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1.
MAbs ; 16(1): 2375798, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38984665

RESUMEN

Monoclonal antibodies (mAb) and other biological drugs are affected by enzymatic polysorbate (PS) degradation that reduces product stability and jeopardizes the supply of innovative medicines. PS represents a critical surfactant stabilizing the active pharmaceutical ingredients, which are produced by recombinant Chinese hamster ovary (CHO) cell lines. While the list of potential PS-degrading CHO host cell proteins (HCPs) has grown over the years, tangible data on industrially relevant HCPs are still scarce. By means of a highly sensitive liquid chromatography-tandem mass spectrometry method, we investigated seven different mAb products, resulting in the identification of 12 potentially PS-degrading hydrolases, including the strongly PS-degrading lipoprotein lipase (LPL). Using an LPL knockout CHO host cell line, we were able to stably overexpress and purify the remaining candidate hydrolases through orthogonal affinity chromatography methods, enabling their detailed functional characterization. Applying a PS degradation assay, we found nine mostly secreted, PS-active hydrolases with varying hydrolytic activity. All active hydrolases showed a serine-histidine-aspartate/glutamate catalytical triad. Further, we subjected the active hydrolases to pH-screenings and revealed a diverse range of activity optima, which can facilitate the identification of residual hydrolases during bioprocess development. Ultimately, we compiled our dataset in a risk matrix identifying PAF-AH, LIPA, PPT1, and LPLA2 as highly critical hydrolases based on their cellular expression, detection in purified antibodies, active secretion, and PS degradation activity. With this work, we pave the way toward a comprehensive functional characterization of PS-degrading hydrolases and provide a basis for a future reduction of PS degradation in biopharmaceutical drug products.


Asunto(s)
Anticuerpos Monoclonales , Cricetulus , Hidrolasas , Células CHO , Animales , Anticuerpos Monoclonales/química , Hidrolasas/metabolismo , Polisorbatos/química , Productos Biológicos/metabolismo , Humanos
2.
Anal Biochem ; 693: 115598, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38964700

RESUMEN

The widespread use of polyamides such as nylons has led to the accumulation of nylon waste, which is particularly resistant to decomposition due to the intrinsic stability of the amide bond. New methods are required for the true recycling of these waste materials by depolymerization. Enzymes that are capable of hydrolyzing polyamides have been proposed as biocatalysts that may be suitable for this application. NylC is an enzyme that can mediate the hydrolysis of aminohexanoic acid oligomers, and to some extent, bulk polymers. However, current assays to characterize the activity of this enzyme require long reaction times and/or rely on secondary reactions to quantify hydrolysis. Herein, we have designed structurally-optimized small molecule chromogenic esters that serve as substrate analogues for monitoring NylC acyltransferase activity in a continuous manner. This assay can be performed in minutes at room temperature, and the substrate N-acetyl-GABA-pNP ester (kcat = 0.37 s-1, KM = 256 µM) shows selectivity for NylC in complex biological media. We also demonstrate that activity towards this substrate analogue correlates with amide hydrolysis, which is the primary activity of this enzyme. Furthermore, our screening of substrate analogues provides insight into the substrate specificity of NylC, which is relevant to biocatalytic applications.


Asunto(s)
Nylons , Nylons/química , Nylons/metabolismo , Hidrólisis , Especificidad por Sustrato , Hidrolasas/metabolismo , Hidrolasas/química , Aciltransferasas/metabolismo , Aciltransferasas/química , Aciltransferasas/análisis , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/química
3.
Appl Microbiol Biotechnol ; 108(1): 404, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38953996

RESUMEN

Polyethylene terephthalate (PET) is a major component of plastic waste. Enzymatic PET hydrolysis is the most ecofriendly recycling technology. The biorecycling of PET waste requires the complete depolymerization of PET to terephthalate and ethylene glycol. The history of enzymatic PET depolymerization has revealed two critical issues for the industrial depolymerization of PET: industrially available PET hydrolases and pretreatment of PET waste to make it susceptible to full enzymatic hydrolysis. As none of the wild-type enzymes can satisfy the requirements for industrialization, various mutational improvements have been performed, through classical technology to state-of-the-art computational/machine-learning technology. Recent engineering studies on PET hydrolases have brought a new insight that flexibility of the substrate-binding groove may improve the efficiency of PET hydrolysis while maintaining sufficient thermostability, although the previous studies focused only on enzymatic thermostability above the glass transition temperature of PET. Industrial biorecycling of PET waste is scheduled to be implemented, using micronized amorphous PET. Next stage must be the development of PET hydrolases that can efficiently degrade crystalline parts of PET and expansion of target PET materials, not only bottles but also textiles, packages, and microplastics. This review discusses the current status of PET hydrolases, their potential applications, and their profespectal goals. KEY POINTS: • PET hydrolases must be thermophilic, but their operation must be below 70 °C • Classical and state-of-the-art engineering approaches are useful for PET hydrolases • Enzyme activity on crystalline PET is most expected for future PET biorecycling.


