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1.
Evol Bioinform Online ; 20: 11769343241240558, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38586439

RESUMO

Mycobacterium orygis, a subspecies of the Mycobacterium tuberculosis complex (MTBC), has emerged as a significant concern in the context of One Health, with implications for zoonosis or zooanthroponosis or both. MTBC strains are characterized by the unique insertion element IS6110, which is widely used as a diagnostic marker. IS6110 transposition drives genetic modifications in MTBC, imparting genome plasticity and profound biological consequences. While IS6110 insertions are customarily found in the MTBC genomes, the evolutionary trajectory of strains seems to correlate with the number of IS6110 copies, indicating enhanced adaptability with increasing copy numbers. Here, we present a comprehensive analysis of IS6110 insertions in the M. orygis genome, utilizing ISMapper, and elucidate their genetic consequences in promoting successful host adaptation. Our study encompasses a panel of 67 paired-end reads, comprising 11 isolates from our laboratory and 56 sequences downloaded from public databases. Among these sequences, 91% exhibited high-copy, 4.5% low-copy, and 4.5% lacked IS6110 insertions. We identified 255 insertion loci, including 141 intragenic and 114 intergenic insertions. Most of these loci were either unique or shared among a limited number of isolates, potentially influencing strain behavior. Furthermore, we conducted gene ontology and pathway analysis, using eggNOG-mapper 5.0, on the protein sequences disrupted by IS6110 insertions, revealing 63 genes involved in diverse functions of Gene Ontology and 45 genes participating in various KEGG pathways. Our findings offer novel insights into IS6110 insertions, their preferential insertion regions, and their impact on metabolic processes and pathways, providing valuable knowledge on the genetic changes underpinning IS6110 transposition in M. orygis.

2.
Int J Biol Macromol ; 267(Pt 1): 131326, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38569988

RESUMO

Aspartate kinase (AK), an enzyme from the Wolbachia endosymbiont of Brugia malayi (WBm), plays a pivotal role in the bacterial cell wall and amino acid biosynthesis, rendering it an attractive candidate for therapeutic intervention. Allosteric inhibition of aspartate kinase is a prevalent mode of regulation across microorganisms and plants, often modulated by end products such as lysine, threonine, methionine, or meso-diaminopimelate. The intricate and diverse nature of microbial allosteric regulation underscores the need for rigorous investigation. This study employs a combined experimental and computational approach to decipher the allosteric regulation of WBmAK. Molecular Dynamics (MD) simulations elucidate that ATP (cofactor) and ASP (substrate) binding induce a closed conformation, promoting enzymatic activity. In contrast, the binding of lysine (allosteric inhibitor) leads to enzyme inactivation and an open conformation. The enzymatic assay demonstrates the optimal activity of WBmAK at 28 °C and a pH of 8.0. Notably, the allosteric inhibition study highlights lysine as a more potent inhibitor compared to threonine. Importantly, this investigation sheds light on the allosteric mechanism governing WBmAK and imparts novel insights into structure-based drug discovery, paving the way for the development of effective inhibitors against filarial pathogens.


Assuntos
Aspartato Quinase , Brugia Malayi , Simulação de Dinâmica Molecular , Wolbachia , Brugia Malayi/enzimologia , Brugia Malayi/microbiologia , Regulação Alostérica , Animais , Aspartato Quinase/metabolismo , Aspartato Quinase/genética , Aspartato Quinase/química , Simbiose , Trifosfato de Adenosina/metabolismo , Lisina/química , Lisina/metabolismo
3.
Indian J Microbiol ; 64(1): 36-47, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38468742

RESUMO

Tuberculosis (TB) is a major public health concern that results in significant morbidity and mortality, particularly in middle- to low-income countries. Extra-pulmonary tuberculosis (EPTB) in adults is a form of TB that affects organs other than the lungs and is challenging to diagnose and treat due to a lack of accurate early diagnostic markers and inadequate knowledge of host immunity. Next-generation sequencing-based approaches have shown potential for identifying diagnostic biomarkers and host immune responses related to EPTB. This strategic review discusses on the significance using primary human cells and cell lines for in vitro transcriptomic studies on common forms of EPTB, such as lymph node TB, brain TB, bone TB, and endometrial TB to derive potential insights. While organoids have shown promise as a model system, primary cell lines still remain a valuable tool for studying host-pathogen interplay due to their conserved immune system, non-iPSC origin, and lack of heterogeneity in cell population. This review outlines a basic workflow for researchers interested in performing transcriptomics studies in EPTB, and also discusses the potential of cell-line based dual RNA-Seq technology for deciphering comprehensive transcriptomic signatures, host-pathogen interplay, and biomarkers from the host and Mycobacterium tuberculosis. Thus, emphasizing the implementation of this technique which can significantly contribute to the global anti-TB effort and advance our understanding of EPTB.

