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1.
Pestic Biochem Physiol ; 158: 156-165, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31378352

RESUMO

Culex pipiens is a main vector for Bancroftian filariasis, Rift Valley Fever and diseases caused by other viruses, leaving several peoples with disabilities. In recent years, plant derived compounds have received much attention as potential alternatives to synthetic chemicals due to their low toxicity to mammals and environmental persistence. Twenty-one monoterpenes from different chemical groups (hydrocarbons and oxygenated products) were evaluated against Culex pipiens larvae. In addition, in vivo biochemical studies including effects on acetylcholine esterase (AChE), acid and alkaline phosphatases (ACP and ALP), total adenosine triphosphatase (ATPase) and gamma-aminobutyric acid transaminase (GABA-T) were investigated. Furthermore, in silico studies including pharmacophore elucidation, ADMET analysis and molecular docking of these compounds were performed. Among all tested monoterpenes, hydrocarbons [p-cymene, (R)-(+)-limonene and (+)-α-pinene], acetates (cinnamyl acetate, citronellyl acetate, eugenyl acetate and terpinyl acetate), alcohols [(±)-ß-citronellol and terpineol], aldehydes [citral and (1R)-(-)-myrtenal] and ketone [(R)-(+)-pulegone] exhibited the highest larval toxicity with LC50 = 14.88, 27.97, 26.13, 2.62, 3.81, 2.74, 21.65, 1.64, 21.70, 21.76, 1.68 and 1.90 mg/L after 48 h of exposure, respectively. The compounds proved a significant inhibition of all tested enzymes except total ATPase. The biochemical and molecular docking studies proved that AChE and GABA-T were the main targets for the tested monoterpenes.


Assuntos
Culex/virologia , Inseticidas/farmacologia , Monoterpenos/farmacologia , Fosfatase Alcalina/metabolismo , Animais , Culex/patogenicidade , Filariose Linfática/transmissão , Ativação Enzimática/efeitos dos fármacos , Esterases/metabolismo , Simulação de Acoplamento Molecular , Transaminases/metabolismo
2.
Nature ; 571(7765): 398-402, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31292548

RESUMO

A decline in stem cell function impairs tissue regeneration during ageing, but the role of the stem-cell-supporting niche in ageing is not well understood. The small intestine is maintained by actively cycling intestinal stem cells that are regulated by the Paneth cell niche1,2. Here we show that the regenerative potential of human and mouse intestinal epithelium diminishes with age owing to defects in both stem cells and their niche. The functional decline was caused by a decrease in stemness-maintaining Wnt signalling due to production of Notum, an extracellular Wnt inhibitor, in aged Paneth cells. Mechanistically, high activity of mammalian target of rapamycin complex 1 (mTORC1) in aged Paneth cells inhibits activity of peroxisome proliferator activated receptor α (PPAR-α)3, and lowered PPAR-α activity increased Notum expression. Genetic targeting of Notum or Wnt supplementation restored function of aged intestinal organoids. Moreover, pharmacological inhibition of Notum in mice enhanced the regenerative capacity of aged stem cells and promoted recovery from chemotherapy-induced damage. Our results reveal a role of the stem cell niche in ageing and demonstrate that targeting of Notum can promote regeneration of aged tissues.


Assuntos
Envelhecimento , Senescência Celular , Esterases/metabolismo , Mucosa Intestinal/patologia , Celulas de Paneth/metabolismo , Regeneração , Envelhecimento/fisiologia , Animais , Senescência Celular/fisiologia , Esterases/antagonistas & inibidores , Esterases/biossíntese , Feminino , Humanos , Mucosa Intestinal/fisiologia , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos , PPAR alfa/metabolismo , Celulas de Paneth/patologia , Receptores Acoplados a Proteínas-G/metabolismo , Nicho de Células-Tronco , Células-Tronco/patologia , Proteínas Wnt/antagonistas & inibidores , Via de Sinalização Wnt
3.
Inorg Chem ; 58(15): 9773-9784, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31318533

