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1.
Biotechnol Appl Biochem ; 68(5): 1067-1075, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32919432

RESUMEN

In the present study, the phytase enzyme was purified from Lactobacillus plantarum with a 3.08% recovery, 9.57-purification fold, and with a specific activity of 278.82 EU/mg protein. Then, the effects of the 5 EU and 10 EU purified phytase was determined on the plant growth, quality, the macro-micro nutrient content of pansy (Viola × wittrockiana), which is of great importance in ornamental plants industry. The research was established under greenhouse conditions with natural light in 2017. The pansy seeds were coated with phytase enzyme solution, sown in a peat environment, and transferred to pots at the seedling period. In general, the 5 EU and 10 EU applications increase plant height, the number of leaves per plant, the number of side branches per plant, and flower height parameters compared to control. Also, micro- and macronutrient values in soil and plant samples were examined. According to the results, the phytase application on pansy cultivation positively affected the properties and yielded high quality of plants.


Asunto(s)
6-Fitasa/aislamiento & purificación , Lactobacillus plantarum/enzimología , Nutrientes/análisis , Viola/crecimiento & desarrollo , 6-Fitasa/metabolismo , Semillas/química , Semillas/metabolismo , Viola/química , Viola/metabolismo
2.
Bioprocess Biosyst Eng ; 44(10): 2217-2228, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34142205

RESUMEN

Phytase is used in poultry diets to hydrolyze and release of phytate-bound phosphorus. Immobilization on nanomaterials optimizes enzyme's thermal stability and reusability. This study aimed to immobilize the recombinant phytase from Yersinia intermedia on the surface of amino-multi-walled carbon nanotubes (amino-MWCNTs) by physical adsorption. For this, zeta potential measurement, FTIR spectroscopic analysis, scanning electron microscope (SEM), kinetic as well as thermodynamic parameters were used to characterize immobilized phytase on amino-MWCNTs. According to results, the optimum temperature of the immobilized phytase increased from 50 to 70 °C and also thermal and pH stability improved considerably. Moreover, immobilization led to an increase in the value of Km and kcat from 0.13 to 0.33 mM and 2220 to 2776 s-1, respectively. In addition, the changes in activation energy of thermal inactivation (ΔE#a (D)), the free energy of thermal inactivation (ΔG#D) and the enthalpy of thermal inactivation (ΔH#D) for immobilized phytase increased by +11.05, +24.7 and +11.4 kj/mole, respectively, while the value of the change in the entropy of thermal inactivation (ΔS#D) decreased by - 0.04 kj/mole.K. Overall, our results showed that adsorption immobilization of phytase on amino-MWCNTs increases thermal, pH and storage stability as well as some of kinetic parameters.


Asunto(s)
6-Fitasa/metabolismo , Nanotubos de Carbono/química , Yersinia/enzimología , 6-Fitasa/aislamiento & purificación , Adsorción , Estabilidad de Enzimas , Cinética , Microscopía Electrónica de Rastreo , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura , Termodinámica
3.
J Basic Microbiol ; 60(9): 787-798, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33448445

RESUMEN

Cereals and pseudocereals are a rich source of nutrients and trace elements, but their dietary bioavailability is low due to the presence of phytate (IP6), an antinutritional compound with the ability to chelate cations and proteins. Phytase is an enzyme that catalyzes the hydrolysis of IP6 and it is used as an additive improving the nutritional quality of grain-based foods. The aim of this study was to select lactic acid bacteria (LAB) isolated from pseudocereals with phytase activity, characterize their production and activity, and purify the enzyme. LAB strains isolated from grains and spontaneous sourdough of quinoa and amaranth were grown in the Man Rogosa and Sharpe medium where the inorganic phosphate (Pi) was replaced by 1% of IP6. Phytase activity was determined by measuring the Pi released from IP6. Phytase of Lactobacillus (L.) plantarum CRL1964 (PhyLP) showed the highest specific activity from 73 LAB evaluated. IP6 induces PhyLP production, which is at its maximum at the end of the exponential phase. PhyLP was thermostable and maintained its activity under acidic conditions. The enzymatic activity is stimulated by ethylenediaminetetraacetic acid, Co2+, and ascorbic acid. PhyLP was partially purified and showed a molecular mass of 55 kDa. L. plantarum CRL1964 and/or PhyLP have the potential to be included in the processing of cereal/pseudocereals based products for animal feed and/or the food industry improving its nutritional value.