Asunto(s)
Hidrolasas , Tereftalatos Polietilenos , Tereftalatos Polietilenos/metabolismo , Tereftalatos Polietilenos/química , Hidrolasas/metabolismo , Hidrolasas/química , Hidrolasas/genética , Hidrólisis , Ingeniería de Proteínas/métodos , Biodegradación Ambiental , Reciclaje
4.
J Hazard Mater ; 474: 134838, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-38850944

RESUMEN

Microplastics (MPs) pose an emerging threat to soil ecological function, yet effective solutions remain limited. This study introduces a novel approach using magnetic biochar immobilized PET hydrolase (MB-LCC-FDS) to degrade soil polyethylene terephthalate microplastics (PET-MPs). MB-LCC-FDS exhibited a 1.68-fold increase in relative activity in aquatic solutions and maintained 58.5 % residual activity after five consecutive cycles. Soil microcosm experiment amended with MB-LCC-FDS observed a 29.6 % weight loss of PET-MPs, converting PET into mono(2-hydroxyethyl) terephthalate (MHET). The generated MHET can subsequently be metabolized by soil microbiota to release terephthalic acid. The introduction of MB-LCC-FDS shifted the functional composition of soil microbiota, increasing the relative abundances of Microbacteriaceae and Skermanella while reducing Arthobacter and Vicinamibacteraceae. Metagenomic analysis revealed that MB-LCC-FDS enhanced nitrogen fixation, P-uptake and transport, and organic-P mineralization in PET-MPs contaminated soil, while weakening the denitrification and nitrification. Structural equation model indicated that changes in soil total carbon and Simpson index, induced by MB-LCC-FDS, were the driving factors for soil carbon and nitrogen transformation. Overall, this study highlights the synergistic role of magnetic biochar-immobilized PET hydrolase and soil microbiota in degrading soil PET-MPs, and enhances our understanding of the microbiome and functional gene responses to PET-MPs and MB-LCC-FDS in soil systems.


Asunto(s)
Carbón Orgánico , Hidrolasas , Fósforo , Tereftalatos Polietilenos , Microbiología del Suelo , Contaminantes del Suelo , Hidrolasas/metabolismo , Tereftalatos Polietilenos/química , Tereftalatos Polietilenos/metabolismo , Contaminantes del Suelo/metabolismo , Carbón Orgánico/química , Fósforo/metabolismo , Fósforo/química , Microplásticos/toxicidad , Biodegradación Ambiental , Enzimas Inmovilizadas/metabolismo , Enzimas Inmovilizadas/química , Nitrógeno/metabolismo , Ciclo del Nitrógeno , Microbiota/efectos de los fármacos , Bacterias/genética , Bacterias/metabolismo , Bacterias/efectos de los fármacos
5.
J Assoc Physicians India ; 72(5): 97-100, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38881119

RESUMEN

Chorea is a very commonly encountered movement disorder; it has various etiologies, and it can have autoimmune, vascular, degenerative, or paraneoplastic etiology. Our patient had acute onset chorea and a strong history of smoking, which made us suspect first vascular followed by paraneoplastic cause. After ruling out common vascular and metabolic causes, his whole body positron emission tomography (PET) scan revealed a mass in the right upper lobe, a biopsy revealed a small cell carcinoma lung and a paraneoplastic panel showed antibodies positive for collapsin response mediator protein 5 antigen (CRMP-5/CV2); the patient was started on immunomodulation, chemotherapy with the variable response, he succumbed to a cardiac event after treatment.


