RESUMEN
This study investigates the synthesis and optimization of nanobots (NBs) loaded with pDNA using the layer-by-layer (LBL) method and explores the impact of their collective motion on the transfection efficiency. NBs consist of biocompatible and biodegradable poly(lactic-co-glycolic acid) (PLGA) nanoparticles and are powered by the urease enzyme, enabling autonomous movement and collective swarming behavior. In vitro experiments were conducted to validate the delivery efficiency of fluorescently labeled NBs, using two-dimensional (2D) and three-dimensional (3D) cell models: murine urothelial carcinoma cell line (MB49) and spheroids from human urothelial bladder cancer cells (RT4). Swarms of pDNA-loaded NBs showed enhancements of 2.2- to 2.6-fold in delivery efficiency and 6.8- to 8.1-fold in material delivered compared to inhibited particles (inhibited enzyme) and the absence of fuel in a 2D cell culture. Additionally, efficient intracellular delivery of pDNA was demonstrated in both cell models by quantifying and visualizing the expression of eGFP. Swarms of NBs exhibited a >5-fold enhancement in transfection efficiency compared to the absence of fuel in a 2D culture, even surpassing the Lipofectamine 3000 commercial transfection agent (cationic lipid-mediated transfection). Swarms also demonstrated up to a 3.2-fold enhancement in the amount of material delivered in 3D spheroids compared to the absence of fuel. The successful transfection of 2D and 3D cell cultures using swarms of LBL PLGA NBs holds great potential for nucleic acid delivery in the context of bladder treatments.
Asunto(s)
ADN , Nanopartículas , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Humanos , Animales , Ratones , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Línea Celular Tumoral , Nanopartículas/química , ADN/química , ADN/metabolismo , Transfección/métodos , Ureasa/metabolismo , Ureasa/química , Ureasa/genética , Plásmidos/metabolismo , Plásmidos/genética , Plásmidos/química , Técnicas de Transferencia de Gen , Ácido Poliglicólico/química , Ácido Láctico/química , Neoplasias de la Vejiga Urinaria/metabolismo , Neoplasias de la Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/terapiaRESUMEN
Several novel copper (II) complexes of reduced Schiff bases containing fluoride substituents were prepared and structurally characterized by single-crystal X-ray diffraction. The complexes exhibited diverse structures, with the central atom in distorted tetrahedral geometry. The biological effects of the products were evaluated, specifically their cytotoxicity, antimicrobial, and antiurease activities, as well as affinity for albumin (BSA) and DNA (ct-DNA). The complexes showed marked cytotoxic activities in the HepG2 hepatocellular carcinoma cell line, considerably higher than the standard cisplatin. The cytotoxicity depended significantly on the substitution pattern. The best activity was observed in the complex with a trifluoromethyl group in position 4 of the benzene ring-the dichloro[(±)-trans-N,N'-bis-(4-trifluoromethylbenzyl)-cyclohexane-1,2-diamine]copper (II) complex, whose activity (IC50 28.7 µM) was higher than that of the free ligand and markedly better than the activity of the standard cisplatin (IC50 336.8 µM). The same complex also showed the highest antimicrobial effect in vitro. The affinity of the complexes towards bovine serum albumin (BSA) and calf thymus DNA (ct-DNA) was established as well, indicating only marginal differences between the complexes. In addition, all complexes were shown to be excellent inhibitors of the enzyme urease, with the IC50 values in the lower micromolar region.
Asunto(s)
Antineoplásicos , Complejos de Coordinación , Cobre , Bases de Schiff , Humanos , Bases de Schiff/química , Bases de Schiff/farmacología , Cobre/química , Células Hep G2 , Complejos de Coordinación/farmacología , Complejos de Coordinación/química , Complejos de Coordinación/síntesis química , Antineoplásicos/farmacología , Antineoplásicos/química , Ligandos , Flúor/química , ADN/metabolismo , ADN/química , Albúmina Sérica Bovina/química , Ureasa/antagonistas & inhibidores , Ureasa/metabolismoRESUMEN
Urolithiasis, characterized by the formation of solid crystalline structures within the urinary tract, presents a significant global health burden with high recurrence rates and limited treatment efficacy. Recent research has identified various protein receptors and enzymes implicated in the pathogenesis of urolithiasis, offering potential targets for therapeutic intervention. Protein receptors such as the calcium-sensing receptor and vasopressin V2 receptor play crucial roles in regulating urinary calcium excretion and water reabsorption, respectively, influencing stone formation. Additionally, modulation of receptors like the angiotensin II receptor and aldosterone receptor can impact renal function and electrolyte balance, contributing to stone prevention. Furthermore, enzymes such as urease inhibitors and xanthine oxidase inhibitors offer targeted approaches to prevent the formation of specific stone types. This review discusses the potential of targeting these receptors and enzymes for the treatment of urolithiasis, exploring associated drugs and their mechanisms of action. Despite promising avenues for personalized and precision medicine approaches, challenges such as the need for robust clinical evidence and ensuring cost-effectiveness must be addressed for the translation of these interventions into clinical practice. By overcoming these challenges, receptor-targeted therapies and enzyme inhibitors hold promise for revolutionizing the management of urolithiasis and reducing its global burden.
