To quest new targets of Plasmodium parasite and their potential inhibitors to combat antimalarial drug resistance.

Malaria remains a global health challenge with significant mortality and morbidity annually, with resistant parasite strains complicating treatment efforts. There is an acute need for novel antimalarial drugs that can put a stop to the future public health crisis caused by the multi-drug resistance strains of the Plasmodium parasite. However, the discovery of these new components is very challenging in the context of the generation of multi-drug resistance properties of malaria. The novel drugs also need to have several properties involving enhanced therapeutic prospects, successful treatment capabilities, and novel mechanisms of action that will forestall the resistance. To successfully achieve this aim researchers are trying to focus on exploring promising malaria targets. Various approaches have been made for the development of drugs for malaria including the remodelling of existing drugs and the development of novel inhibitors which acts on new targets. Advancement in the study provides more information on the biology of parasites and the new targets which help in the development of novel drugs. The present review focuses on the study of novel targets of malaria parasites and subsequent inhibitors of those particular targets. Some of these targets include malarial protease, various transporter proteins, enzymes involved in the synthesis of DNA, and nucleic acids like dihydroorotate dehydrogenase, dihydrofolate reductase, apicoplast and dihydropteroate synthase. Other potential targets are also included in this review such as isoprenoid biosynthesis, farnesyl transferase of parasite, P. falciparum translational elongation factor 2, and phosphatidyl inositol 4 kinase. These promising targets have also been summed up along with their corresponding inhibitors for combating multi-drug resistance malaria.

Anticancer Activity of Imidazolyl Gold(I/III) Compounds in Non-Small Cell Lung Cancer Cell Lines.

Lung cancer is a leading cause of cancer-related death worldwide that needs updated therapies to contrast both the serious side effects and the occurrence of drug resistance. A panel of non-small cell lung cancer (NSCLC) cells were herein employed as cancer models. Eight structurally related gold(I) and gold(III) complexes with NHC and halides or triphenylphosphane ligands were investigated as lung cancer cell growth inhibitors. As expected, gold compounds with PPh3 were found to be more cytotoxic than homoleptic [(NHC)2-Au(I)]X or heteroleptic NHC-Au(I)X or NHC-Au(III)X3 complexes. Mixed ligand gold(I) compounds exhibiting the linear NHC-AuPPh3 (compound 7) or the trigonal NHC-Au(Cl)PPh3 (compound 8) arrangements at the central metal were found to be the best lung cancer cytotoxic compounds. Analysis of the TrxR residual activity of the treated cells revealed that these compounds efficiently inhibit the most accredited molecular target for gold compounds, the TrxR, with compound 8 reaching more than 80% activity reduction in lung cells. Some of the current cancer lung therapy protocols consist of specific lung cancer cell cytotoxic agents combined with antifolate drugs; interestingly, the herein gold compounds are both TrxR and antifolate inhibitors. The human DHFR was inhibited with IC50 ranging between 10-21 µM, depending on substrate concentrations, proceeding by a likely allosteric mechanism only for compound 8.

Tryptophan Metabolism in Obesity: The Indoleamine 2,3-Dioxygenase-1 Activity and Therapeutic Options.

