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1.
Curr Issues Mol Biol ; 43(2): 687-703, 2021 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-34287263

RESUMEN

Cellulases have been used to extract bioactive ingredients from medical plants; however, the poor enzymatic properties of current cellulases significantly limit their application. Two strategies are expected to address this concern: (1) new cellulase gene mining strategies have been promoted, optimized, and integrated, thanks to the improvement of gene sequencing, genomic data, and algorithm optimization, and (2) known cellulases are being modified, thanks to the development of protein engineering, crystal structure data, and computing power. Here, we focus on mining strategies and provide a systemic overview of two approaches based on sequencing and function. Strategies based on protein structure modification, such as introducing disulfide bonds, proline, salt bridges, N-glycosylation modification, and truncation of loop structures, have already been summarized. This review discusses four aspects of cellulase-assisted extraction. Initially, cellulase alone was used to extract bioactive substances, and later, mixed enzyme systems were developed. Physical methods such as ultrasound, microwave, and high hydrostatic pressure have assisted in improving extraction efficiency. Cellulase changes the structure of biomolecules during the extraction process to convert them into effective ingredients with better activity and bioavailability. The combination of cellulase with other enzymes and physical technologies is a promising strategy for future extraction applications.


Asunto(s)
Celulasas/química , Minería de Datos , Ingeniería de Proteínas , Celulasas/genética , Celulasas/aislamiento & purificación , Celulasas/metabolismo , Fraccionamiento Químico/métodos , Biología Computacional/métodos , Minería de Datos/métodos , Estabilidad de Enzimas , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Plantas Medicinales/química , Plantas Medicinales/enzimología , Plantas Medicinales/genética , Ingeniería de Proteínas/métodos , Relación Estructura-Actividad
2.
Methods Mol Biol ; 2290: 115-127, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34009586

RESUMEN

Glycerol is a promising low-cost solvent for biomass pretreatment since a large amount of glycerol is generated as a by-product in the biodiesel industry. Pretreatment is a method of disintegration of the recalcitrant structure of biomass to enhance the accessibility of cellulose and hemicelluloses to enzymes for complete saccharification. During pretreatment, glycerol breaks the lignin carbohydrate complex and selectively solubilizes lignin. Thus, the glycerol pretreatment improves the accessibility of cellulose to cellulases leading to higher sugar yields. The glycerol pretreatment is carried out at high temperature (>190 °C) to disintegrate the structure of biomass. The glycerol pretreatment in the presence of acid or base catalyst such as H2SO4 or NaOH results in lower pretreatment temperature and higher glucan hydrolysis. This chapter describes the methodology to carry out glycerol pretreatment of sorghum biomass with or without acid/alkali as catalyst and the basic calculations to determine the efficiency of the pretreatment.


Asunto(s)
Celulasas/aislamiento & purificación , Glicerol/química , Sorghum/química , Biocombustibles/análisis , Biomasa , Celulasas/metabolismo , Celulosa/metabolismo , Fermentación , Hidrólisis , Lignina/metabolismo , Polisacáridos/metabolismo , Solventes , Azúcares
3.
Sci Rep ; 11(1): 2489, 2021 01 28.
Artículo en Inglés | MEDLINE | ID: mdl-33510321

RESUMEN

A carefully designed ammonium sulfate precipitation will simplify extraction of proteins and is considered to be a gold standard among various precipitation methods. Therefore, optimization of ammonium sulfate precipitation can be an important functional step in protein purification. The presence of high amounts of ammonium sulphate precludes direct detection of many enzymatically active proteins including reducing sugar assays (e.g. Nelson-Somogyi, Reissig and 3,5-dinitrosalicylic acid methods) for assessing carbohydrases (e.g. laminarinase (ß (1-3)-glucanohydrolase), cellulases and chitinases). In this study, a simple method was developed using laminarin infused agarose plate for the direct analysis of the ammonium sulphate precipitates from Streptomyces rimosus AFM-1. The developed method is simple and convenient that can give accurate results even in presence of ammonium sulfate in the crude precipitates. Laminarin is a translucent substrate requiring the use of a stain to visualize the zones of hydrolysis in a plate assay. A very low-cost and locally available fluorescent optical fabric brightener Tinopal CBS-X has been used as a stain to detect the zones of hydrolysis. We also report simple methods to prepare colloidal chitin and cell free supernatant in this manuscript.


