Biotechnology and applied biochemistry最新文献

This study reports the synthesis and biological evaluation of four novel N-acetyl-derived heterocyclic compounds, namely 2-((1-acetyl-3-substituted-5-oxo-1,5-dihydro-4H-1,2,4-triazol-4-yl)iminomethyl)-phenyl-naphthalene-2-sulfonates. The compounds were synthesized via acetylation reactions using acetic anhydride and were fully characterized by IR, ¹H NMR, ^{1 3}C NMR, elemental analysis, and HR-MS techniques. The anticancer activities of the synthesized compounds were evaluated in the concentration range of 1.563-200 µM against HepG2 (hepatocellular carcinoma) and U87 (glioblastoma) cell lines, showing significant cytotoxic effects. Enzyme inhibition assays demonstrated potent inhibitory activities against α-glucosidase, α-amylase, acetylcholinesterase (AChE), and glutathione S-transferase (GST), with IC₅₀ values ranging from 1.4 to 2.9 µM. Molecular docking studies, performed using DFT-optimized geometries, supported the experimental findings and revealed strong and specific interactions with the target proteins. Among the studied derivatives, compound 2a exhibited the highest affinity toward α-glucosidase, 2d showed superior binding to α-amylase and AChE, while 2c demonstrated enhanced interaction with GST. Compound 2b displayed promising anticancer potential, forming stable complexes with proteins associated with the HepG2 and U87 cell lines.

Multidrug-resistant (MDR) microorganisms are widely recognized as a public health concern due to the antibiotic resistance, which is a major risk to global human health. Amino acids have been utilized to produce antimicrobial peptides as they are extremely effective and less likely to build microbial resistance. This study evaluates the efficacy of six aliphatic amino acids, isoleucine, methionine, valine, glycine, alanine, and proline against Pseudomonas aeruginosa. It is a Gram-negative MDR pathogen that utilizes N-acyl-homoserine lactones as signaling molecules to regulate the quorum sensing pathway and express virulence factors. The MIC and sub-MIC were determined by the broth dilution method. This finding reveals that isoleucine exhibits a higher inhibitory effect on the organism at MIC and sub-MIC concentration of amino acids compared to the inhibition by other amino acids. The biofilm production was inhibited at a higher percentage, and also EPS production was inhibited in treatment with isoleucine. Confocal laser scanning microscope results depicts the disintegration of biofilm formation upon treatment. The isoleucine-treated culture of P. aeruginosa effectively inhibits the toxic pyocyanin production. Pyoverdines play a crucial role in iron acquisition, and their production was found to be inhibited by isoleucine. Motility was observed by swimming and swarming, and the results obtained from the gene expression studies demonstrated that isoleucine, methionine, valine, and glycine inhibited more virulence gene expression compared to alanine and proline.

Antibiotic resistance, which renders existing antibiotics ineffective against bacterial infections, is among the top-most pressing global public health challenges. A promising strategy to combat bacterial infection without inducing the occurrence of drug resistance is by disrupting quorum sensing (QS)-a complex communication circuit that bacterial pathogens employ to regulate their virulence. Therefore, QS inhibitors have emerged in recent times as potential therapeutic agents against bacterial infections. S-Ribosylhomocysteinase (LuxS) is one particularly attractive target in the QS pathway, which synthesizes the signaling molecule that mediates interspecies bacterial communication called autoinducer-2 (AI-2). In this study, we used computational chemistry and drug discovery techniques, molecular docking, drug-likeness, toxicity prediction studies, and interaction profiling to identify bioactive phytochemicals from Annona muricata plant extract as potential anti-QS agents against LuxS. Screening a library of 123 natural acetogenins from A. muricata, we identified gigantetronenin and isoannonacin as promising LuxS inhibitors. The potential inhibitory activity of these compounds against LuxS suggests that they could be explored as QS inhibitors with broad-spectrum activity against bacterial pathogens. These findings highlight the potential of gigantetronenin and isoannonacin as novel therapeutic candidates for combating bacterial infections through QS inhibition.