RESUMO

In recent years, transition metal complexes have been developed for catalytical degradation of a phosphate ester bond, particularly in RNA and DNA; however, less consideration has been given for development of complexes for the degradation of a phosphorothioate bond, as they are the foremost used pesticides in the environment and are toxic to human beings. In this context, we have developed copper complexes of benzimidazolium based ligands for catalytical degradation of a series of organophosphates (parathion, paraoxon, methyl-parathion) at ambient conditions. The copper complexes (assigned as N1-N3) were characterized using single X-ray crystallography which revealed that all three complexes are mononuclear and distorted square planner in geometry. Further, the solution state studies of the prepared complexes were carried out using UV-visible absorption, fluorescence spectroscopy, and cyclic voltametry. The complexes N1 and N2 have benzimidazolium ionic liquid as base attached with two 2-mercapto-benzimidazole pods, whereas complex N3 contains a nonionic ligand. The synthesized copper complexes were evaluated for their catalytic activity for degradation of organophosphates. It is interesting that the complex containing the ionic ligand efficiently degrades phosphorothioate pesticides, whereas complex N3 was not found to be appropriate for degradation due to a weaker conversion rate. The organophosphate degradation studies were monitored by recording absorbance spectra of parathion in the presence of catalyst, i.e., copper complexes with respect to time. The parathion was hydrolyzed into para-nitrophenol and diethyl thiophosphate. Moreover, to analyze the inhibition activity of the pesticides toward acetylcholine esterase enzyme in the presence of prepared metal complexes, Ellman's assay was performed and revealed that, within 20 min, the inhibition of acetylcholine esterase enzyme decreases by up to 13%.


Assuntos
Acetilcolina/metabolismo , Esterases/metabolismo , Estruturas Metalorgânicas/química , Praguicidas/química , Praguicidas/toxicidade , Fosfatos/química , Acetilcolina/análise , Benzimidazóis/química , Catálise , Cobre/química , Cristalografia por Raios X , Esterases/análise , Estruturas Metalorgânicas/síntese química , Modelos Moleculares , Estrutura Molecular , Fosfatos/toxicidade
4.
Phytochemistry ; 166: 112063, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31280091

RESUMO

Chlorogenic acids (CGAs) and the biopolymer lignin are both products of the phenylpropanoid pathway. Whereas CGAs have been reported to play a role during stress responses, lignin is a major component of secondary cell walls, providing physical strength and hydrophobicity to supportive and water-conducting tissues. Because the chemical structure of CGAs largely resembles those of some lignin intermediates and because CGAs can be converted back to hydroxycinnamoyl-CoAs in vitro, CGAs have been considered authentic intermediates of the lignin biosynthetic pathway. However, it is still unclear whether and how the CGA pool can be channeled towards the production of lignin monomers in response to developmental or environmental signals. Comprehensive studies on the catalytic activity of recombinant enzymes together with functional characterizations in planta have been very useful in understanding the potential interdependence between these two metabolic routes. Here we present the current understanding on CGA metabolism and discuss the biochemical and molecular evidence of the metabolic re-routing of CGAs towards lignin.


Assuntos
Ácido Clorogênico/metabolismo , Lignina/biossíntese , Esterases/metabolismo
5.
J Agric Food Chem ; 67(31): 8548-8558, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31266305

RESUMO

Herein, we report a double enzyme system to degrade 12 phthalate esters (PAEs), particularly bulky PAEs, such as the widely used bis(2-ethylhexyl) phthalate (DEHP), in a one-pot cascade process. A PAE-degrading bacterium, Gordonia sp. strain 5F, was isolated from soil polluted with plastic waste. From this strain, a novel esterase (GoEst15) and a mono(2-ethylhexyl) phthalate hydrolase (GoEstM1) were identified by homology-based cloning. GoEst15 showed broad substrate specificity, hydrolyzing DEHP and 10 other PAEs to monoalkyl phthalates, which were further degraded by GoEstM1 to phthalic acid. GoEst15 and GoEstM1 were heterologously coexpressed in Escherichia coli BL21 (DE3), which could then completely degrade 12 PAEs (5 mM), within 1 and 24 h for small and bulky substrates, respectively. To our knowledge, GoEst15 is the first DEHP hydrolase with a known protein sequence, which will enable protein engineering to enhance its catalytic performance in the future.


Assuntos
Proteínas de Bactérias/química , Esterases/química , Ésteres/química , Gordonia (Bactéria)/enzimologia , Ácidos Ftálicos/química , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biocatálise , Biodegradação Ambiental , Dietilexilftalato/química , Dietilexilftalato/metabolismo , Esterases/genética , Esterases/metabolismo , Ésteres/metabolismo , Gordonia (Bactéria)/genética , Gordonia (Bactéria)/isolamento & purificação , Gordonia (Bactéria)/metabolismo , Hidrólise , Ácidos Ftálicos/metabolismo , Alinhamento de Sequência , Microbiologia do Solo
6.
Chem Biol Interact ; 310: 108727, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31251899

