RESUMO
ß-Glucosidase is a crucial cellulase, as its activity determines the efficiency of cellulose hydrolysis into glucose. This study addresses the functional and structural characteristics of Thermotoga profunda ß-glucosidase (Tp-BGL). Tp-BGL exhibited a Km of 0.3798 mM for p-nitrophenyl-ß-d-glucopyranoside (pNPGlc) and 4.44 mM for cellobiose, with kcat/Km of 1211.16 and 4.18 s-1 mM-1, respectively. In addition, Tp-BGL showed significant pH adaptability and thermal stability, with a Tm of 85.7 °C and retaining >90 % of its activity after incubation at 80 °C for 90 min. The crystal structure of Tp-BGL was resolved at 1.95 Å resolution, and reveals a typical TIM barrel structure. Comparative structural analysis highlighted that the major distinction between Tp-BGL and the other glucosidases lies in their loop regions.
Assuntos
Modelos Moleculares , Thermotoga , beta-Glucosidase , beta-Glucosidase/química , beta-Glucosidase/metabolismo , Cristalografia por Raios X , Thermotoga/enzimologia , Thermotoga/química , Thermotoga/metabolismo , Estabilidade Enzimática , Conformação Proteica , Concentração de Íons de Hidrogênio , Cinética , Especificidade por Substrato , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genéticaRESUMO
ß-glucosidases (Bgls) are glycosyl hydrolases that catalyze the conversion of cellobiose or glucosyl-polysaccharide into glucose. Bgls are widely used in industry to produce bioethanol, wine and juice, and feed. Tris (tris(hydroxymethyl)aminomethane) is an organic compound that can inhibit the hydrolase activity of some Bgls, but the inhibition state and selectivity have not been fully elucidated. Here, three crystal structures of Thermoanaerobacterium saccharolyticum Bgl complexed with the Tris molecule were determined at 1.55-1.95 Å. The configuration of Tris binding to TsaBgl remained consistent across three crystal structures, and the amino acids interacting with the Tris molecule were conserved across Bgl enzymes. The positions O1 and O3 atoms of Tris exhibit the same binding moiety as the hydroxyl group of the glucose molecule. Tris molecules are stably positioned at the glycone site and coordinate with surrounding water molecules. The Tris-binding configuration of TsaBgl is similar to that of HjeBgl, HgaBgl, ManBgl, and KflBgl, but the arrangement of the water molecule coordinating Tris at the aglycone site differs. Meanwhile, both the arrangement of Tris and the water molecules in ubBgl, NkoBgl, and SfrBgl differ from those in TsaBgl. The binding configuration and affinity of the Tris molecule for Bgl may be affected by the residues on the aglycone and gatekeeper regions. This result will extend our knowledge of the inhibitory effect of Tris molecules on TsaBgl.
Assuntos
Celobiose , beta-Glucosidase , beta-Glucosidase/metabolismo , Celobiose/metabolismo , Glucose/metabolismo , Catálise , ÁguaRESUMO
Cello-oligosaccharides (COS) become a new type of functional oligosaccharides. COS transglycosylation reactions were studied to enhance COS yield production. Seeking the ability of the free form of Fusarium solani ß-glucosidase (FBgl1) to synthesize COS under low substrate concentrations, we found out that this biocatalyst initiates this reaction with only 1 g/L of cellobiose, giving rise to the formation of cellotriose. Cellotriose and cellopentaose were detected in biphasic conditions with an immobilized FBgl1 and when increased to 50 g/L of cellobiose as a starter concentration. After the biocatalyst recycling process, the trans-glycosylation yield of COS was maintained after 5 cycles, and the COS concentration was 6.70 ± 0.35 g/L. The crude COS contained 20.15 ± 0.25 g/L glucose, 23.15 ± 0.22 g/L non-reacting substrate cellobiose, 5.25 ± 0.53 g/L, cellotriose and 1.49 ± 0.32 g/L cellopentaose. A bioprocess was developed for cellotriose enrichment, using whole Bacillus velezensis cells as a microbial purification tool. This bacteria consumed glucose, unreacted cellobiose, and cellopentaose while preserving cellotriose in the fermented medium. This study provides an excellent enzyme candidate for industrial COS production and is also the first study on the single-step COS enrichment process.
