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1.
Plant J ; 111(1): 269-281, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35506310

RESUMO

Low phosphate (LP) in soil is a common nutrient stress that severely restricts agricultural production, but the role, if any, of the major stress phytohormone abscisic acid (ABA) in plant phosphate (Pi) starvation responses remains elusive. Here, we report that LP-induced ABA accumulation promotes Pi uptake in an ABA INSENSITIVE5 (ABI5)-dependent manner in Arabidopsis thaliana. LP significantly activated plant ABA biosynthesis, metabolism, and stress responses, suggesting a role of ABA in the plant response to Pi availability. LP-induced ABA accumulation and expression of two major high-affinity phosphate transporter genes PHOSPHATE TRANSPORTER1;1/1;4 (PHT1;1/1;4) were severely impaired in a mutant lacking BETA-GLUCOSIDASE1 (BG1), which converts conjugated ABA to active ABA, and the mutant had shorter roots and less Pi content than wild-type plants under LP conditions. Moreover, a mutant of ABI5, which encodes a central transcription factor in ABA signaling, also exhibited suppressed root elongation and had reduced Pi content under LP conditions. ABI5 facilitated Pi acquisition by activating the expression of PHT1;1 by directly binding to its promoter, while overexpression of PHT1;1 completely rescued its Pi content under LP conditions. Together, our findings illustrate a molecular mechanism by which ABA positively modulates phosphate acquisition through ABI5 in the Arabidopsis response to phosphate deficiency.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Ácido Abscísico/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Regulação da Expressão Gênica de Plantas , Fosfatos/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
2.
BMC Plant Biol ; 21(1): 60, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33482727

RESUMO

BACKGROUND: Glycoalkaloids are bioactive compounds that contribute to the defence response of plants against herbivore attack and during pathogenesis. Solanaceous plants, including cultivated and wild potato species, are sources of steroidal glycoalkaloids. Solanum plants differ in the content and composition of glycoalkaloids in organs. In wild and cultivated potato species, more than 50 steroidal glycoalkaloids were recognized. Steroidal glycoalkaloids are recognized as potential allelopathic/phytotoxic compounds that may modify the growth of target plants. There are limited data on the impact of the composition of glycoalkaloids on their phytotoxic potential. RESULTS: The presence of α-solasonine and α-solamargine in potato leaf extracts corresponded to the high phytotoxic potential of the extracts. Among the differentially expressed genes between potato leaf bulks with high and low phytotoxic potential, the most upregulated transcripts in sample of high phytotoxic potential were anthocyanin 5-aromatic acyltransferase-like and subtilisin-like protease SBT1.7-transcript variant X2. The most downregulated genes were carbonic anhydrase chloroplastic-like and miraculin-like. An analysis of differentially expressed proteins revealed that the most abundant group of proteins were those related to stress and defence, including glucan endo-1,3-beta-glucosidase acidic isoform, whose expression level was 47.96× higher in potato leaf extract with low phytotoxic. CONCLUSIONS: The phytotoxic potential of potato leaf extract possessing low glycoalkaloid content is determined by the specific composition of these compounds in leaf extract, where α-solasonine and α-solamargine may play significant roles. Differentially expressed gene and protein profiles did not correspond to the glycoalkaloid biosynthesis pathway in the expression of phytotoxic potential. We cannot exclude the possibility that the phytotoxic potential is influenced by other compounds that act antagonistically or may diminish the glycoalkaloids effect.


Assuntos
Compostos Fitoquímicos/metabolismo , Extratos Vegetais/análise , Proteoma , Alcaloides de Solanáceas/metabolismo , Solanum/genética , Transcriptoma , Quimera , Perfilação da Expressão Gênica , Folhas de Planta/química , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteômica , Solanum/química , Solanum/metabolismo , Toxinas Biológicas/metabolismo
3.
Fungal Genet Biol ; 151: 103551, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33737204