RESUMO

O-Hexyl O-2,5-dichlorophenyl phosphoramidate (HDCP) induces delayed neuropathy in hens. It has been used as a tool to identify new A-esterase activities in animal tissues. This study shows the EDTA-resistant, Cu2+- and Zn2+-dependent hydrolysis of racemic HDCP in domestic and sea bird serum using UV/Vis spectrophotometry and chiral chromatography. The results clearly show a significant (p ˂ 0.05) Cu2+- and Zn2+-dependent HDCP hydrolysis in the serum of all bird species versus EDTA, except for the Zn2+-dependent HDCPase activity from Yucatecan quail serum. The ratio of Cu2+/Zn2+ hydrolysis varied between 1 and 7 (intraspecies) and 15.6 (interspecies). EDTA affected the Cu2+- and Zn2+-dependent HDCPase activity in the range of 37-95% and 40-50%, respectively. HDCP hydrolysis activated by Cu2+ was significantly (p ˂ 0.05) stereoselective (R-(+)-HDCP ˃ S-(-)-HDCP) in chicken and sea bird serum. Its R-(+)-HDCP/S-(-)-HDCP ratios were 6.8 and 1.6-2.8, respectively. EDTA-resistant and zinc-dependent HDCP hydrolysis were not stereospecific in all bird sera tested. The present ex vivo study reinforces the idea that bird sera have HDCPase activity that is sensitive to divalent metals, resistant to EDTA and possibly associated with the protein albumin.


Assuntos
Aves/sangue , Cobre/farmacologia , Esterases/metabolismo , Compostos Organofosforados/metabolismo , Zinco/farmacologia , Animais , Arildialquilfosfatase , Galinhas/sangue , Ácido Edético/farmacologia , Esterases/efeitos dos fármacos , Hidrólise , Estereoisomerismo
7.
Parasit Vectors ; 12(1): 310, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31227020

RESUMO

BACKGROUND: The tropical bed bug, Cimex hemipterus, is a serious indoor public health pest in tropical regions causing intense physical discomfort and mental distress to humans. At present, the application of insecticides is the major control strategy. The present study was designed to evaluate the development of resistance and resistance mechanisms in Cimex hemipterus from Kandy district, Sri Lanka. METHODS: The resistance status of the collected bed bugs was determined against the discriminative dosages of DDT, malathion, propoxur, deltamethrin and permethrin by conducting bioassays according to World Health Organization guidelines. Activities of insecticide metabolizing enzymes, i.e. esterases, glutathione S-transferases (GST) and monooxygenases, and the insensitivity of organophosphate/carbamate target site acetylcholinesterase (AChE), were evaluated by biochemical assays. Regions of the gene of the pyrethroid/DDT target site, the voltage-gated sodium channel regulatory protein (VGSC), were sequenced for possible kdr mutations. RESULTS: Survival percentages of bed bug population were 71, 68 and 51% for DDT, malathion and propoxur respectively. KT50 and KT90 values, calculated using log-probit mortality curves for deltamethrin were 62.55 and 123.96 h, respectively. These values were much higher for permethrin where KT50 was 201.10 h and the KT90 was beyond the detectable range. Results were compared with previous values reported for the same population in 2002. Resistance to propoxur has increased significantly from 11 to 51% with about a 20-fold increase in the number of individuals with elevated esterase mechanism. No significant change has occurred in malathion and DDT resistance, in GST and monooxygenase activities, and in AChE sensitivity for the past 14 years. Six kdr associated mutations (Y/L995H, V1010L, I1011F, L1014F, V1016E, L1017F/S) and a non-kdr associated mutation (A1007S mutation) were found from the α-region of the VGSC gene. Out of the kdr type mutations, only L1014F has been reported previously form C. hemipterus while the others have been reported from other insects. CONCLUSIONS: The bed bug population has developed high resistance to propoxur with increased esterase activities. KT50 for deltamethrin and permethrin has increased 125- and 20-fold, respectively, over the period 2002 to 2016. To the authors' knowledge, this is the first time that the possible involvement of a kdr type mutation in developing pyrethroid resistance in C. hemipterus has been shown in Sri Lanka.


Assuntos
Percevejos-de-Cama/genética , Genes de Insetos , Resistência a Inseticidas/genética , Inseticidas , Mutação , Animais , Percevejos-de-Cama/enzimologia , Bioensaio , Esterases/metabolismo , Malation , Permetrina , Propoxur , Sri Lanka
8.
BMC Genomics ; 20(1): 428, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31138111