Assuntos
Bacillus , Celobiose , Fusarium , Oligossacarídeos , beta-Glucosidase , Fusarium/enzimologia , Fusarium/metabolismo , Fusarium/genética , beta-Glucosidase/metabolismo , Oligossacarídeos/metabolismo , Celobiose/metabolismo , Bacillus/enzimologia , Bacillus/metabolismo , Bacillus/genética , Prebióticos , Glicosilação , Glucose/metabolismoRESUMO
Minor ginsenosides produced by ß-glucosidase are interesting biologically and pharmacologically. In this study, new ginsenoside-hydrolyzing glycosidase from Furfurilactobacillus rossiae DCYL3 was cloned and expressed in Escherichia coli strain BL21. The enzyme converted Rb1 and Gyp XVII into Rd and compound K following the pathways: Rb1âRd and Gyp XVIIâF2âCK, respectively at optimal condition: 40 °C, 15 min, and pH 6.0. Furthermore, we examined the cytotoxicity, NO production, ROS generation, and gene expression of Gynostemma extract (GE) and bioconverted Gynostemma extract (BGE) in vitro against A549 cell lines for human lung cancer and macrophage RAW 264.7 cells for antiinflammation, respectively. As a result, BGE demonstrated significantly greater toxicity than GE against lung cancer at a dose of 500 µg/mL but in normal cells showed lower toxicity. Then, we indicated an enhanced generation of ROS, which may be boosting cancer cell toxicity. By blocking the intrinsic way, BGE increased p53, Bax, Caspase 3, 9, and while Bcl2 is decreased. At 500 µg/mL, the BGE sample was less toxic in normal cells and decreased the LPS-treated NO and ROS level to reduce inflammation. In addition, BGE inhibited the expression of pro-inflammatory genes COX-2, iNOS, IL-6, and IL-8 in RAW 264.7 cells than the sample of GE. In conclusion, FrBGL3 has considerable downstream applications for high-yield, low-cost, effective manufacture of minor ginsenosides. Moreover, the study's findings imply that BGE would be potential materials for anti-cancer and anti-inflammatory agent after consideration of future studies.
â¢The first time ß-glucosidase (FrBGL3) from Furfurilactobacillus rossiae was identified and characterized.â¢FrBGL3 activity in ginsenoside and gypenoside bioconversion were found and confirmed.â¢Application in Gynostemma extract bioconversion by FrBGL3 boosts anti-inflammatory and anti-cancer activities.
Assuntos
beta-Glucosidase , Camundongos , Animais , Humanos , Células RAW 264.7 , Células A549 , beta-Glucosidase/genética , beta-Glucosidase/metabolismo , beta-Glucosidase/química , Clonagem Molecular , Ginsenosídeos/metabolismo , Ginsenosídeos/farmacologia , Escherichia coli/genética , Escherichia coli/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Macrófagos/efeitos dos fármacos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Óxido Nítrico/metabolismo , Clostridiales/genética , Clostridiales/enzimologia , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/metabolismoRESUMO
The present study focuses on investigating 60 strains of yeast isolated from the natural fermentation broth of Vitis labruscana Baily × Vitis vinifera L. These strains underwent screening using lysine culture medium and esculin culture medium, resulting in the identification of 27 local non-Saccharomyces yeast strains exhibiting high ß-glucosidase production. Subsequent analysis of their fermentation characteristics led to the selection of four superior strains (Z-6, Z-11, Z-25, and Z-58) with excellent ß-glucosidase production and fermentation performance. Notably, these selected strains displayed a dark coloration on esculin medium and exhibited robust gas production during Duchenne tubules' fermentation test. Furthermore, all four non-Saccharomyces yeast strains demonstrated normal growth under specific conditions including SO2 mass concentration ranging from 0.1 to 0.3 g/L, temperature between 25 and 30 °C, glucose mass concentration ranging from 200 to 400 g/L, and ethanol concentration at approximately 4%. Molecular biology identification confirmed that all selected strains belonged to Pichia kudriavzevii species which holds great potential for wine production.