Obesity activates both innate and adaptive immune responses in adipose tissue. Adipose tissue macrophages are functional antigen-presenting cells that promote the proliferation of interferon-gamma (IFN-γ)-producing cluster of differentiation (CD)4+ T cells in adipose tissue of obese subjects. The increased formation of neopterin and degradation of tryptophan may result in decreased T-cell responsiveness and lead to immunodeficiency. The activity of inducible indoleamine 2,3-dioxygenase-1 (IDO1) plays a major role in pro-inflammatory, IFN-γ-dominated settings. The expression of several kynurenine pathway enzyme genes is significantly increased in obesity. IDO1 in obesity shifts tryptophan metabolism from serotonin and melatonin synthesis to the formation of kynurenines and increases the ratio of kynurenine to tryptophan as well as with neopterin production. Reduction in serotonin (5-hydroxytryptamine; 5-HT) production provokes satiety dysregulation that leads to increased caloric uptake and obesity. According to the monoamine-deficiency hypothesis, a deficiency of cerebral serotonin is involved in neuropsychiatric symptomatology of depression, mania, and psychosis. Indeed, bipolar disorder (BD) and related cognitive deficits are accompanied by a higher prevalence of overweight and obesity. Furthermore, the accumulation of amyloid-ß in Alzheimer's disease brains has several toxic effects as well as IDO induction. Hence, abdominal obesity is associated with vascular endothelial dysfunction. kynurenines and their ratios are prognostic parameters in coronary artery disease. Increased kynurenine/tryptophan ratio correlates with increased intima-media thickness and represents advanced atherosclerosis. However, after bariatric surgery, weight reduction does not lead to the normalization of IDO1 activity and atherosclerosis. IDO1 is involved in the mechanisms of immune tolerance and in the concept of tumor immuno-editing process in cancer development. Serum IDO1 activity is still used as a parameter in cancer development and growth. IDO-producing tumors show a high total IDO immunostaining score, and thus, using IDO inhibitors, such as Epacadostat, Navoximod, and L isomer of 1-methyl-tryptophan, seems an important modality for cancer treatment. There is an inverse correlation between serum folate concentration and body mass index, thus folate deficiency leads to hyperhomocysteinemia-induced oxidative stress. Immune checkpoint blockade targeting cytotoxic T-lymphocyte-associated protein-4 synergizes with imatinib, which is an inhibitor of mitochondrial folate-mediated one-carbon (1C) metabolism. Antitumor effects of imatinib are enhanced by increasing T-cell effector function in the presence of IDO inhibition. Combining IDO targeting with chemotherapy, radiotherapy and/or immunotherapy, may be an effective tool against a wide range of malignancies. However, there are some controversial results regarding the efficacy of IDO1 inhibitors in cancer treatment.

High throughput mutational scanning of a protein via alchemistry on a high-performance computing resource.

Antibiotic resistance presents a significant challenge to public health, as bacteria can develop resistance to antibiotics through random mutations during their life cycles, making the drugs ineffective. Understanding how these mutations contribute to drug resistance at the molecular level is crucial for designing new treatment approaches. Recent advancements in molecular biology tools have made it possible to conduct comprehensive analyses of protein mutations. Computational methods for assessing molecular fitness, such as binding energies, are not as precise as experimental techniques like deep mutational scanning. Although full atomistic alchemical free energy calculations offer the necessary precision, they are seldom used to assess high throughput data as they require significantly more computational resources. We generated a computational library using deep mutational scanning for dihydrofolate reductase (DHFR), a protein commonly studied in antibiotic resistance research. Due to resource limitations, we analyzed 33 out of 159 positions, identifying 16 single amino acid replacements. Calculations were conducted for DHFR in its drug-free state and in the presence of two different inhibitors. We demonstrate the feasibility of such calculations, made possible due to the enhancements in computational resources and their optimized use.

Unveiling the Connection: Viral Infections and Genes in dNTP Metabolism.

Deoxynucleoside triphosphates (dNTPs) are crucial for the replication and maintenance of genomic information within cells. The balance of the dNTP pool involves several cellular enzymes, including dihydrofolate reductase (DHFR), ribonucleotide reductase (RNR), and SAM and HD domain-containing protein 1 (SAMHD1), among others. DHFR is vital for the de novo synthesis of purines and deoxythymidine monophosphate, which are necessary for DNA synthesis. SAMHD1, a ubiquitously expressed deoxynucleotide triphosphohydrolase, converts dNTPs into deoxynucleosides and inorganic triphosphates. This process counteracts the de novo dNTP synthesis primarily carried out by RNR and cellular deoxynucleoside kinases, which are most active during the S phase of the cell cycle. The intracellular levels of dNTPs can influence various viral infections. This review provides a concise summary of the interactions between different viruses and the genes involved in dNTP metabolism.

Characterization of the Three DHFRs and K65P Variant: Enhanced Substrate Affinity and Molecular Dynamics Analysis.