4.
Toxicol Appl Pharmacol ; 485: 116904, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38503349

RESUMO

Manganese (Mn)-induced pulmonary toxicity and the underlying molecular mechanisms remain largely enigmatic. Further, in recent years, microRNAs (miRNAs) have emerged as regulators of several pollutants-mediated toxicity. In this context, our study aimed at elucidating whether miRNAs are involved in manganese (II) chloride (MnCl2) (Mn2+)-induced cytotoxicity in lung epithelial cells. Growth inhibition of Mn2+ towards normal human bronchial epithelial (BEAS-2B) and adenocarcinomic human alveolar basal epithelial (A549) cells was analyzed by MTT assay following 24 or 48 h treatment. Reactive oxygen species (ROS) generation, mitochondrial membrane potential (ΔΨm), cell cycle arrest, and apoptosis were evaluated by flow cytometry. RT-qPCR and Western blot were performed to analyze the expression of cyclins, anti-oxidant genes, and miRNAs. We used small RNA sequencing to investigate Mn2+-induced changes in miRNA expression patterns. In both cell lines, Mn2+ treatment inhibited growth in a dose-dependent manner. Further, compared with vehicle-treated cells, Mn2+ (250 µM) treatment induced ROS generation, cell cycle arrest, apoptosis, and decreased ΔΨm as well as altered the expression of cyclins and anti-oxidant genes. Sequencing data revealed that totally 296 miRNAs were differentially expressed in Mn2+-treated cells. Among them, miR-221-3p was one of the topmost down-regulated miRNAs in Mn2+-treated cells. We further confirmed this association in A549 cells. In addition, transient transfection was performed to study gain-of-function experiments. Forced expression of miR-221-3p significantly improved cell viability and reduced Mn2+-induced cell cycle arrest and apoptosis in BEAS-2B cells. In conclusion, miR-221-3p may be the most likely target that accounts for the cytotoxicity of Mn2+-exposed lung epithelial cells.


Assuntos
Apoptose , Células Epiteliais , Pulmão , MicroRNAs , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Células A549 , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Apoptose/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Pulmão/patologia , Pulmão/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Compostos de Manganês , Manganês/toxicidade , Linhagem Celular , Cloretos/toxicidade , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga
5.
J Biomol Struct Dyn ; : 1-18, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38344920

RESUMO

The biosynthetic arginine decarboxylase in Thermus thermophilus is responsible for producing spermidine, a polyamine with numerous biological applications in humans. The arginine decarboxylase has significant applications in biotechnology industries, suggesting the need to evaluate its biochemical and biophysical characteristics at the molecular level. In this study, both in vitro and in silico methods were employed to investigate the structural and functional behavior of the arginine decarboxylase protein. In in vitro, MALDI-TOF, size exclusion, and assay studies were performed to examine the nature and activity of the protein. The MALDI-TOF analysis confirmed the purified protein as biosynthetic arginine decarboxylase. The assay results revealed that the Pyridoxal 5'-Phosphate (PLP) cofactor plays a crucial role in enhancing enzyme activity by producing agmatine (a by-product of spermidine). Further, optimum enzyme activity was observed at 50 °C, suggesting the extremophilic nature of the enzyme. Unlike other proteins, this enzyme displayed optimal activity at both acidic and basic pH, demonstrating its sensitivity to pH changes. Furthermore, the addition of divalent ions like Mg 2+ increased the rate of reaction. In in silico, structure modeling, and comparative molecular dynamics simulation studies were used to assess the protein stability and behavior at different pH and temperature conditions. The findings of this study could be applied to improve enzyme production in the industry.Communicated by Ramaswamy H. Sarma.