RESUMO

Draft genome sequence of the glucose tolerant beta glucosidase (GT-BGL) producing rare fungus Aspergillus unguis NII 08,123 was generated through Next Generation Sequencing (NGS). The genome size of the fungus was estimated to be 37.1 Mb. A total of 3116 contigs were assembled using SPades, and 15,161 proteins were predicted using AUGUSTUS 3.1. Among them, 13,850 proteins were annotated using UniProt. Distribution of CAZyme genes specifically those encoding lignocellulose degrading enzymes were analyzed and compared with those from the industrial cellulase producer Trichoderma reesei in view of the huge differences in detectable enzyme activities between the fungi, despite the ability of A. unguis to grow on lignocellulose as sole carbon source. Full length gene sequence of the inducible GT-BGL could be identified through tracing back from peptide mass fingerprint. A total of 403 CAZymes were predicted from the genome, which includes 232 glycoside hydrolases (GHs), 12 carbohydrate esterases (CEs), 109 glycosyl transferases (GTs), 15 polysaccharide lyases (PLs), and 35 genes with auxiliary activities (AAs). The high level of zinc finger motif containing transcription factors could possibly hint a tight regulation of the cellulolytic machinery, which may also explain the low cellulase activities even when a complete repertoire of cellulase degrading enzyme genes are present in the fungus.


Assuntos
Aspergillus/genética , Genoma Fúngico , Lignina/metabolismo , beta-Glucosidase/genética , Aspergillus/enzimologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Glucose/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Hypocreales/metabolismo , beta-Glucosidase/metabolismo
4.
Molecules ; 26(7)2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33808362

RESUMO

Olive mill wastewater (OMW) contains valuable and interesting bioactive compounds, among which is hydroxytyrosol, which is characterized by a remarkable antioxidant activity. Due to the health claims related to olive polyphenols, the aim of this study was to obtain an extract from OMW with an increased level of hydroxytyrosol by means of microbial enzymatic activity. For this purpose, four commercial adsorbent resins were selected and tested. The beta-glucosidase and esterase activity of strains of Wickerhamomyces anomalus, Lactiplantibacillus plantarum, and Saccharomyces cerevisiae were also investigated and compared to those of a commercial enzyme and an Aspergillus niger strain. The W. anomalus strain showed the best enzymatic performances. The SP207 resin showed the best efficiency in selective recovery of hydroxytyrosol, tyrosol, oleuropein, and total phenols. The bioconversion test of the OMW extract was assessed by using both culture broths and pellets of the tested strains. The results demonstrated that the pellets of W. anomalus and L. plantarum were the most effective in hydroxytyrosol increasing in phenolic extract. The interesting results suggest the possibility to study new formulations of OMW phenolic extracts with multifunctional microorganisms.


Assuntos
Fungos/metabolismo , Olea/química , Fenóis/química , Extratos Vegetais/química , Eliminação de Resíduos Líquidos , beta-Glucosidase/metabolismo , Lactobacillaceae/metabolismo , Probióticos
5.
BMC Med Genet ; 21(1): 12, 2020 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-31931749

RESUMO

BACKGROUND: Gaucher disease (GD) is a lysosomal disorder caused by biallelic pathogenic mutations in the GBA1 gene that encodes beta-glucosidase (GCase), and more rarely, by a deficiency in the GCase activator, saposin C. Clinically, GD manifests with heterogeneous multiorgan involvement mainly affecting hematological, hepatic and neurological axes. This disorder is divided into three types, based on the absence (type I) or presence and severity (types II and III) of involvement of the central nervous system. At the cellular level, deficiency of GBA1 disturbs lysosomal storage with buildup of glucocerebroside. The consequences of disturbed lysosomal metabolism on biochemical pathways that require lysosomal processing are unknown. Abnormal systemic markers of cobalamin (Cbl, B12) metabolism have been reported in patients with GD, suggesting impairments in lysosomal handling of Cbl or in its downstream utilization events. METHODS: Cultured skin fibroblasts from control humans (n = 3), from patients with GD types I (n = 1), II (n = 1) and III (n = 1) and an asymptomatic carrier of GD were examined for their GCase enzymatic activity and lysosomal compartment intactness. Control human and GD fibroblasts were cultured in growth medium with and without 500 nM hydroxocobalamin supplementation. Cellular cobalamin status was examined via determination of metabolomic markers in cell lysate (intracellular) and conditioned culture medium (extracellular). The presence of transcobalamin (TC) in whole cell lysates was examined by Western blot. RESULTS: Cultured skin fibroblasts from GD patients exhibited reduced GCase activity compared to healthy individuals and an asymptomatic carrier of GD, demonstrating a preserved disease phenotype in this cell type. The concentrations of total homocysteine (tHcy), methylmalonic acid (MMA), cysteine (Cys) and methionine (Met) in GD cells were comparable to control levels, except in one patient with GD III. The response of these metabolomic markers to supplementation with hydroxocobalamin (HOCbl) yielded variable results. The content of transcobalamin in whole cell lysates was comparable in control human and GD patients. CONCLUSIONS: Our results indicate that cobalamin transport and cellular processing pathways are overall protected from lysosomal storage damage in GD fibroblasts. Extending these studies to hepatocytes, macrophages and plasma will shed light on cell- and compartment-specific vitamin B12 metabolism in Gaucher disease.


