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1.
Sci Rep ; 11(1): 21109, 2021 10 26.
Article En | MEDLINE | ID: mdl-34702872

Cesium (Cs) is found at low levels in nature but does not confer any known benefit to plants. Cs and K compete in cells due to the chemical similarity of Cs to potassium (K), and can induce K deficiency in cells. In previous studies, we identified chemicals that increase Cs tolerance in plants. Among them, a small chemical compound (C17H19F3N2O2), named CsToAcE1, was confirmed to enhance Cs tolerance while increasing Cs accumulation in plants. Treatment of plants with CsToAcE1 resulted in greater Cs and K accumulation and also alleviated Cs-induced growth retardation in Arabidopsis. In the present study, potential target proteins of CsToAcE1 were isolated from Arabidopsis to determine the mechanism by which CsToAcE1 alleviates Cs stress, while enhancing Cs accumulation. Our analysis identified one of the interacting target proteins of CsToAcE1 to be BETA-GLUCOSIDASE 23 (AtßGLU23). Interestingly, Arabidopsis atßglu23 mutants exhibited enhanced tolerance to Cs stress but did not respond to the application of CsToAcE1. Notably, application of CsToAcE1 resulted in a reduction of Cs-induced AtßGLU23 expression in wild-type plants, while this was not observed in a high affinity transporter mutant, athak5. Our data indicate that AtßGLU23 regulates plant response to Cs stress and that CsToAcE1 enhances Cs tolerance by repressing AtßGLU23. In addition, AtHAK5 also appears to be involved in this response.


Arabidopsis Proteins/antagonists & inhibitors , Arabidopsis/enzymology , Cesium , Enzyme Inhibitors/pharmacology , Gene Expression Regulation, Plant/drug effects , beta-Glucosidase/antagonists & inhibitors , Arabidopsis/genetics , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Cesium/metabolism , Cesium/pharmacology , beta-Glucosidase/genetics , beta-Glucosidase/metabolism
2.
Molecules ; 25(24)2020 Dec 15.
Article En | MEDLINE | ID: mdl-33333961

Beta-glucosidase inhibitors play important medical and biological roles. In this study, simple two-variable artificial neural network (ANN) classification models were developed for beta-glucosidase inhibitors screening. All bioassay data were obtained from the ChEMBL database. The classifiers were generated using 2D molecular descriptors and the data miner tool available in the STATISTICA package (STATISTICA Automated Neural Networks, SANN). In order to evaluate the models' accuracy and select the best classifiers among automatically generated SANNs, the Matthews correlation coefficient (MCC) was used. The application of the combination of maxHBint3 and SpMax8_Bhs descriptors leads to the highest predicting abilities of SANNs, as evidenced by the averaged test set prediction results (MCC = 0.748) calculated for ten different dataset splits. Additionally, the models were analyzed employing receiver operating characteristics (ROC) and cumulative gain charts. The thirteen final classifiers obtained as a result of the model development procedure were applied for a natural compounds collection available in the BIOFACQUIM database. As a result of this beta-glucosidase inhibitors screening, eight compounds were univocally classified as active by all SANNs.


Drug Evaluation, Preclinical/methods , Enzyme Inhibitors/pharmacology , Neural Networks, Computer , beta-Glucosidase/antagonists & inhibitors , Enzyme Inhibitors/chemistry , Models, Molecular , Protein Conformation , Quantitative Structure-Activity Relationship , beta-Glucosidase/chemistry
3.
Molecules ; 25(19)2020 Oct 02.
Article En | MEDLINE | ID: mdl-33023214

Pharmacological chaperones (PCs) are small compounds able to rescue the activity of mutated lysosomal enzymes when used at subinhibitory concentrations. Nitrogen-containing glycomimetics such as aza- or iminosugars are known to behave as PCs for lysosomal storage disorders (LSDs). As part of our research into lysosomal sphingolipidoses inhibitors and looking in particular for new ß-galactosidase inhibitors, we report the synthesis of a series of alkylated azasugars with a relative "all-cis" configuration at the hydroxy/amine-substituted stereocenters. The novel compounds were synthesized from a common carbohydrate-derived piperidinone intermediate 8, through reductive amination or alkylation of the derived alcohol. In addition, the reaction of ketone 8 with several lithium acetylides allowed the stereoselective synthesis of new azasugars alkylated at C-3. The activity of the new compounds towards lysosomal ß-galactosidase was negligible, showing that the presence of an alkyl chain in this position is detrimental to inhibitory activity. Interestingly, 9, 10, and 12 behave as good inhibitors of lysosomal ß-glucosidase (GCase) (IC50 = 12, 6.4, and 60 µM, respectively). When tested on cell lines bearing the Gaucher mutation, they did not impart any enzyme rescue. However, altogether, the data included in this work give interesting hints for the design of novel inhibitors.