Assuntos
Vitis , Vinho , Saccharomyces cerevisiae/metabolismo , Fermentação , beta-Glucosidase/metabolismo , Esculina/análise , Leveduras/metabolismo , Vinho/análise , Pichia/metabolismoRESUMO
A Gram-stain-positive actinomycete, designated REN17T, was isolated from fermented grains of Baijiu collected from Sichuan, PR China. It exhibited branched substrate mycelia and a sparse aerial mycelium. The optimal growth conditions for REN17T were determined to be 28â°C and pH 7, with a NaCl concentration of 0â% (w/v). ll-Diaminopimelic acid was the diagnostic amino acid of the cell-wall peptidoglycan and the polar lipids were composed of phosphatidylethanolamine, phosphatidylinositol, an unidentified phospholipid, two unidentified lipids and four unidentified glycolipids. The predominant menaquinone was MK-9 (H2), MK-9 (H4), MK-9 (H6) and MK-9 (H8). The major fatty acids were iso-C16 : 0. The 16S rRNA sequence of REN17T was most closely related to those of Streptomyces apricus SUN 51T (99.8â%), Streptomyces liliiviolaceus BH-SS-21T (99.6â%) and Streptomyces umbirnus JCM 4521T (98.9â%). The digital DNA-DNA hybridization, average nucleotide identity and average amino acid identify values between REN17T and its closest replated strain, of S. apricus SUN 51T, were 35.9, 88.9 and 87.3â%, respectively. Therefore, REN17T represents a novel species within the genus Streptomyces, for which the name Streptomyces beigongshangae sp. nov. is proposed. The type strain is REN17T (=GDMCC 4.193T=JCM 34712T). While exploring the function of the strain, REN17T was found to possess the ability to transform major ginsenosides of Panax notoginseng (Burk.) F.H. Chen (Araliaceae) into minor ginsenoside through HPLC separation, which was due to the presence of ß-glucosidase. The recombinant ß-glucosidase was constructed and purified, which could produce minor ginsenosides of Rg3 and C-K. Finally, the enzymatic properties were characterized.
Assuntos
Técnicas de Tipagem Bacteriana , DNA Bacteriano , Ácidos Graxos , Fermentação , Ginsenosídeos , Hibridização de Ácido Nucleico , Panax notoginseng , Filogenia , RNA Ribossômico 16S , Análise de Sequência de DNA , Streptomyces , Vitamina K 2 , RNA Ribossômico 16S/genética , Ácidos Graxos/química , Streptomyces/isolamento & purificação , Streptomyces/genética , Streptomyces/classificação , Vitamina K 2/análogos & derivados , DNA Bacteriano/genética , China , Panax notoginseng/microbiologia , Ginsenosídeos/metabolismo , Peptidoglicano , Grão Comestível/microbiologia , Ácido Diaminopimélico , Fosfolipídeos/química , Composição de BasesRESUMO
This study reports a thermostable glucose-stimulated ß-glucosidase, BglY442, from hot-spring metagenomic data that was cloned and expressed in Escherichia coli BL21 (DE3). The molecular mass of recombinant BglY442 was 69.9 kDa and was used in the production of gardenia blue. The recombinant BglY442 showed its maximum activity at pH 6.0 and 75 °C, maintained 50 % activity at 70 °C for 36 h, presented over 90 % activity in a broad pH range and a wide range of pH stability. Moreover, BglY442 exhibited excellent tolerance toward methanol and ethanol. The specific activity of BglY442 was 235 U/mg at pH 6.0 and 75 °C with 10 mM pNPG as substrate. BglY442 activity increased by over fourfold with 2 M glucose or xylose. Specifically, the enzyme kinetics of BglY442 seem to be non-Michaelis-Menten kinetics or atypical kinetics because the Michaelis-Menten saturation kinetics were not observed with pNPG, oNPG or geniposide as substrates. Under optimum conditions, geniposide was dehydrated by BglY442 and reacted with nine amino acids respectively by the one-pot method. Only the Arg or Met derived pigments showed bright blue, and these two pigments had similar ultraviolet absorption spectra. The OD590 nm of GB was detected to be 1.06 after 24 h with the addition of Arg and 1.61 after 36 h with the addition of Met. The intermediate was elucidated and identified as ginipin. Molecular docking analysis indicated that the enzyme had a similar catalytic mechanism to the reported GH1 Bgls. BglY442 exhibited potential for gardenia blue production by the one-pot method. With outstanding thermostability and glucose tolerance, BglY442 should be considered a potential ß-glucosidase in biotechnology applications.