Assuntos
Doença de Gaucher/genética , Glucosilceramidase/genética , Vitamina B 12/metabolismo , beta-Glucosidase/genética , Técnicas de Cultura de Células , Feminino , Fibroblastos/metabolismo , Doença de Gaucher/metabolismo , Doença de Gaucher/patologia , Homocisteína/metabolismo , Humanos , Lisossomos/metabolismo , Lisossomos/patologia , Masculino , Ácido Metilmalônico/metabolismo , Mutação , Fenótipo , Saposinas/genética , Transcobalaminas/metabolismo
6.
Glob Chang Biol ; 26(6): 3698-3714, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32159881

RESUMO

Soil enzymes are central in the response of terrestrial ecosystems to climate change, and their study can be crucial for the models' implementation. We investigated for 1 year the effects of warming and seasonality on the potential activities of five soil extracellular enzymes and their relationships with soil moisture, phosphorus (P) concentration, and other soil parameters in a P-limited Mediterranean semiarid shrubland. The site was continuously subjected to warming since 1999, and we compared data from this study to analogous data from 2004. Warming uniformly increased all enzymes activities, but only when a sufficient amount of soil water was available. Seasonality unevenly altered enzyme activities, thus affecting enzymatic stoichiometry. P deficiency affected enzymatic stoichiometry, favoring the activities of the phosphatases. The effect of warming was stronger in 2014 than 2004, excluding the hypothesis of acclimation of rhizospheric responses to higher temperatures and suggesting that further increases in extracellular enzymatic activities are to be expected if sufficient water is available. Climatic warming will likely generally stimulate soil enzymatic activities and accelerate nutrient mineralization and similar ecological processes such as the production and degradation of biomass and changes in community composition, but which will be limited by water availability, especially in Mediterranean soils in summer. Winters in such ecosystems will benefit from a general increase in activity and production, but biological activity could even decrease in summer, potentially leading to a negative overall balance of nutrient mineralization. This study suggests that a general increase in activity due to warming could lead to faster mineralization of soil organic matter and water consumption in colder climates, until one of these factors in turn becomes limiting. Such trade-offs between water and temperature in relation with enzyme activity should be considered in biogeochemical models.


Assuntos
Ecossistema , Solo , Mudança Climática , Estações do Ano , Microbiologia do Solo
7.
Mol Biol Rep ; 47(5): 3577-3584, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32314186

RESUMO

We herein report the preparation of a full-length raucaffricine-O-beta-D-glucosidase gene of stevia rebaudiana Bertoni (named SrRG1, GenBank accession number MK920450). Sequence analysis indicated SrRG1 consists of a 1650 bp open reading frame encoding a protein of 549 amino acids. Its deduced amino acid sequence showed a high identity of 82% with a raucaffricine-O-beta-D-glucosidase from H. annuus of glycoside hydrolase family 1. The expression pattern analyzed by real-time quantitative PCR showed no significant difference among different tissues, developmental stages, and cultivars under normal growth conditions. Furthermore, the gene function of SrRG1 was preliminarily studied by agrobacterium-mediated transformation on instantaneous expression. In the test of agrobacterium-mediated transformation on instantaneous expression, it was observed that overexpression of SrRG1 increased the accumulation of steviol content and decreased the major components and total SGs contents. Such results demonstrated that SrRG1 may participate in the steviol glycosides catabolic pathway. However, the effect of silencing construct infiltration on steviol and SGs content was not significant and its expression pattern was constitutive, which most probably, attributed the hydrolysis of SGs to the secondary activity of SrRG1. This study firstly identified the bate-glucosidase in stevia and advances our understanding of steviol glycosides hydrolyzation.