Dihydrofolate reductase (DHFR) is ubiquitously present in all living organisms and plays a crucial role in the growth of the fungal pathogen R.solani. Sequence alignment confirmed the evolutionary conservation of the essential lid domain, with the amino acid 'P' within the PEKN lid domain appearing with a frequency of 89.5% in higher organisms and 11.8% in lower organisms. Consequently, a K65P variant was introduced into R.solani DHFR (rDHFR). Subsequent enzymatic kinetics assays were conducted for human DHFR (hDHFR), rDHFR, E. coli DHFR (eDHFR), and the K65P variant. hDHFR exhibited the highest kcat of 0.95 s-1, followed by rDHFR with 0.14 s-1, while eDHFR displayed the lowest kcat of 0.09 s-1. Remarkably, the K65P variant induced a significant reduction in Km, resulting in a 1.8-fold enhancement in catalytic efficiency (kcat/Km) relative to the wild type. Differential scanning fluorimetry and binding free energy calculations confirmed the enhanced substrate affinity for both folate and NADPH in the K65P variant. These results suggest that the K65P mutation enhances substrate affinity and catalytic efficiency in DHFR, highlighting the evolutionary and functional importance of the K65 residue.

Viral communities in a pH>10 serpentinite-like environment: insight into diversity and potential roles in modulating the microbiomes by bioactive vitamin B9 synthesis.

Viral communities exist in a variety of ecosystems and play significant roles in mediating biogeochemical processes, whereas viruses inhabiting strongly alkaline geochemical systems remain underexplored. In this study, the viral diversity, potential functionalities, and virus-host interactions in a strongly alkaline environment (pH = 10.4-12.4) exposed to the leachates derived from the serpentinization-like reactions of smelting slags were investigated. The viral populations (e.g., Herelleviridae, Queuovirinae, and Inoviridae) were closely associated with the dominating prokaryotic hosts (e.g., Meiothermus, Trueperaceae, and Serpentinomonas) in this ultrabasic environment. Auxiliary metabolic genes (AMGs) suggested that viruses may enhance hosts' fitness by facilitating cofactor biosynthesis, hydrogen metabolism, and carbon cycling. To evaluate the activity of synthesis of essential cofactor vitamin B9 by the viruses, a viral folA (vfolA) gene encoding dihydrofolate reductase (DHFR) was introduced into a thymidine-auxotrophic strain Escherichia coli MG1655 ΔfolA mutant, which restored the growth of the latter in the absence of thymidine. Notably, the homologs of the validated vDHFR were globally distributed in the viromes across various ecosystems. The present study sheds new light on the unique viral communities in hyperalkaline ecosystems and their potential beneficial impacts on the coexisting microbial consortia by supplying essential cofactors. IMPORTANCE: This study presents a comprehensive investigation into the diversity, potential functionalities, and virus-microbe interactions in an artificially induced strongly alkaline environment. Functional validation of the detected viral folA genes encoding dihydrofolate reductase substantiated the synthesis of essential cofactors by viruses, which may be ubiquitous, considering the broad distribution of the viral genes associated with folate cycling.

Dysregulation of hepatic one-carbon metabolism in classical homocystinuria: Implications of redox-sensitive DHFR repression and tetrahydrofolate depletion for pathogenesis and treatment.

Cystathionine beta-synthase-deficient homocystinuria (HCU) is a life-threatening disorder of sulfur metabolism. HCU can be treated by using betaine to lower tissue and plasma levels of homocysteine (Hcy). Here, we show that mice with severely elevated Hcy and potentially deficient in the folate species tetrahydrofolate (THF) exhibit a very limited response to betaine indicating that THF plays a critical role in treatment efficacy. Analysis of a mouse model of HCU revealed a 10-fold increase in hepatic levels of 5-methyl -THF and a 30-fold accumulation of formiminoglutamic acid, consistent with a paucity of THF. Neither of these metabolite accumulations were reversed or ameliorated by betaine treatment. Hepatic expression of the THF-generating enzyme dihydrofolate reductase (DHFR) was significantly repressed in HCU mice and expression was not increased by betaine treatment but appears to be sensitive to cellular redox status. Expression of the DHFR reaction partner thymidylate synthase was also repressed and metabolomic analysis detected widespread alteration of hepatic histidine and glutamine metabolism. Many individuals with HCU exhibit endothelial dysfunction. DHFR plays a key role in nitric oxide (NO) generation due to its role in regenerating oxidized tetrahydrobiopterin, and we observed a significant decrease in plasma NOx (NO2 + NO3) levels in HCU mice. Additional impairment of NO generation may also come from the HCU-mediated induction of the 20-hydroxyeicosatetraenoic acid generating cytochrome CYP4A. Collectively, our data shows that HCU induces dysfunctional one-carbon metabolism with the potential to both impair betaine treatment and contribute to multiple aspects of pathogenesis in this disease.