Asunto(s)
Celulasas , Streptomyces rimosus/enzimología , Proteínas Bacterianas/química , Proteínas Bacterianas/aislamiento & purificación , Celulasas/química , Celulasas/aislamiento & purificación , Laminaria/química
4.
Folia Microbiol (Praha) ; 66(1): 25-40, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33184763

RESUMEN

Detergent enzymes are currently added to all powder and liquid detergents that are manufactured. Cellulases, lipases, amylases, and proteases are used in the detergency to replace toxic phosphates and silicates and to reduce high energy consumption. This makes the use of enzymes in detergent formulation cost effective. Fungi are producers of important extracellular enzymes for industrial use. The fungal and bacterial cellulases maintain the shape and color of the washed garments. There is a high demand for cellulases at the market by detergent industries. With this high demand, genetic engineering has been a solution due to its high production of detergent-compatible cellulases. Fungi are the famous source for detergent-compatible cellulases production, but still, there is a lack of the cost-effective process of alkaline fungal cellulase production. Review papers on detergent-compatible bacterial cellulase and amylase and detergent-compatible fungal and bacterial proteases and lipases are available, but there is no review on detergent fungal cellulases. This review aims to highlight the production, properties, stability, and compatibility of fungal cellulases. It will help other academic and industrial researchers to study, produce, and commercialize the fungal cellulases with good aspects.


Asunto(s)
Celulasas/química , Detergentes/química , Proteínas Fúngicas/química , Celulasas/genética , Celulasas/aislamiento & purificación , Celulasas/metabolismo , Estabilidad de Enzimas , Proteínas Fúngicas/genética , Proteínas Fúngicas/aislamiento & purificación , Proteínas Fúngicas/metabolismo , Hongos/genética , Hongos/crecimiento & desarrollo , Hongos/aislamiento & purificación , Hongos/metabolismo , Ingeniería Genética
5.
Biotechnol Lett ; 42(10): 1897-1905, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32557119

RESUMEN

Lytic polysaccharide monooxygenases (LPMOs) have emerged as key proteins for depolymerization of cellulose. These copper-containing enzymes oxidize C-1 and/or C-4 bonds in cellulose, promoting increased hydrolysis of the oxidized cellulose chains. The LPMO from Thermoascus aurantiacus, a thermophilic ascomycete fungus, has been extensively studied and has served as a model LPMO. A method was developed to purify the LPMO from culture filtrates of T. aurantiacus along with its native cellobiohydrolase and endoglucanase. The activity of the purified LPMO was measured with a colorimetric assay that established the Topt of the native LPMO at 60 °C. Purification of the components of the T. aurantiacus cellulase mixture also enabled quantification of the amounts of cellobiohydrolase, endoglucanase and LPMO present in the T. aurantiacus culture filtrate, establishing that the LPMO was the most abundant protein in the culture supernatants. The importance of the LPMO to activity of the mixture was demonstrated by saccharifications with Avicel and acid-pretreated corn stover.


Asunto(s)
Proteínas Fúngicas , Oxigenasas de Función Mixta , Thermoascus/enzimología , Biomasa , Celulasas/química , Celulasas/aislamiento & purificación , Celulasas/metabolismo , Celulosa/análisis , Celulosa/metabolismo , Proteínas Fúngicas/química , Proteínas Fúngicas/aislamiento & purificación , Proteínas Fúngicas/metabolismo , Hidrólisis , Oxigenasas de Función Mixta/química , Oxigenasas de Función Mixta/aislamiento & purificación , Oxigenasas de Función Mixta/metabolismo
6.
Int J Biol Macromol ; 160: 964-970, 2020 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-32464205

RESUMEN

The carboxymethylated inulin (CMI) nanoparticles prepared by the salt out method was demonstrated to harvest cellulolytic enzymes (Ez) directly from the clarified fermented broth of Trichoderma harzanium BPGF1. The formation of CMI nanoparticles and entrapment of Ez in CMI was confirmed by scanning electron microscopy and Fourier transform infrared spectroscopy, respectively. A factorial design was developed to maximize enzymes recovery directly from the fermented broth. A maximum of 71.68 ± 8.61% cellulolytic enzymes was recovered using 20 mg/L inulin, 2 M sodium chloroacetate at 80 °C for 2 h. The resultant CMIEz nanohybrid displayed excellent activity in broad pH and temperature. Moreover, CMIEz was reusable for >30 cycles without losing efficiency. The real-time application of CMIEz was demonstrated by hydrolyzing acid pretreated corncob. High-pressure liquid chromatography revealed that the hydrolyzed corncob contained cellobiose, glucose, galactose, xylose, mannose, and arabinose. The results highlight that carbohydrate nanoparticles was useful in engulfing enzymes directly from the fermentation broth.