Assuntos
Diterpenos do Tipo Caurano/metabolismo , Glucosídeos/metabolismo , Stevia/genética , beta-Glucosidase/metabolismo , Diterpenos do Tipo Caurano/análise , Regulação da Expressão Gênica de Plantas/genética , Glicosídeos/análise , Folhas de Planta/genética , Stevia/metabolismo , beta-Glucosidase/genética
8.
Molecules ; 25(24)2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33333961

RESUMO

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.


Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Inibidores Enzimáticos/farmacologia , Redes Neurais de Computação , beta-Glucosidase/antagonistas & inibidores , Inibidores Enzimáticos/química , Modelos Moleculares , Conformação Proteica , Relação Quantitativa Estrutura-Atividade , beta-Glucosidase/química
9.
Zhongguo Zhong Yao Za Zhi ; 43(8): 1602-1609, 2018 Apr.
Artigo em Zh | MEDLINE | ID: mdl-29751706

RESUMO

Three different beta-glycosidase sequences of Ttebgl3, Tpebgl1 and Tpengl3 from Thermotoga thermarum DSM 5069 and Thermotoga petrophila RKU-1 were analyzed. Also, the influence of temperature, pH, concentration of DMSO, metal ions and kinetic constant on catalytic conversion of baicalin had been compared. The results indicated that the optimal pH and optimum temperature for transformation of baicalin was 4.5 85 °C, 5.0 80 °C and 5.5 80 °C, respectively. The family GH3 beta-glycosidase Ttebgl3 and Tpebgl3 had the better DMSO tolerance. The activation effect of the metal ions on the catalytic conversion of baicalin was not obvious, and the inhibition of the GH3 family beta glucosidase was significantly stronger than that of the GH1 family. The kinetic constants of three different beta-glucosidases catalyzed baicalin were significantly different. The Km and Vmax values of Tpebgl1, Tpebgl3 and Ttebgl3 were 0.029 2 mmol·L⁻¹ 4.85 U·mg⁻¹, 0.268 6 mmol·L⁻¹ 121.04 U·mg⁻¹ and 0.391 8 mmol·L⁻¹ 308.90 U·mg⁻¹, respectively. Family GH3 beta-glycosidase converted more baicalin than family GH1 with the optimal conditions, 0.02 g baicalin, and the conversion rate was 68%, 97.3%, 97.31% respectively. The results of the study provided a guarantee for the transformation of baicalin.


Assuntos
beta-Glucosidase/metabolismo , Flavonoides , Concentração de Íons de Hidrogênio
10.
Biotechnol Lett ; 39(8): 1219-1227, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28503710

RESUMO

OBJECTIVE: To engineer Pichia pastoris for heterologous production of cellulase from Musca domestica and explore its potential for industrial applications. RESULTS: A new beta-glucosidase gene (bg), encoding 562 amino acids, was cloned from M. domestica by using rapid amplification of cDNA ends. The gene bg was linked to pPICZαA and expressed in P. pastoris with a yield of 500 mg l-1. The enzyme has the maximum activity with 27.6 U mg-1 towards cellulose. The beta-glucosidase has stable activity from 20 to 70 °C and can tolerate one-mole glucose. It has the maximum activities for salicin (25.9 ± 1.8 U mg-1), cellobiose (40.1 ± 2.3 U mg-1) and cellulose (27.6 ± 3.5 U mg-1). The wide-range substrate activities of the beta-glucosidase were further verified by matrix-assisted laser desorption/ionization mass spectra. Structural analysis shows that the beta-glucosidase belongs to glycoside hydrolase family Ι and possesses O-glycosylation sites. CONCLUSIONS: Thus, a multifunctional beta-glucosidase was expressed from M. domestica and provides a potential tool for industrial application of cellulose.