Asunto(s)
Corea , Neoplasias Pulmonares , Humanos , Corea/etiología , Corea/diagnóstico , Masculino , Neoplasias Pulmonares/complicaciones , Neoplasias Pulmonares/diagnóstico , Proteínas del Tejido Nervioso/inmunología , Carcinoma Pulmonar de Células Pequeñas/complicaciones , Resultado Fatal , Persona de Mediana Edad , Tomografía de Emisión de Positrones , Hidrolasas , Proteínas Asociadas a Microtúbulos
6.
Front Cell Infect Microbiol ; 14: 1392249, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38915922

RESUMEN

In recent years, there has been increasing interest in studying gut microbiome-derived hydrolases in relation to oral drug metabolism, particularly focusing on natural product drugs. Despite the significance of natural product drugs in the field of oral medications, there is a lack of research on the regulatory interplay between gut microbiome-derived hydrolases and these drugs. This review delves into the interaction between intestinal microbiome-derived hydrolases and natural product drugs metabolism from three key perspectives. Firstly, it examines the impact of glycoside hydrolases, amide hydrolases, carboxylesterase, bile salt hydrolases, and epoxide hydrolase on the structure of natural products. Secondly, it explores how natural product drugs influence microbiome-derived hydrolases. Lastly, it analyzes the impact of interactions between hydrolases and natural products on disease development and the challenges in developing microbial-derived enzymes. The overarching goal of this review is to lay a solid theoretical foundation for the advancement of research and development in new natural product drugs and personalized treatment.


Asunto(s)
Productos Biológicos , Microbioma Gastrointestinal , Hidrolasas , Productos Biológicos/metabolismo , Productos Biológicos/farmacología , Humanos , Hidrolasas/metabolismo , Animales , Glicósido Hidrolasas/metabolismo , Bacterias/metabolismo , Bacterias/enzimología
7.
ACS Appl Mater Interfaces ; 16(27): 35566-35575, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38922631

RESUMEN

Encapsulating enzymes within metal-organic frameworks such as zeolitic imidazolate framework-8 (ZIF-8) has been demonstrated to enhance enzymatic performance under harsh conditions. However, by computer-aided analysis, we revealed that highly hydrophobic organic ligands and unfavorable metal ions could greatly impair the activity of haloalkane dehalogenase DhaA by directly interacting with the catalytic sites, causing an extremely low activity of DhaA after encapsulating within ZIF-8. We also found that the presence of a protecting polymer could protect DhaA from the damage of organic ligands and metal ions and that a positively charged amino acid could increase the DhaA activity. Based on the simulations and experimental observations, we have designed to coencapsulate DhaA with poly(vinylpyrrolidone) (PVP) and lysine (Lys) within the amorphous Co-based metal azolate coordination polymer (CoCP). The as-prepared immobilized enzyme (DhaA/PVP/Lys@CoCP) exhibited significantly increased activity (91.5 times higher than that of DhaA@ZIF-8), dramatically enhanced thermostability at 50-70 °C, greatly improved catalytic performance in several organic solvent solutions, and good recyclability (over 75% of the initial activity after 10 cycles). The superiority of the immobilized enzyme was also demonstrated with a substrate frequently detected in the real world. In addition to the protective effect of PVP and positive effect of Lys, experimental and computational investigations unveiled other two favorable aspects that contributed to the enhanced enzymatic performance: (1) high hydrophilicity of the immobilization material and (2) the use of Co2+ with a minimal negative effect on DhaA. The research has thus provided a promising immobilized DhaA with favorable catalytic performance and great potential in industrial applications.


Asunto(s)
Enzimas Inmovilizadas , Hidrolasas , Interacciones Hidrofóbicas e Hidrofílicas , Estructuras Metalorgánicas , Hidrolasas/química , Hidrolasas/metabolismo , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Estructuras Metalorgánicas/química , Polímeros/química
8.
Commun Biol ; 7(1): 781, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38944651

RESUMEN

Macrolide antibiotics, pivotal in clinical therapeutics, are confronting resistance challenges mediated by enzymes like macrolide esterases, which are classified into Ere-type and the less studied Est-type. In this study, we provide the biochemical confirmation of EstX, an Est-type macrolide esterase that initially identified as unknown protein in the 1980s. EstX is capable of hydrolyzing four 16-membered ring macrolides, encompassing both veterinary (tylosin, tidipirosin, and tilmicosin) and human-use (leucomycin A5) antibiotics. It uses typical catalytic triad (Asp233-His261-Ser102) from alpha/beta hydrolase superfamily for ester bond hydrolysis. Further genomic context analysis suggests that the dissemination of estX is likely facilitated by mobile genetic elements such as integrons and transposons. The global distribution study indicates that bacteria harboring the estX gene, predominantly pathogenic species like Escherichia coli, Salmonella enterica, and Klebsiella pneumoniae, are prevalent in 74 countries across 6 continents. Additionally, the emergence timeline of the estX gene suggests its proliferation may be linked to the overuse of macrolide antibiotics. The widespread prevalence and dissemination of Est-type macrolide esterase highlight an urgent need for enhanced monitoring and in-depth research, underlining its significance as an escalating public health issue.