Asunto(s)
6-Fitasa/metabolismo , Grano Comestible/microbiología , Lactobacillus plantarum/enzimología , 6-Fitasa/química , 6-Fitasa/aislamiento & purificación , Medios de Cultivo/química , Concentración de Iones de Hidrógeno , Hidrólisis , Lactobacillales/enzimología , Lactobacillales/crecimiento & desarrollo , Lactobacillales/aislamiento & purificación , Lactobacillus plantarum/crecimiento & desarrollo , Lactobacillus plantarum/aislamiento & purificación , Peso Molecular , Fosfatos/metabolismo , Ácido Fítico/metabolismo , Especificidad por Sustrato , Temperatura
4.
Appl Microbiol Biotechnol ; 102(6): 2607-2620, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29417200

RESUMEN

Among the Streptomyces species, Streptomyces lividans has often been used for the production of heterologous proteins as it can secrete target proteins directly into the culture medium. Streptomyces rimosus, on the other hand, has for long been used at an industrial scale for oxytetracycline production, and it holds 'Generally Recognised As Safe' status. There are a number of properties of S. rimosus that make this industrial strain an attractive candidate as a host for heterologous protein production, including (1) rapid growth rate; (2) growth as short fragments, as for Escherichia coli; (3) high efficiency of transformation by electroporation; and (4) secretion of proteins into the culture medium. In this study, we specifically focused our efforts on an exploration of the use of the Sec secretory pathway to export heterologous proteins in a S. rimosus host. We aimed to develop a genetic tool kit for S. rimosus and to evaluate the extracellular production of target heterologous proteins of this industrial host. This study demonstrates that S. rimosus can produce the industrially important enzyme phytase AppA extracellularly, and analogous to E. coli as a host, application of His-Tag/Ni-affinity chromatography provides a simple and rapid approach to purify active phytase AppA in S. rimosus. We thus demonstrate that S. rimosus can be used as a potential alternative protein expression system.


Asunto(s)
6-Fitasa/genética , 6-Fitasa/metabolismo , Fosfatasa Ácida/genética , Fosfatasa Ácida/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Streptomyces rimosus/genética , Streptomyces rimosus/metabolismo , 6-Fitasa/aislamiento & purificación , Fosfatasa Ácida/aislamiento & purificación , Cromatografía de Afinidad , Proteínas de Escherichia coli/aislamiento & purificación , Proteínas Recombinantes/aislamiento & purificación
5.
Prep Biochem Biotechnol ; 48(8): 718-724, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30015561

RESUMEN

A novel protease-resistant and thermostable phytase from Bacillus subtilis subsp. subtilis JJBS250 was purified 36-fold to homogeneity with a combination of ammonium sulfate precipitation followed by Q-Sepharose and Sephadex G-50 chromatographic techniques. The estimated molecular mass of the purified phytase was 46 kDa by electrophoresis with optimal activity at pH 7.0 and 70 °C. About 19% of original activity was maintained at 80 °C for 10 min. Phytase activity was stimulated in presence of surfactants like Tween-20, Tween-80, and Triton X-100 and metal ions like Ca+2, K+, and Co+2 and it was inhibited by SDS and Mg+2, Al+2, and Fe+2. Purified enzyme showed specificity to different salts of phytic acid and values of Km and Vmax were 0.293 mM and 11.49 nmoles s-1, respectively for sodium phytate. The purified enzyme was resistant to proteases (trypsin and pepsin) that resulted in amelioration of food nutrition with simultaneous release of inorganic phosphate, reducing sugars, and soluble protein.