RESUMO

BACKGROUND: Deciphering the molecular mechanisms mediating the chemical senses, taste, and smell has been of vital importance for understanding the nature of how insects interact with their chemical environment. Several gene families are implicated in the uptake, recognition, and termination of chemical signaling, including binding proteins, chemosensory receptors and degrading enzymes. The cotton leafworm, Spodoptera littoralis, is a phytophagous pest and current focal species for insect chemical ecology and neuroethology. RESULTS: We produced male and female Illumina-based transcriptomes from chemosensory and non-chemosensory tissues of S. littoralis, including the antennae, proboscis, brain and body carcass. We have annotated 306 gene transcripts from eight gene families with known chemosensory function, including 114 novel candidate genes. Odorant receptors responsive to floral compounds are expressed in the proboscis and may play a role in guiding proboscis probing behavior. In both males and females, expression of gene transcripts with known chemosensory function, including odorant receptors and pheromone-binding proteins, has been observed in brain tissue, suggesting internal, non-sensory function for these genes. CONCLUSIONS: A well-curated set of annotated gene transcripts with putative chemosensory function is provided. This will serve as a resource for future chemosensory and transcriptomic studies in S. littoralis and closely related species. Collectively, our results expand current understanding of the expression patterns of genes with putative chemosensory function in insect sensory and non-sensory tissues. When coupled with functional data, such as the deorphanization of odorant receptors, the gene expression data can facilitate hypothesis generation, serving as a substrate for future studies.


Assuntos
Proteínas de Insetos/genética , Spodoptera/genética , Animais , Antenas de Artrópodes/metabolismo , Encéfalo/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Esterases/genética , Esterases/metabolismo , Feminino , Perfilação da Expressão Gênica , Genes de Insetos , Proteínas de Insetos/metabolismo , Masculino , Família Multigênica , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Receptores Odorantes/genética , Receptores Odorantes/metabolismo , Spodoptera/enzimologia , Spodoptera/metabolismo , Spodoptera/fisiologia , Percepção Gustatória
9.
Aquat Toxicol ; 212: 28-36, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31048143

RESUMO

Titanium dioxide nanoparticles (TiO2 NPs) are widely used in various products and inevitably released with different sizes and forms into aquatic environment. The purpose of this study was to assess the differential immune toxicity of TiO2 NPs with size difference on mussel hemocytes using flow cytometry (FCM) assays. Hemocyte parameters, including total hemocyte count (THC), hemocyte mortality (HM), phagocytosis activity (PA), lysosomal content (LC), esterase activity (EA), mitochondrial number (MN), mitochondrial membrane potential (MMP) and reactive oxygen species content (ROS) were evaluated in the mussels Mytilus coruscus exposed to two types of TiO2 NPs (25nm & 100nm: 0.1, 1, 10 mg/L, respectively). In general, size- and concentration-dependent toxicity was pronounced with 25nm-NP and highest concentration (10mg/L) being the most toxic. Alhough a slight recovery from the TiO2 exposure was observed, significant carry-over effects were still detected. These results highlight the importance of differential size effects of metal oxide NPs on toxicity mechanisms in aquatic animals.


Assuntos
Hemócitos/efeitos dos fármacos , Mytilus/efeitos dos fármacos , Nanopartículas/toxicidade , Tamanho da Partícula , Titânio/toxicidade , Análise de Variância , Animais , Contagem de Células , Esterases/metabolismo , Hemócitos/citologia , Lisossomos/efeitos dos fármacos , Nanopartículas/ultraestrutura , Análise de Componente Principal , Poluentes Químicos da Água/toxicidade
10.
Chem Commun (Camb) ; 55(47): 6747-6750, 2019 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-31119249

RESUMO

o-Phenylazonaphthol (o-PAN) derivatives including 6-bromo-1-((4-bromophenyl)diazenyl)naphthalen-2-ol (AN-Br-OH) and 1-phenylazo-2-naphthol (AN-OH, known as Sudan I (Color Index 12055)) were synthesized to investigate their fluorogenic behaviors, in which their aggregated-induced emission (AIE) is reported. The o-PANs showed a two-photon absorption. The protection of hydroxyl groups in o-PANs was used for fluorescence imaging of esterase-expressed HepG2 cells, which is potentially suitable for sensing and two-photon cell imaging applications.


Assuntos
Esterases/metabolismo , Corantes Fluorescentes/química , Naftóis/química , Esterases/química , Corantes Fluorescentes/síntese química , Células Hep G2 , Humanos , Limite de Detecção , Microscopia de Fluorescência por Excitação Multifotônica , Naftóis/síntese química , Espectrometria de Fluorescência , Raios Ultravioleta
11.
Sci Total Environ ; 679: 12-22, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31078771