Asunto(s)
Esterasas , Esterasas/genética , Esterasas/metabolismo , Esterasas/química , Antibacterianos/farmacología , Antibacterianos/metabolismo , Macrólidos/metabolismo , Humanos , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/química , Filogenia , Hidrolasas/genética , Hidrolasas/metabolismo , Hidrolasas/química
9.
Arch Biochem Biophys ; 758: 110048, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38848996

RESUMEN

The inherent structural properties of enzymes are critical in defining catalytic function. Often, studies to evaluate the relationship between structure and function are limited to only one defined structural element. The two-component flavin-dependent desulfonase family of enzymes involved in bacterial sulfur acquisition utilize a comprehensive range of structural features to carry out the desulfonation of organosulfur compounds. These metabolically essential two-component FMN-dependent desulfonase systems have been proposed to utilize oligomeric changes, protein-protein interactions for flavin transfer, and common mechanistic steps for carbon-sulfur bond cleavage. This review is focused on our current functional and structural understanding of two-component FMN-dependent desulfonase systems from multiple bacterial sources. Mechanistic and structural comparisons from recent independent studies provide fresh insights into the overall functional properties of these systems and note areas in need of further investigation. The review acknowledges current studies focused on evaluating the structural properties of these enzymes in relationship to their distinct catalytic function. The role of these enzymes in maintaining adequate sulfur levels, coupled with the conserved nature of these enzymes in diverse bacteria, underscore the importance in understanding the functional and structural nuances of these systems.


Asunto(s)
Proteínas Bacterianas , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Bacterias/enzimología , Compuestos de Azufre/metabolismo , Compuestos de Azufre/química , Hidrolasas/química , Hidrolasas/metabolismo , Mononucleótido de Flavina/metabolismo , Mononucleótido de Flavina/química , Azufre/metabolismo , Azufre/química , Flavinas/metabolismo , Flavinas/química , Relación Estructura-Actividad , Carbono/metabolismo , Carbono/química
10.
Mol Biol Cell ; 35(8): mr6, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38888935

RESUMEN

Maintenance of a pool of active lysosomes with acidic pH and degradative hydrolases is crucial for cell health. Abnormalities in lysosomal function are closely linked to diseases, such as lysosomal storage disorders, neurodegeneration, intracellular infections, and cancer among others. Emerging body of research suggests the malfunction of lysosomal hydrolase trafficking pathway to be a common denominator of several disease pathologies. However, available conventional tools to assess lysosomal hydrolase trafficking are insufficient and fail to provide a comprehensive picture about the trafficking flux and location of lysosomal hydrolases. To address some of the shortcomings, we designed a genetically-encoded fluorescent reporter containing a lysosomal hydrolase tandemly tagged with pH sensitive and insensitive fluorescent proteins, which can spatiotemporally trace the trafficking of lysosomal hydrolases. As a proof of principle, we demonstrate that the reporter can detect perturbations in hydrolase trafficking, that are induced by pharmacological manipulations and pathophysiological conditions like intracellular protein aggregates. This reporter can effectively serve as a probe for mapping the mechanistic intricacies of hydrolase trafficking pathway in health and disease and is a utilitarian tool to identify genetic and pharmacological modulators of this pathway, with potential therapeutic implications.


Asunto(s)
Hidrolasas , Lisosomas , Manosafosfatos , Transporte de Proteínas , Humanos , Lisosomas/metabolismo , Manosafosfatos/metabolismo , Hidrolasas/metabolismo , Hidrolasas/genética , Fluorescencia , Genes Reporteros , Proteínas Luminiscentes/metabolismo , Proteínas Luminiscentes/genética , Proteínas Fluorescentes Verdes/metabolismo , Concentración de Iones de Hidrógeno , Células HeLa
11.
Int J Mol Sci ; 25(11)2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38891866