Asunto(s)
6-Fitasa , Bacillus subtilis/enzimología , Proteínas Bacterianas , Calor , Pepsina A/química , Tripsina/química , 6-Fitasa/química , 6-Fitasa/aislamiento & purificación , Proteínas Bacterianas/química , Proteínas Bacterianas/aislamiento & purificación , Estabilidad de Enzimas
6.
J Sci Food Agric ; 98(10): 3667-3674, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29266239

RESUMEN

BACKGROUND: Phytases are a diverse group of enzymes initiating the dephosphorylation of phytate. Phytate is considered as an anti-nutritional compound because of its capability to chelate nutrients such as Fe2+ , Zn2+ , Mg2+ , and Ca2+ . In this study, several bacterial isolates obtained from earthworm casts were evaluated for their phytate degrading capability. Enzymatic properties and the sequence of the corresponding phytase-encoding gene of the selected isolate were determined. RESULTS: The phytase exhibited its highest activity at pH 4.0 and was stable from pH 3 up to pH 9. The temperature optimum was determined to be 65 °C. The strongest inhibitors of enzymatic activity were identified as vanadate, Cu2+ , and Zn2+ . High-performance ion chromatography analysis of enzymatic phytate dephosphorylation revealed that the first dephosphorylation product was d/l-myo-inositol(1,2,3,4,5)pentakisphosphate. CONCLUSION: Owing to its enzymatic properties, such as tolerance to tartrate and the presence of the consensus motifs PDTVY, GNHE, DLG, VLFH, and GHDH, this phytase could be classified as a purple acid phytase. To the best of our knowledge, this is the first report describing a bacterial purple acid phytase. © 2017 Society of Chemical Industry.


Asunto(s)
6-Fitasa/metabolismo , Bacterias/enzimología , Proteínas Bacterianas/metabolismo , Oligoquetos/microbiología , 6-Fitasa/química , 6-Fitasa/genética , 6-Fitasa/aislamiento & purificación , Animales , Bacterias/química , Bacterias/genética , Bacterias/aislamiento & purificación , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/aislamiento & purificación , Estabilidad de Enzimas , Concentración de Iones de Hidrógeno , Ácido Fítico/metabolismo
7.
Appl Microbiol Biotechnol ; 101(7): 2677-2689, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28233043

RESUMEN

Since the discovery of phytic acid in 1903 and phytase in 1907, extensive research has been carried out in the field of phytases, the phytic acid degradatory enzymes. Apart from forming backbone enzyme in the multimillion dollar-based feed industry, phytases extend a multifaceted role in animal nutrition, industries, human physiology, and agriculture. The utilization of phytases in industries is not effectively achieved most often due to the loss of its activity at high temperatures. The growing demand of thermostable phytases with high residual activity could be addressed by the combinatorial use of efficient phytase sources, protein engineering techniques, heterologous expression hosts, or thermoprotective coatings. The progress in phytase research can contribute to its economized production with a simultaneous reduction of various environmental problems such as eutrophication, greenhouse gas emission, and global warming. In the current review, we address the recent advances in the field of various natural as well as recombinant thermotolerant phytases, their significance, and the factors contributing to their thermotolerance.


Asunto(s)
6-Fitasa/genética , 6-Fitasa/metabolismo , Estabilidad de Enzimas , Calor , Ácido Fítico/metabolismo , Ingeniería de Proteínas/métodos , 6-Fitasa/química , 6-Fitasa/aislamiento & purificación , Agricultura/economía , Alimentación Animal/economía , Aspergillus/enzimología , Aspergillus/metabolismo , Escherichia coli/genética , Humanos , Concentración de Iones de Hidrógeno , Pichia/enzimología , Pichia/genética , Pichia/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
8.
J Basic Microbiol ; 55(8): 1029-39, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25727311