Identification of Innovative Folate Inhibitors Leveraging the Amino Dihydrotriazine Motif from Cycloguanil for Their Potential as Anti-Trypanosoma brucei Agents.

Folate enzymes, namely, dihydrofolate reductase (DHFR) and pteridine reductase (PTR1) are acknowledged targets for the development of antiparasitic agents against Trypanosomiasis and Leishmaniasis. Based on the amino dihydrotriazine motif of the drug Cycloguanil (Cyc), a known inhibitor of both folate enzymes, we have identified two novel series of inhibitors, the 2-amino triazino benzimidazoles (1) and 2-guanidino benzimidazoles (2), as their open ring analogues. Enzymatic screening was carried out against PTR1, DHFR, and thymidylate synthase (TS). The crystal structures of TbDHFR and TbPTR1 in complex with selected compounds experienced in both cases a substrate-like binding mode and allowed the rationalization of the main chemical features supporting the inhibitor ability to target folate enzymes. Biological evaluation of both series was performed against T. brucei and L. infantum and the toxicity against THP-1 human macrophages. Notably, the 5,6-dimethyl-2-guanidinobenzimidazole 2g resulted to be the most potent (Ki = 9 nM) and highly selective TbDHFR inhibitor, 6000-fold over TbPTR1 and 394-fold over hDHFR. The 5,6-dimethyl tricyclic analogue 1g, despite showing a lower potency and selectivity profile than 2g, shared a comparable antiparasitic activity against T. brucei in the low micromolar domain. The dichloro-substituted 2-guanidino benzimidazoles 2c and 2d revealed their potent and broad-spectrum antitrypanosomatid activity affecting the growth of T. brucei and L. infantum parasites. Therefore, both chemotypes could represent promising templates that could be valorized for further drug development.

Enzoology: understanding enzyme interactions and epistasis in the cell.

Recent work from Nguyen et al. unveils massively parallel measurements of epistatic interactions between two enzymes, dihydrofolate reductase and thymidylate synthase, in their natural cellular context. Almost 3000 mutations of DHFR in three TYMS backgrounds reveal a complex interaction network. The authors capture much of this complexity using a simple model.

Construction and Docking Studies of Novel Pyrimido[4,5-b]quinolines as Antimicrobial Agents.

In order to develop novel antimicrobial agents, we prepared quinoline bearing pyrimidine analogues 2-7, 8 a-d and 9 a-d and their structures were elucidated by spectroscopic techniques. Furthermore, our second aim was to predict the interactions between the active compounds and enzymes (DNA gyrase and DHFR). In this work, fourteen pyrimido[4,5-b]quinoline derivatives were prepared and assessed for their antimicrobial potential by estimating zone of inhibition. All the screened candidates displayed antibacterial potential with zone of inhibition range of 9-24 mm compared with ampicillin (20-25 mm) as a reference drug. Moreover, the target derivatives 2 (ZI=16), 9 c (ZI=17 mm) and 9 d (ZI=16 mm) recorded higher antifungal activity against C. albicans to that exhibited by the antifungal drug amphotericin B (ZI=15 mm). Finally, the most potent pyrimidoquinoline compounds (2, 3, 8 c, 8 d, 9 c and 9 d) were docked inside DHFR and DNA gyrase active sites and they recorded excellent fitting within the active regions of DNA gyrase and DHFR. These outcomes revealed us that compounds (2, 3, 8 c, 8 d, 9 c and 9 d) could be lead compounds to discover novel antibacterial candidates.

Revisiting methotrexate and phototrexate Zinc15 library-based derivatives using deep learning in-silico drug design approach.

