novel quinazoline-1-deoxynojirimycin hybrids were designed, synthesized and evaluated for their inhibitory activities against two drug target enzymes, epidermal growth factor receptor (EGFR) tyrosine kinase and α-glucosidase. Some synthesized compounds exhibited significantly inhibitory activities against the tested enzymes. Comparing with reference compounds gefitinib and lapatinib, compounds 7d, 8d, 9b and 9d showed higher inhibitory activities against EGFR (IC50: 1.79–10.71nM). Meanwhile the inhibitory activities of 7d, 8d and 9c against α-glucosidase (IC50=0.14, 0.09 and 0.25µM, respectively) were obvious higher than that of miglitol (IC50=2.43µM), a clinical using α-glucosidase inhibitor. Interestingly, compound 9d as a dual inhibitor showed high inhibitory activity to EGFRwt tyrosine kinase (IC50=1.79nM), also to α-glucosidase (IC50=0.39µM). The work could be very useful starting point for developing a new series of enzyme inhibitors targeting EGFR and/or α-glucosidase.