L-arginine is a vital amino acid metabolized by L-arginase, an enzyme with growing biotechnological and therapeutic significance, particularly in cancer treatment. This study presents a comprehensive in silico characterization of the L-arginase gene isolated from Alcaligenes aquatilis BC2, a bacterium originating from Ethiopian soda lakes. The analysis identified a 336-amino-acid enzyme predicted to be stable, soluble, and extracellular. Homology modeling generated a reliable hexameric 3D structure with high stereochemical quality, validated through multiple structural assessment tools. Phylogenetic and conserved domain analyses confirmed the enzyme's evolutionary placement within the Alcaligenes genus and highlighted preserved functional motifs. Molecular docking predicted a strong binding affinity (-7.1 kcal mol^-1) for L-arginine, with ligand enzyme complex stabilized by a dense network of hydrogen bonds and electrostatic interactions within the active site. These findings elucidate the structural basis of the enzyme's function and underscore its potential for future experimental validation and therapeutic applications.

Acute myeloid leukemia (AML) is a rapidly progressing blood cancer with poor survival rates, necessitating aggressive treatment strategies like chemotherapy. Doxorubicin (DOXO) is commonly used but is limited by severe side effects, including myeloablation, which involves the depletion of bone marrow cells leading to immunosuppression and heightened infection risk. This study explores the potential of omega-3 polyunsaturated fatty acids (n-3 PUFAs), specifically docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), to enhance the efficacy of DOXO against AML cells while mitigating some of its toxicities. The results show that DHA and EPA increase the DOXO-induced apoptosis in KG1a cells and greater accumulation in the sub-G1 phase, suggesting enhanced cell death. TUNEL assays confirmed increased DNA fragmentation, whereas mRNA analysis revealed upregulation of apoptosis and cell cycle regulation genes. Importantly, DHA and EPA also reduced the hemolytic activity of DOXO, suggesting a protective effect against chemotherapy-associated side effects. These findings suggest that DHA and EPA could enhance the anti-leukemic impact of DOXO, potentially reducing the need for high-dose chemotherapy and alleviating risks like myeloablation, offering a promising adjunct strategy for AML treatment.

α-Galactosidase enzymes have a variety of applications in numerous areas, including medicine, energy, food, feed, prebiotics, and paper pulp production. A single α-galactosidase gene was identified in the Geobacillus kaustophilus genome through the analysis of the carbohydrate-active enzymes (CAZY) database. The objective of this study was to clone, express heterologously, purify, and biochemically characterize the α-galactosidase enzyme encoded in the G. kaustophilus genome. In order to achieve this, a codon-optimized synthetic gene encoding the α-galactosidase enzyme was cloned into the pQE30 plasmid and expressed in Escherichia coli BL21 DE3 pLysS. The biochemical characterization of G. kaustophilus α-galactosidase revealed that the purified enzyme exhibited optimal activity at 40°C and pH 6.0 in citrate buffer, with demonstrable activity over a broad range of pH and temperature. Furthermore, the GKαGal enzyme exhibited a V_max value of 41.09 U/mg and a 0.248 mM K_m value towards 4-nitrophenyl-α-d-galactopyranoside (pNPGal). In essence, the produced α-galactosidase enzyme has potential applications in the degradation of lignocellulosic biomass, disaccharides production, and in medical contexts.

Leukemia continues to provide a significant therapeutic challenge due to relapse, medication resistance, and treatment-associated toxicity, which frequently hinder sustained disease management. Rhizomes of ginger (Zingiber officinale) possess bioactive phenolics, notably 6-gingerol and 6-shogaol derivatives, which have demonstrated antileukemia efficacy in preclinical models. This study rigorously assesses the evidence regarding ginger-derived preparations and isolated compounds in both acute and chronic leukemia models, focusing on recurring mechanisms and translational viability. In leukemia cell line investigations and sparse resistant-model data, ginger-related interventions are consistently linked to diminished viability and the induction of mitochondrial apoptosis, typically indicated by alterations in Bax/Bcl-2 ratios, PARP breakage, and caspase-related measurements. Numerous studies indicate redox modulation, often characterized by elevated intracellular reactive oxygen species in leukemic cells, coupled with diminished pro-survival signaling, such as PI3K/Akt, as indicated by decreased pAkt and survivin levels. The suggested immunomodulatory and anti-inflammatory effects, encompassing alterations in NK-cell activity and cytokines like TNF-α and IL-6, are inadequately substantiated within leukemia-specific immunological contexts. Interpretation is limited by the variability in extract composition and chemical characterisation, inconsistent dose and exposure circumstances, dependence on endpoint markers without causative manipulation, and a lack of leukemia-specific clinical data. Ginger-derived compounds exhibit multi-target biological activity that necessitates further exploration through standardized and chemically defined preparations, pharmacokinetic and pharmacodynamic characterization, clinically relevant exposure benchmarks, and meticulously designed leukemia-focused translational and early-phase clinical studies to elucidate safety, efficacy, and compatibility with current therapies.