6.
J Biomol Struct Dyn ; 42(4): 2058-2074, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37599457

RESUMO

The malarial parasite Plasmodium falciparum predominantly causes severe malaria and deaths worldwide. Moreover, resistance developed by P. falciparum to frontline drugs in recent years has markedly increased malaria-related deaths in South Asian Countries. Ribulose 5-phosphate and NADPH synthesized by Pentose Phosphate Pathway (PPP) act as a direct precursor for nucleotide synthesis and P. falciparum survival during oxidative challenges in the intra-erythrocytic growth phase . In the present study, we have elucidated the structure and functional characteristics of 6-phosphogluconate dehydrogenase (6PGD) in P. falciparum and have identified potent hits against 6PGD by pharmacophore-based virtual screening with ZINC and ChemBridge databases. Molecular docking and Molecular dynamics simulation, binding free energies (MMGBSA & MMPBSA), and Density Functional Theory (DFT) calculations were integratively employed to validate and prioritize the most potential hits. The 6PGD structure was found to have an open and closed conformation during MD simulation. The apo form of 6PGD was found to be in closed conformation, while a open conformation attributed to facilitating binding of cofactor. It was also inferred from the conformational analysis that the small domain of 6PGD has a high influence in altering the conformation that may aid in open/closed conformation of 6PGD. The top three hits identified using pharmacophore hypotheses were ChemBridge_11084819, ChemBridge_80178394, and ChemBridge_17912340. Though all three hits scored a high glide score, MMGBSA, and favorable ADMET properties, ChemBridge_11084819 and ChemBrdige_17912340 showed higher stability and binding free energy. Moreover, these hits also featured stable H-bond interactions with the active loop of 6PGD with binding free energy comparable to substrate-bound complex. Therefore, the ChemBridge_11084819 and ChemBridge_17912340 moieties demonstrate to have high therapeutic potential against 6PGD in P. falciparum.Communicated by Ramaswamy H. Sarma.


Assuntos
Malária , Plasmodium falciparum , Humanos , Simulação de Acoplamento Molecular , Plasmodium falciparum/metabolismo , Fosfogluconato Desidrogenase/metabolismo , Conformação Molecular
7.
Int J Biol Macromol ; 258(Pt 1): 128899, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38141706

RESUMO

Paraoxonase 2 (PON2) is an intracellular anti-oxidant protein ubiquitously expressed in all cells and reduces reactive oxygen species, endoplasmic reticulum (ER) stress, further improves mitochondrial function and thereby shows anti-apoptotic function. In diabetes and its complications this PON gets glycated and becomes in effective. The PON activity is reported to be reduced in diabetic retinopathy and we have earlier showed Carboxy methyl lysine (AGE) decreased PON2 expression and activity in Human retinal endothelial cells (HREC) . In this study, we have designed and developed a mutated PON2 by in silico and in vitro approach which can resist glycation. Where in glycation-prone residues in PON2 was predicted using in silico analyses and a mutated PON2 was developed using in vitro site directed mutagenesis (SDM) assay mPON2 (mutant PON2-PON2-K70A) and its efficacy was compared with wPON2 (wild type PON2). CML glycated wPON2 and reduced its activity when compared with mPON2 in HREC confirmed by immunoprecipitation and in vitro experiments. Additionally, mPON2 interaction efficiency with its substrates was higher than wPON2 by insilico assay and demonstrated enhanced inhibition against CML-induced oxidative stress, ER stress, pro-inflammation, and mitochondrial fission than wPON2 by invitro assay. Further mPON2 showed increased inhibition of phosphorylation of NFĸB induced by CML. Our investigation establishes that the over expression of mPON2 in HREC can defy glycation and therefore mitigate ER stress and inflammation against CML than endogenous wPON2. These findings imply that mPON2 can be a beneficial therapeutic target against diabetic retinopathy.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Humanos , Retinopatia Diabética/metabolismo , Células Endoteliais/metabolismo , Reação de Maillard , Arildialquilfosfatase/metabolismo , Estresse Oxidativo , Inflamação/metabolismo , Diabetes Mellitus/metabolismo
8.
J Biomol Struct Dyn ; : 1-18, 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38063080