Assuntos
Gardenia , Glucose , Iridoides , Glucose/farmacologia , Proteínas Recombinantes/metabolismo , beta-Glucosidase/metabolismo , Metagenoma , Simulação de Acoplamento Molecular , Concentração de Íons de Hidrogênio , Estabilidade Enzimática , Especificidade por Substrato , Temperatura , CinéticaRESUMO
The soil environment for straw return is a rich and valuable library containing many microorganisms and proteins. In this study, we aimed to screen a high-quality ß-glucosidase (BGL) from the soil metagenomic library and to overcome the limitation of the low extraction rate of resveratrol in Polygonum cuspidatum. This includes the construction of a soil metagenomic library, screening of BGL, bioinformatics analysis, cloning, expression, immobilization, enzymatic property analysis, and application for the transformation of polydatin. The results showed that the soil metagenomic library of straw return was successfully constructed, and a novel BGL was screened. The identified 1356 bp long BGL belonged to the glycoside hydrolase 1 (GH1) family and was named Bgl1356. After successful cloning and expression of Bgl1356, it was immobilized using chitosan. The optimum temperature of immobilized Bgl1356 was 50 °C, and the pH was 5. It exhibited good tolerance for various metal ions (CO2+, Ni2+, Cu2+, Mn2+, Na2+, Ca2+, and Ag+) and organic solvents (DMSO, Triton-X-10, and ethanol). Enzymatic kinetics assays showed that Bgl1356 had good affinity for the substrate, and the specific enzyme activity was 234.03 U/mg. The conversion rate of polydatin by immobilized Bgl1356 was 95.70 ± 1.08%, facilitating the production of high amounts of resveratrol. Thus, this paper reports a novel temperature-, organic solvent-, and metal ion-tolerant BGL that has good application prospects in the pharmaceutical industry.
Assuntos
Glucosídeos , Metagenoma , Estilbenos , beta-Glucosidase , Resveratrol , beta-Glucosidase/genética , beta-Glucosidase/química , beta-Glucosidase/metabolismo , Temperatura , Metais , Clonagem Molecular , Concentração de Íons de HidrogênioRESUMO
In this study, we conducted a comprehensive investigation into a GH3 family ß-glucosidase (BGL) from the wild-type strain of Oenococcus oeni and its mutated counterpart from the acid-tolerant mutant strain. Our analysis revealed the mutant BGL's remarkable capacity to adapt to wine-related stress conditions, including heightened tolerance to low pH, elevated ethanol concentrations, and metal ions. Additionally, the mutant BGL exhibited superior hydrolytic activity towards various substrates. Through de novo modeling, we identified specific amino acid mutations responsible for its resilience to low pH and high ethanol environments. In simulated wine conditions, the mutant BGL outperformed both wild-type and commercial BGLs, efficiently releasing terpene and phenolic aglycones from glycosides in wine grapes. These findings not only expand our understanding of O. oeni BGLs but also highlight their potential in enhancing wine production. The mutant BGL's enhanced adaptation to wine stress conditions opens promising avenue for improving wine quality and flavor.
Assuntos
Oenococcus , Vinho , Vinho/análise , beta-Glucosidase/genética , beta-Glucosidase/metabolismo , Odorantes/análise , Etanol/metabolismo , Oenococcus/genética , Oenococcus/metabolismo , FermentaçãoRESUMO
The present study reports a highly thermostable ß-glucosidase (GH3) from Rasamsonia emersonii that was heterologously expressed in Pichia pastoris. Extracellular ß-glucosidase was purified to homogeneity using single step affinity chromatography with molecular weight of ~ 110 kDa. Intriguingly, the purified enzyme displayed high tolerance to inhibitors mainly acetic acid, formic acid, ferulic acid, vanillin and 5-hydroxymethyl furfural at concentrations exceeding those present in acid steam pretreated rice straw slurry used for hydrolysis and subsequent fermentation in 2G ethanol plants. Characteristics of purified ß-glucosidase revealed the optimal activity at 80 °C, pH 5.0 and displayed high thermostability over broad range of temperature 50-70 °C with maximum half-life of ~ 60 h at 50 °C, pH 5.0. The putative transglycosylation activity of ß-glucosidase was appreciably enhanced in the presence of methanol as an acceptor. Using the transglycosylation ability of ß-glucosidase, the generated low cost mixed glucose disaccharides resulted in the increased induction of R. emersonii cellulase under submerged fermentation. Scaling up the recombinant protein production at fermenter level using temporal feeding approach resulted in maximal ß-glucosidase titres of 134,660 units/L. Furthermore, a developed custom made enzyme cocktail consisting of cellulase from R. emersonii mutant M36 supplemented with recombinant ß-glucosidase resulted in significantly enhanced hydrolysis of pretreated rice straw slurry from IOCL industries (India). Our results suggest multi-faceted ß-glucosidase from R. emersonii can overcome obstacles mainly high cost associated enzyme production, inhibitors that impair the sugar yields and thermal inactivation of enzyme.