Carbohydrates/chemistry , Drug Design , Enzyme Inhibitors/pharmacology , Ketones/chemistry , Piperidines/chemical synthesis , Piperidines/pharmacology , beta-Galactosidase/antagonists & inhibitors , beta-Glucosidase/antagonists & inhibitors , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/chemistry , Humans , Leukocytes/drug effects , Leukocytes/metabolism , Piperidines/chemistry
4.
Eur J Pharmacol ; 884: 173446, 2020 Oct 05.
Article En | MEDLINE | ID: mdl-32739173

Amyotrophic lateral sclerosis (ALS) is the most common motor neuron disease in adults. While it is primarily characterized by the death of upper and lower motor neurons, there is a significant metabolic component involved in the progression of the disease. Two-thirds of ALS patients have metabolic alterations that are associated with the severity of symptoms. In ALS, as in other neurodegenerative diseases, the metabolism of glycosphingolipids, a class of complex lipids, is strongly dysregulated. We therefore assume that this pathway constitutes an interesting avenue for therapeutic approaches. We have shown that the glucosylceramide degrading enzyme, glucocerebrosidase (GBA) 2 is abnormally increased in the spinal cord of the SOD1G86R mouse model of ALS. Ambroxol, a chaperone molecule that inhibits GBA2, has been shown to have beneficial effects by slowing the development of the disease in SOD1G86R mice. Currently used in clinical trials for Parkinson's and Gaucher disease, ambroxol could be considered as a promising therapeutic treatment for ALS.


Ambroxol/pharmacology , Amyotrophic Lateral Sclerosis/drug therapy , Drug Repositioning , Enzyme Inhibitors/pharmacology , Nerve Degeneration , Neuroprotective Agents/pharmacology , Spinal Cord/drug effects , beta-Glucosidase/antagonists & inhibitors , Amyotrophic Lateral Sclerosis/enzymology , Amyotrophic Lateral Sclerosis/genetics , Amyotrophic Lateral Sclerosis/pathology , Animals , Disease Models, Animal , Disease Progression , Glucosylceramidase/antagonists & inhibitors , Glucosylceramidase/metabolism , Humans , Mutation , Spinal Cord/enzymology , Spinal Cord/pathology , Superoxide Dismutase-1/genetics , beta-Glucosidase/metabolism
5.
Int J Biol Macromol ; 153: 256-263, 2020 Jun 15.
Article En | MEDLINE | ID: mdl-32142842

The phycocyanin was purified by Sephadex- G-100 and RP-HPLC and protein content was found to be 52.82% and the high purity fraction was collected and RP-HPLC analysis of fractionated phycocyanin, the α-subunit and ß-subunit were detected in 4.9 and 11.1(mAU). The frequency of peak 1456.26 cm-1 has showed the CH2 bending vibration and the protein amide II band was detected at 1539.20 cm-1 (CO stretching) and 2358.94 cm-1. In 1H NMR analysis, 14 chemical shifts (δ) were observed and signals confirmed namely alkyl halide, alkene, aldehyde proton and carboxylic acid. The in vivo anticancer effect was assessed by MTT assay against HepG-2 cell lines and in vivo antidiabetic effect was carried out through α-amylase and ß-glucosidase enzyme inhibition methods. The promising anticancer effect 68% was noticed at the concentration of 500 µg/ml and lower anticancer effect was noticed at the concentration of 100 µg/ml against Hep-G2 cell lines. The α-amylase and ß-glucosidase enzyme inhibition of phycocyanin showed dose dependent and maximum inhibition effect at 250 µg/ml. Phycocyanin anti-inflammatory effect such as inhibition of albumin denaturation, antiproteinase, hypotonicity-induced haemolysis and anti-lipoxygenase activities have been recorded maximum level at 500 µg/ml. Phycocyanin have complex structure and high molecular weight with more biomedical applications for drug development.