RESUMEN

Vibrio fluvialis is an emerging foodborne pathogenic bacterium that can cause severe cholera-like diarrhea and various extraintestinal infections, posing challenges to public health and food safety worldwide. The arginine deiminase (ADI) pathway plays an important role in bacterial environmental adaptation and pathogenicity. However, the biological functions and regulatory mechanisms of the pathway in V. fluvialis remain unclear. In this study, we demonstrate that L-arginine upregulates the expression of the ADI gene cluster and promotes the growth of V. fluvialis. The ADI gene cluster, which we proved to be comprised of two operons, arcD and arcACB, significantly enhances the survival of V. fluvialis in acidic environments both in vitro (in culture medium and in macrophage) and in vivo (in mice). The mRNA level and reporter gene fusion analyses revealed that ArgR, a transcriptional factor, is necessary for the activation of both arcD and arcACB transcriptions. Bioinformatic analysis predicted the existence of multiple potential ArgR binding sites at the arcD and arcACB promoter regions that were further confirmed by electrophoretic mobility shift assay, DNase I footprinting, or point mutation analyses. Together, our study provides insights into the important role of the ArgR-ADI pathway in the survival of V. fluvialis under acidic conditions and the detailed molecular mechanism. These findings will deepen our understanding of how environmental changes and gene expression interact to facilitate bacterial adaptations and virulence.


Asunto(s)
Proteínas Bacterianas , Regulación Bacteriana de la Expresión Génica , Hidrolasas , Animales , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Ratones , Hidrolasas/metabolismo , Hidrolasas/genética , Regiones Promotoras Genéticas , Operón/genética , Proteínas Represoras/metabolismo , Proteínas Represoras/genética , Vibrio/genética , Vibrio/metabolismo , Vibrio/patogenicidad , Arginina/metabolismo , Familia de Multigenes , Virulencia/genética , Viabilidad Microbiana
12.
Biochemistry ; 63(13): 1663-1673, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38885634

RESUMEN

The mono(2-hydroxyethyl) terephthalate hydrolase (MHETase) from Ideonella sakaiensis carries out the second step in the enzymatic depolymerization of poly(ethylene terephthalate) (PET) plastic into the monomers terephthalic acid (TPA) and ethylene glycol (EG). Despite its potential industrial and environmental applications, poor recombinant expression of MHETase has been an obstacle to its industrial application. To overcome this barrier, we developed an assay allowing for the medium-throughput quantification of MHETase activity in cell lysates and whole-cell suspensions, which allowed us to screen a library of engineered variants. Using consensus design, we generated several improved variants that exhibit over 10-fold greater whole-cell activity than wild-type (WT) MHETase. This is revealed to be largely due to increased soluble expression, which biochemical and structural analysis indicates is due to improved protein folding.


Asunto(s)
Burkholderiales , Burkholderiales/enzimología , Burkholderiales/genética , Burkholderiales/metabolismo , Ácidos Ftálicos/metabolismo , Ácidos Ftálicos/química , Hidrolasas/metabolismo , Hidrolasas/genética , Hidrolasas/química , Solubilidad , Tereftalatos Polietilenos/metabolismo , Tereftalatos Polietilenos/química , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/química , Ingeniería de Proteínas/métodos , Pliegue de Proteína , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/química , Modelos Moleculares
13.
Sci Rep ; 14(1): 14449, 2024 06 24.
Artículo en Inglés | MEDLINE | ID: mdl-38914665

RESUMEN

As genomic databases expand and artificial intelligence tools advance, there is a growing demand for efficient characterization of large numbers of proteins. To this end, here we describe a generalizable pipeline for high-throughput protein purification using small-scale expression in E. coli and an affordable liquid-handling robot. This low-cost platform enables the purification of 96 proteins in parallel with minimal waste and is scalable for processing hundreds of proteins weekly per user. We demonstrate the performance of this method with the expression and purification of the leading poly(ethylene terephthalate) hydrolases reported in the literature. Replicate experiments demonstrated reproducibility and enzyme purity and yields (up to 400 µg) sufficient for comprehensive analyses of both thermostability and activity, generating a standardized benchmark dataset for comparing these plastic-degrading enzymes. The cost-effectiveness and ease of implementation of this platform render it broadly applicable to diverse protein characterization challenges in the biological sciences.