Assuntos
Moscas Domésticas/enzimologia , Proteínas de Insetos/metabolismo , Proteínas Recombinantes/metabolismo , beta-Glucosidase/metabolismo , Animais , Glucose/metabolismo , Moscas Domésticas/genética , Hidrólise , Proteínas de Insetos/química , Proteínas de Insetos/genética , Cinética , Filogenia , Pichia/genética , Estabilidade Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , beta-Glucosidase/química , beta-Glucosidase/genética
11.
Appl Microbiol Biotechnol ; 100(13): 5781-9, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26830100

RESUMO

We engineered efficient 2,3-butanediol (23BD) production from cellobiose using Bacillus subtilis. First, we found that B. subtilis harboring an empty vector could produce 23BD from cellobiose. However, productivity using cellobiose as a carbon source was lower than that when using glucose. This lower productivity was improved by adding purified beta-glucosidase from Thermobifida fusca YX (Tfu_0937) in the fermentation. Encouraged by these findings, we found that hydrolysis of cellobiose to glucose was an important reaction of 23BD biosynthesis in B. subtilis using cellobiose. Hence, we created efficient 23BD production from cellobiose using exogenous Tfu_0937-expressing B. subtilis. Using the engineered strain, 21.2 g L(-1) of 23BD was produced after 72 h of cultivation. The productivity and yield were 0.294 g L(-1) h(-1) and 0.35 g 23BD/g cellobiose, respectively. We successfully demonstrated efficient 23BD production from cellobiose by using BGL-expressing B. subtilis.


Assuntos
Actinobacteria/enzimologia , Bacillus subtilis/metabolismo , Proteínas de Bactérias/genética , Butileno Glicóis/metabolismo , Celobiose/metabolismo , beta-Glucosidase/genética , Actinobacteria/genética , Bacillus subtilis/genética , Proteínas de Bactérias/metabolismo , Fermentação , Glucose/metabolismo , Engenharia Metabólica , beta-Glucosidase/metabolismo
12.
Eur J Pediatr ; 175(7): 931-41, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27118558

RESUMO

UNLABELLED: We aimed to establish the utility of serum cytosolic ß-glycosidase (CBG) assay as a NEC diagnosis tool. CBG activity has been compared in 192 NEC-free (NEC(-)) and 13 NEC-affected (NEC(+)) neonates, with modified Bell's stages II/III, born at Reina Sofia University Hospital; additional blood hematology, microbiology, and biochemical parameters have been assayed. NEC(+) neonates have higher serum CBG activity, 26.4 ± 12.4 mU/mg; 95 % CI (18.8-33.9), than NEC(-) infants, 11.0 ± 6.6 mU/mg; 95 % CI (10.1-11.9) (p < 0.0001). The CBG cutoff value in the ROC curve, 15.6 mU/mg, discriminates NEC(+)/NEC(-) infants with 84.6 % sensitivity, 85.9 % specificity, 37.9 positive predictive value and 98.2 negative predictive value, 6.11 positive likelihood ratio and 0.18 negative likelihood ratio, 33.61 DOR, and 0.89 AUC. A combined panel [CBG + aspartate aminotransferase + C-reactive protein] shows a 0.90 AUC value in multiple linear regressions. CONCLUSIONS: The serum CBG level is a good NEC diagnosis test and a novel NEC biomarker which may become a screening tool. WHAT IS KNOWN: •NEC affects ∼2.5 % of infants at NICU, ∼90 % of them weighing <1500 g. •NEC requires a careful differential diagnosis, being lethal if not diagnosed and treated. What is new: •CBG assay will be useful to determine infants without NEC and preventing unnecessary treatment. •CBG assay could discriminate NEC better than other gut-specific sera protein biomarkers.


Assuntos
Enterocolite Necrosante/diagnóstico , beta-Glucosidase/sangue , Biomarcadores/sangue , Ensaios Enzimáticos Clínicos , Enterocolite Necrosante/sangue , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Recém-Nascido de muito Baixo Peso , Unidades de Terapia Intensiva Neonatal , Modelos Logísticos , Masculino , Valor Preditivo dos Testes , Estudos Prospectivos , Curva ROC , Sensibilidade e Especificidade
13.
Biosci Biotechnol Biochem ; 80(1): 89-94, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26168358

RESUMO

Isoflavones play important roles in plant-microbe interactions in rhizospheres. Soybean roots secrete daidzein and genistein to attract rhizobia. Despite the importance of isoflavones in plant-microbe interactions, little is known about the developmental and nutritional regulation of isoflavone secretion from soybean roots. In this study, soybeans were grown in hydroponic culture, and isoflavone contents in tissues, isoflavone secretion from the roots, and the expression of isoflavone conjugates hydrolyzing beta-glucosidase (ICHG) were investigated. Isoflavone contents did not show strong growth-dependent changes, while secretion of daidzein from the roots dramatically changed, with higher secretion during vegetative stages. Coordinately, the expression of ICHG also peaked at vegetative stages. Nitrogen deficiency resulted in 8- and 15-fold increases in secretion of daidzein and genistein, respectively, with no induction of ICHG. Taken together, these results suggest that large amounts of isoflavones were secreted during vegetative stages via the hydrolysis of (malonyl)glucosides with ICHG.