RESUMO

The therapeutic potential of small molecule kinase inhibitors in cancer treatment is well recognized. However, achieving selectivity remains a formidable challenge, primarily due to the structural similarity of ATP binding pockets among kinases. Allosteric inhibition, which involves targeting binding pockets beyond the ATP-binding site, provides a promising alternative to overcome this challenge. In this study, a meticulous approach was implemented to prioritize type 3 inhibitors for LIMK2, employing a range of techniques including Molecular Dynamics (MD) simulations, e-pharmacophore-guided High Throughput Virtual Screening (HTVS), MM/GBSA and ADMETox analyses, Density Functional Theory (DFT) calculations, and MM/PBSA investigations. The e-pharmacophore model identifies a hypothesis featuring five essential pharmacophoric elements (RRRAH). Through virtual screening of the ZINC compound database, we identified only five compounds that align with all four pharmacophoric features: ZINC1044382792, ZINC1433610865, ZINC1044109145, ZINC952869440, and ZINC490621334. These compounds not only exhibit higher binding affinity but also demonstrate favorable ADME/Tox profiles. Molecular dynamics simulations underscore the stability of hydrogen bond interactions with critical cryptic LIMK2 pocket residues, Asp469 and Arg474, only for two compounds: ZINC143361086 and ZINC1044382792. These compounds also exhibit superior occupancy interactions, as indicated by HOMO-LUMO analysis. Additionally, binding free energy calculations highlight the significant affinities of these two compounds when complexed with LIMK2: -83.491 ± 1.230 kJ/mol and -90.122 ± 1.248 kJ/mol for ZINC1044382792 and ZINC1433610862, respectively. Hence, this comprehensive investigation identifies ZINC1433610862 and ZINC1044382792 as prospective hits, representing promising leads for targeting LIMK2 in cancer therapeutics.Communicated by Ramaswamy H. Sarma.

9.
J Biomol Struct Dyn ; : 1-19, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37811543

RESUMO

The present study was proposed to model full-length HBV-RT and investigate the intermolecular interactions of known inhibitor and libraries of phytocompounds to probe the potential natural leads by in silico and in vitro studies. Homology modeling of RT was performed by Phyre2 and Modeller and virtual screening of ligands implemented through POAP pipeline. Molecular dynamics (MD) simulation (100 ns) and MM-GBSA calculations were performed using Schrodinger Desmond and Prime, respectively. Phytocompounds probable host protein targets gene set pathway enrichment and network analysis were executed by KEGG database and Cytoscape software. Prioritized plant extracts/enriched fraction LC-MS analysis was performed and along with pure compound, RT inhibitory activity, time-dependent HBsAg and HBeAg secretion, and intracellular HBV DNA, and pgRNA by qRT-PCR was performed in HepG2.2.15 cell line. Among the screened chemical library of 268 phytocompounds from 18 medicinal plants, 15 molecules from Terminalia chebula (6), Bidens pilosa (5), and Centella asiatica (4)) were identified as potential inhibitors of YMDD and RT1 motif of HBV-RT. MD simulation demonstrated stable interactions of 15 phytocompounds with HBV-RT, of which 1,2,3,4,6-Pentagalloyl Glucose (PGG) was identified as lead molecule. Out of 15 compounds, 11 were predicted to modulate 39 proteins and 15 molecular pathways associated with HBV infection. TCN and TCW (500 µg/mL) showed potent RT inhibition, decreased intracellular HBV DNA, and pgRNA, and time-dependent inhibition of HBsAg and HBeAg levels compared to PGG and Tenofovir Disoproxil Fumarate. We propose that the identified lead molecules from T. chebula as promising and cost-effective moieties for the management of HBV infection.Communicated by Ramaswamy H. Sarma.