Asunto(s)
Escherichia coli , Robótica , Robótica/métodos , Escherichia coli/genética , Ingeniería de Proteínas/métodos , Ensayos Analíticos de Alto Rendimiento/métodos , Ensayos Analíticos de Alto Rendimiento/economía , Hidrolasas/metabolismo , Hidrolasas/química , Hidrolasas/genética , Tereftalatos Polietilenos/química , Reproducibilidad de los Resultados
14.
J Hazard Mater ; 473: 134716, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38797074

RESUMEN

Ochratoxin A (OTA) is a toxic secondary metabolite that widely contaminates agro-products and poses a significant dietary risk to human health. Previously, a carboxypeptidase CP4 was characterized for OTA degradation in Lysobacter sp. CW239, but the degradation activity was much lower than its host strain CW239. In this study, an amidohydrolase ADH2 was screened for OTA hydrolysis in this strain. The result showed that 50 µg/L OTA was completely degraded by 1.0 µg/mL rADH2 within 5 min, indicating ultra-efficient activity. Meanwhile, the two hydrolases (i.e., CP4 and ADH2) in the strain CW239 showed the same degradation manner, which transformed the OTA to ochratoxin α (OTα) and l-ß-phenylalanine. Gene mutants (Δcp4, Δadh2 and Δcp4-adh2) testing result showed that OTA was co-degraded by carboxypeptidase CP4 and amidohydrolase ADH2, and the two hydrolases are sole agents in strain CW239 for OTA degradation. Hereinto, the ADH2 was the overwhelming efficient hydrolase, and the two types of hydrolases co-degraded OTA in CW239 by synergistic effect. The results of this study are highly significant to ochratoxin A contamination control during agro-products production and postharvest.


Asunto(s)
Lysobacter , Ocratoxinas , Ocratoxinas/metabolismo , Ocratoxinas/toxicidad , Lysobacter/metabolismo , Lysobacter/genética , Amidohidrolasas/metabolismo , Amidohidrolasas/genética , Carboxipeptidasas/metabolismo , Carboxipeptidasas/genética , Hidrolasas/metabolismo , Hidrolasas/genética
15.
J Phys Chem B ; 128(23): 5567-5575, 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38814729

RESUMEN

Methyl-parathion hydrolase (MPH), which evolved from dihydrocoumarin hydrolase, offers one of the most efficient enzymes for the hydrolysis of methyl-parathion. Interestingly, the substrate preference of MPH shifts from the methyl-parathion to the lactone dihydrocoumarin (DHC) after its mutation of five specific residues (R72L, L273F, L258H, T271I, and S193Δ, m5-MPH). Here, extensive QM/MM calculations and MM MD simulations have been used to delve into the structure-function relationship of MPH enzymes and plausible mechanisms for the chemical and nonchemical steps, including the transportation and binding of the substrate DHC to the active site, the hydrolysis reaction, and the product release. The results reveal that the five mutations remodel the active pocket and reposition DHC within the active site, leading to stronger enzyme-substrate interactions. The MM/GBSA-estimated binding free energies are about -20.7 kcal/mol for m5-MPH and -17.1 kcal/mol for wild-type MPH. Furthermore, this conformational adjustment of the protein may facilitate the chemical step of DHC hydrolysis and the product release, although there is a certain influence on the substrate transport. The hydrolytic reaction begins with the nucleophilic attack of the bridging OH- with the energy barriers of 22.0 and 18.0 kcal/mol for the wild-type and m5-MPH enzymes, respectively, which is rate-determining for the entire process. Unraveling these mechanistic intricacies may help in the understanding of the natural evolution of enzymes for diverse substrates and establish the enzyme structure-function relationship.


Asunto(s)
Cumarinas , Simulación de Dinámica Molecular , Teoría Cuántica , Cumarinas/química , Cumarinas/metabolismo , Hidrólisis , Dominio Catalítico , Especificidad por Sustrato , Termodinámica , Hidrolasas/metabolismo , Hidrolasas/química , Hidrolasas/genética
16.
J Chem Inf Model ; 64(11): 4530-4541, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38808649

RESUMEN

By performing molecular dynamics (MD), quantum mechanical/molecular mechanical (QM/MM) calculations, and QM cluster calculations, the origin of chemoselectivity of halohydrin dehalogenase (HHDH)-catalyzed ring-opening reactions of epoxide with the nucleophilic reagent NO2- has been explored. Four possible chemoselective pathways were considered, and the computed results indicate that the pathway associated with the nucleophilic attack on the Cα position of epoxide by NO2- is most energetically favorable and has an energy barrier of 12.9 kcal/mol, which is close to 14.1 kcal/mol derived from experimental kinetic data. A hydrogen bonding network formed by residues Ser140, Tyr153, and Arg157 can strengthen the electrophilicity of the active site of the epoxide substrate to affect chemoselectivity. To predict the energy barrier trends of the chemoselective transition states, multiple analyses including distortion analysis and electrophilic Parr function (Pk+) analysis were carried out with or without an enzyme environment. The obtained insights should be valuable for the rational design of enzyme-catalyzed and biomimetic organocatalytic epoxide ring-opening reactions with special chemoselectivity.