Assuntos
Genisteína/metabolismo , Glycine max/metabolismo , Inibidores do Crescimento/metabolismo , Isoflavonas/metabolismo , Proteínas de Plantas/genética , Raízes de Plantas/metabolismo , beta-Glucosidase/genética , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Inibidores do Crescimento/biossíntese , Hidrólise , Hidroponia , Isoflavonas/biossíntese , Nitrogênio/deficiência , Nitrogênio/farmacologia , Proteínas de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/microbiologia , Rhizobiaceae/fisiologia , Rizosfera , Glycine max/efeitos dos fármacos , Glycine max/genética , Glycine max/microbiologia , Simbiose/fisiologia , beta-Glucosidase/metabolismo
14.
J Biol Chem ; 289(45): 31624-37, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25164811

RESUMO

Cellulase mixtures from Hypocrea jecorina are commonly used for the saccharification of cellulose in biotechnical applications. The most abundant ß-glucosidase in the mesophilic fungus Hypocrea jecorina is HjCel3A, which hydrolyzes the ß-linkage between two adjacent molecules in dimers and short oligomers of glucose. It has been shown that enhanced levels of HjCel3A in H. jecorina cellulase mixtures benefit the conversion of cellulose to glucose. Biochemical characterization of HjCel3A shows that the enzyme efficiently hydrolyzes (1,4)- as well as (1,2)-, (1,3)-, and (1,6)-ß-D-linked disaccharides. For crystallization studies, HjCel3A was produced in both H. jecorina (HjCel3A) and Pichia pastoris (Pp-HjCel3A). Whereas the thermostabilities of HjCel3A and Pp-HjCel3A are the same, Pp-HjCel3A has a higher degree of N-linked glycosylation. Here, we present x-ray structures of HjCel3A with and without glucose bound in the active site. The structures have a three-domain architecture as observed previously for other glycoside hydrolase family 3 ß-glucosidases. Both production hosts resulted in HjCel3A structures that have N-linked glycosylations at Asn(208) and Asn(310). In H. jecorina-produced HjCel3A, a single N-acetylglucosamine is present at both sites, whereas in Pp-HjCel3A, the P. pastoris-produced HjCel3A enzyme, the glycan chains consist of 8 or 4 saccharides. The glycosylations are involved in intermolecular contacts in the structures derived from either host. Due to the different sizes of the glycosylations, the interactions result in different crystal forms for the two protein forms.


Assuntos
Proteínas Fúngicas/química , Glucosidases/química , Hypocrea/enzimologia , beta-Glucosidase/química , Biomassa , Domínio Catalítico , Celulase/química , Cristalografia por Raios X , Glucose/química , Glucosídeos/química , Glicosilação , Ligação de Hidrogênio , Hidrólise , Ligantes , Espectrometria de Massas , Nitrobenzenos/química , Oligossacarídeos/química , Pichia/metabolismo , Especificidade por Substrato , Temperatura , Xilose/análogos & derivados , Xilose/química
15.
J Biol Chem ; 288(25): 18325-34, 2013 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-23661705