Introduction: Cancer is the second most prevalent cause of mortality in the world, despite the availability of several medications for cancer treatment. Therefore, the cancer research community emphasized on computational techniques to speed up the discovery of novel anticancer drugs. Methods: In the current study, QSAR-based virtual screening was performed on the Zinc15 compound library (271 derivatives of methotrexate (MTX) and phototrexate (PTX)) to predict their inhibitory activity against dihydrofolate reductase (DHFR), a potential anticancer drug target. The deep learning-based ADMET parameters were employed to generate a 2D QSAR model using the multiple linear regression (MPL) methods with Leave-one-out cross-validated (LOO-CV) Q2 and correlation coefficient R2 values as high as 0.77 and 0.81, respectively. Results: From the QSAR model and virtual screening analysis, the top hits (09, 27, 41, 68, 74, 85, 99, 180) exhibited pIC50 ranging from 5.85 to 7.20 with a minimum binding score of -11.6 to -11.0 kcal/mol and were subjected to further investigation. The ADMET attributes using the message-passing neural network (MPNN) model demonstrated the potential of selected hits as an oral medication based on lipophilic profile Log P (0.19-2.69) and bioavailability (76.30% to 78.46%). The clinical toxicity score was 31.24% to 35.30%, with the least toxicity score (8.30%) observed with compound 180. The DFT calculations were carried out to determine the stability, physicochemical parameters and chemical reactivity of selected compounds. The docking results were further validated by 100 ns molecular dynamic simulation analysis. Conclusion: The promising lead compounds found endorsed compared to standard reference drugs MTX and PTX that are best for anticancer activity and can lead to novel therapies after experimental validations. Furthermore, it is suggested to unveil the inhibitory potential of identified hits via in-vitro and in-vivo approaches.

Quassinoids from Eurycoma longifolia as Potential Dihydrofolate Reductase Inhibitors: A Computational Study.

BACKGROUND: Quassinoids are degraded triterpene compounds that can be obtained from various species of the Simaroubaceae plant family, including Eurycoma longifolia. Quassinoids are the major compounds in E. longifolia, and they are known to have various medicinal potentials, such as anticancer and antimalarial properties. Dihydrofolate reductase (DHFR) was reported to be one of the important targets for certain anticancer and antimalarial drugs. Twelve quassinoids from E. longifolia were identified to have anticancer effects based on their IC50 values. This study aimed to evaluate the interactions of these twelve quassinoids with DHFR via Autodock 4.2 software and Biovia Discovery Studio Visualiser. METHODS: Twelve quassinoids from E. longifolia and their interactions with DHFR were evaluated via Autodock 4.2 software and Biovia Discovery Studio Visualiser. Their drug-likeness and pharmacokinetic properties were also assessed using the ADMETlab 2.0 program. RESULTS: The molecular docking results showed that eleven quassinoids showed better docking scores than methotrexate, in which the binding energy (BE) of these quassinoids ranged from - 7.87 to -9.58 kcal/mol. Their inhibition constant (Ki) ranged from 0.095 to 1.71 µM. At the same time, the BE and Ki values for methotrexate were -7.80 kcal/mol and 1.64 µM, respectively. CONCLUSION: From the analysis, 6-dehydrolongilactone and eurycomalide B are among the twelve compounds that showed great potential as hit-to-lead compounds based on the docking score on DHFR, drug-likeness, and ADMET properties. These results suggest a great potential to pursue validation studies via in vitro and in vivo models.

Prevalence of polymorphisms in marker genes associated with antimalarial drug resistance in Plasmodium falciparum following 10 years of artemisinin-based combination therapy implementation in urban Kolkata.

Context: Resistance to antimalarial drugs is one of the major challenges for malaria elimination. In India, artemisinin combination therapy (artesunate-sulfadoxin pyrimethamine) was introduced in place of chloroquine (CQ) for the treatment of uncomplicated falciparum malaria in 2010. Periodical monitoring of polymorphisms in antimalarial drug resistance marker genes will be useful for assessing drug pressure, mapping and monitoring of drug resistance status; and will be helpful for searching alternative treatments. Objectives: This study was conducted to study the polymorphisms in antimalarial drug resistance marker genes among clinical Plasmodium falciparum isolates collected from Kolkata after 10 years of artemisinin-based combination therapie (ACT) implementation. Materials and Methods: Blood samples were collected from P. falciparum mono-infected patients and polymorphisms in P. falciparum CQ resistance transporter (pfcrt), P. falciparum multidrug resistance (pfmdr-1), P. falciparum dihydrofolate reductase (pfdhfr), P. falciparum dihydropteroate synthetase (pfdhps), pfATPase6 and pfK-13 propeller genes were analysed by polymerase chain reaction and DNA sequencing. Results: In pfcrt gene, C72S, and K76T mutation was recorded in 100% isolates and no mutations was detected in any of the targeted codons of pfmdr-1 gene. A double mutant pfcrt haplotype SVMNT and wildtype haplotype NYD in pfmdr-1 were prevalent in 100% of study isolates. Triple mutant pfdhfr-pfdhps haplotype ANRNI-SGKAA was recorded. No polymorphism in pfK13 gene was documented in any of the isolates. Conclusions: Observed wild codon N86 along with Y184 and D1246 of pfmdr-1 gene might be an indication of the reappearance of CQ sensitivity. The absence of quadruple and quintuple haplotypes in pfdhfr-pfdhps gene along with the wild haplotype of pfK13 is evidence of ACT effectivity. Hence, similar studies with large sample size are highly suggested for monitoring the drug resistance status of P. falciparum.