Phycocyanin/chemistry , Phycocyanin/pharmacology , Spirulina/chemistry , Animals , Anti-Inflammatory Agents/chemistry , Anti-Inflammatory Agents/isolation & purification , Anti-Inflammatory Agents/pharmacology , Antineoplastic Agents/chemistry , Antineoplastic Agents/isolation & purification , Antineoplastic Agents/pharmacology , Chlorocebus aethiops , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/isolation & purification , Enzyme Inhibitors/pharmacology , Hep G2 Cells , Humans , Hypoglycemic Agents/chemistry , Hypoglycemic Agents/isolation & purification , Hypoglycemic Agents/pharmacology , Phycocyanin/isolation & purification , Vero Cells , alpha-Amylases/antagonists & inhibitors , beta-Glucosidase/antagonists & inhibitors
6.
Colloids Surf B Biointerfaces ; 188: 110800, 2020 Apr.
Article En | MEDLINE | ID: mdl-31958620

In this study, a simple and efficient method to obtain entrapment of mixtures of double enzymes is developed. As a proof of principle, double enzymes (tyrosinase (TYR) and ß-glucosidase (ß-Glu)) were co-immobilized in magnetic alginate-polydopamine (PDA) beads using in situ TYR-mediated dopamine polymerization and internal setting strategy-mediated magnetic alginate-PDA gelation. The leakage of enzymes from the magnetic alginate beads was significantly reduced by exploiting the double network cross-linking of alginate and PDA, which was induced by the d-(+)-Gluconic acid δ-lactone (GDL) and TYR, respectively. The physicochemical properties of the prepared magnetic alginate beads were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis. After that, the enzymatic reaction conditions and the performance of the entrapped TYR and ß-Glu, such as enzyme kinetics and inhibition kinetics, were investigated. The Michaelis-Menten constants (Km) of the entrapped TYR and ß-Glu were determined as 2.72 and 3.45 mM, respectively. The half-maximal inhibitory concentrations (IC50) of kojic acid and castanospermine for the entrapped TYR and ß-Glu were determined as 13.04 and 56.23 µM, respectively. Finally, the entrapped double enzymes magnetic alginate beads were successfully applied to evaluate the inhibitory potency of six kinds of tea polyphenols extracts. Black tea and white tea showed high inhibition activity against TYR were (36.14 ± 1.43)% and (36.76 ± 2.35)%, respectively, while the black tea and dark tea showed high inhibition activity against ß-Glu were (37.89 ± 6.70)% and (21.28 ± 4.68)%, respectively.


Alginates/metabolism , Dopamine/metabolism , Magnetite Nanoparticles/chemistry , Monophenol Monooxygenase/metabolism , beta-Glucosidase/metabolism , Alginates/chemical synthesis , Alginates/chemistry , Capsules/chemistry , Capsules/metabolism , Dopamine/chemistry , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Enzymes, Immobilized/antagonists & inhibitors , Enzymes, Immobilized/chemistry , Enzymes, Immobilized/metabolism , Molecular Structure , Monophenol Monooxygenase/antagonists & inhibitors , Monophenol Monooxygenase/chemistry , Particle Size , Plant Extracts/chemistry , Plant Extracts/pharmacology , Polymerization , Polyphenols/chemistry , Polyphenols/pharmacology , Surface Properties , Tea/chemistry , beta-Glucosidase/antagonists & inhibitors , beta-Glucosidase/chemistry
7.
Appl Biochem Biotechnol ; 190(3): 826-838, 2020 Mar.
Article En | MEDLINE | ID: mdl-31493157

ß-Glucosidase (BG) hydrolyzes cellobiose into glucose, and is a vital step in converting ionic liquids (ILs)-pretreated biomass to sustainable biofuels. The inactivation mechanism of BG from Paenibacillus sp. LLZ1 induced by microcrystalline cellulose was explored in various concentrations of ILs, composed of [Emim]+ cation and [DEP]-, [OAc]-, [Br]-, [Cl]-, and [BF4]- anions. The FTIR analysis of inactivated BG indicated that the ILs altered its ß-sheet content. Moreover, circular dichroism spectroscopy (CD) suggested that the α-helix content decreased, while the ß-sheet content increased with the presence of ILs in general. Interestingly, the secondary structure of BG had almost no change after [Emim]DEP treatment, while ionic liquid [Emim]BF4 treatment caused the irreversible denaturation of BG. Eventually, by adding 0.4 mM of Aerosol OT surfactant, the BG activity was increased by 20.1% in the presence of 25% [Emim]DEP, and the corresponding glucose yield from hydrolysis of cellobiose was increased by 23.9%.