Asunto(s)
Terapia Molecular Dirigida , Medicina de Precisión , Urolitiasis , Humanos , Urolitiasis/tratamiento farmacológico , Urolitiasis/metabolismo , Medicina de Precisión/métodos , Animales , Inhibidores Enzimáticos/uso terapéutico , Inhibidores Enzimáticos/farmacología , Ureasa/antagonistas & inhibidores , Ureasa/metabolismo , Receptores Sensibles al Calcio/metabolismo , Receptores Sensibles al Calcio/antagonistas & inhibidores , Xantina Oxidasa/antagonistas & inhibidores , Xantina Oxidasa/metabolismo , Receptores de Vasopresinas/metabolismoRESUMEN
Helicobacter pylori (H. pylori) is responsible for various chronic or acute diseases, such as stomach ulcers, dyspepsia, peptic ulcers, gastroesophageal reflux, gastritis, lymphoma, and stomach cancers. Although specific drugs are available to treat the bacterium's harmful effects, there is an urgent need to develop a preventive or therapeutic vaccine. Therefore, the current study aims to create a multi-epitope vaccine against H. pylori using lipid nanoparticles. Five epitopes from five target proteins of H. pylori, namely, Urease, CagA, HopE, SabA, and BabA, were used. Immunogenicity, MHC (Major Histocompatibility Complex) bonding, allergenicity, toxicity, physicochemical analysis, and global population coverage of the entire epitopes and final construct were carefully examined. The study involved using various bioinformatic web tools to accomplish the following tasks: modeling the three-dimensional structure of a set of epitopes and the final construct and docking them with Toll-Like Receptor 4 (TLR4). In the experimental phase, the final multi-epitope construct was synthesized using the solid phase method, and it was then enclosed in lipid nanoparticles. After synthesizing the construct, its loading, average size distribution, and nanoliposome shape were checked using Nanodrop at 280 nm, dynamic light scattering (DLS), and atomic force microscope (AFM). The designed vaccine has been confirmed to be non-toxic and anti-allergic. It can bind with different MHC alleles at a rate of 99.05%. The construct loading was determined to be about 91%, with an average size of 54 nm. Spherical shapes were also observed in the AFM images. Further laboratory tests are necessary to confirm the safety and immunogenicity of the multi-epitope vaccine.
Asunto(s)
Vacunas Bacterianas , Biología Computacional , Helicobacter pylori , Nanopartículas , Helicobacter pylori/inmunología , Nanopartículas/química , Vacunas Bacterianas/inmunología , Vacunas Bacterianas/química , Biología Computacional/métodos , Humanos , Proteínas Bacterianas/inmunología , Proteínas Bacterianas/química , Epítopos/inmunología , Epítopos/química , Simulación del Acoplamiento Molecular , Antígenos Bacterianos/inmunología , Antígenos Bacterianos/química , Infecciones por Helicobacter/prevención & control , Infecciones por Helicobacter/inmunología , Receptor Toll-Like 4/inmunología , Ureasa/inmunología , Ureasa/química , Inmunoinformática , LiposomasRESUMEN
A novel and sensitive fluorescence ratiometric method is developed for urea detection based on the pH-sensitive response of two fluorescent carbon dot (CD) systems: R-CDs/methyl red (MR) and NIR-CDs/Cu2+. The sensing mechanism involves breaking down urea using the enzyme urease, releasing ammonia and increasing pH. At higher pH, the fluorescence of NIR-CDs is quenched due to the enhanced interaction with Cu2+, while the fluorescence of R-CDs is restored as the acidic MR converts to its basic form, removing the inner filter effect. The ratiometric signal (F608/F750) of the R-CDs/MR and NIR-CDs/Cu2+ intensities changed in response to the pH induced by urea hydrolysis, enabling selective and sensitive urea detection. Detailed spectroscopic and morphological investigations confirmed the fluorescence probe design and elucidated the sensing mechanism. The method exhibited excellent sensitivity (0.00028 mM LOD) and linearity range (0.001 - 8.0 mM) for urea detection, with successful application in milk samples for monitoring adulteration, demonstrating negligible interference and high recovery levels (96.5% to 101.0%). This ratiometric fluorescence approach offers a robust strategy for selective urea sensing in complicated matrices.