10.
Comput Biol Chem ; 107: 107942, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37673012

RESUMO

Tuberculosis (TB), caused by Mycobacterium tuberculosis (MTB), remains a major threat to global health, with the emergence of multi-drug and extensively drug-resistant strains posing a serious challenge. Thereby, understanding the molecular basis of MTB virulence and disease pathogenesis is critical for developing effective therapeutic strategies. Targeting proteins involved in central metabolism has been recognized as a promising therapeutic approach to combat MTB. In this regard, the enzyme AckA of the acetate metabolic pathway which produces acetate from acetyl phosphate, is an important drug target for various pathogenic organisms. Therefore, this study aimed to identify potential AckA inhibitors through in silico methods, including molecular modeling, molecular dynamics simulation (MDS), and high-throughput virtual screening (HTVS) followed by ADMETox, MMGBSA, Density Functional Theory (DFT) calculations. HTVS of one million compounds from the ZINC database against AckA resulted in the top five hits (ZINC82048449, ZINC1219737510, ZINC1771921358, ZINC119699567, and ZINC1427100376) with better binding affinity and optimal binding free energy. MDS studies on complexes revealed that key residues, Asn195, Asp266, Phe267, Gly314, and Asn318 played a significant role in stable interactions of the top-ranked compounds to AckA. These outcomes provide insights into the optimal binding of the leads to inhibit the acetate pathway and aid in the rational design of novel therapeutic agents. Thus, the identified leads may act as promising compounds for targeting AckA and may serve as a potential therapeutic modality for treating TB. Our findings offer valuable insights into the inhibition of the acetate pathway, while also serving as a blueprint for rational drug design. The identified leads hold promise as compelling compounds for targeting AckA, thereby offering a potential therapeutic avenue for tackling TB. Thus, our study uncovers a pathway toward promising TB therapeutics by elucidating AckA inhibitors. By leveraging in silico methodologies, potent compounds that hold the potential to thwart AckA's role in MTB's acetate pathway have been unveiled. This breakthrough fosters optimism in the quest for novel and effective TB treatments, addressing a global health challenge with renewed vigor.


Assuntos
Mycobacterium tuberculosis , Antituberculosos/química , Acetato Quinase/metabolismo , Simulação de Dinâmica Molecular , Acetatos
11.
Front Endocrinol (Lausanne) ; 14: 1177268, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37396188

RESUMO

Background: HNF1A is an essential component of the transcription factor network that controls pancreatic ß-cell differentiation, maintenance, and glucose stimulated insulin secretion (GSIS). A continuum of protein malfunction is caused by variations in the HNF1A gene, from severe loss-of-function (LOF) variants that cause the highly penetrant Maturity Onset Diabetes of the Young (MODY) to milder LOF variants that are far less penetrant but impart a population-wide risk of type 2 diabetes that is up to five times higher. Before classifying and reporting the discovered variations as relevant in clinical diagnosis, a critical review is required. Functional investigations offer substantial support for classifying a variant as pathogenic, or otherwise as advised by the American College of Medical Genetics and Genomics (ACMG) and the Association for Molecular Pathology (AMP) ACMG/AMP criteria for variant interpretation. Objective: To determine the molecular basis for the variations in the HNF1A gene found in patients with monogenic diabetes in India. Methods: We performed functional protein analyses such as transactivation, protein expression, DNA binding, nuclear localization, and glucose stimulated insulin secretion (GSIS) assay, along with structural prediction analysis for 14 HNF1A variants found in 20 patients with monogenic diabetes. Results: Of the 14 variants, 4 (28.6%) were interpreted as pathogenic, 6 (42.8%) as likely pathogenic, 3 (21.4%) as variants of uncertain significance, and 1 (7.14%) as benign. Patients harboring the pathogenic/likely pathogenic variants were able to successfully switch from insulin to sulfonylureas (SU) making these variants clinically actionable. Conclusion: Our findings are the first to show the need of using additive scores during molecular characterization for accurate pathogenicity evaluations of HNF1A variants in precision medicine.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , Medicina de Precisão , Alelos , Glucose , Fator 1-alfa Nuclear de Hepatócito/genética
12.
Lancet Reg Health Southeast Asia ; 14: 100205, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37193348

RESUMO

Background: The COVID-19 pandemic showcased the power of genomic sequencing to tackle the emergence and spread of infectious diseases. However, metagenomic sequencing of total microbial RNAs in wastewater has the potential to assess multiple infectious diseases simultaneously and has yet to be explored. Methods: A retrospective RNA-Seq epidemiological survey of 140 untreated composite wastewater samples was performed across urban (n = 112) and rural (n = 28) areas of Nagpur, Central India. Composite wastewater samples were prepared by pooling 422 individual grab samples collected prospectively from sewer lines of urban municipality zones and open drains of rural areas from 3rd February to 3rd April 2021, during the second COVID-19 wave in India. Samples were pre-processed and total RNA was extracted prior to genomic sequencing. Findings: This is the first study that has utilised culture and/or probe-independent unbiased RNA-Seq to examine Indian wastewater samples. Our findings reveal the detection of zoonotic viruses including chikungunya, Jingmen tick and rabies viruses, which have not previously been reported in wastewater. SARS-CoV-2 was detectable in 83 locations (59%), with stark abundance variations observed between sampling sites. Hepatitis C virus was the most frequently detected infectious virus, identified in 113 locations and co-occurring 77 times with SARS-CoV-2; and both were more abundantly detected in rural areas than urban zones. Concurrent identification of segmented virus genomic fragments of influenza A virus, norovirus, and rotavirus was observed. Geographical differences were also observed for astrovirus, saffold virus, husavirus, and aichi virus that were more prevalent in urban samples, while the zoonotic viruses chikungunya and rabies, were more abundant in rural environments. Interpretation: RNA-Seq can effectively detect multiple infectious diseases simultaneously, facilitating geographical and epidemiological surveys of endemic viruses that could help direct healthcare interventions against emergent and pre-existent infectious diseases as well as cost-effectively and qualitatively characterising the health status of the population over time. Funding: UK Research and Innovation (UKRI) Global Challenges Research Fund (GCRF) grant number H54810, as supported by Research England.