Enzyme Inhibitors/pharmacology , Imidazoles/pharmacology , Ionic Liquids/pharmacology , Paenibacillus/enzymology , Surface-Active Agents/chemistry , beta-Glucosidase/antagonists & inhibitors , Enzyme Induction , Imidazoles/chemistry , Ionic Liquids/chemistry , beta-Glucosidase/biosynthesis , beta-Glucosidase/metabolism
8.
Curr Drug Discov Technol ; 17(2): 197-202, 2020.
Article En | MEDLINE | ID: mdl-30156162

BACKGROUND: In medicinal chemistry, the discovery of small organic molecules that can be optimized and lead to a future drug capable of effectively modulating the biological activity of a therapeutic target remains a major challenge. Because of the harmful secondary effects of synthesized therapeutic molecules, the development of research has been oriented towards phytomedicines. Phenolic compounds from medicinal plants are constantly explored for new therapeutic use. METHODS: In this paper, we studied interactions between main enzymes responsible for causing type 2 diabetes mellitus (T2DM) and phenolic compounds from nettle (Urtica dioica L.) using molecular Docking with Molecular Operating Environment Software (MOE). RESULTS: Docking results show a common molecule (secoisolariciresinol), which may form stable complexes with depeptidyl peptidase 4 (DPP-4), alpha-amylase and beta-glucosidase with binding energy of -7.04732084 kcal/mol, -3.82946181 kcal/mol and -4.16077089 kcal/mol respectively. Besides secoisolariciresinol, other phenolic compounds give better docking score than the original co-crystallized ligand for alpha-amylase (PDB ID 5U3A) and beta-glucosidase (PDB ID 1OGS). CONCLUSION: The obtained results are promising for the discovery of new alpha-amylase and betaglucosidase inhibitors. This study also confirms the folk use of nettle as antidiabetic agent.


Butylene Glycols/pharmacology , Diabetes Mellitus, Type 2/drug therapy , Hypoglycemic Agents/pharmacology , Lignans/pharmacology , Plant Extracts/pharmacology , Urtica dioica/chemistry , Blood Glucose/metabolism , Butylene Glycols/chemistry , Butylene Glycols/therapeutic use , Crystallography, X-Ray , Diabetes Mellitus, Type 2/enzymology , Dipeptidyl Peptidase 4/metabolism , Dipeptidyl Peptidase 4/ultrastructure , Drug Discovery/methods , Humans , Hypoglycemic Agents/chemistry , Hypoglycemic Agents/therapeutic use , Insulin/metabolism , Lignans/chemistry , Lignans/therapeutic use , Molecular Docking Simulation , Plant Extracts/chemistry , Plant Extracts/therapeutic use , alpha-Amylases/antagonists & inhibitors , alpha-Amylases/metabolism , alpha-Amylases/ultrastructure , beta-Glucosidase/antagonists & inhibitors , beta-Glucosidase/metabolism , beta-Glucosidase/ultrastructure
9.
Methods Mol Biol ; 2089: 179-189, 2020.
Article En | MEDLINE | ID: mdl-31773655

Enzymatic bioautography enables the detection of enzyme inhibitors absorbed on a thin-layer chromatography plate. Therefore, it is an assay format that is particularly useful for the detection of inhibitors present in complex mixtures. The inhibition properties of compounds separated by thin-layer chromatography can be directly analyzed to produce an inhibition profile. Here, we describe the conditions to detect inhibitor of the enzymes xanthine oxidase and ß-glucosidase immobilized on agar gel.


Chromatography, Thin Layer/methods , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Agar/chemistry , Xanthine Oxidase/antagonists & inhibitors , beta-Glucosidase/antagonists & inhibitors
10.
Luminescence ; 35(2): 222-230, 2020 Mar.
Article En | MEDLINE | ID: mdl-31713314

Energy transfer engineering based on fluorescent probes for directly sensing enzyme activities are in great demand as enzyme-mediated transformations, which are central to all biological processes. Here, a fluorescence carbon dot (CD)-based assay exhibiting selective responses to the quantitation of ß-glucosidase and the effect of its inhibitor was developed. The most common substrate, para-nitrophenyl-ß-d-glucopyranoside (pNPG) was hydrolyzed by ß-glucosidase to release p-nitrophenol (pNP), which can efficiently quench fluorescence of CDs via an inner filter effect and electron transfer. However, in the presence of inhibitors of ß-glucosidase, the fluorescence intensity gradually recovered as the concentration of inhibitors increased. Therefore, the enzyme-triggered fluorescence turn-off/turn-on of specific CDs successfully achieved sensitive detection of ß-glucosidase and monitored the effect of its inhibitors. This new strategy was applied to detect ß-glucosidase and monitor ß-glucosidase inhibitor in hepatoma cells using cell imaging. All results suggest that the new method is sensitive and promising for use in cancer diagnosis and treatment.