RESUMO

Pesticides are one of the most frequently anthropogenic xenobiotics detected in water. Among these, the organophosphorus pesticides (OPs) are very widely used in agriculture due to their broad spectrum of activity and their low price, but they also have high potent effects as neurotoxic compounds in non-target organisms. The aim of this study was to evaluate biomarkers acetylcholinesterase (AChE), butyrylcholinesterase (BChE), propionylcholinesterase (PChE) and carboxylesterase (CbE) in the representative Atlantic fish species Trachurus trachurus, Merluccius merluccius and Trisopterus luscus from "Rías Gallegas", a traditional Spanish fishing area. These esterase activities were evaluated in the brain, muscle and liver to determine the most adequate tissue to measure such enzymatic activities. The sensitivity of AChE and CbE activities from different tissues the widely used organophosphorus insecticide chlorpyrifos (CP), and its toxic metabolite (CP-oxon) was also tested. AChE activity was predominant in all tissues of the analysed species (particularly in brain constituting from 78.33%, 89.83% and 88.43% of total ChEs in Trachurus trachurus, Merluccius merluccius and Trisopterus luscus, respectively). Under in vitro exposure, esterases were shown to be highly sensitive to CP and especially to CP-oxon. Moreover, a similar effect observed on AChE and CbE activities could suggest that CbE activity might contribute efficiently against the toxic effects of CP, especially in muscle and the liver. The presence of BChE, PChE and upper CbE activities in muscle and the liver and their OP-sensibilities can be used to study their function in the pesticide biochemical detoxification pathways with a prominent role as a safeguarding mechanism against pesticide toxicity.


Assuntos
Clorpirifos/efeitos adversos , Esterases/metabolismo , Proteínas de Peixes/metabolismo , Gadiformes/metabolismo , Perciformes/metabolismo , Poluentes Químicos da Água/efeitos adversos , Animais , Monitoramento Ambiental , Inseticidas/efeitos adversos , Especificidade de Órgãos
12.
Appl Microbiol Biotechnol ; 103(10): 4065-4075, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30949809

RESUMO

Glucuronoyl esterases (CE15 family) enable targeted cleavage of ester linkages in lignin-carbohydrate complexes (LCCs), particularly those linking lignin and glucuronoyl residues in xylan. A substantial challenge in characterization and kinetic analysis of CE15 enzymes has been the lack of proper substrates. Here, we present an assay using an insoluble LCC-rich lignin fraction from birch; lignin-rich pellet (LRP). The assay employs quantification of enzyme reaction products by LC-MS. The kinetics of four fungal CE15 enzymes, PsGE, CuGE, TtGE, and AfuGE originating from lignocellulose-degrading fungi Punctularia strigosozonata, Cerrena unicolor, Thielavia terrestris, and Armillaria fuscipes respectively were characterized and compared using this new assay. All four enzymes had activity on LRP and showed a clear preference for the insoluble substrate compared with smaller soluble LCC mimicking esters. End-product profiles were near identical for the four enzymes but differences in kinetic parameters were observed. TtGE possesses an alternative active site compared with the three other enzymes as it has the position of the catalytic glutamic acid occupied by a serine. TtGE performed poorly compared with the other enzymes. We speculate that glucuronoyl LCCs are not the preferred substrate of TtGE. Removal of an N-terminal CBM on CuGE affected the catalytic efficiently of the enzyme by reducing Kcat by more than 30%. Reaction products were detected from all four CE15s on a similar substrate from spruce indicating a more generic GE activity not limited to the hardwood. The assay with natural substrate represents a novel tool to study the natural function and kinetics of CE15s.


Assuntos
Basidiomycota/enzimologia , Metabolismo dos Carboidratos , Esterases/metabolismo , Lignina/metabolismo , Sordariales/enzimologia , Betula/química , Cromatografia Líquida , Esterases/isolamento & purificação , Cinética , Lignina/isolamento & purificação , Espectrometria de Massas
13.
Drug Deliv ; 26(1): 416-432, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30929527

RESUMO

Nanoparticles have been developed for tumor treatment due to the enhanced permeability and retention effects. However, lack of specific cancer cells selectivity results in low delivery efficiency and undesired side effects. In that case, the stimuli-responsive nanoparticles system designed for the specific structure and physicochemical properties of tumors have attracted more and more attention of researchers. Esterase-responsive nanoparticle system is widely used due to the overexpressed esterase in tumor cells. For a rational designed esterase-responsive nanoparticle, ester bonds and nanoparticle structures are the key characters. In this review, we overviewed the design of esterase-responsive nanoparticles, including ester bonds design and nano-structure design, and analyzed the fitness of each design for different application. In the end, the outlook of esterase-responsive nanoparticle is looking forward.


Assuntos
Antineoplásicos/administração & dosagem , Nanopartículas , Neoplasias/tratamento farmacológico , Animais , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacologia , Sistemas de Liberação de Medicamentos , Desenho de Drogas , Esterases/metabolismo , Humanos , Neoplasias/enzimologia
14.
Prep Biochem Biotechnol ; 49(7): 727-734, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31017519

RESUMO

The accurate estimation of kinetic parameters is of fundamental importance for biochemical studies for research and industry. In this paper, we demonstrate the application of a modular microfluidic system for execution of enzyme assays that allow determining the kinetic parameters of the enzymatic reactions such as Vmax - the maximum rate of reaction and KM - the Michaelis constant. For experiments, the fluorogenic carbonate as a probe for a rapid determination of the kinetic parameters of hydrolases, such as lipases and esterases, was used. The microfluidic system together with the method described yields the kinetic constants calculated from the concentration of enzymatic product changes via a Michaelis-Menten model using the Lambert function W(x). This modular microfluidic system was validated on three selected enzymes (hydrolases).