Ovarian Cancer is a leading cause of mortality among women globally, primarily due to lack of specific and sensitive early-stage diagnostic tools. This study aims to identify hub genes associated with recurrent, late-stage, and metastatic tumors as potential prognostic biomarkers and drug targets. Gene expression data from eight National Center for Biotechnology Information (NCBI)-Gene Expression Omnibus (GEO) datasets were categorized by recurrence, tumor-stage, and metastasis. Differential gene expression and enrichment analyses were performed. Hub genes were identified by protein-protein interaction networks and validated by the University of Alabama at Birmingham Cancer Data Analysis Portal (UALCAN), GEPIA2, pROC, and Kaplan-Meier plotter databases. Genetic alterations, immune cell infiltration, miRNA prediction, and drug-gene interactions were assessed using cBioPortal, CIBERSORTx, Encyclopedia of RNA Interactomes (ENCORI), and Drug-Gene Interaction Database (DGIdb), respectively. Eight hub genes (FN1, COL1A1, COL1A2, COL3A1, POSTN, LUM, IGF1, and CXCL8) were identified, with COL1A2 common across all tumor categories. Note that 19.6% of cases showed mutations in these genes, primarily COL3A1. Overexpression of most hub genes and reduced expression of CXCL8 correlated with worse survival outcomes. COL1A1 and FN1 showed strong diagnostic ability. Late-stage tumors showed elevated M2 macrophages and neutrophils. hsa-miR-29a-3p, hsa-miR-29b-3p, and hsa-miR-29c-3p were identified as the most interactive miRNAs. Ocriplasmin and pamidronate were identified as potential therapeutics. Our findings highlight the therapeutic relevance of these hub genes and identify them as potential drug targets and prognostic biomarkers in ovarian cancer.

We present a novel, cost-effective sensor for carcinoembryonic antigen (CEA) detection utilizing a pencil graphite electrode (PGE) in combination with electrochemical impedance spectroscopy (EIS), which offers high sensitivity and selectivity. Anti-CEA/AuNPs/PGE was successfully illustrated as a label-free impedimetric immunosensor for the detection of CEA. Through EIS, we observed distinct impedance changes upon CEA binding, enabling real-time detection with high reproducibility and low interference from non-target molecules. Due to its satisfying impedimetric response, this new immunosensor demonstrated that it can be used for high-performance detection of CEA with a wide linear range extending from 13.2 to 1 × 10⁵ pg mL^-1, with correlation coefficients (R²) of 0.9923. The PGE's excellent conductive properties and surface stability allowed for the successful detection of CEA at low concentrations, demonstrating a detection limit of 4.4 pg mL^-1, which is competitive with existing, more costly alternatives. The sensor's robust performance in spiked artificial urine samples indicates its potential for practical application in point-of-care cancer diagnostics, especially in resource-limited environments. The developed electrochemical biosensor holds promise for accurately detecting CEA in urine samples, offering a precise technique that could find valuable application in clinical tumor detection.

Multidrug-resistant tumor cells pose significant challenges in cancer treatment. Alternative strategies such as targeted gene silencing and the use of compounds with minimal cytotoxicity toward normal cells are therefore of great interest. Antimicrobial peptides (AMPs) have demonstrated anticancer potential due to their physicochemical properties. In lung cancer, overexpression of AKT serine/threonine kinase 1 (AKT1) promotes abnormal tumor growth and progression. In this study, we synthesized chitosan-based nanoparticles (CSNPs) co-loaded with Pseudomonas aeruginosa peptide from strain P3 (PAP3) (an AMP) and siRNA targeting the AKT1 gene, and evaluated their anticancer activity at the cellular and molecular levels. Characterization of the CSNPs revealed a nanoscale structure, low polydispersity index, and moderate encapsulation efficiency for both peptide and siRNA. Evaluation using L929 cells confirmed PAP3's nontoxic profile, while a dose-dependent anticancer effect against A549 cells was observed. Delivery of encapsulated peptide, siRNA, and their combination increased cell death and induced morphological changes in A549 cells. Gene expression analysis showed upregulation of pro-apoptotic markers (Bax and Caspase-3) and downregulation of the anti-apoptotic marker Bcl2, indicating promising anticancer properties of the engineered compound. In conclusion, co-delivery of PAP3 and AKT1-targeting siRNA via CSNPs demonstrates potential for future anticancer therapies.