Asunto(s)
Biocatálisis , Compuestos Epoxi , Hidrolasas , Hidrolasas/metabolismo , Hidrolasas/química , Compuestos Epoxi/química , Compuestos Epoxi/metabolismo , Simulación de Dinámica Molecular , Teoría Cuántica , Dominio Catalítico , Especificidad por Sustrato
17.
J Histochem Cytochem ; 72(6): 387-397, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38752478

RESUMEN

During investigating the role of peptidylarginine deiminase (PAD) enzymes in dilated cardiomyopathy (DCM), we observed unique spheroid formation in DCM-myofibroblasts that distinguished them from normal cardiac myofibroblasts. The present study aimed to assess the presence of PADs, the extracellular matrix (ECM), and citrullination in DCM spheroids using immunofluorescence staining and imaging techniques. The results revealed that spheroids derived from DCM-myofibroblasts displayed a more distinctive, tightly packed structure compared with those derived from human cardiac fibroblasts. DCM spheroids showed abundant protein expression of the PAD 2, 3, and 4 enzymes. Notably, increased Ki67 protein expression was associated with increased proliferation in DCM spheroids. Cytoskeletal proteins such as Col-1A, vimentin, α-SMA, and F-actin were highly abundant in DCM spheroids. Furthermore, DCM spheroids contained citrullinated cytoskeletal proteins, mainly citrullinated vimentin and citrullinated fibronectin. These observations supported the occurrence of PAD-mediated citrullination of ECM proteins in DCM spheroids. Collectively, these findings describe the distinctive features of DCM spheroids, representing the cellular characteristics of DCM myofibroblasts. Therefore, DCM spheroids can serve as an in vitro model for further investigations of disease morphology and therapeutic efficacy.


Asunto(s)
Citrulinación , Proteínas del Citoesqueleto , Miofibroblastos , Desiminasas de la Arginina Proteica , Humanos , Miofibroblastos/metabolismo , Proteínas del Citoesqueleto/metabolismo , Proteínas del Citoesqueleto/análisis , Desiminasas de la Arginina Proteica/metabolismo , Esferoides Celulares/metabolismo , Hidrolasas/metabolismo , Células Cultivadas
18.
J Biol Inorg Chem ; 29(4): 427-439, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38796812

RESUMEN

Chlorothalonil (2,4,5,6-tetrachloroisophthalonitrile; TPN) is an environmentally persistent fungicide that sees heavy use in the USA and is highly toxic to aquatic species and birds, as well as a probable human carcinogen. The chlorothalonil dehalogenase from Pseudomonas sp. CTN-3 (Chd, UniProtKB C9EBR5) degrades TPN to its less toxic 4-OH-TPN analog making it an exciting candidate for the development of a bioremediation process for TPN; however, little is currently known about its catalytic mechanism. Therefore, an active site residue histidine-114 (His114) which forms a hydrogen bond with the Zn(II)-bound water/hydroxide and has been suggested to be the active site acid/base, was substituted by an Ala residue. Surprisingly, ChdH114A exhibited catalytic activity with a kcat value of 1.07 s-1, ~ 5% of wild-type (WT) Chd, and a KM of 32 µM. Thus, His114 is catalytically important but not essential. The electronic and structural aspects of the WT Chd and ChdH114A active sites were examined using UV-Vis and EPR spectroscopy on the catalytically competent Co(II)-substituted enzyme as well as all-atomistic molecular dynamics (MD) simulations. Combination of these data suggest His114 can quickly and reversibly move nearly 2 Å between one conformation that facilitates catalysis and another that enables product egress and active site recharge. In light of experimental and computational data on ChdH114A, Asn216 appears to play a role in substrate binding and preorganization of the transition-state while Asp116 likely facilitates the deprotonation of the Zn(II)-bound water in the absence of His114. Based on these data, an updated proposed catalytic mechanism for Chd is presented.