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Carbono , Cobre , Colorantes Fluorescentes , Límite de Detección , Puntos Cuánticos , Espectrometría de Fluorescencia , Urea , Ureasa , Urea/análisis , Urea/química , Ureasa/química , Cobre/química , Carbono/química , Concentración de Iones de Hidrógeno , Puntos Cuánticos/química , Colorantes Fluorescentes/química , Espectrometría de Fluorescencia/métodos , Animales , Leche/química , Compuestos Azo/química , Contaminación de Alimentos/análisisRESUMEN
Emerging evidence suggests differential antagonism of lactic acid-producing bacteria (LAB) to Helicobacter pylori, posing challenges to human health and food safety due to unclear mechanisms. This study assessed 21 LAB strains from various sources on H. pylori growth, urease activity, and coaggregation. Composite scoring revealed that Latilactobacillus sakei LZ217, derived from fresh milk, demonstrates strong inhibitory effects on both H. pylori growth and urease activity. L. sakei LZ217 significantly reduced H. pylori adherence of gastric cells in vitro, with inhibition ratios of 47.62%. Furthermore, in vivo results showed that L. sakei LZ217 alleviated H. pylori-induced gastric mucosa damage and inflammation in mice. Metabolomic exploration revealed metabolic perturbations in H. pylori induced by L. sakei LZ217, including reduced amino acid levels (e.g., isoleucine, leucine, glutamate, aspartate, and phenylalanine) and impaired carbohydrate and nucleotide synthesis, contributing to the suppression of ureA (28.30%), ureE (84.88%), and ureF (59.59%) expressions in H. pylori. This study underscores the efficacy of LAB against H. pylori and highlights metabolic pathways as promising targets for future interventions against H. pylori growth and colonization.
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Mucosa Gástrica , Infecciones por Helicobacter , Helicobacter pylori , Ureasa , Ureasa/metabolismo , Animales , Infecciones por Helicobacter/microbiología , Mucosa Gástrica/microbiología , Mucosa Gástrica/metabolismo , Ratones , Humanos , Adhesión Bacteriana , Femenino , Probióticos , MasculinoRESUMEN
Urease is a metalloenzyme that contains two Ni(II) ions in its active site and catalyzes the hydrolysis of urea into ammonia and carbon dioxide. The development of effective urease inhibitors is crucial not only for mitigating nitrogen losses in agriculture but also for offering an alternative treatment against infections caused by resistant pathogens that utilize urease as a virulence factor. This study focuses on synthesizing and investigating the urease inhibition potential of Biginelli Adducts bearing a boric acid group. An unsubstituted or hydroxy-substituted boronic group in the Biginelli adducts structure enhances the urease inhibitory activity. Biophysical and kinetics studies revealed that the best Biginelli adduct (4e; IC50 = 132 ± 12 µmol/L) is a mixed inhibitor with higher affinity to the urease active site over an allosteric one. Docking studies confirm the interactions of 4e with residues essential for urease activity and demonstrate its potential to coordinate with the nickel atoms through the oxygen atoms of carbonyl or boronic acid groups. Overall, the Biginelli adduct 4e shows great potential as an additive for developing enhanced efficiency fertilizers and/or for medical applications.