Assuntos
Eurotiales , beta-Glucosidase , Hidrólise , beta-Glucosidase/química , BiomassaRESUMO
The formation and analysis of amyloid fibers by two ß-glucosidases, BglA and BglB, belonging to the GH1 enzyme family, are reported. Both proteins have the (ß/α)8 TIM-barrel fold, which is characteristic of this family and is also the most common protein structure. BglA is an octamer, whereas BglB is a monomer. Amyloid fibrillation using pH and temperature as perturbing agents was investigated using fluorescence spectroscopy as a preliminary approach and corroborated using wide-field optical microscopy, confocal microscopy, and field-emission scanning electron microscopy. These analyses showed that both enzymes fibrillate at a wide range of acidic and alkaline conditions and at several temperature conditions, particularly at acidic pH (3-4) and at temperatures between 45 and 65 °C. Circular dichroism spectroscopy corroborated the transition from an α-helix to a ß-sheet secondary structure of both proteins in conditions where fibrillation was observed. Overall, our results suggest that fibrillation is a rather common phenomenon caused by protein misfolding, driven by a transition from an α-helix to a ß-sheet secondary structure, that many proteins can undergo if subjected to conditions that disturb their native conformation.
Assuntos
Amiloide , Amiloide/química , Amiloide/metabolismo , Concentração de Íons de Hidrogênio , Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/metabolismo , Dicroísmo Circular , Temperatura , Estrutura Secundária de Proteína , Dobramento de ProteínaRESUMO
Abscisic acid (ABA) plays a crucial role in plant defense mechanisms under adverse environmental conditions, but its metabolism and perception in response to heavy metals are largely unknown. In Pisum sativum exposed to CdCl2, an accumulation of free ABA was detected in leaves at different developmental stages (A, youngest, unexpanded; B1, youngest, fully expanded; B2, mature; C, old), with the highest content found in A and B1 leaves. In turn, the content of ABA conjugates, which was highest in B2 and C leaves under control conditions, increased only in A leaves and decreased in leaves of later developmental stages after Cd treatment. Based on the expression of PsNCED2, PsNCED3 (9-cis-epoxycarotenoid dioxygenase), PsAO3 (aldehyde oxidase) and PsABAUGT1 (ABA-UDP-glucosyltransferase), and the activity of PsAOγ, B2 and C leaves were found to be the main sites of Cd-induced de novo synthesis of ABA from carotenoids and ABA conjugation with glucose. In turn, ß-glucosidase activity and the expression of genes encoding ABA receptors (PsPYL2, PsPYL4, PsPYL8, PsPYL9) suggest that in A and B1 leaves, Cd-induced release of ABA from inactive ABA-glucosyl esters and enhanced ABA perception comes to the forefront when dealing with Cd toxicity. The distinct role of leaves at different developmental stages in defense against the harmful effects of Cd is discussed.
Assuntos
Ácido Abscísico , Cádmio , Regulação da Expressão Gênica de Plantas , Pisum sativum , Folhas de Planta , Proteínas de Plantas , Ácido Abscísico/metabolismo , Pisum sativum/metabolismo , Pisum sativum/efeitos dos fármacos , Pisum sativum/genética , Folhas de Planta/metabolismo , Folhas de Planta/efeitos dos fármacos , Cádmio/metabolismo , Cádmio/toxicidade , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Dioxigenases/metabolismo , Dioxigenases/genética , beta-Glucosidase/metabolismo , beta-Glucosidase/genéticaRESUMO
As a crucial enzyme for cellulose degradation, ß-glucosidase finds extensive applications in food, feed, and bioethanol production; however, its potential is often limited by inadequate thermal stability and glucose tolerance. In this study, a functional gene (lq-bg5) for a GH1 family ß-glucosidase was obtained from the metagenomic DNA of a hot spring sediment sample and heterologously expressed in E. coli and the recombinant enzyme was purified and characterized. The optimal temperature and pH of LQ-BG5 were 55 °C and 4.6, respectively. The relative residual activity of LQ-BG5 exceeded 90% at 55 °C for 9 h and 60 °C for 6 h and remained above 100% after incubation at pH 5.0-10.0 for 12 h. More importantly, LQ-BG5 demonstrated exceptional glucose tolerance with more than 40% activity remaining even at high glucose concentrations of 3000 mM. Thus, LQ-BG5 represents a thermophilic ß-glucosidase exhibiting excellent thermal stability and remarkable glucose tolerance, making it highly promising for lignocellulose development and utilization.