Assuntos
Ensaios Enzimáticos/instrumentação , Esterases/metabolismo , Dispositivos Lab-On-A-Chip , Lipase/metabolismo , Carbonatos/análise , Carbonatos/metabolismo , Desenho de Equipamento , Esterases/análise , Fluorescência , Corantes Fluorescentes/análise , Corantes Fluorescentes/metabolismo , Cinética , Lipase/análise
15.
Nanoscale ; 11(11): 5030-5037, 2019 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-30839985

RESUMO

Tissue-specific self-assemblies of supramolecular hydrogels have attracted great interest in material design and biomedical applications, for in situ-formed hydrogels serve as an excellent local depot with tunable release of drug therapeutics. Here we report the design and syntheses of a novel class of histidine-containing hexapeptide derivatives (Nap-1 and ID-1) for in situ hydrogelation at the zinc ion-rich prostate tissue. Thanks to the efficient co-ordination between zinc and histidine, both Nap-1 and ID-1 displayed excellent self-assembly capability with a high sensitivity to zinc ions at ∼0.1 equivalency. To foster a prostate-specific drug delivery system (DDS), ID-1 was chosen for further conjugation with bicalutamide (BLT), a clinically used drug for prostate cancer. The as-synthesized ID-1-BLT retained the self-assembly capability with zinc ions, and conferred supramoelcular hydrogels at the prostate site. Interestingly, ID-1-BLT hydrogels demonstrated tunable drug release profiles in a typical tumor microenvironment, with acidic pH and esterase activity regulating the drug release in a dose dependent manner. Consequently, the hydrogel-based DDS demonstrated enhanced potency and selective cytotoxicity against prostate cancer cell DU145 over normal fibroblast cell NIH3T3, plausibly due to differential cellular uptake of drugs as well as the elevated esterase activities in cancer cells. Finally, the biocompatible hydrogel system demonstrated sustained delivery of drugs at the prostate gland of rats, with a superior in situ drug distribution profile compared to that of aqueous solution of BLT alone.


Assuntos
Anilidas/química , Sistemas de Liberação de Medicamentos , Hidrogéis/química , Nitrilos/química , Oligopeptídeos/química , Próstata/metabolismo , Compostos de Tosil/química , Anilidas/administração & dosagem , Anilidas/farmacocinética , Anilidas/farmacologia , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/farmacologia , Esterases/metabolismo , Histidina/química , Humanos , Hidrogéis/administração & dosagem , Hidrogéis/farmacocinética , Hidrogéis/farmacologia , Concentração de Íons de Hidrogênio , Masculino , Camundongos , Células NIH 3T3 , Nitrilos/administração & dosagem , Nitrilos/farmacocinética , Nitrilos/farmacologia , Próstata/efeitos dos fármacos , Ratos , Temperatura Ambiente , Compostos de Tosil/administração & dosagem , Compostos de Tosil/farmacocinética , Compostos de Tosil/farmacologia , Zinco/química
16.
Appl Microbiol Biotechnol ; 103(8): 3421-3437, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30809711

RESUMO

Owing to the functional versatility and potential applications in industry, interest in lipolytic enzymes tolerant to organic solvents is increasing. In this study, functional screening of a compost soil metagenome resulted in identification of two lipolytic genes, est1 and est2, encoding 270 and 389 amino acids, respectively. The two genes were heterologously expressed and characterized. Est1 and Est2 are thermostable enzymes with optimal enzyme activities at 80 and 70 °C, respectively. A second-order rotatable design, which allows establishing the relationship between multiple variables with the obtained responses, was used to explore the combined effects of temperature and pH on esterase stability. The response curve indicated that Est1, and particularly Est2, retained high stability within a broad range of temperature and pH values. Furthermore, the effects of organic solvents on Est1 and Est2 activities and stabilities were assessed. Notably, Est2 activity was significantly enhanced (two- to tenfold) in the presence of ethanol, methanol, isopropanol, and 1-propanol over a concentration range between 6 and 30% (v/v). For the short-term stability (2 h of incubation), Est2 exhibited high tolerance against 60% (v/v) of ethanol, methanol, isopropanol, DMSO, and acetone, while Est1 activity resisted these solvents only at lower concentrations (below 30%, v/v). Est2 also displayed high stability towards some water-immiscible organic solvents, such as ethyl acetate, diethyl ether, and toluene. With respect to long-term stability, Est2 retained most of its activity after 26 days of incubation in the presence of 30% (v/v) ethanol, methanol, isopropanol, DMSO, or acetone. All of these features indicate that Est1 and Est2 possess application potential.