Ubiquitylation-independent cotranslational degradation of dihydrofolate reductase and ubiquitin.

Nascent proteins are degraded during or immediately after synthesis, a process called cotranslational protein degradation (CTPD). Although CTPD was observed decades ago, it has never been fully explored mechanistically and functionally. We show here that dihydrofolate reductase (DHFR) and ubiquitin (Ub), two stable proteins widely used in protein degradation studies, are actually subject to CTPD. Unlike canonical posttranslational protein degradation, CTPD of DHFR and Ub does not require prior ubiquitylation. Our data also suggest that protein expression level and N-terminal folding pattern may be two critical determinants for CTPD. Thus, this study reveals that CTPD plays a role in regulating the homeostasis of long-lived proteins and provides insights into the mechanism of CTPD.

Maternal exposure to folate antagonists and susceptibility to congenital heart disease in offspring: A systematic review and meta-analysis.

AIMS: The objective of this meta-analysis was to determine whether maternal exposure to folate antagonists is associated with increased rates of congenital heart disease in offspring. METHODS: A comprehensive search for articles in the MEDLINE (PubMed) and EMBASE databases published up to 21 August 2023 was performed. The search strategy was not limited by study design but only for articles in the English language. RESULTS: Analysis of 6 cohort studies and 5 cross-sectional studies, published between 1976 and 2020, showed significant increase in rate of congenital heart disease (odds ratio 1.55, 95% confidence interval, 1.28-1.87) when exposed to folate antagonists compared with the control. Further subgroup analysis showed the increased rate for exposure to both dihydrofolate reductase inhibitors and antiepileptic drugs separately. No differences were observed when analyses were stratified by timing of study. CONCLUSION: Administration of folate antagonists within the 12-week period preceding conception and throughout the second and third months of gestation exhibited a statistically significant elevation in the susceptibility to congenital heart diseases. Notably, the protective effect of folic acid supplementation was reported in cases of congenital heart disease linked to dihydrofolate reductase inhibitors but not that associated with antiepileptic drugs.

Repurposing FDA-approved drugs to target malaria through inhibition of dihydrofolate reductase in the folate biosynthesis pathway: A prospective approach.

Dihydrofolate reductase (DHFR) is a ubiquitous enzyme that regulates the biosynthesis of tetrahydrofolate among various species of Plasmodium parasite. It is a validated target of the antifolate drug pyrimethamine (Pyr) in Plasmodium falciparum (Pf), but its clinical efficacy has been hampered due to the emergence of drug resistance. This has made the attempt to screen Food & Drug Administration-approved drugs against wild- and mutant PfDHFR by employing an in-silico pipeline to identify potent candidates. The current study has followed a virtual screening approach for identifying potential DHFR inhibitors from DrugBank database, based on a structure similarity search of candidates, followed by absorption, distribution, metabolism, and excretion estimation. The screened drugs were subjected to various parameters like docking, molecular mechanics with generalized born and surface area solvation calculations, and molecular simulations. We have thus identified two potential drug candidates, duloxetine and guanethidine, which can be repurposed to be tested for their efficacy against wild type and drug resistant falciparum malaria.

A discovery of potent kaempferol derivatives as multi-target medicines against diabetes as well as bacterial infections: an in silico approach.