Assuntos
Glucose , Fontes Termais , Glucose/metabolismo , beta-Glucosidase/metabolismo , Escherichia coli/metabolismo , Temperatura , Concentração de Íons de Hidrogênio , Estabilidade Enzimática , Especificidade por SubstratoRESUMO
ß-glucosidases play a pivotal role in second-generation biofuel (2G-biofuel) production. For this application, thermostable enzymes are essential due to the denaturing conditions on the bioreactors. Random amino acid substitutions have originated new thermostable ß-glucosidases, but without a clear understanding of their molecular mechanisms. Here, we probe by different molecular dynamics simulation approaches with distinct force fields and submitting the results to various computational analyses, the molecular bases of the thermostabilization of the Paenibacillus polymyxa GH1 ß-glucosidase by two-point mutations E96K (TR1) and M416I (TR2). Equilibrium molecular dynamic simulations (eMD) at different temperatures, principal component analysis (PCA), virtual docking, metadynamics (MetaDy), accelerated molecular dynamics (aMD), Poisson-Boltzmann surface analysis, grid inhomogeneous solvation theory and colony method estimation of conformational entropy allow to converge to the idea that the stabilization carried by both substitutions depend on different contributions of three classic mechanisms: (i) electrostatic surface stabilization; (ii) efficient isolation of the hydrophobic core from the solvent, with energetic advantages at the solvation cap; (iii) higher distribution of the protein dynamics at the mobile active site loops than at the protein core, with functional and entropic advantages. Mechanisms i and ii predominate for TR1, while in TR2, mechanism iii is dominant. Loop A integrity and loops A, C, D, and E dynamics play critical roles in such mechanisms. Comparison of the dynamic and topological changes observed between the thermostable mutants and the wildtype protein with amino acid co-evolutive networks and thermostabilizing hotspots from the literature allow inferring that the mechanisms here recovered can be related to the thermostability obtained by different substitutions along the whole family GH1. We hope the results and insights discussed here can be helpful for future rational approaches to the engineering of optimized ß-glucosidases for 2G-biofuel production for industry, biotechnology, and science.
Assuntos
Biocombustíveis , beta-Glucosidase , beta-Glucosidase/genética , beta-Glucosidase/química , beta-Glucosidase/metabolismo , Substituição de Aminoácidos , Simulação de Dinâmica Molecular , Domínio CatalíticoRESUMO
Plant specialized metabolites (PSMs) are often stored as glycosides within cells and released from the roots with some chemical modifications. While isoflavones are known to function as symbiotic signals with rhizobia and to modulate the soybean rhizosphere microbiome, the underlying mechanisms of root-to-soil delivery are poorly understood. In addition to transporter-mediated secretion, the hydrolysis of isoflavone glycosides in the apoplast by an isoflavone conjugate-hydrolyzing ß-glucosidase (ICHG) has been proposed but not yet verified. To clarify the role of ICHG in isoflavone supply to the rhizosphere, we have isolated two independent mutants defective in ICHG activity from a soybean high-density mutant library. In the root apoplastic fraction of ichg mutants, the isoflavone glycoside contents were significantly increased, while isoflavone aglycone contents were decreased, indicating that ICHG hydrolyzes isoflavone glycosides into aglycones in the root apoplast. When grown in a field, the lack of ICHG activity considerably reduced isoflavone aglycone contents in roots and the rhizosphere soil, although the transcriptomes showed no distinct differences between the ichg mutants and wild-types (WTs). Despite the change in isoflavone contents and composition of the root and rhizosphere of the mutants, root and rhizosphere bacterial communities were not distinctive from those of the WTs. Root bacterial communities and nodulation capacities of the ichg mutants did not differ from the WTs under nitrogen-deficient conditions either. Taken together, these results indicate that ICHG elevates the accumulation of isoflavones in the soybean rhizosphere but is not essential for isoflavone-mediated plant-microbe interactions.
Assuntos
Isoflavonas , Isoflavonas/química , Glycine max/genética , Glycine max/metabolismo , beta-Glucosidase/genética , beta-Glucosidase/química , Rizosfera , Glicosídeos/metabolismo , Bactérias/metabolismo , SoloRESUMO
Programmed cell death (PCD) in lateral root caps (LRCs) is crucial for maintaining root cap functionality. Endoplasmic reticulum (ER) bodies play important roles in plant immunity and PCD. However, the distribution of ER bodies and their communication with vacuoles in the LRC remain elusive. In this study, we investigated the ultrastructure of LRC cells of wild-type and transgenic Arabidopsis lines using an auto-acquisition transmission electron microscope (TEM) system and high-pressure freezing. Gigapixel-scale high-resolution TEM imaging of the transverse and longitudinal sections of roots followed by three-dimensional imaging identified sausage-shaped structures budding from the ER. These were subsequently identified as ER bodies using GFPh transgenic lines expressing green fluorescent protein (GFP) fused with an ER retention signal (HDEL). Immunogold labeling using an anti-GFP antibody detected GFP signals in the ER bodies and vacuoles. The fusion of ER bodies with vacuoles in LRC cells was identified using correlative light and electron microscopy. Imaging of the root tips of a GFPh transgenic line with a PYK10 promoter revealed the localization of PYK10, a member of the ß-glucosidase family with an ER retention signal, in the ER bodies in the inner layer along with a fusion of ER bodies with vacuoles in the middle layer and collapse of vacuoles in the outer layer of the LRC. These findings suggest that ER bodies in LRC directly transport ß-glucosidases to the vacuoles, and that a subsequent vacuolar collapse triggered by an unknown mechanism releases protective substances to the growing root tip to protect it from the invaders.
Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/metabolismo , beta-Glucosidase/química , beta-Glucosidase/metabolismo , Vacúolos/metabolismo , Retículo Endoplasmático/metabolismo , Arabidopsis/metabolismo , Proteínas de Fluorescência Verde/metabolismoRESUMO
PURPOSE: Most patients with Gaucher disease have progressive and often disabling skeletal manifestations. We examined the long-term effect of eliglustat treatment on bone outcomes in clinical trials in adults with Gaucher disease type 1. METHODS: Data from 4 completed phase 2 and 3 trials were evaluated in treatment-naïve patients or patients switching to eliglustat from enzyme replacement therapy (ERT). RESULTS: Overall, 319 of 393 (81%) eliglustat-treated patients remained in their trials until completion or commercial eliglustat became available. Mean eliglustat treatment duration ranged from 3.3 to 6.5 years. In treatment-naïve patients and ERT-switch patients, frequency and severity of bone pain decreased during eliglustat treatment. Mean lumbar spine T-scores shifted from abnormal to normal in treatment-naïve patients and remained in the healthy reference range or improved modestly in ERT-switch patients. Mean total bone marrow burden score shifted from marked-to-severe to moderate in treatment-naïve patients and remained moderate in ERT-switch patients. MIP-1ß (marker of active bone disease) was elevated at baseline and decreased to the healthy reference range in treatment-naïve patients and remained in the healthy reference range among ERT-switch patients. CONCLUSION: These findings confirm the long-term efficacy of eliglustat on skeletal complications of Gaucher disease in treatment-naïve and ERT-switch patients.
Assuntos
Doença de Gaucher , Adulto , Humanos , Doença de Gaucher/tratamento farmacológico , Inibidores Enzimáticos/uso terapêutico , Pirrolidinas/uso terapêutico , Pirrolidinas/efeitos adversos , Terapia de Reposição de Enzimas , Glucosilceramidase/uso terapêuticoRESUMO
The clinical manifestation of sphingolipidosis leads often to misclassification between acid sphingomyelinase deficiency (ASMD) and Gaucher disease. In this multicenter, prospective study, we investigated a cohort of 31,838 individuals suspected to have Gaucher disease, due to clinical presentation, from 61 countries between 2017 and 2022. For all samples, both Acid-ß-glucocerebrosidase and acid sphingomyelinase enzyme activities were measured in dried blood spot specimens by tandem mass spectrometry followed by genetic confirmatory testing in potential positive cases. In total, 5933 symptomatic cases showed decreased enzyme activities and were submitted for genetic confirmatory testing. 1411/5933 (24%) cases were finally identified with Gaucher disease and 550/5933 (9%) with ASMD. Most of the confirmed ASMD cases were newborns and children below 2 years of age (63%). This study reveals that one in four cases suspected for Gaucher disease is diagnosed with ASMD. An early appropriate diagnostic work-up is essential because of the availability of a recently approved enzyme replacement therapy for ASMD. In conclusion, a diagnostic strategy using differential biochemical testing including genetic confirmatory testing in clinically suspected cases for sphingolipidosis is highly recommended.