RESUMO

The ß-glucosidase encoded by the td2f2 gene was isolated from a compost microbial metagenomic library by functional screening. The protein was identified to be a member of the glycoside hydrolase family 1 and was overexpressed in Escherichia coli, purified, and biochemically characterized. The recombinant ß-glucosidase, Td2F2, exhibited enzymatic activity with ß-glycosidic substrates, with preferences for glucose, fucose, and galactose. Hydrolysis occurred at the nonreducing end and in an exo manner. The order of catalytic efficiency for glucodisaccharides and cellooligosaccharides was sophorose > cellotetraose > cellotriose > laminaribiose > cellobiose > cellopentaose > gentiobiose, respectively. Intriguingly, the p-nitrophenyl-ß-D-glucopyranoside hydrolysis activity of Td2F2 was activated by various monosaccharides and sugar alcohols. At a D-glucose concentration of 1000 mM, enzyme activity was 6.7-fold higher than that observed in the absence of D-glucose. With 31.3 mM D-glucose, Td2F2 catalyzed transglycosylation to generate sophorose, laminaribiose, cellobiose, and gentiobiose. Transglycosylation products were detected under all activated conditions, suggesting that the activity enhancement induced by monosaccharides and sugar alcohols may be due to the transglycosylation activity of the enzyme. These results show that Td2F2 obtained from a compost microbial metagenome may be a potent candidate for industrial applications.


Assuntos
Biblioteca Genômica , Metagenoma/genética , Microbiologia do Solo , beta-Glucosidase/genética , Sequência de Aminoácidos , Biocatálise/efeitos dos fármacos , Celobiose/metabolismo , Dissacarídeos/metabolismo , Fucose/metabolismo , Galactose/metabolismo , Glucanos/metabolismo , Glucose/metabolismo , Glicosídeos/metabolismo , Glicosilação , Concentração de Íons de Hidrogênio , Cinética , Dados de Sequência Molecular , Monossacarídeos/farmacologia , Homologia de Sequência de Aminoácidos , Especificidade por Substrato , Álcoois Açúcares/farmacologia , Temperatura , beta-Glucosidase/metabolismo
16.
J Fungi (Basel) ; 10(6)2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38921393

RESUMO

Trichoderma erinaceum is a filamentous fungus that was isolated from decaying sugarcane straw at a Brazilian ethanol biorefinery. This fungus shows potential as a source of plant cell wall-degrading enzymes (PCWDEs). In this study, we conducted a comprehensive multiomics investigation of T. erinaceum to gain insights into its enzymatic capabilities and genetic makeup. Firstly, we performed genome sequencing and assembly, which resulted in the identification of 10,942 genes in the T. erinaceum genome. We then conducted transcriptomics and secretome analyses to map the gene expression patterns and identify the enzymes produced by T. erinaceum in the presence of different substrates such as glucose, microcrystalline cellulose, pretreated sugarcane straw, and pretreated energy cane bagasse. Our analyses revealed that T. erinaceum highly expresses genes directly related to lignocellulose degradation when grown on pretreated energy cane and sugarcane substrates. Furthermore, our secretome analysis identified 35 carbohydrate-active enzymes, primarily PCWDEs. To further explore the enzymatic capabilities of T. erinaceum, we selected a ß-glucosidase from the secretome data for recombinant production in a fungal strain. The recombinant enzyme demonstrated superior performance in degrading cellobiose and laminaribiose compared to a well-known enzyme derived from Trichoderma reesei. Overall, this comprehensive study provides valuable insights into both the genetic patterns of T. erinaceum and its potential for lignocellulose degradation and enzyme production. The obtained genomic data can serve as an important resource for future genetic engineering efforts aimed at optimizing enzyme production from this fungus.

17.
Sci Rep ; 14(1): 10012, 2024 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-38693138

RESUMO

Beta-glucosidases catalyze the hydrolysis of the glycosidic bonds of cellobiose, producing glucose, which is a rate-limiting step in cellulose biomass degradation. In industrial processes, ß-glucosidases that are tolerant to glucose and stable under harsh industrial reaction conditions are required for efficient cellulose hydrolysis. In this study, we report the molecular cloning, Escherichia coli expression, and functional characterization of a ß-glucosidase from the gene, CelGH3_f17, identified from metagenomics libraries of an Ethiopian soda lake. The CelGH3_f17 gene sequence contains a glycoside hydrolase family 3 catalytic domain (GH3). The heterologous expressed and purified enzyme exhibited optimal activity at 50 °C and pH 8.5. In addition, supplementation of 1 M salt and 300 mM glucose enhanced the ß-glucosidase activity. Most of the metal ions and organic solvents tested did not affect the ß-glucosidase activity. However, Cu2+ and Mn2+ ions, Mercaptoethanol and Triton X-100 reduce the activity of the enzyme. The studied ß-glucosidase enzyme has multiple industrially desirable properties including thermostability, and alkaline, salt, and glucose tolerance.