Asunto(s)
Ácidos Borónicos , Inhibidores Enzimáticos , Ureasa , Ácidos Borónicos/química , Ácidos Borónicos/farmacología , Ácidos Borónicos/síntesis química , Canavalia/enzimología , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química , Simulación del Acoplamiento Molecular , Estructura Molecular , Relación Estructura-Actividad , Ureasa/antagonistas & inhibidores , Ureasa/metabolismo , Níquel/químicaRESUMEN
BACKGROUND: Theoretically, a rapid urease test (RUT) using a swab of the gastric wall (Swab-RUT) for Helicobacter pylori (H. pylori) is safe. However, the validity and utility of Swab-RUT remain unclear. Therefore, we assessed the validity and utility of Swab-RUT compared to RUT using mucosal forceps of the gastric wall (Forceps-RUT) and 13C-urea breath test (UBT). METHODS: This study was a multicenter prospective observational study. When the examinees were suspected of H. pylori infection during esophagogastroduodenoscopy, we performed Swab-RUT and Forceps-RUT continuously. When the examinees were not suspected of H. pylori infection, we performed Swab-RUT alone. We validated the status of H. pylori infection using UBT. RESULTS: Ninety-four examinees were enrolled from four institutions between May 2016 and December 2020 (median age [range], 56.5 [26-88] years). In this study, the sensitivity, specificity, and accuracy of Swab-RUT to UBT were 0.933 (95% confidence interval: 0.779-0.992), 0.922 (0.827-0.974), and 0.926 (0.853-0.970), respectively. The Kappa coefficient of Swab-RUT to UBT was 0.833, and that of Swab-RUT to forceps-RUT was 0.936. No complications were observed in this study. CONCLUSIONS: Swab-RUT is a valid examination for the status of H. pylori infection compared to the conventional Forceps-RUT.
Asunto(s)
Pruebas Respiratorias , Infecciones por Helicobacter , Helicobacter pylori , Sensibilidad y Especificidad , Ureasa , Humanos , Pruebas Respiratorias/métodos , Pruebas Respiratorias/instrumentación , Infecciones por Helicobacter/diagnóstico , Infecciones por Helicobacter/microbiología , Persona de Mediana Edad , Estudios Prospectivos , Ureasa/análisis , Ureasa/metabolismo , Masculino , Femenino , Anciano , Helicobacter pylori/aislamiento & purificación , Helicobacter pylori/enzimología , Adulto , Anciano de 80 o más Años , Mucosa Gástrica/microbiología , Endoscopía del Sistema Digestivo , Reproducibilidad de los Resultados , Isótopos de Carbono , Instrumentos Quirúrgicos/microbiologíaRESUMEN
BACKGROUND: Rhododendron delavayi is a natural shrub that is distributed at different elevations in the karst region of Bijie, China, and that has an important role in preventing land degradation in this region. In this study, we determined the soil mineral element contents and soil enzyme activities. The composition of the soil bacterial community of R. delavayi at three elevations (1448 m, 1643 m, and 1821 m) was analyzed by high-throughput sequencing, and the interrelationships among the soil bacterial communities, mineral elements, and enzyme activities were determined. RESULTS: The Shannon index of the soil bacterial community increased and then decreased with increasing elevation and was highest at 1643 m. Elevations increased the number of total nodes and edges of the soil bacterial community network, and more positive correlations at 1821 m suggested stronger intraspecific cooperation. Acidobacteria, Actinobacteria and Proteobacteria were the dominant phyla at all three elevations. The Mantel test and correlation analysis showed that Fe and soil urease significantly affected bacterial communities at 1448 m; interestingly, Chloroflexi was positively related to soil urease at 1448 m, and Actinobacteria was positively correlated with Ni and Zn at 1821 m. Fe and soil urease significantly influenced the bacterial communities at lower elevations, and high elevation (1821 m) enhanced the positive interactions of the soil bacteria, which might be a strategy for R. delavayi to adapt to high elevation environments. CONCLUSION: Elevation significantly influenced the composition of soil bacterial communities by affecting the content of soil mineral elements and soil enzyme activity.
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Bacterias , Bosques , Rhododendron , Microbiología del Suelo , Suelo , Suelo/química , Rhododendron/microbiología , China , Bacterias/clasificación , Bacterias/genética , Bacterias/enzimología , Bacterias/aislamiento & purificación , Metales/análisis , Actinobacteria/genética , Actinobacteria/enzimología , Actinobacteria/aislamiento & purificación , Actinobacteria/clasificación , Microbiota , Ureasa/metabolismo , Acidobacteria/genética , Acidobacteria/aislamiento & purificación , Acidobacteria/enzimología , Acidobacteria/clasificación , ARN Ribosómico 16S/genética , Filogenia , Secuenciación de Nucleótidos de Alto RendimientoRESUMEN
This work describes determining urea in milk samples using a multicommuted approach with a urease enzyme immobilized in bacterial cellulose and solid MOF as a colorimetric reagent. The Cu(2+)-MOF was characterized by FTIR spectroscopy, XRD, and SEM. The urea quantification was based on the urea hydrolysis reaction catalyzed by urease and reacted with Cu(2+)-MOF forming [Cu(NH3)4]2+, monitored at 450 nm. Linear responses were obtained from 1.0 to 50.0 mg dL-1 urea (R = 0.9959, n = 11), detection and quantitation limits of 0.082 mg dL-1 and 0.272 mg dL-1 respectively, analytical frequency of 8 determinations per hour, 0.8 mL sample solution consumption. Potential interfering studies have shown the selectivity of the proposed method. Addition and recovery tests were performed obtaining variation from 90 to 103%. Applying the F-test and t-test, the results showed no significant difference at the 95% confidence level Comparing the proposed and the reference method.