13.
Front Microbiol ; 14: 1152206, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37020719

RESUMO

The functional significance of the HIV-1 Antisense Protein (ASP) has been a paradox since its discovery. The expression of this protein in HIV-1-infected cells and its involvement in autophagy, transcriptional regulation, and viral latency have sporadically been reported in various studies. Yet, the definite role of this protein in HIV-1 infection remains unclear. Deciphering the 3D structure of HIV-1 ASP would throw light on its potential role in HIV lifecycle and host-virus interaction. Hence, using extensive molecular modeling and dynamics simulation for 200 ns, we predicted the plausible 3D-structures of ASP from two reference strains of HIV-1 namely, Indie-C1 (subtype-C) and NL4-3 (subtype-B) so as to derive its functional implication through structural domain analysis. In spite of sequence and structural differences in subtype B and C ASP, both structures appear to share common domains like the Von Willebrand Factor Domain-A (VWFA), Integrin subunit alpha-X (ITGSX), and ETV6-Transcriptional repressor, thereby reiterating the potential role of HIV-1 ASP in transcriptional repression and autophagy, as reported in earlier studies. Gromos-based cluster analysis of the centroid structures also reassured the accuracy of the prediction. This is the first study to elucidate a highly plausible structure for HIV-1 ASP which could serve as a feeder for further experimental validation studies.

14.
J Biomol Struct Dyn ; 41(24): 15177-15195, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36898858

RESUMO

Human DNA topoisomerase II alpha (hTopIIα) is a classic chemotherapeutic drug target. The existing hTopIIα poisons cause numerous side effects such as the development of cardiotoxicity, secondary malignancies, and multidrug resistance. The use of catalytic inhibitors targeting the ATP-binding cavity of the enzyme is considered a safer alternative due to the less deleterious mechanism of action. Hence, in this study, we carried out high throughput structure-based virtual screening of the NPASS natural product database against the ATPase domain of hTopIIα and identified the five best ligand hits. This was followed by comprehensive validation through molecular dynamics simulations, binding free energy calculation and ADMET analysis. On stringent multilevel prioritization, we identified promising natural product catalytic inhibitors that showed high binding affinity and stability within the ligand-binding cavity and may serve as ideal hits for anticancer drug development.Communicated by Ramaswamy H. Sarma.


Assuntos
Produtos Biológicos , DNA Topoisomerases Tipo II , Humanos , Ligantes , Simulação de Acoplamento Molecular , DNA Topoisomerases Tipo II/química , DNA Topoisomerases Tipo II/genética , DNA Topoisomerases Tipo II/metabolismo , Simulação de Dinâmica Molecular , Adenosina Trifosfatases/metabolismo
15.
Nat Prod Res ; 37(9): 1589-1593, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35007180

RESUMO

Blumea lacera (Burm.f.) DC. (Asteraceae) is used in the traditional system of medicine for the treatment of inflammation or irritable bowel disease (IBD). In this study, B. lacera was collected from different geographical regions and oil was extracted by hydro-distillation and further chemo-profiled using GC-FID-MS. The major compounds identified were 2,5-dimethoxy-p-cymene (28.7-0.4%), ß-caryophyllene (25.5-0.5%), carvotanacetone (24.5-0.4%), chrysanthenone (21.9-9.8%) and 2,6-dimethyl phenol (11.4-1.8%). The constituents of B. lacera also showed marked qualitative and quantitative variations. The percent chemical similarity was observed to be in the range of 51.7% to 59.2% between the localities. Moreover, molecular modelling, membrane molecular dynamics simulations, target prediction were implemented to decipher the potential targets relevant to IBD. This inferred that all these major compounds could be potential drug moieties for treating IBD in terms of targeting h5HTR3A, thereby substantiating the traditional use of B. lacera for the treatment of IBD ailments.