Asunto(s)
Celulasas/química , Celulasas/aislamiento & purificación , Fermentación , Inulina/química , Nanopartículas/química , Trichoderma/enzimología , Carboximetilcelulosa de Sodio , Estabilidad de Enzimas , Concentración de Iones de Hidrógeno , Hidrólisis , Espectroscopía de Resonancia Magnética , Nanopartículas/ultraestructura , Espectroscopía Infrarroja por Transformada de Fourier
7.
Probiotics Antimicrob Proteins ; 12(4): 1555-1561, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32378078

RESUMEN

The effects of non-authochtonous Enterococcus faecium AL41 = CCM 8558, enterocin M-producing and probiotic strain were tested on the microbiota, phagocytic activity, hydrolytic enzymes, biochemical parameters and dry matter in horses based on its previous benefits demonstrated in other animals. E. faecium CCM 8558 sufficiently colonized the digestive tract of horses. At day 14, its counts reached 2.35 ± 0.70 CFU/g (log 10) on average. The identity of CCM 8558 was confirmed by means of PCR after its re-isolation from horse faeces. The inhibition activity of CCM 8558 was demonstrated against Gram-negative aeromonads, counts of which were significantly reduced (P < 0.001). After 14 days application of CCM 8558, a tendency towards increased phagocytic activity (PA) was measured; PA value was 73.13% ± 8.55 on average at day 0/1; at day 14, it was 75.11 ± 8.66%. Cellulolytic, xylanolytic and pectinolytic activity in horse faeces was significantly increased (P < 0.001) at day 14 (after CCM 8558 application) and amylolytic activity as well (P < 0.01) compared to day 0/1. Inulolytic activity increased with mathematical difference 1.378. Dry matter value reached 20.81 ± 2.29% on average at day 0/1; at day 14, it was 20.77 ± 2.59% (P = 0.9725). Biochemical parameters were influenced mostly in the physiological range. These results achieved after application of CCM 8558 in horses are original, giving us further opportunity to continue these studies, to measure additional parameters and to show the benefits of CCM 8558 application in horses.


Asunto(s)
Enterococcus faecium/metabolismo , Microbioma Gastrointestinal/fisiología , Caballos/microbiología , Fagocitosis/efectos de los fármacos , Probióticos/administración & dosificación , Amilasas/aislamiento & purificación , Amilasas/metabolismo , Animales , Hidrocarburos Aromáticos con Puentes/metabolismo , Celulasas/aislamiento & purificación , Celulasas/metabolismo , Recuento de Colonia Microbiana , Enterococcus faecium/química , Heces/microbiología , Glicósido Hidrolasas/aislamiento & purificación , Glicósido Hidrolasas/metabolismo , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Gramnegativas/crecimiento & desarrollo , Monocitos/citología , Monocitos/efectos de los fármacos , Monocitos/inmunología , Neutrófilos/citología , Neutrófilos/efectos de los fármacos , Neutrófilos/inmunología , Poligalacturonasa/aislamiento & purificación , Poligalacturonasa/metabolismo , Xilosidasas/aislamiento & purificación , Xilosidasas/metabolismo
8.
Microb Cell Fact ; 18(1): 97, 2019 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-31151435

RESUMEN

BACKGROUND: Transglycosylation represents one of the most promising approaches for obtaining novel glycosides, and plant phenols and polyphenols are emerging as one of the best targets for creating new molecules with enhanced capacities. These compounds can be found in diet and exhibit a wide range of bioactivities, such as antioxidant, antihypertensive, antitumor, neuroprotective and anti-inflammatory, and the eco-friendly synthesis of glycosides from these molecules can be a suitable alternative for increasing their health benefits. RESULTS: Transglycosylation experiments were carried out using different GH3 ß-glucosidases from the fungus Talaromyces amestolkiae. After a first screening with a wide variety of potential transglycosylation acceptors, mono-glucosylated derivatives of hydroxytyrosol, vanillin alcohol, 4-hydroxybenzyl alcohol, and hydroquinone were detected. The reaction products were analyzed by thin-layer chromatography, high-pressure liquid chromatography, and mass spectrometry. Hydroxytyrosol and vanillyl alcohol were selected as the best options for transglycosylation optimization, with a final conversion yield of 13.8 and 19% of hydroxytyrosol and vanillin glucosides, respectively. NMR analysis confirmed the structures of these compounds. The evaluation of the biological effect of these glucosides using models of breast cancer cells, showed an enhancement in the anti-proliferative capacity of the vanillin derivative, and an improved safety profile of both glucosides. CONCLUSIONS: GH3 ß-glucosidases from T. amestolkiae expressed in P. pastoris were able to transglycosylate a wide variety of acceptors. Between them, phenolic molecules like hydroxytyrosol, vanillin alcohol, 4-hydroxybenzyl alcohol, and hydroquinone were the most suitable for its interesting biological properties. The glycosides of hydroxytyrosol and vanillin were tested, and they improved the biological activities of the original aglycons on breast cancer cells.