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Celulosa , Colorimetría , Cobre , Enzimas Inmovilizadas , Leche , Urea , Ureasa , Ureasa/química , Leche/química , Animales , Colorimetría/métodos , Enzimas Inmovilizadas/química , Celulosa/química , Cobre/química , Urea/química , Urea/análisis , Estructuras Metalorgánicas/química , Bovinos , Espectrofotometría , Bacterias/enzimología , Bacterias/química , Bacterias/aislamiento & purificaciónRESUMEN
Thirty protoberberine derivatives, of which twenty five were new, were synthesized and evaluated for their anti-Helicobacter pylori (HP) activities, taking 2,3,10-trimethoxy-9-p-methylbenzylaminoprotopalmatine chloride 1 as the lead. Among them, berberine (BBR) derivative 7c displayed the highest potency against six tested metronidazole (MTZ)-resistant strains and two tested MTZ-susceptible strains with the MIC values of 0.4-1.6 µg/mL with favorable druglike profiles including low toxicity and high stabilities in plasma and artificial gastric fluid. Mechanistic study revealed that 7c might target HP urease with IC50 value of 0.27 µg/mL against Jack bean urease. Furthermore, 7c might change the permeability of the bacterial membrane and direct interact with HP DNA, which also contribute to its bactericidal activity. Therefore, BBR derivatives constituted a new family of anti-HP candidates, with the advantage of good safety profile and multi-target mechanisms, and are worthy for further investigation.
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Antibacterianos , Berberina , Helicobacter pylori , Pruebas de Sensibilidad Microbiana , Helicobacter pylori/efectos de los fármacos , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/síntesis química , Berberina/farmacología , Berberina/química , Berberina/análogos & derivados , Berberina/síntesis química , Relación Estructura-Actividad , Estructura Molecular , Descubrimiento de Drogas , Relación Dosis-Respuesta a Droga , Ureasa/antagonistas & inhibidores , Ureasa/metabolismo , HumanosRESUMEN
We tested the ability of wood distillate (WD) to interact with urea in agricultural soil. WD is a sustainable material that has been addressed as a promising alternative to synthetic soil corroborants. However, there is little information about the effect of WD on the nitrogen cycle. In this study, soils with different amounts of WD and with/without urea were tested for ammonium, urease, nitrate/nitrite, and potential nitrification activity at different points in a 30 day time frame. High concentrations of WD (1-2%) inhibited the hydrolysis of urea and the oxidation of ammonium to nitrate. Thermal desorption coupled to GC-MS and high-performance liquid chromatography-tandem mass spectrometry characterization allowed us to reveal that WD-urea interactions mainly involve lignin-derived compounds in the distillate, such as catechol, resorcinol, and syringol. This study provides the first evidence of a strong interaction between WD and urea in soil that could be used to develop slow-release fertilizers.
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Fertilizantes , Madera , Madera/química , Urea/química , Urea/metabolismo , Ureasa/metabolismo , Cromatografía Líquida de Alta Presión , Cromatografía de Gases y Espectrometría de Masas , Nitrificación , Compuestos de Amonio/químicaRESUMEN
The clearance of urea poses a formidable challenge, and its excessive accumulation can cause various renal diseases. Urease demonstrates remarkable efficacy in eliminating urea, but cannot be reused. This study aimed to develop a composite vector system comprising microcrystalline cellulose (MCC) immobilized with urease and metal-organic framework (MOF) UiO-66-NH2, denoted as MCC@UiO/U, through the dynamic defect generation strategy. By utilizing competitive coordination, effective immobilization of urease into MCC@UiO was achieved for efficient urea removal. Within 2 h, the urea removal efficiency could reach up to 1500 mg/g, surpassing an 80% clearance rate. Furthermore, an 80% clearance rate can also be attained in peritoneal dialyzate from patients. MCC@UiO/U also exhibits an exceptional bioactivity even after undergoing 5 cycles of perfusion, demonstrating remarkable stability and biocompatibility. This innovative approach and methodology provide a novel avenue and a wide range of immobilized enzyme vectors for clinical urea removal and treatment of kidney diseases, presenting immense potential for future clinical applications.