Assuntos
Biomassa , Lagos , beta-Glucosidase , beta-Glucosidase/genética , beta-Glucosidase/metabolismo , beta-Glucosidase/química , Lagos/microbiologia , Metagenômica/métodos , Escherichia coli/genética , Escherichia coli/metabolismo , Metagenoma , Clonagem Molecular , Estabilidade Enzimática , Hidrólise , Concentração de Íons de Hidrogênio , Celulose/metabolismo , Temperatura , Glucose/metabolismo
18.
EFSA J ; 22(10): e9040, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39376691

RESUMO

The food enzyme ß-glucosidase (ß-d-glucoside glucohydrolase, EC 3.2.1.21) is produced with the non-genetically modified Penicillium guanacastense strain AE-GLY by Amano Enzyme Inc. A safety evaluation of this food enzyme was made previously, in which EFSA concluded that this food enzyme did not give rise to safety concerns when used in four food manufacturing processes. Subsequently, the applicant has requested to extend its use to include three additional processes and to revise the use levels. In this assessment, EFSA updated the safety evaluation of this food enzyme when used in a total of seven food manufacturing processes. The dietary exposure was calculated to be up to 0.206 mg total organic solids (TOS)/kg body weight (bw) per day in European populations. Using the no observed adverse effect level reported in the previous opinion (943 mg TOS/kg bw per day), the Panel derived a margin of exposure of at least 4578. Based on the previous evaluation, the assessment of the new data and the revised margin of exposure, the Panel concluded that this food enzyme does not give rise to safety concerns under the revised intended conditions of use.

19.
EFSA J ; 22(7): e8872, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38966133

RESUMO

The food enzyme ß-glucosidase (ß-D-glucoside glucohydrolase; EC 3.2.1.21) is produced with the non-genetically modified Penicillium guanacastense strain AE-GLY by Amano Enzyme Inc. The food enzyme is intended to be used in four food manufacturing processes. Dietary exposure to the food enzyme-total organic solids (TOS) was estimated to be up to 4.054 mg TOS/kg body weight (bw) per day in European populations. Genotoxicity tests did not raise a safety concern. The systemic toxicity was assessed by means of a repeated dose 90-day oral toxicity study in rats. The Panel identified a no observed adverse effect level of 943 mg TOS/kg bw per day, the highest dose tested, which when compared with the estimated dietary exposure, resulted in a margin of exposure of at least 233. A search for the similarity of the amino acid sequence of the food enzyme to known allergens was made and no match was found. The Panel considered that the risk of allergic reactions by dietary exposure cannot be excluded, but the likelihood is low. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use.

20.
J Oral Biol Craniofac Res ; 13(2): 155-163, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36618007

RESUMO

Background: Amygdalin is known as a chemical compound derived from various fruits. The glycosides existing in this plant have been historically utilized as an anticancer agent. This review presented an overview of amygdalin and its onco-immunity and other therapeutic medical applications. Method: A literature search for studies relating to amygdalin and cancer treatment was carried out using PubMed and Google Scholar. Combinations of the following terms were used in the search strategies: "amygdalin," "rhodanese," "cyanide," "cyanogenic," "hypothiocyanite," "mandelonitrile," "glucosides," "cancer," "apoptosis," and "cytotoxicity," combined with a cancer term such as "seed," "almond," or "apricot," "cancer + cell line, antiproliferation or inhibition," "BAX From the March 3, 1981 until the April 15, 2021, all of the English-language papers were evaluated based on the inclusion criteria. Publications included reviews, chapters from books, and original research papers. Results: The FDA prohibits Amygdalin from medical usage as an anticancer treatment due to a lack of proof of cure in cancer cases. When this natural-based compound is used with conditional chemotherapeutic medicines causes synergistic effects. Besides, amygdalin is used to manage asthma, improve the immune system, induce apoptosis in human renal fibroblasts, and inhibit hyperglycemia. Conclusion: Various medical uses of amygdalin have been found such as managing asthma, improving the immune system, inducing apoptosis in human renal fibroblasts, and inhibiting hyperglycemia. More effective in vitro and review studies are required to elucidate the exact role of this herb in medical applications.

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