Carbon/metabolism , Carcinoma, Hepatocellular/diagnostic imaging , Glycoside Hydrolase Inhibitors/pharmacology , Liver Neoplasms/diagnostic imaging , Quantum Dots/metabolism , beta-Glucosidase/antagonists & inhibitors , beta-Glucosidase/analysis , Carbon/chemistry , Fluorescence , Glycoside Hydrolase Inhibitors/chemistry , Hep G2 Cells , Humans , Optical Imaging , Quantum Dots/chemistry , Spectrometry, Fluorescence , Spectrophotometry, Ultraviolet , Tumor Cells, Cultured , beta-Glucosidase/metabolism
11.
Mikrochim Acta ; 186(12): 806, 2019 11 19.
Article En | MEDLINE | ID: mdl-31745660

A fluorescent "turn off-on" nanoprobe is described for highly sensitive and selective determination of the activity of the enzyme ß-glucosidase (ß-Glu). Firstly, cysteine modified CuInS2 quantum dots (Cys-CuInS2 QDs) were prepared from indium(III) and copper(II) salts and the presence of thiourea. The red fluorescence of the Cys-CuInS2 QDs, with excitation/emission maxima at 590/656 nm, is quenched by Cu(II). However, in the presence of ß-Glu and the cyanogenic glycoside, enzymatic hydrolysis leads to the formation of cyanide. The latter competitively binds to Cu(II) owing to its high affinity for cyanide. This restores the fluorescence of the Cys-CuInS2 QDs. Under the optimum conditions, fluorescence increases linearly in the 0.5-700 U·L-1 ß-Glu activity range. The detection limit is 0.2 U·L-1. The nanoprobe was applied to analyze spiked soil samples, and satisfactory results were obtained. The average recoveries of ß-Glu were in the range of 96-103%, and the RSD was lower than 4.0%. The fluorescent probe can also be used to screen for ß-Glu inhibitors as demonstrated for castanospermine as an example. Graphical abstractSchematic representation of the fluorescent nanoprobe for ß-glucosidase activity detection and inhibitor screening by taking advantage of the fluorescence (FL) "turn-off" and "turn-on" feature of cysteine capped CuInS2 quantum dots (Cys-CuInS2 QDs).


Copper/chemistry , Fluorescent Dyes/chemistry , Indium/chemistry , Quantum Dots/chemistry , Sulfides/chemistry , beta-Glucosidase/analysis , Amygdalin/chemistry , Cyanides/chemistry , Cysteine/chemistry , Glycoside Hydrolase Inhibitors/chemistry , Indolizines/chemistry , Limit of Detection , Soil/chemistry , Spectrometry, Fluorescence/methods , beta-Glucosidase/antagonists & inhibitors
12.
Biotechnol Prog ; 35(6): e2890, 2019 11.
Article En | MEDLINE | ID: mdl-31374157

ß-Glucosidases from two different commercial preparations, Pectinex Ultra SP-L and Celluclast® 1.5L, were immobilized on divinylsulfone (DVS) supports at pH 5.0, 7.0, 9.0, and 10. In addition, the biocatalysts were also immobilized in agarose beads activated by glyoxyl, and epoxide as reagent groups. The best immobilization results were observed using higher pH values on DVS-agarose, and for Celluclast® 1.5L, good results were also obtained using the glyoxil-agarose immobilization. The biocatalyst obtained using Pectinex Ultra SP-L showed the highest thermal stability, at 65°C, and an operational stability of 67% of activity after 10 reuses cycles when immobilized on DVS-agarose immobilized at pH 10 and blocked with ethylenediamine. The ß-glucosidase from Celluclast® 1.5L produced best results when immobilized on DVS-agarose immobilized at pH 9 and blocked with glycine, reaching 7.76-fold higher thermal stability compared to its free form and maintaining 76% of its activity after 10 successive cycles. The new biocatalysts obtained by these protocols showed reduction of glucose inhibition of enzymes, demonstrating the influence of immobilization protocols, pH, and blocking agent.


Biocatalysis , Enzymes, Immobilized/metabolism , beta-Glucosidase/metabolism , Enzyme Stability , Glucose/pharmacology , Hydrogen-Ion Concentration , beta-Glucosidase/antagonists & inhibitors , beta-Glucosidase/chemistry
13.
Org Biomol Chem ; 17(30): 7204-7214, 2019 08 14.
Article En | MEDLINE | ID: mdl-31317164

A series of analogs of the iminosugars 1-deoxynojirimycin (DNJ) and 1-deoxymannojirimycin (DMJ), in which an extra five or six-membered ring has been fused to the C1-C2 bond have been prepared. The synthetic strategy exploits a key 2-keto-C-allyl iminosugar, easily accessible from gluconolactam, which upon Grignard addition and RCM furnishes a bicyclic scaffold that can be further hydroxylated at the C[double bond, length as m-dash]C bond. This strategy furnished DNJ mimics with the piperidine ring locked in a 1C4 conformation with all substituents in axial orientation when fused to a six-membered ring. Addition of an extra ring to DNJ and DMJ motif proved to strongly modify the glycosidase inhibition profile of the parent iminosugars leading to modest inhibitors. The 2-keto-C-allyl iminosugar scaffold was further used to access N-acetylglycosamine analogs via oxime formation.