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Celulosa , Enzimas Inmovilizadas , Estructuras Metalorgánicas , Urea , Ureasa , Ureasa/química , Ureasa/metabolismo , Urea/química , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Celulosa/química , Estructuras Metalorgánicas/química , HumanosRESUMEN
Microbially induced carbonate precipitation (MICP) is a common biomineralization method, which is often used for remediation of heavy metal pollution such as hexavalent chromium (Cr(VI)) in recent years. Calcium sources are essential for the MICP process. This study investigated the potential of MICP technology for Cr(VI) remediation under the influence of three calcium sources (CaCl2, Ca(CH3COO)2, Ca(C6H11O7)2). The results indicated that CaCl2 was the most efficient in the mineralization of Cr(VI), and Ca(C6H11O7)2 could significantly promote Cr(VI) reduction. The addition of different calcium sources all promoted the urease activity of Sporosarcina saromensis W5, in which the CaCl2 group showed higher urease activity at the same Ca2+ concentration. Besides, with CaCl2, Ca(CH3COO)2 and Ca(C6H11O7)2 treatments, the final fraction of Cr species (Cr(VI), reduced Cr(III) and organic Cr(III)-complexes) were mainly converted to the carbonate-bound, cytoplasm and cell membrane state, respectively. Furthermore, the characterization results revealed that three calcium sources could co-precipitate with Cr species to produce Ca10Cr6O24(CO3), and calcite and vaterite were present in the CaCl2 and Ca(CH3COO)2 groups, while only calcite was present in the Ca(C6H11O7)2 group. Overall, this study contributes to the optimization of MICP-mediated remediation of heavy metal contaminated soil. CaCl2 was the more suitable calcium source than the other two for the application of MICP technology in the Cr(VI) reduction and mineralization.
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Calcio , Carbonatos , Cromo , Sporosarcina , Cromo/metabolismo , Cromo/química , Calcio/metabolismo , Sporosarcina/metabolismo , Carbonatos/química , Carbonatos/metabolismo , Precipitación Química , Ureasa/metabolismo , Biodegradación Ambiental , Cloruro de Calcio/química , Contaminantes del Suelo/metabolismoRESUMEN
We present the development and validation of an impedance-based urine osmometer for accurate and portable measurement of urine osmolality. The urine osmolality of a urine sample can be estimated by determining the concentrations of the conductive solutes and urea, which make up approximately 94% of the urine composition. Our method utilizes impedance measurements to determine the conductive solutes and urea after hydrolysis with urease enzyme. We built an impedance model using sodium chloride (NaCl) and urea at various known concentrations. In this work, we validated the accuracy of the impedance-based urine osmometer by developing a proof-of-concept first prototype and an integrated urine dipstick second prototype, where both prototypes exhibit an average accuracy of 95.5 ± 2.4% and 89.9 ± 9.1%, respectively in comparison to a clinical freezing point osmometer in the hospital laboratory. While the integrated dipstick design exhibited a slightly lower accuracy than the first prototype, it eliminated the need for pre-mixing or manual pipetting. Impedance calibration curves for conductive and non-conductive solutes consistently yielded results for NaCl but underscored challenges in achieving uniform urease enzyme coating on the dipstick. We also investigated the impact of storing urine at room temperature for 24 hours, demonstrating negligible differences in osmolality values. Overall, our impedance-based urine osmometer presents a promising tool for point-of-care urine osmolality measurements, addressing the demand for a portable, accurate, and user-friendly device with potential applications in clinical and home settings.
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Impedancia Eléctrica , Urea , Ureasa , Urea/orina , Urea/química , Concentración Osmolar , Hidrólisis , Humanos , Ureasa/metabolismo , Ureasa/química , Urinálisis/instrumentación , Diseño de EquipoRESUMEN
Mercury (Hg) is a persistent soil pollutant, and its toxicity can be evaluated using soil enzyme indicators. However, a thorough understanding of how the enzyme resists and remains resilient to Hg stress is essential, as it significantly impacts the accuracy of toxicity assessments. Therefore, it is worthwhile to understand the functional stability of urease in soil under Hg pollution. This study compares the effects of Hg at different concentrations and exposure times on soil urease. Results indicate that soil urease activity was enhanced in the first two hours under low levels of Hg pollution, decreased after six hours of acute Hg pollution, and reached its maximum reduction in 24 hours. The urease in fluvo-aquic soil, with higher soil organic matter showed higher resistance to Hg acute pollution than that in red soil. Over a longer aging process, soil urease activity gradually recovered with time. Hormesis effects were observed in red soil under high Hg stress after 30 days, showing the strong resilience of urease enzyme function to Hg pollution. The ecological dose, ED10, (the Hg concentration causing a 10% reduction in soil urease activity) ranged from 0.09 to 0.59 mg kg-1 under short-term exposure, and was lower than that under a longer aging process (0.28 to 2.71 mg kg-1). Further, aging reduced the Hg ecotoxicity due to decreased Hg availability and the resilience of soil urease activity. This indicates that the risk of Hg pollution estimated by soil urease as an indicator depends on exposure time and enzyme stability. These factors need consideration in heavy metal pollution assessments using soil enzymes.