Assuntos
Asteraceae , Doenças Inflamatórias Intestinais , Óleos Voláteis , Humanos , Óleos Voláteis/química , Simulação de Acoplamento Molecular , Asteraceae/química , Cromatografia Gasosa-Espectrometria de Massas , Doenças Inflamatórias Intestinais/tratamento farmacológico
16.
Microbiol Resour Announc ; 12(1): e0079122, 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36541809

RESUMO

Here, we communicate the draft genome sequence of an ocular Mycobacterium tuberculosis strain (SNMICRO 2047-20) that was isolated from the vitreous fluid of a patient diagnosed with endophthalmitis. The genome sequence was 4,391,538 bp long with 3,898 protein-encoding genes and clustered to the East African-Indian lineage.

17.
J Biomol Struct Dyn ; 41(14): 6603-6615, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35971955

RESUMO

Laetiporus versisporus (Lloyd) Imazeki is an edible mushroom that grows abundantly in kodaikanal hills (India) during rainy season. Till now, there is a dearth of reports on chemoprofile and anticancer potential of this mushroom. In our recent study, L.versisporus ethanolic extract was reported to confer hepato-protective activity against DEN-induced HCC rats and also found to downregulate Bcl-2 activity. Moreover, the phytocompounds of a related species namely, L. sulphurous is also reported to potentially modulate Bcl-2 in glioblastoma. Hence, by this study, the bioactive compounds from L. versisporus ethanolic extract were profiled using LC-MS analysis and were virtually screened against ligand binding site of Bcl-2 in order to predict potential moieties with anticancer efficacies. Further, the top 3 potential hits were shortlisted based on MMGBSA score, ADME properties and stable complex formation during MD simulation. Amongst these hits, (6S)-1alpha, 25-dihydroxy vitaminD36,19-sulfurdioxide adduct was found to be highly promising in terms of binding affinity and ADME features comparable to the known inhibitor (DRO), thus shall be further probed for therapeutic efficacy using experimental validations for effective and natural mode of combating Bcl-2 mediated cancers.Communicated by Ramaswamy H. Sarma.


Chemoprofiling of Laetiporus versisporous ethanolic extract by LC-MS analysis.Anti-apoptotic Bcl-2 chosen as drug target based on documentation in similar Genus.Virtual screening of the profiled compounds vs. Bcl-2 inferred (6S)-1alpha, 25-dihydroxyvitamin D3 6,19-sulfur dioxide adduct as a potential novel inhibitor.This molecule also featured significant binding affinity and complex stability during MD comparable to DRO (known inhibitor).

18.
ACS Pharmacol Transl Sci ; 5(12): 1254-1266, 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36524010

RESUMO

Fibrosis is the primary factor influencing the prognosis of glaucoma post-trabeculectomy surgery, an eye condition characterized by increased intraocular pressure (IOP). Despite advancements in surgical procedures and aftercare, it continues to be a serious impediment. During the clinical intervention of scarring, fibrosis is managed by using topical application of combined antifibrotic drugs (mitomycin C). But still, scarring remains a key problem due to minimal drug penetration and nonbioavailability. In this study, we synthesized a cell-specific peptide for modulating scarring in human tenon fibroblasts undergoing epithelial-mesenchymal transition (EMT). The peptide was also conjugated with mitomycin C in order to investigate the effect of the drug conjugation on human tenon fibroblasts from the nanofiber composite system and to evaluate the fibrosis process. Peptide VRF2019 was identified using a subtractive proteomics approach, including solubility, cell penetration, and amphipathic properties. The peptide structure was determined using circular dichroism spectroscopy. The peptide and drug was conjugated using N-ethyl-N'-(3-(dimethylamino)propyl) carbodiimide/N-hydroxysuccinimide (EDC-NHS) chemistry, and the conjugation efficiency was evaluated using high-pressure liquid chromatography. The conjugated product and polycaprolactone (PCL) were electrospun to form a composite nanofiber, which was tested for cytotoxicity and drug release on human tenon fibroblast cells. The modeled VRF2019 peptide structure formed an α-helical structure with all residues spanning the allowed regions of the Ramachandran plot. Subsequent molecular dynamics simulations also demonstrated its membrane penetration potential. The peptide uptake was also studied in human tenon fibroblast cells. High-pressure liquid chromatography (HPLC) and mass spectrometry measurements confirmed peptide-drug conjugation and stability. Furthermore, scanning electron microscopy (SEM) investigation revealed the structure and size of the PCL composite nanofiber. We infer from early research that the PCL composite nanofiber matrix can greatly increase drug delivery and bioavailability.