Asunto(s)
Neoplasias de la Mama , Celulasas/metabolismo , Glicósidos/farmacología , Talaromyces/enzimología , Benzaldehídos/metabolismo , Alcoholes Bencílicos/metabolismo , Celulasas/química , Celulasas/aislamiento & purificación , Glicósidos/química , Glicósidos/aislamiento & purificación , Glicosilación , Humanos , Hidroquinonas/metabolismo , Células MCF-7 , Alcohol Feniletílico/análogos & derivados , Alcohol Feniletílico/metabolismo , Especificidad por Sustrato
9.
J Basic Microbiol ; 59(2): 134-147, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30421443

RESUMEN

Cellulases, lipases, proteases, and amylases are employed in the detergent preparation to speed up the detergency process. Microbial cellulases are now commercially manufactured and are being used by various industries like detergent industry. Currently, the supplementation of detergent-compatible enzymes is a new trend followed by most of the detergent industries. The cellulases are supplemented to the detergents to improve the fabric smoothness and soil removal without damaging them. They act by passing through the textile interfibril spaces and thus the fabric quality is preserved. The process is environment friendly, and the use of cellulases and other detergent-compatible enzymes diminishes the utilization of toxic detergent constituents that are hazardous to humans. Alkaline cellulases active at ambient and low temperature are now preferred to maintain the fabric quality and use of low energy. The review reports on the production, purification, and properties studies of detergent-compatible proteases, amylases, and lipases are available. However, there is no report on detergent-compatible bacterial cellulases. In the present review, an overview on the production, purification, and characterization of detergent bacterial cellulases is presented. The stability and compatibility of the alkaline bacterial cellulases in the presence of the detergents and the detergent constituents are also discussed.


Asunto(s)
Bacterias/enzimología , Celulasas , Detergentes/química , Bacterias/clasificación , Bacterias/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/aislamiento & purificación , Proteínas Bacterianas/metabolismo , Biotecnología , Carbono/metabolismo , Carboximetilcelulosa de Sodio/metabolismo , Celulasas/clasificación , Celulasas/efectos de los fármacos , Celulasas/aislamiento & purificación , Celulasas/metabolismo , Frío , Medios de Cultivo/química , Estabilidad de Enzimas , Concentración de Iones de Hidrógeno , Cinética , Metales/farmacología , Nitrógeno/metabolismo , Especificidad por Sustrato , Tensoactivos/farmacología , Textiles
10.
Prep Biochem Biotechnol ; 48(9): 777-786, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30303453

RESUMEN

The objective of the present study was to optimize parameters for the cultivation of Lichtheimia corymbifera (mesophilic) and Byssochlamys spectabilis (thermophilic) for the production of ß-glucosidases and to compare the catalytic and thermodynamic properties of the partially purified enzymes. The maximum amount of ß-glucosidase produced by L. corymbifera was 39 U/g dry substrate (or 3.9 U/mL), and that by B. spectabilis was 77 U/g (or 7.7 U/mL). The optimum pH and temperature were 4.5 and 55 °C and 4.0 and 50 °C for the enzyme from L. corymbifera and B. spectabilis, respectively. ß-Glucosidase produced by L. corymbifera was stable at pH 4.0-7.5, whereas the enzyme from B. spectabilis was stable at pH 4.0-6.0. Regarding the thermostability, ß-glucosidase produced by B. spectabilis remained stable for 1 h at 50 °C, and that from L. corymbifera was active for 1 h at 45 °C. Determination of thermodynamic parameters confirmed the greater thermostability of the enzyme produced by the thermophilic fungus B. spectabilis, which showed higher values of ΔH, activation energy for denaturation (Ea), and half-life t(1/2). The enzymes were stable in the presence of ethanol and were competitively inhibited by glucose. These characteristics contribute to their use in the simultaneous saccharification and fermentation of vegetable biomass.