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Ecotoxicología , Mercurio , Contaminantes del Suelo , Suelo , Ureasa , Ureasa/metabolismo , Mercurio/toxicidad , Contaminantes del Suelo/toxicidad , Suelo/química , Monitoreo del AmbienteRESUMEN
Urinary tract infection caused by Klebsiella, Proteus and Streptococcus is a urease dependent process, hence treatment of these infections by antibacterial compounds lies in inhibition of their virulence factors. The crude methanolic extracts derived from sumac fruit, pomegranate peel and Indian almond leaves were separated into anthocyanin and non-anthocyanin fractions using solid phase cartridges. The inhibitory effect of these fractions was determined on the growth of urease producing species and jack bean urease activity. Known compounds in the fractions were also docked with ureases of different biological origins viz. K. pneumoniae (PDB ID: 8HCN), K. aerogenes (PDB ID: 2KAU), Helicobacter pylori (PDB ID:8HC1)and Canavalia ensiformis (jack bean) (PDB ID: 3LA4) to determine their binding affinities and interaction with the enzyme. All the fractions showed significant inhibition growth for P. mirabilis, S. epidermidis and K.pneumoniae. Among the samples, sumac showed greatest inhibition against all (MIC 6-25 mg.mL-1) while among the fractions, anthocyanin was found to be most active (MIC 6-12 mg/mL). Likewise, all fractions inhibited urease with lowest ICs50 shown by sumac fractions (21-116 µg.mL-1). Out of 39 compounds docked, 27 showed interaction with movable flaps and/or active site of ureases which explains their mode of inhibition.
Asunto(s)
Polifenoles , Granada (Fruta) , Prunus dulcis , Ureasa , Ureasa/antagonistas & inhibidores , Ureasa/metabolismo , Polifenoles/farmacología , Polifenoles/química , Granada (Fruta)/química , Prunus dulcis/química , Canavalia/enzimología , Extractos Vegetales/farmacología , Extractos Vegetales/química , Antibacterianos/farmacología , Antibacterianos/química , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química , Pruebas de Sensibilidad Microbiana , Simulación del Acoplamiento Molecular , Bacterias/efectos de los fármacos , Bacterias/enzimologíaRESUMEN
As part of the multifaceted strategies developed to shape the common environmental policy, considerable attention is now being paid to assessing the degree of environmental degradation in soil under xenobiotic pressure. Bisphenol A (BPA) has only been marginally investigated in this ecosystem context. Therefore, research was carried out to determine the biochemical properties of soils contaminated with BPA at two levels of contamination: 500 mg and 1000 mg BPA kg-1 d.m. of soil. Reliable biochemical indicators of soil changes, whose activity was determined in the pot experiment conducted, were used: dehydrogenases, catalase, urease, acid phosphatase, alkaline phosphatase, arylsulfatase, and ß-glucosidase. Using the definition of soil health as the ability to promote plant growth, the influence of BPA on the growth and development of Zea mays, a plant used for energy production, was also tested. As well as the biomass of aerial parts and roots, the leaf greenness index (SPAD) of Zea mays was also assessed. A key aspect of the research was to identify those of the six remediating substances-molecular sieve, zeolite, sepiolite, starch, grass compost, and fermented bark-whose use could become common practice in both environmental protection and agriculture. Exposure to BPA revealed the highest sensitivity of dehydrogenases, urease, and acid phosphatase and the lowest sensitivity of alkaline phosphatase and catalase to this phenolic compound. The enzyme response generated a reduction in the biochemical fertility index (BA21) of 64% (500 mg BPA) and 70% (1000 mg BPA kg-1 d.m. of soil). The toxicity of BPA led to a drastic reduction in root biomass and consequently in the aerial parts of Zea mays. Compost and molecular sieve proved to be the most effective in mitigating the negative effect of the xenobiotic on the parameters discussed. The results obtained are the first research step in the search for further substances with bioremediation potential against both soil and plants under BPA pressure.