1-Deoxynojirimycin/pharmacology , Glycoside Hydrolase Inhibitors/pharmacology , alpha-Glucosidases/metabolism , beta-Glucosidase/antagonists & inhibitors , 1-Deoxynojirimycin/chemical synthesis , 1-Deoxynojirimycin/chemistry , Animals , Cattle , Coffee/enzymology , Dose-Response Relationship, Drug , Glycoside Hydrolase Inhibitors/chemical synthesis , Glycoside Hydrolase Inhibitors/chemistry , Liver/enzymology , Molecular Conformation , Oryza/enzymology , Structure-Activity Relationship , beta-Glucosidase/metabolism
14.
Eur J Oral Sci ; 127(5): 472-475, 2019 10.
Article En | MEDLINE | ID: mdl-31361368

Dental biofilm - in which a diverse set of microorganisms are embedded in a complex polysaccharide matrix that adheres to oral components - is one of the most complex microbial communities in the human body. As biofilm formation is related to oral infections, such as caries and periodontal diseases, strategies for biofilm control are crucial for maintaining oral health. Xylitol, a synthetic sugar used as a sucrose substitute, has been shown to reduce biofilm formation. However, its precise mechanism of action on biofilm reduction has so far not been elucidated. Previous studies demonstrate that bacterial ß-glucosidase action is crucial for biofilm formation. Here, we investigated the correlation between salivary ß-glucosidase activity and dental plaque occurrence. We found a positive correlation between enzymatic activity and the presence of dental biofilm. We observed that xylitol inhibits ß-glucosidase in human saliva. Kinetic studies also confirmed that xylitol acts as a mixed type inhibitor of salivary ß-glucosidase. Based on our data, we suggest that xylitol impairs oral biofilm formation by the inhibition of bacterial ß-glucosidase, which is essential for biofilm formation in the oral cavity.


Bacterial Proteins/analysis , Biofilms/growth & development , Dental Plaque , Saliva/enzymology , Xylitol/pharmacology , beta-Glucosidase/analysis , Bacterial Proteins/antagonists & inhibitors , Dental Caries , Humans , Kinetics , beta-Glucosidase/antagonists & inhibitors
15.
Int J Biol Macromol ; 136: 1052-1059, 2019 Sep 01.
Article En | MEDLINE | ID: mdl-31199970

ß-Glucosidase is the rate-limiting component of a cellulase-hydrolyzing reaction. Thermostability and glucose-tolerance are two critical criteria of the enzyme, which practically determine its performance in industrial applications. In this study, a thermostable and glucose-tolerant ß-glucosidase (named Bgl1317) belonging to the glycoside hydrolase family 1 was acquired from a metagenomic library of Turpan soil through functional screening. Bgl1317 showed excellent thermostability and glucose-tolerance and its crystal structure was subsequently determined at a high resolution. Rational design based on the structure was conducted, producing three beneficial mutations A397R, L188A and A262S. While A397R improved the cellobiose activity by 80%, L188A and A262S increased the IC50 value of glucose from 0.8 to 1.5 M. The residues that may play a role in glucose-tolerance of GH1 ß-glucosidases were summarized and the performances of glucose-tolerant ß-glucosidases reported in recent years were discussed and compared. This study provides insights into enzymatic properties of Bgl1317 for engineering it into a powerful catalyst and ß-glucosidases in general.


Cellobiose/metabolism , Glucose/pharmacology , Mutagenesis, Site-Directed , Temperature , beta-Glucosidase/genetics , beta-Glucosidase/metabolism , Amino Acid Sequence , Dose-Response Relationship, Drug , Enzyme Stability , Hydrolysis , Inhibitory Concentration 50 , Kinetics , Models, Molecular , Protein Conformation , beta-Glucosidase/antagonists & inhibitors , beta-Glucosidase/chemistry
16.
Bioorg Chem ; 89: 103026, 2019 08.
Article En | MEDLINE | ID: mdl-31226649