Flavonoids demonstrate beneficial effects on human health because flavonoids contain important biological properties. Kaempferol is a flavonol, type of flavonoid found in eatable plants and in plants usually employed in ancient drugs (Moringa oleifera, Tilia spp., fern genus spp. and gingko etc.). Some medicinal studies have shown that the use of foods full of kaempferol decreases the risk of many (cancer, vascular) diseases. All the data of 50 kaempferol derivatives were collected from PubChem database. Through Schrödinger software, 3D-QSAR study was performed for 50 compounds by using method of field base. Conformer of kaempferol derivatives was docked against anti-diabetic, anti-microbial co-crystal structures and protein. To monitor the best anti-diabetic and antibacterial agent, particular kaempferol derivatives were downloaded from PubChem database. Virtual screening by molecular docking provided four lead compounds with four different proteins. These hit compounds were found to be potent inhibitor for diabetic enzymes alpha-amylase and DPP IV and had the potential to suppress DNA gyrase and dihydrofolate reductase synthesis. Molecular dynamic simulation of docked complexes evaluates the value of root mean square fluctuation by iMOD server. Kaempferol 3-O-alpha-L-(2, 3-di-Z-p-coumaroyl) rhamnoside (42) compound used as anti-diabetic and kaempferol 3-O-gentiobioside (3) as antibacterial with good results can be used for drug discovery.Communicated by Ramaswamy H. Sarma.

The Differential Translation Capabilities of the Human DHFR2 Gene Indicates a Developmental and Tissue-Specific Endogenous Protein of Low Abundance.

A functional role has been ascribed to the human dihydrofolate reductase 2 (DHFR2) gene based on the enzymatic activity of recombinant versions of the predicted translated protein. However, the in vivo function is still unclear. The high amino acid sequence identity (92%) between DHFR2 and its parental homolog, DHFR, makes analysis of the endogenous protein challenging. This paper describes a targeted mass spectrometry proteomics approach in several human cell lines and tissue types to identify DHFR2-specific peptides as evidence of its translation. We show definitive evidence that the DHFR2 activity in the mitochondria is in fact mediated by DHFR, and not DHFR2. Analysis of Ribo-seq data and an experimental assessment of ribosome association using a sucrose cushion showed that the two main Ensembl annotated mRNA isoforms of DHFR2, 201 and 202, are differentially associated with the ribosome. This indicates a functional role at both the RNA and protein level. However, we were unable to detect DHFR2 protein at a detectable level in most cell types examined despite various RNA isoforms of DHFR2 being relatively abundant. We did detect a DHFR2-specific peptide in embryonic heart, indicating that the protein may have a specific role during embryogenesis. We propose that the main functionality of the DHFR2 gene in adult cells is likely to arise at the RNA level.

In-silico evaluation of Bismurrayaquinone-A phytochemical as a potential multifunctional inhibitor targeting dihydrofolate reductase: implications for anticancer and antibacterial drug development.

Dihydrofolate reductase (DHFR) has gained significant attention in drug development, primarily due to marked distinctions in its active site among different species. DHFR plays a crucial role in both DNA and amino acid metabolism by facilitating the transfer of monocarbon residues through tetrahydrofolate, which is vital for nucleotide and amino acid synthesis. This considers its potential as a promising target for therapeutic interventions. In this study, our focus was on conducting a virtual screening of phytoconstituents from the IMPPAT2.0 database to identify potential inhibitors of DHFR. The initial criterion involved assessing the binding energy of molecules against DHFR and we screened top 20 compounds ranging energy -13.5 to -11.4 (kcal/Mol) while Pemetrexed disodium bound with less energy -10.2 (kcal/Mol), followed by an analysis of their interactions to identify more effective hits. We prioritized IMPHY007679 (Bismurrayaquinone-A), which displayed a high binding affinity and crucial interaction with DHFR. We also evaluated the drug-like properties and biological activity of IMPHY007679. Furthermore, MD simulation was done, RMSD, RMSF, Rg, SASA, PCA and FEL explore the time-evolution impact of IMPHY007679 comparing it with a reference drug, Pemetrexed disodium. Collectively, our findings suggest that IMPHY007679 recommend further investigation in both in vitro and in vivo settings for its potential in developing anticancer and antibacterial therapies. This compound holds promise as a valuable candidate for advancing drug research and treatment strategies.Communicated by Ramaswamy H. Sarma.