Assuntos
Compostagem , Esterases/química , Esterases/metabolismo , Metagenoma/genética , Solventes/química , Sequência de Bases , Clonagem Molecular , Ativação Enzimática , Estabilidade Enzimática , Esterases/genética , Esterases/isolamento & purificação , Biblioteca Gênica , Temperatura Alta , Concentração de Íons de Hidrogênio , Lipólise , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Especificidade por Substrato
17.
Appl Microbiol Biotechnol ; 103(7): 3037-3048, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30762074

RESUMO

The thermophilic fungus Thielavia terrestris when cultured on cellulose produces a cocktail of thermal hydrolases with potential application in saccharification of lignocellulosic biomass and other biotechnological areas. Glucuronoyl esterases are considered to play a unique role as accessory enzymes in lignocellulosic material biodegradation by cleaving the covalent ester linkage between 4-O-methyl-D-glucuronic acid (MeGlcA) and lignin in lignin-carbohydrate complexes (LCCs). Two glucuronoyl esterases from T. terrestris named TtGE1 and TtGE2 were expressed in Pichia pastoris. Both esterases displayed features of thermophilic enzymes, with the optimal temperature at 45 °C and 55 °C. TtGE1 and TtGE2 exhibited activity towards methyl (4-nitrophenyl ß-D-glucopyranosid) uronate (Me-GlcA-pNP) but no catalytic activity to benzyl-D-glucuronate (BnzGlcA), indicating the difference in substrate specificity from previously studied fungal GEs. A substantial increase in the release of monomeric sugars and glucuronic acid from autohydrolysis of corn bran was observed by the supplementing TtGEs into commercial xylanase; the results clearly demonstrated that the TtGEs played a significant role in this degradation process. This research on TtGEs enriches our knowledge of this novel class of fungal GEs. These newly characterized TtGEs could be used as promising accessory enzymes to improve the hydrolysis efficiency of commercial enzymes in saccharification of lignocellulosic materials due to their thermophilic characteristics.


Assuntos
Fibras na Dieta/metabolismo , Ácido Glucurônico/metabolismo , Sordariales/enzimologia , Zea mays/metabolismo , Biomassa , Biotecnologia , Esterases/genética , Esterases/metabolismo , Ésteres/metabolismo , Proteínas Fúngicas/metabolismo , Ácido Glucurônico/genética , Hidrólise , Lignina/metabolismo , Sordariales/genética , Especificidade por Substrato
18.
J Pharm Biomed Anal ; 168: 13-22, 2019 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-30776567

RESUMO

Simvastatin is known as a pro-drug, which could be hydrolyzed by esterases to its active form, simvastatin acid. Although pharmacokinetics of simvastatin and simvastatin acid have been widely studied, hydrolysis of simvastatin to simvastatin acid during blood sampling and plasma preparation has been overlooked in the previous studies, leading to underestimation of simvastatin concentration and overestimation of simvastatin acid concentration in plasma. Since both efficacy and adverse drug reaction of simvastatin are highly dependent on simvastatin and simvastatin acid concentrations in vivo, accurate assessment of the two compounds are critical in their pharmacokinetic and pharmacodynamic studies. The current study was proposed aiming to investigate the esterase mediated hydrolysis of simvastatin in human and rat blood and its impact on the pharmacokinetic study of simvastatin and simvastatin acid. Using various esterase inhibitors including potassium florid (KF), bis(4-nitrophenyl) phosphate (BNPP), and ethylenediaminetetraacetic acid (EDTA), carboxylesterase was found to be the major esterase that hydrolyzed simvastatin in rat blood, while carboxylesterase and paraoxonase were the major esterases mediating the hydrolysis of simvastatin in human blood. Further studies using human recombinant enzymes identified simvastatin as substrates of PON1, CES1b, PON3 and CES1c with Clint of 8.75, 5.77, 3.93, and 2.45 µL/min/mg protein. Therefore, inhibition treatments with 20 mM BNPP and 50 mM KF/ 10 mM EDTA were developed to efficiently prevent the hydrolysis of simvastatin during blood sampling and plasma preparation in rat/human. The subsequent pharmacokinetics of orally administered simvastatin at 8.66 mg/kg in rats found that the Cmax and AUC0-∞ of simvastatin in absence of such esterase inhibitors in the blood sampling process were only 17.04 ± 6.60% and 15.30 ± 6.76% of those in presence of the inhibitors, whereas the Cmax and AUC0-∞ of simvastatin acid were 1.60 ± 0.30 and 1.80 ± 0.22 times of that obtained in presence of the inhibitors. Nevertheless, T1/2 of simvastatin and simvastatin acid remained the same regardless of the blood sampling method. Our current study for the first time demonstrated the importance for assessment of simvastatin stability during the blood sampling and plasma preparation process, which may be applicable to therapeutic drug monitoring of not only simvastatin but also other pro-drugs/compounds sharing similar metabolic properties.