Asunto(s)
Byssochlamys/enzimología , Celulasas/química , Proteínas Fúngicas/química , Mucorales/enzimología , Byssochlamys/crecimiento & desarrollo , Catálisis , Celulasas/antagonistas & inhibidores , Celulasas/aislamiento & purificación , Técnicas de Cultivo/métodos , Inhibidores Enzimáticos/química , Etanol/química , Proteínas Fúngicas/antagonistas & inhibidores , Proteínas Fúngicas/aislamiento & purificación , Glucosa/química , Concentración de Iones de Hidrógeno , Cinética , Mucorales/crecimiento & desarrollo , Temperatura , Termodinámica
11.
Phytochemistry ; 156: 224-233, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30336442

RESUMEN

In the plant kingdom beta-glucosidases (BGLUs) of the glycosidase hydrolase family 1 have essential function in primary metabolism and are particularly employed in secondary metabolism. They are essential for activation in two-component defence systems based on stabilisation of reactive compounds by glycosylation. Based on de novo assembly we isolated and functionally characterised BGLUs expressed in leaves of Lamium galeobdolon (LgGLUs). LgGLU1 could be assigned to hydrolysis of the benzoxazinoid GDIBOA (2,4-dihydroxy-1,4-benzoxazin-3-one glucoside). Within the Lamiaceae L. galeobdolon is distinguished by the presence GDIBOA in addition to the more common iridoid harpagide. Although LgGLU1 proved to be promiscuous with respect to accepted substrates, harpagide hydrolysis was not detected. Benzoxazinoids are characteristic defence compounds of the Poales but are also found in some unrelated dicots. The benzoxazinoid specific BGLUs have recently been identified for the grasses maize, wheat, rye and the Ranunculaceae Consolida orientalis. All enzymes share a general substrate ambiguity but differ in detailed substrate pattern. The isolation of the second dicot GDIBOA glucosidase LgGLU1 allowed it to analyse the phylogenetic relation of the distinct BGLUs also within dicots. The data revealed long periods of independent sequence evolution before speciation.


Asunto(s)
Benzoxazinas/metabolismo , Celulasas/metabolismo , Lamiaceae/enzimología , Benzoxazinas/química , Celulasas/aislamiento & purificación , Glicosilación , Lamiaceae/metabolismo
12.
Electron. j. biotechnol ; 34: 29-36, july. 2018. ilus, tab, graf
Artículo en Inglés | LILACS | ID: biblio-1045993

RESUMEN

Background: Recombinant DNA technology enables us to produce proteins with desired properties and insubstantial amount for industrial applications. Endo-1, 4-ß-glucanases (Egl) is one of the major enzyme involved in degradation of cellulose, an important component of plant cell wall. The present study was aimed at enhancing the production of endo-1, 4-ß-glucanases (Egl) of Bacillus halodurans in Escherichia coli. Results: A putative Egl gene of Bacillus Halodurans was expressed in E. coli by cloning in pET 22b (+). On induction with isopropyl-b-D-1-thiogalactopyranoside, the enzyme expression reached upto ~20% of the cell protein producing 29.2 mg/liter culture. An increase in cell density to 12 in auto-inducing LB medium (absorbance at 600 nm) enhanced ß-glucanase production up to 5.4 fold. The molecular mass of the enzyme was determined to be 39 KDa, which is nearly the same as the calculated value. Protein sequence was analyzed by CDD, Pfam, I TASSER, COACH, PROCHECK Servers and putative amino acids involved in the formation of catalytic, substrate and metal binding domains were identified. Phylogenetic analysis of the ß-glucanases of B. halodurans was performed and position of Egl among other members of the genus Bacillus producing endo-glucanases was determined. Temperature and pH optima of the enzyme were found to be 60°C and 8.0, respectively, under the assay conditions. Conclusion: Production of endo-1, 4 ß-glucanase enzymes from B. halodurans increased several folds when cloned in pET vector and expressed in E. coli. To our knowledge, this is the first report of high-level expression and characterization of an endo-1, 4 ß-glucanases from B. halodurans.