Assuntos
Doença de Gaucher , Doença de Niemann-Pick Tipo A , Doenças de Niemann-Pick , Criança , Humanos , Recém-Nascido , Doença de Niemann-Pick Tipo A/diagnóstico , Doença de Niemann-Pick Tipo A/genética , Doença de Gaucher/diagnóstico , Doença de Gaucher/genética , Estudos Prospectivos , Doenças de Niemann-Pick/diagnóstico , Doenças de Niemann-Pick/genética , Esfingomielina Fosfodiesterase/genética , Espectrometria de Massas em Tandem/métodosRESUMO
The enzymatic conversion of lignocellulosic biomass to bioethanol depends on efficient enzyme systems with ß-glucosidase as one of the key components. In this study, we performed in-depth profiling of the various ß-glucosidases present in the genome of the hypercellulolytic fungus Penicillium funiculosum using genomics, transcriptomics, proteomics, and molecular dynamics simulation approaches. Of the eight ß-glucosidase genes identified in the P. funiculosum genome, three were predicted to be extracellular based on signal peptide prediction and abundance in the secretome. Among the three secreted ß-glucosidases, two belonged to the GH3 family and one belonged to the GH1 family. Homology models of these proteins predicted a deep and narrow active site for the GH3 ß-glucosidases (PfBgl3A and PfBgl3B) and a shallow open active site for the GH1 ß-glucosidase (PfBgl1A). The enzymatic assays indicated that P. funiculosum-secreted proteins showed high ß-glucosidase activities with prominent bands on the 4-methylumbelliferyl ß-D-glucopyranoside zymogram. To understand the contributory effects of each of the three secreted ß-glucosidases (PfBgls), the corresponding gene was deleted separately, and the effect of the deletion on the ß-glucosidase activity of the secretome was examined. Although not the most abundant, PfBgl3A was found to be one of the most important ß-glucosidases, as evidenced by a 42% reduction in ß-glucosidase activity in the ΔPfBgl3A strain. Our results advance the understanding of the genetic and biochemical nature of all ß-glucosidases produced by P. funiculosum and pave the way to design a superior biocatalyst for the hydrolysis of lignocellulosic biomass. IMPORTANCE Commercially available cellulases are primarily produced from Trichoderma reesei. However, external supplementation of the cellulase cocktail from this host with exogenous ß-glucosidase is often required to achieve the desired optimal saccharification of cellulosic feedstocks. This challenge has led to the exploration of other cellulase-producing strains. The nonmodel hypercellulolytic fungus Penicillium funiculosum has been studied in recent times and identified as a promising source of industrial cellulases mainly due to its ability to produce a balanced concoction of cellulolytic enzymes, including ß-glucosidases. Various genetic interventions targeted at strain improvement for cellulase production have been performed; however, the ß-glucosidases of this strain have remained largely understudied. This study, therefore, reports profiling of all eight ß-glucosidases of P. funiculosum via molecular and computational approaches. The results of this study provide useful insights that will establish the background for future engineering strategies to transform this fungus into an industrial workhorse.
Assuntos
Celulase , Trichoderma , Celulase/metabolismo , Proteômica , beta-Glucosidase/genética , beta-Glucosidase/metabolismo , Simulação de Dinâmica Molecular , Transcriptoma , Genômica , Trichoderma/genéticaRESUMO
BACKGROUND: A high concentration of CO2 will stagnate the development of the newly formed primordia of Hypsizygus marmoreus, hinder the development of the mushroom cap, thereby inhibiting the normal differentiation of the fruiting body. Moreover, in the previous experiment, our research group obtained the mutant strain HY68 of H. marmoreus, which can maintain normal fruiting under the condition of high concentration of CO2. Our study aimed to evaluate the CO2 tolerance ability of the mutant strain HY68, in comparison with the starting strain HY61 and the control strain HY62. We analyzed the mycelial growth of these strains under various conditions, including different temperatures, pH levels, carbon sources, and nitrogen sources, and measured the activity of the cellulose enzyme. Additionally, we identified and predicted ß-glucosidase-related genes in HY68 and analyzed their gene and protein structures. RESULTS: Our results indicate that HY68 showed superior CO2 tolerance compared to the other strains tested, with an optimal growth temperature of 25 °C and pH of 7, and maltose and beef paste as the ideal carbon and nitrogen sources, respectively. Enzyme activity assays revealed a positive correlation between ß-glucosidase activity and CO2 tolerance, with Gene14147 identified as the most closely related gene to this activity. Inbred strains of HY68 showed trait segregation for CO2 tolerance. CONCLUSIONS: Both HY68 and its self-bred offspring could tolerate CO2 stress. The fruiting period of the strains resistant to CO2 stress was shorter than that of the strains not tolerant to CO2 stress. The activity of ß-GC and the ability to tolerate CO2 were more closely related to the growth efficiency of fruiting bodies. This study lays the foundation for understanding how CO2 regulates the growth of edible fungi, which is conducive to the innovation of edible fungus breeding methods. The application of the new strain HY68 is beneficial to the research of energy-saving production in factory cultivation.