19.
Front Med (Lausanne) ; 9: 1036874, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36465923

RESUMO

Peptide therapeutics have recently gained momentum in antiviral therapy due to their increased potency and cost-effectiveness. Interaction of the HIV-1 envelope gp120 with the host CD4 receptor is a critical step for viral entry, and therefore the CD4-binding site (CD4bs) of gp120 is a potential hotspot for blocking HIV-1 infection. The present study aimed to design short peptides from well-characterized CD4bs targeting broadly neutralizing antibodies (bNAbs), which could be utilized as bNAb mimetics for viral neutralization. Co-crystallized structures of HIV-1 gp120 in complex with CD4bs-directed bNAbs were used to derive hexameric peptides using the Rosetta Peptiderive protocol. Based on empirical insights into co-crystallized structures, peptides derived from the heavy chain alone were considered. The peptides were docked with both HIV-1 subtype B and C gp120, and the stability of the peptide-antigen complexes was validated using extensive Molecular Dynamics (MD) simulations. Two peptides identified in the study demonstrated stable intermolecular interactions with SER365, GLY366, and GLY367 of the PHE43 cavity in the CD4 binding pocket, and with ASP368 of HIV-1 gp120, thereby mimicking the natural interaction between ASP368gp120 and ARG59 CD4-RECEPTOR. Furthermore, the peptides featured favorable physico-chemical properties for virus neutralization suggesting that these peptides may be highly promising bNAb mimetic candidates that may be taken up for experimental validation.

20.
Exp Eye Res ; 223: 109194, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35868364

RESUMO

Diabetic Retinopathy is prevalent among patients with uncontrolled hyperglycemia resulting in vision loss. Despite numerous challenges to create a link among these conditions, the characterization of pathological neovascularization causing retinal damage due to the prognosis of early non-proliferative diabetic retinopathy to late proliferative diabetic retinopathy needs deep understanding. In this study, meta-analysis-based integration of gene expression datasets for the fibrovascular membrane of PDR and neural retina of NPDR were compared, to investigate the differentially expressed genes involved in retinal angiogenesis. Human samples with gene expression profiling of the same experiment type and platform with sufficient information for analysis were included in the study. The studies from cell lines and non-human studies, human samples that include serum, cornea, lens, and/or other ocular tissues or fluids, and studies that lack basic information for analysis were excluded. The microarray datasets available in the Gene Expression Omnibus database of the early and late stages in DR were screened to find common gene expression profiles. Using the INMEX bioinformatics tool, significantly upregulated and downregulated genes in the neural retina of Non-Proliferative Diabetic Retinopathy and fibrovascular membrane of Proliferative Diabetic Retinopathy were compared and studied by the combine effect size method. Using the STRING database PPI network, 50 upregulated and 50 downregulated genes were used to find the key candidate genes involved in retinal disease/degeneration in eye/retinal tissues. In the extensive gene expression meta-analysis performed using INMEX bioinformatics tool, overall, 7935 differentially expressed genes were identified and the respective heatmap was created by using the visualization tools of INVEX. STRING database PPI network identified Retinol Binding Protein 3, Neural Retina Leucine Zipper, S-Antigen Visual Arrestin, Peripherin 2, and Aryl Hydrocarbon Receptor Interacting Protein Like-1 to be the most highly ranked hub genes. The newly discovered potential genes related to retinal angiogenesis causing FVM formation in DR may provide insight into the cellular pathogenesis of NPDR to PDR.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Arrestinas/metabolismo , Diabetes Mellitus/metabolismo , Retinopatia Diabética/metabolismo , Expressão Gênica , Humanos , Neovascularização Patológica/metabolismo , Periferinas/metabolismo , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo , Retina/metabolismo , Proteínas de Ligação ao Retinol/metabolismo
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