Asunto(s)
Bacillus/enzimología , Celulasas/biosíntesis , Temperatura , Estabilidad de Enzimas , Expresión Génica , Pared Celular/enzimología , Reacción en Cadena de la Polimerasa , Clonación Molecular , Celulasas/aislamiento & purificación , Celulasas/metabolismo , Escherichia coli/metabolismo , Células Vegetales/enzimología , Concentración de Iones de Hidrógeno , Hidrólisis
13.
Methods Mol Biol ; 1796: 37-45, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29856044

RESUMEN

Filamentous fungi are among the microorganisms that most efficiently are able to degrade plant biomass by secreting cell wall-degrading enzymes and they are therefore used extensively in the industry as workhorses for the production of enzymes, including cellulases for the use in second-generation biorefinery concepts. Fungi are therefore of interest both as resources for the search of novel cellulolytic enzymes and for production of enzymes and enzyme cocktails, which also can be carried out on-site using cheap lignocellulosic substrates for growth and enzyme production. Fungi can be isolated from different environmental niches, such as soil, compost, decaying wood, decaying plant material, building materials, and different foodstuffs. Selective isolation can be carried out using simple cellulosic or complex plant material in the media. In this chapter, methods used for the isolation and screening of cellulolytic fungi isolated from different ecological niches are presented. The screening assay presented in the chapter is an easy semiquantitative high-throughput agar plate screening method using azurine-cross-linked (AZCL) cellulose substrates.


Asunto(s)
Celulosa/metabolismo , Hongos/aislamiento & purificación , Hongos/metabolismo , Biología Molecular/métodos , Celulasas/aislamiento & purificación , Medios de Cultivo , Hongos/enzimología
14.
Biotechnol Lett ; 40(7): 1119-1126, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29779122

RESUMEN

OBJECTIVE: Improve the hydrolysis efficiency of the Trichoderma reesei cellulase system by heterologously expressing cellobiohydrolase Cel7A (Te-Cel7A) from the thermophilic fungus Talaromyces emersonii. RESULTS: Te-Cel7A was expressed in T. reesei under control of the cdna1 promoter and the generated transformant QTC14 could successfully secrete Te-Cel7A into the supernatant using glucose as carbon source. The recombinant Te-Cel7A had a temperature optimum at 65 °C and an optimal pH of 5, which were similar to those from the native host. The culture supernatant of QTC14 exhibited a 28.8% enhancement in cellobiohydrolase activity and a 65.2% increase in filter paper activity relative to that of the parental strain QP4. Moreover, the QTC14 cellulase system showed higher thermal stability than that of the parental strain QP4. In the saccharification of delignified corncob residue, the cellulose conversion of QTC14 showed 13.9% higher than that of QP4 at the end of reaction. CONCLUSIONS: The thermophilic fungus-derived cellulases could be efficiently expressed by T. reesei and the recombinant cellulases had potential applications for biomass conversion.


Asunto(s)
Celulasas/metabolismo , Proteínas Fúngicas/metabolismo , Proteínas Recombinantes/metabolismo , Talaromyces/enzimología , Trichoderma/genética , Zea mays/química , Biomasa , Celulasas/química , Celulasas/genética , Celulasas/aislamiento & purificación , Estabilidad de Enzimas , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/aislamiento & purificación , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Talaromyces/genética
15.
Sci Rep ; 7(1): 11425, 2017 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-28900273

RESUMEN

Laminarinase from Flavobacterium sp. strain UMI-01, a new member of the glycosyl hydrolase 16 family of a marine bacterium associated with seaweeds, mainly degrades ß-1,3-glucosyl linkages of ß-glucan (such as laminarin) through the hydrolysis of glycosidic bonds. We determined the crystal structure of ULam111 at 1.60-Å resolution to understand the structural basis for its thermostability and substrate specificity. A calcium-binding motif located on the opposite side of the ß-sheet from catalytic cleft increased its degrading activity and thermostability. The disulfide bridge Cys31-Cys34, located on the ß2-ß3 loop near the substrate-binding site, is responsible for the thermostability of ULam111. The substrates of ß-1,3-linked laminarin and ß-1,3-1,4-linked glucan bound to the catalytic cleft in a completely different mode at subsite -3. Asn33 and Trp113, together with Phe212, formed hydrogen bonds with preferred substrates to degrade ß-1,3-linked laminarin based on the structural comparisons. Our structural information provides new insights concerning thermostability and substrate recognition that will enable the design of industrial biocatalysts.


Asunto(s)
Celulasas/química , Celulasas/metabolismo , Flavobacterium/enzimología , Termodinámica , Sitios de Unión , Dominio Catalítico , Celulasas/genética , Celulasas/aislamiento & purificación , Activación Enzimática , Estabilidad de Enzimas , Flavobacterium/genética , Modelos Moleculares , Unión Proteica , Conformación Proteica , Relación Estructura-Actividad , Especificidad por Sustrato
16.
J Basic Microbiol ; 57(8): 653-658, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28503798

RESUMEN

Neutral and alkaline cellulases from microorganisms constitute a major group of the industrial enzymes and find applications in various industries. Screening is the important ways to get novel cellulases. Most fungal cellulases have acidic pH optima, except some fungi like Humicola insolens species. However, new applications require the use of neutral and alkaline cellulases in food, brewery and wine, animal feed, textile and laundry, pulp and paper industries, agriculture as well in scientific research purposes. Indeed, the demand for these enzymes is growing more rapidly than ever before, and becomes the driving force for research on engineering the cellulolytic enzymes. Here, we present an overview of the biotechnological research for neutral and alkaline cellulases.