The synthesis of multivalent pyrrolidine iminosugars via CuAAC click reaction between different pyrrolidine-azide derivatives and tri- or hexavalent alkynyl scaffolds is reported. The new multimeric compounds, together with the monomeric reference, were evaluated as inhibitors against two homologous GH1 ß-glucosidases (BglA and BglB from Paenibacillus polymyxa). The multivalent inhibitors containing an aromatic moiety in the linker between the pyrrolidine and the scaffold inhibited the octameric BglA (µM range) but did not show affinity against the monomeric BglB, despite the similarity between the active site of both enzymes. A modest multivalent effect (rp/n = 12) was detected for the hexavalent inhibitor 12. Structural analysis of the complexes between the monomeric and the trimeric iminosugar inhibitors (4 and 10) and BglA showed the insertion of the inhibitors at the active site of BglA, confirming a competitive mode of inhibition as indicated by enzyme kinetics. Additionally, structural comparison of the BglA/4 complex with the reported BglB/2F-glucose complex illustrates the key determinants responsible for the inhibitory effect and explains the reasons of the inhibition of BglA and the no inhibition of BglB. Potential inhibition of other ß-glucosidases with therapeutic relevance is discussed under the light of these observations.


Enzyme Inhibitors/pharmacology , Imino Sugars/pharmacology , Pyrrolidines/pharmacology , beta-Glucosidase/antagonists & inhibitors , Crystallography, X-Ray , Dose-Response Relationship, Drug , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/chemistry , Imino Sugars/chemical synthesis , Imino Sugars/chemistry , Models, Molecular , Molecular Structure , Paenibacillus polymyxa/enzymology , Pyrrolidines/chemical synthesis , Pyrrolidines/chemistry , Structure-Activity Relationship , beta-Glucosidase/isolation & purification , beta-Glucosidase/metabolism
17.
Int J Biol Macromol ; 136: 1133-1141, 2019 Sep 01.
Article En | MEDLINE | ID: mdl-31220494

ß-glucosidases (BGLs) hydrolyze short-chain cellulooligosaccharides. Some BGLs can hydrolyze anthocyanins and be applied in the clarification process of food industries, especially grape juice and wine. Enzyme immobilization is a valuable tool to increase enzyme stabilization. In this work, Malbranchea pulchella BGL was immobilized on Monoaminoethyl-N-ethyl-agarose ionic support, MANAE-agarose, and Concanavalin A-Sepharose affinity support, Con-A-Sepharose. The formed biocatalysts, denominated BLG-MANAE and BLG-ConA, were applied in the grape juice and red wine clarification. BGL-MANAE and BGL-ConA hyperactivated M. pulchella BGL 10- and 3-fold, respectively. Both biocatalysts showed at least 70% activity at pH range 2-11, until 24 h incubation. BGL-MANAE and BGL-ConA showed activity of 60% and 100%, respectively, at 50 °C, up to 24 h. Both biocatalysts were efficiently reused 20-fold. They were stable in the presence of up to 0.1 M glucose for 24 h incubation, and with 5%, 10% and 15% ethanol kept up to 70% activity. BGL-MANAE biocatalyst was 11% and 25% more efficient than BGL-ConA in clarification of concentrate and diluted wines, respectively. Likewise, BGL-MANAE biocatalysts were 14% and 33% more efficient than the BGL-ConA in clarification of diluted and concentrated juices, respectively. Therefore, the BGL-MANAE biocatalyst was especially effective in red wine and grape juice clarification.


Anthocyanins/metabolism , Ascomycota/enzymology , Fruit and Vegetable Juices/analysis , Sepharose/analogs & derivatives , Vitis/chemistry , Wine/analysis , beta-Glucosidase/metabolism , Biocatalysis , Enzyme Activation , Enzyme Stability , Enzymes, Immobilized/antagonists & inhibitors , Enzymes, Immobilized/chemistry , Enzymes, Immobilized/metabolism , Glucose/pharmacology , Hydrogen-Ion Concentration , Hydrolysis , Sepharose/chemistry , Temperature , beta-Glucosidase/antagonists & inhibitors , beta-Glucosidase/chemistry
18.
Biomolecules ; 9(6)2019 06 06.
Article En | MEDLINE | ID: mdl-31174354

The biomass to biofuels production process is green, sustainable, and an advanced technique to resolve the current environmental issues generated from fossil fuels. The production of biofuels from biomass is an enzyme mediated process, wherein ß-glucosidase (BGL) enzymes play a key role in biomass hydrolysis by producing monomeric sugars from cellulose-based oligosaccharides. However, the production and availability of these enzymes realize their major role to increase the overall production cost of biomass to biofuels production technology. Therefore, the present review is focused on evaluating the production and efficiency of ß-glucosidase enzymes in the bioconversion of cellulosic biomass for biofuel production at an industrial scale, providing its mechanism and classification. The application of BGL enzymes in the biomass conversion process has been discussed along with the recent developments and existing issues. Moreover, the production and development of microbial BGL enzymes have been explained in detail, along with the recent advancements made in the field. Finally, current hurdles and future suggestions have been provided for the future developments. This review is likely to set a benchmark in the area of cost effective BGL enzyme production, specifically in the biorefinery area.