Asunto(s)
Histidina , Nitrilos , Pseudomonas , Pseudomonas/enzimología , Pseudomonas/metabolismo , Nitrilos/metabolismo , Nitrilos/química , Histidina/química , Histidina/metabolismo , Hidrólisis , Biocatálisis , Dominio Catalítico , Fungicidas Industriales/química , Fungicidas Industriales/metabolismo , Halogenación , Hidrolasas/metabolismo , Hidrolasas/química
19.
Biochemistry ; 63(12): 1578-1587, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38803051

RESUMEN

l-(+)-Tartaric acid plays important roles in various industries, including pharmaceuticals, foods, and chemicals. cis-Epoxysuccinate hydrolases (CESHs) are crucial for converting cis-epoxysuccinate to l-(+)-tartrate in the industrial production process. There is, however, a lack of detailed structural and mechanistic information on CESHs, limiting the discovery and engineering of these industrially relevant enzymes. In this study, we report the crystal structures of RoCESH and KoCESH-l-(+)-tartrate complex. These structures reveal the key amino acids of the active pocket and the catalytic triad residues and elucidate a dynamic catalytic process involving conformational changes of the active site. Leveraging the structural insights, we identified a robust BmCESH (550 ± 20 U·mg-1) with sustained catalytic activity even at a 3 M substrate concentration. After six batches of transformation, immobilized cells with overexpressed BmCESH maintained 69% of their initial activity, affording an overall productivity of 200 g/L/h. These results provide valuable insights into the development of high-efficiency CESHs and the optimization of biotransformation processes for industrial uses.


Asunto(s)
Biocatálisis , Tartratos , Tartratos/metabolismo , Tartratos/química , Dominio Catalítico , Cristalografía por Rayos X , Hidrolasas/química , Hidrolasas/metabolismo , Hidrolasas/genética , Modelos Moleculares , Conformación Proteica
20.
Mol Carcinog ; 63(8): 1559-1571, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38780126

RESUMEN

The therapeutic effect of anlotinib on neuroblastoma is still not fully understood. This study aims to explore the differentiation therapeutic effects of anlotinib on neuroblastoma and its potential association with the neural development regulatory protein collapsin response mediator protein 5 (CRMP5), both in vivo and in vitro. A patient-derived xenograft (PDX) model was established to observe the therapeutic effect of anlotinib. Neuroblastoma cell lines SK-N-SH and SK-N-AS were cultured to observe the morphological impact of anlotinib. Transwell assay was used to evaluate the cell invasion, and Western blot analysis and immunohistochemistry were employed to detect the expressions of neuronal differentiation-related proteins. Results indicate that anlotinib effectively inhibited tumor growth in the PDX model, modulated the expressions of neuronal differentiation markers. In vitro, anlotinib treatment induced neurite outgrowth in neuroblastoma cells and inhibited their invasive ability, reflecting a change in neuronal marker expression patterns consistent with the PDX model. Similarly, in the SK-N-AS mouse xenograft model, anlotinib demonstrated comparable tumor-suppressing effects and promoted neuronal-like differentiation. Additionally, anlotinib significantly downregulated CRMP5 expression in neuroblastoma both in vivo and in vitro. Overexpression of CRMP5 significantly reversed the differentiation therapy effect of anlotinib, exacerbating the aggressiveness and reducing the differentiation level of neuroblastoma. These findings highlight the potential of anlotinib as an anti-neuroblastoma agent. It may suppress tumor proliferation and invasion by promoting the differentiation of tumor cells towards a neuronal-like state, and this differentiation therapy effect involves the inhibition of CRMP5 signaling.


Asunto(s)
Diferenciación Celular , Proliferación Celular , Indoles , Proteínas del Tejido Nervioso , Neuroblastoma , Quinolinas , Ensayos Antitumor por Modelo de Xenoinjerto , Humanos , Neuroblastoma/tratamiento farmacológico , Neuroblastoma/patología , Neuroblastoma/metabolismo , Neuroblastoma/genética , Animales , Ratones , Quinolinas/farmacología , Diferenciación Celular/efectos de los fármacos , Indoles/farmacología , Línea Celular Tumoral , Proteínas del Tejido Nervioso/metabolismo , Proteínas del Tejido Nervioso/genética , Proliferación Celular/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Regulación hacia Abajo/efectos de los fármacos , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Neuronas/patología , Ratones Desnudos , Hidrolasas/genética , Hidrolasas/metabolismo , Antineoplásicos/farmacología , Proteínas Asociadas a Microtúbulos
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