Asunto(s)
Celulasas/aislamiento & purificación , Celulasas/metabolismo , Microbiología Industrial , Biotecnología , Celulasas/química , Hongos/enzimología , Concentración de Iones de Hidrógeno
17.
Biosci Biotechnol Biochem ; 81(7): 1289-1299, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28489493

RESUMEN

Schizophyllum commune is a basidiomycete equipped with an efficient cellulolytic enzyme system capable of growth on decaying woods. In this study, production of lignocellulose-degrading enzymes from S. commune mutant G-135 (SC-Cel) on various cellulosic substrates was examined. The highest cellulase activities including CMCase, FPase, and ß-glucosidase were obtained on Avicel-PH101 while a wider range of enzymes attacking non-cellulosic polysaccharides and lignin were found when grown on alkaline-pretreated biomass. Proteomic analysis of SC-Cel also revealed a complex enzyme system comprising seven glycosyl hydrolase families with an accessory carbohydrate esterase, polysaccharide lyase, and auxiliary redox enzymes. SC-Cel obtained on Avicel-PH101 effectively hydrolyzed all agricultural residues with the maximum glucan conversion of 98.0% using corn cobs with an enzyme dosage of 5 FPU/g-biomass. The work showed potential of SC-Cel on hydrolysis of various herbaceous biomass with enhanced efficiency by addition external ß-xylosidase.


Asunto(s)
Celulasas/química , Celulosa/química , Proteínas Fúngicas/química , Lignina/química , Proteoma/metabolismo , Schizophyllum/química , Biomasa , Celulasas/aislamiento & purificación , Celulosa/metabolismo , Fermentación , Proteínas Fúngicas/aislamiento & purificación , Expresión Génica , Hidrólisis , Isoenzimas/química , Isoenzimas/aislamiento & purificación , Lignina/metabolismo , Mutación , Oryza/química , Proteoma/genética , Saccharum/química , Schizophyllum/enzimología , Schizophyllum/genética , Residuos , Madera/química , Xilosidasas/química , Zea mays/química
18.
Biotechnol Appl Biochem ; 64(2): 174-186, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26790627

RESUMEN

In recent years, there have been particular emphases worldwide on the development and optimization of bioprocesses for the utilization of biomass. An essential component of the biomass processing conduit has been the need for robust biocatalysts as high-performance tools for both the depolymerization of lignocellulosic biomass and synthesis of new high-value bio-based chemical entities. Through functional screening of the metagenome of the hindgut bacterial symbionts of a termite, Trinervitermes trinervoides, we discovered open reading frames for 25 cellulases and hemicellulases. These were classified into 14 different glycoside hydrolase (GH) families: eight GH family 5; four GH9, two GH13, and one each in GH2, GH10, GH11, GH26, GH29, GH43, GH44, GH45, GH67, and GH94 families. Of these, eight were overexpressed and partially characterized to be shown to be endocellulases (GH5C, GH5E, GH5F, and GH5G), an exocellulase (GH5D), endoxylanases (GH5H and GH11), and an α-fucosidase (GH29). The GH11 (Xyl1) was of particular interest as it was discovered to be a multimodular ß-1,4-xylanase, consisting of a catalytic domain and two carbohydrate-binding modules (CBMs). The CBM functions to selectively bind insoluble xylan and increases the rate of hydrolysis. The primary structure of GH11 showed a classical catalytic dyad of glutamic acid residues that generally forms part of the active site in GH11 enzyme family. This endoxylanase was optimal at pH 6 and 50 °C, and generated xylobiose and xylotriose from various xylan sources, including beechwood, birchwood, and wheat arabinoxylan. The catalytic ability of GH11 against natural substrate (e.g., wheat arabinoxylan) renders GH11 as a potential useful biocatalyst in the effective dismantling of complex plant biomass architecture.