Assuntos
Esterases/metabolismo , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Sinvastatina/análogos & derivados , Sinvastatina/administração & dosagem , Administração Oral , Animais , Área Sob a Curva , Monitoramento de Medicamentos/métodos , Inibidores Enzimáticos/farmacologia , Esterases/antagonistas & inibidores , Humanos , Hidrólise , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacocinética , Masculino , Pró-Fármacos , Ratos , Ratos Sprague-Dawley , Sinvastatina/metabolismo , Sinvastatina/farmacocinética , Especificidade da Espécie
19.
Biosci Biotechnol Biochem ; 83(6): 1124-1135, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30782084

RESUMO

(R)-2-amino-2-ethoxycarbonylsuccinimide (ASI-2) is a key intermediate used in the pharmaceutical industry and is valuable for the industrial synthesis of ranirestat, which is a potent aldose reductase inhibitor. ASI-2 was synthesized in a process combining chemical synthesis and bioconversion. Bioconversion in this study is a key reaction, since optically active carboxylic acid derivative ((R)-1-ethyl hydrogen 3-benzyloxycarbonylamino-3-ethoxycarbonylsuccinate, Z-MME-AE) is synthesized from a prochiral ester, diethyl 2-benzyloxycarbonylamino-2-ethoxycarbonylsuccinate, Z-MDE-AE, at a theoretical yield of 100%. Upon screening for microorganisms that asymmetrically hydrolyze Z-MDE-AE, Bacillus thuringiensis NBRC13866 was found. A novel esterase EstBT that produces Z-MME-AE was purified from Bacillus thuringiensis NBRC13866 and was stably produced in Escherichia coli JM109 cells. Using EstBT rather than porcine liver esterase (PLE), ASI-2 was synthesized with a 17% higher total yield by a novel method, suggesting that the esterase EstBT is a PLE substitute enzyme and therefore, may be of interest for future industrial applications.


Assuntos
Inibidores Enzimáticos/síntese química , Esterases/metabolismo , Fígado/enzimologia , Pirazinas/síntese química , Compostos de Espiro/síntese química , Sequência de Aminoácidos , Animais , Bacillus thuringiensis/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sequência de Bases , Eletroforese em Gel de Poliacrilamida , Inibidores Enzimáticos/química , Escherichia coli/genética , Hidrólise , Pirazinas/química , Proteínas Recombinantes/genética , Compostos de Espiro/química , Suínos
20.
Acta Trop ; 193: 148-157, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30742803

RESUMO

Anopheles sacharovi and Anopheles superpictus have a significant public health importance since they are primer and seconder malaria vectors of Turkey, respectively. As a result of intensive insecticide usage in historically malaria endemic regions of Turkey for long years, insecticide resistance problem has occurred inevitably. In this study, we aimed to investigate the involvement of the detoxification enzymes in insecticide resistance in Turkish An. sacharovi and An. superpictus populations in the Mediterranean and South-eastern Anatolia region where have a malaria history in the past. Bioassay results indicated that both An. sacharovi and An. superpictus populations are resistant to DDT, resistant or possible resistant to organophosphates and carbamates and finally mostly susceptible to pyrethroids. Although bioassays results indicated high DDT resistance in all mosquito populations, biochemical assays did not show significantly high GST levels in all strains. Almost all An. sacharovi and An. superpictus populations had an increased α and ß esterase activity levels while nearly half of the overall populations had an increased p-NPA esterase than the control group. Elevated levels of MFO frequency have been shown in the majority of the populations. Consequently, our results reveal that biochemical resistance mechanisms may play an important role in insecticide resistance in Turkish An. sacharovi and An. superpictus populations. These results give useful cues to monitor the insecticide resistance before it spreads throughout an entire population, enabling early intervention.


Assuntos
Anopheles/efeitos dos fármacos , Esterases/metabolismo , Resistência a Inseticidas , Inseticidas/farmacologia , Malária/epidemiologia , Mosquitos Vetores/efeitos dos fármacos , Animais , Anopheles/enzimologia , Carbamatos/farmacologia , DDT/farmacologia , Doenças Endêmicas , Feminino , Glutationa Transferase/metabolismo , Humanos , Oxigenases de Função Mista/metabolismo , Mosquitos Vetores/enzimologia , Organofosfatos/farmacologia , Piretrinas/farmacologia , Turquia/epidemiologia
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