Biofuels/microbiology , Biomass , beta-Glucosidase/metabolism , Animals , Biocatalysis , Enzyme Inhibitors/pharmacology , Humans , beta-Glucosidase/antagonists & inhibitors
19.
Eur J Med Chem ; 175: 63-71, 2019 Aug 01.
Article En | MEDLINE | ID: mdl-31075609

In the frame of a research program aimed to explore the relationship between chirality of iminosugars and their therapeutic potential, herein we report the synthesis of N-akyl l-deoxyiminosugars and the evaluation of the anti-inflammatory properties of selected candidates for the treatment of Pseudomonas aeruginosa infections in Cystic Fibrosis (CF) lung disease. Target glycomimetics were prepared by the shortest and most convenient approach reported to date, relying on the use of the well-known PS-TPP/I2 reagent system to prepare reactive alkoxyalkyl iodides, acting as key intermediates. Iminosugars ent-1-3 demonstrated to efficiently reduce the inflammatory response induced by P. aeruginosa in CuFi cells, either alone or in synergistic combination with their d-enantiomers, by selectively inhibiting NLGase. Surprisingly, the evaluation in murine models of lung disease showed that the amount of ent-1 required to reduce the recruitment of neutrophils was 40-fold lower than that of the corresponding d-enantiomer. The remarkably low dosage of the l-iminosugar, combined with its inability to act as inhibitor for most glycosidases, is expected to limit the onset of undesired effects, which are typically associated with the administration of its d-counterpart. Biological results herein obtained place ent-1 and congeners among the earliest examples of l-iminosugars acting as anti-inflammatory agents for therapeutic applications in Cystic Fibrosis.


Anti-Bacterial Agents/therapeutic use , Cystic Fibrosis/complications , Imino Sugars/therapeutic use , Pseudomonas Infections/complications , Pseudomonas Infections/drug therapy , Pseudomonas aeruginosa/isolation & purification , Animals , Anti-Bacterial Agents/administration & dosage , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Inflammatory Agents/administration & dosage , Anti-Inflammatory Agents/pharmacology , Bronchi/immunology , Bronchi/microbiology , Bronchi/pathology , Dose-Response Relationship, Drug , Humans , Imino Sugars/administration & dosage , Imino Sugars/chemistry , Imino Sugars/pharmacology , Inflammation/prevention & control , Inhibitory Concentration 50 , Mice , Neutrophils/immunology , Pseudomonas Infections/microbiology , Pseudomonas aeruginosa/drug effects , Stereoisomerism , beta-Glucosidase/antagonists & inhibitors
20.
J Biotechnol ; 294: 73-80, 2019 Mar 20.
Article En | MEDLINE | ID: mdl-30796944

ß-glucosidases are glycoside hydrolases that-particularly those from filamentous fungi-have been extensively explored in cellulose fiber saccharification and wine quality improvement. However, these enzymes from yeast have been poorly studied. In this study, an ethanol-glucose tolerant ß-glucosidase that is secreted by Pichia guilliermondii (current name Meyerozyma guilliermondii) was purified and characterized. This enzyme exhibited an estimated molecular mass of 97 kDa and the highest activity between pH 3.5-5.5 and 55 °C. The ß-glucosidase was also tolerant to acetone, ethanol, isopropanol, and methanol up to 30% and glucose at 1 M. It was also stable up to 55 °C for 80 min, maintaining 70% of its initial activity and in a wide pH range (pH 3-10). The enzyme exhibited 90-100% of its initial activity for 72 h at 20, 25, and 30 °C in presence of 10% ethanol at pH 3.5, which is a similar condition to winemaking. Studies that identify new enzymes and describe their purification are required for oenology applications. The ß-glucosidase described herein is a promising candidate for use in the preparation of wine. Additionally, its tolerance to glucose is an important biochemical property that adds value to this enzyme and enables it to be used during the final saccharification process.


Pichia/enzymology , beta-Glucosidase , Cellulose/chemistry , Ethanol/chemistry , Glucose/chemistry , Hydrogen-Ion Concentration , Hydrolysis , Temperature , Wine , beta-Glucosidase/antagonists & inhibitors , beta-Glucosidase/chemistry , beta-Glucosidase/isolation & purification
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