Asunto(s)
Microbioma Gastrointestinal/genética , Glicósido Hidrolasas/genética , Isópteros/microbiología , Metagenómica , Animales , Celulasas/química , Celulasas/clasificación , Celulasas/genética , Celulasas/aislamiento & purificación , Glicósido Hidrolasas/química , Glicósido Hidrolasas/clasificación , Glicósido Hidrolasas/aislamiento & purificación , Hidrólisis , Isópteros/enzimología , Isópteros/genética , Conformación Proteica , Relación Estructura-Actividad , Especificidad por Sustrato , Simbiosis/genética
19.
Electron. j. biotechnol ; 19(6): 56-62, Nov. 2016. ilus
Artículo en Inglés | LILACS | ID: biblio-840314

RESUMEN

Background: Endoglucanase, one of three type cellulases, can randomly cleave internal p-1,4-linkages in cellulose polymers. Thus, it could be applied in agricultural and industrial processes. Results: A novel endoglucanase gene (JqCel5A) was cloned from Jonesia quinghaiensis and functionally expressed in Escherichia coli Rosetta (DE3). It contained 1722 bp and encoded a 573-residue polypeptide consisting of a catalytic domain of glycoside hydrolase family 5 (GH5) and a type 2 carbohydrate-binding module (CBM2), together with a predicted molecular mass of 61.79 kD. The purified JqCel5A displayed maximum activity at 55°C and pH 7.0, with 21.7 U/mg, 26.19 U/mg and 4.81 U/mg towards the substrate carboxymethyl cellulose, barley glucan and filter paper, respectively. Interestingly, JqCel5A exhibited high pH stability over a broad pH range of pH (3-11), and had good tolerance to a wide variety of deleterious chemicals including heavy metals and detergent. The catalytic mechanism of JqCel5A was also investigated by site mutagenesis and homology-modeling in this study. Conclusions: It was believed that these properties might make JqCel5A to be potentially used in the suitable industrial catalytic condition, which has a broad pH fluctuation and/or chemical disturbance.


Asunto(s)
Actinomycetales/enzimología , Celulasas/química , Celulasas/aislamiento & purificación , Celulasas/genética , Concentración de Iones de Hidrógeno , Pruebas de Mutagenicidad , Temperatura
20.
Cell Physiol Biochem ; 39(4): 1479-94, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27607466

RESUMEN

BACKGROUND/AIMS: Pleurotus eryngii is one of the most valued and delicious mushrooms which are commercially cultivated on various agro-wastes. How different substrates affect lignocellulosic biomass degradation, lignocellulosic enzyme production and biological efficiency in Pleurotus eryngii was unclear. METHODS AND RESULTS: In this report, Pleurotus eryngii was cultivated in substrates including ramie stalks, kenaf stalks, cottonseed hulls and bulrush stalks. The results showed that ramie stalks and kenaf stalks were found to best suitable to cultivate Pleurotus eryngii with the biological efficiency achieved at 55% and 57%, respectively. In order to establish correlations between different substrates and lignocellulosic enzymes expression, the extracellular proteins from four substrates were profiled with high throughput TMT-based quantitative proteomic approach. 241 non-redundant proteins were identified and 74 high confidence lignocellulosic enzymes were quantified. Most of the cellulases, hemicellulases and lignin depolymerization enzymes were highly up-regulated when ramie stalks and kenaf stalks were used as carbon sources. The enzyme activities results suggested cellulases, hemicellulases and lignin depolymerization enzymes were significantly induced by ramie stalks and kenaf stalks. CONCLUSION: The lignocelluloses degradation, most of the lignocellulosic enzymes expressions and activities of Pleurotus eryngii had positive correlation with the biological efficiency, which depend on the nature of lignocellulosic substrates. In addition, the lignocellulosic enzymes expression profiles during Pleurotus eryngii growth in different substrates were obtained. The present study suggested that most of the lignocellulosic enzymes expressions and activities can be used as tools for selecting better performing substrates for commercial mushroom cultivation.


Asunto(s)
Celulasas/metabolismo , Proteínas Fúngicas/metabolismo , Glicósido Hidrolasas/metabolismo , Lignina/metabolismo , Pleurotus/enzimología , Biomasa , Celulasas/genética , Celulasas/aislamiento & purificación , Productos Agrícolas , Pruebas de Enzimas , Proteínas Fúngicas/genética , Proteínas Fúngicas/aislamiento & purificación , Expresión Génica , Glicósido Hidrolasas/genética , Glicósido Hidrolasas/aislamiento & purificación , Hidrólisis , Lignina/química , Anotación de Secuencia Molecular , Pleurotus/genética , Proteómica/métodos , Especificidad por Sustrato , Residuos
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