Asunto(s)
Fosfatasa Ácida , Compuestos de Bencidrilo , Fenoles , Contaminantes del Suelo , Suelo , Zea mays , Fenoles/química , Compuestos de Bencidrilo/química , Contaminantes del Suelo/química , Zea mays/química , Suelo/química , Fosfatasa Ácida/metabolismo , Arilsulfatasas/metabolismo , Fosfatasa Alcalina/metabolismo , Zeolitas/química , Oxidorreductasas/metabolismo , Ureasa/metabolismo , Catalasa/metabolismo , Biodegradación Ambiental , Silicatos de Magnesio/química , Almidón/química , beta-Glucosidasa/metabolismo , Compostaje/métodosRESUMEN
The synergistic remediation of heavy metal-contaminated soil by functional strains and biochar has been widely studied. However, the mechanisms by which urease-producing bacteria combine with pig manure biochar (PMB) to immobilize Cd and inhibit Cd absorption in vegetables are still unclear. In our study, the effects and mechanisms of PMB combined with the urease-producing bacterium TJ6 (TJ6 + PMB) on Cd adsorption were explored. The effects of TJ6 + PMB on the Cd content and pH of the leachate were also studied through a 56-day soil leaching experiment. Moreover, the effects of the complexes on Cd absorption and microbial mechanisms in lettuce were explored through pot experiments. The results showed that PMB provided strain TJ6 with a greater ability to adsorb Cd, inducing the generation of CdS and CdCO3, and thereby reducing the Cd content (71.1%) and increasing the pH and urease activity in the culture medium. TJ6 + PMB improved lettuce dry weight and reduced Cd absorption. These positive effects were likely due to (1) TJ6 + PMB increased the organic matter and NH4+ contents, (2) TJ6 + PMB transformed available Cd into residual Cd and decreased the Cd content in the leachate, and (3) TJ6 + PMB altered the structure of the rhizosphere bacterial and fungal communities in lettuce, increasing the relative abundances of Stachybotrys, Agrocybe, Gaiellales, and Gemmatimonas. These genera can promote plant growth, decompose organic matter, and release phosphorus. Interestingly, the fungal communities were more sensitive to the addition of TJ6 and PMB, which play important roles in the decomposition of organic matter and immobilization of Cd. In conclusion, this study revealed the mechanism by which urease-producing bacteria combined with pig manure biochar immobilize Cd and provided a theoretical basis for safe pig manure return to Cd-polluted farmland. This study also provides technical approaches and bacterial resources for the remediation of heavy metal-contaminated soil.
Asunto(s)
Cadmio , Carbón Orgánico , Lactuca , Estiércol , Contaminantes del Suelo , Ureasa , Cadmio/metabolismo , Carbón Orgánico/química , Animales , Ureasa/metabolismo , Porcinos , Contaminantes del Suelo/metabolismo , Bacterias/metabolismo , Suelo/químicaRESUMEN
Sodium ions and protons regulate various fundamental processes at the cell and tissue levels across all biological kingdoms. It is therefore pivotal for bioelectronic devices, such as biosensors and biotransducers, to control the transport of these ions through biological membranes. Our study explores the regulation of proton and sodium concentrations by integrating an Na+-type ATP synthase, a glucose dehydrogenase (GDH), and a urease into a multienzyme logic system. This system is designed to operate using various chemical control input signals, while the output current corresponds to the local change in proton or sodium concentrations. Therein, a H+ and Na+ biotransducer was integrated to fulfill the roles of signal transducers for the monitoring and simultaneous control of Na+ and H+ levels, respectively. To increase the proton concentration at the output, we utilized GDH driven by the inputs of glucose and nicotinamide adenine dinucleotide (NAD+), while recorded the signal change from the biotransducer, together acting as an AND enzyme logic gate. On the contrary, we introduced urease enzyme which hydrolyzed urea to control the decrease in proton concentration, serving as a NOT gate and reset. By integrating these two enzyme logic gates we formed a simple multienzyme logic system for the control of proton concentrations. Furthermore, we also demonstrate a more complex, Na+-type ATP synthase-urease multienzyme logic system, controlled by the two different inputs of ADP and urea. By monitoring the voltage of the peak current as the output signal, this logic system acts as an AND enzyme logic gate. This study explores how multienzyme logic systems can modulate biologically important ion concentrations, opening the door toward advanced biological on-demand control of a variety of bioelectronic enzyme-based devices, such as biosensors and biotransducers.