RESUMEN

A yeast producing a cold-adapted phytase was isolated from Antarctic deep-sea sediment and identified as a Rhodotorula mucilaginosa strain JMUY14 of basidiomycetous yeasts. It was cultured in fermentation optimized by a response surface methodology based on the Box-Behnken design. The maximum activity of phytase reached 205.447 U ml(-1), which was close to the predicted value of 201.948 U ml(-1) and approximately 3.4 times higher than its initial activity. The extracellular phytase was purified by 15.2-fold to homogeneity with a specific activity of 31,635 U mg(-1) by (NH4 )2 SO4 precipitation, and a combination of DEAE Sepharose Fast Flow, SP Sepharose Fast Flow, and Sephadex G-100. The molecular weight of the purified enzyme was estimated to be 63 kDa and its pI was 4.33. Its optimal temperature and pH were 50 °C and 5.0, respectively. Its activity was 85% at 37 °C, and showed good stability at pH 3.0 ∼ 7.0. When compared with mesophilic counterparts, the phytase not only exhibited a higher activity during 20 ∼ 30 °C but also had a low Km (247 µM) and high kcat (1394 s(-1)). The phytase activity was slightly stimulated in the presence of Mg(2+), Fe(2+), Fe(3+), K(+), Na(+), Ca(2+), EDTA, and EGTA and moderately inhibited by Cu(2+), Zn(2+), Mn(2+), Ag(+), PMSF, SDS, and phenylgloxal hydrate. It was resistant to both pepsin and trypsin. Since the phytase produced by the R. mucilaginosa JMUY14 showed a high specific activity, good pH stability, strong protease resistance, and high activity at low temperature, it has great potential for feed applications, especially in aquaculture.


Asunto(s)
6-Fitasa/aislamiento & purificación , 6-Fitasa/metabolismo , Adaptación Fisiológica , Frío , Sedimentos Geológicos/microbiología , Rhodotorula/enzimología , 6-Fitasa/antagonistas & inhibidores , 6-Fitasa/química , Secuencia de Aminoácidos , Regiones Antárticas , Acuicultura , Estabilidad de Enzimas , Fermentación , Concentración de Iones de Hidrógeno , Cinética , Peso Molecular , Pepsina A/metabolismo , Filogenia , Rhodotorula/aislamiento & purificación , Rhodotorula/fisiología , Especificidad por Sustrato , Tripsina/metabolismo
9.
Prep Biochem Biotechnol ; 45(4): 336-47, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-24839991

RESUMEN

A phytase from Penicillium oxalicum PJ3, PhyA, was purified near to homogeneity with 427-fold increase in specific phytase activity by ammonium sulfate precipitation, gel filtration, and ion-exchange chromatographies. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and zymogram analysis of the purified enzyme indicated an estimated molecular mass of 65 kD. The optimal pH and temperature of the purified enzyme were pH 4.5 and 55°C, respectively. The enzyme activity was strongly inhibited by Ca(2+), Cu(2+), Zn(2+), and phenylmethylsulfonyl fluoride (PMSF). The Km value for sodium phytate was 0.545 mM with a Vmax of 600 U/mg of protein. The phyA gene was cloned, and it contains an open reading frame of 1,383 with a single intron (118 bp), and encodes a protein of 461 amino acids.


Asunto(s)
6-Fitasa/genética , 6-Fitasa/metabolismo , Penicillium/enzimología , 6-Fitasa/antagonistas & inhibidores , 6-Fitasa/aislamiento & purificación , Secuencia de Aminoácidos , Secuencia de Bases , Calcio/farmacología , Cromatografía en Gel , Cromatografía por Intercambio Iónico , Clonación Molecular , Cobre/farmacología , Electroforesis en Gel de Poliacrilamida , Inhibidores Enzimáticos/farmacología , Proteínas Fúngicas/genética , Proteínas Fúngicas/aislamiento & purificación , Proteínas Fúngicas/metabolismo , Concentración de Iones de Hidrógeno , Datos de Secuencia Molecular , Peso Molecular , Penicillium/genética , Fluoruro de Fenilmetilsulfonilo/farmacología , Ácido Fítico/metabolismo , Temperatura , Zinc/farmacología
10.
ScientificWorldJournal ; 2014: 392615, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24688383

RESUMEN

Fermentation is one of the industrially important processes for the development of microbial metabolites that has immense applications in various fields. This has prompted to employ fermentation as a major technique in the production of phytase from microbial source. In this study, a comparison was made between submerged (SmF) and solid-state fermentations (SSF) for the production of phytase from Aspergillus niger CFR 335 and Aspergillus ficuum SGA 01. It was found that both the fungi were capable of producing maximum phytase on 5th day of incubation in both submerged and solid-state fermentation media. Aspergillus niger CFR 335 and A. ficuum produced a maximum of 60.6 U/gds and 38 U/gds of the enzyme, respectively, in wheat bran solid substrate medium. Enhancement in the enzyme level (76 and 50.7 U/gds) was found when grown in a combined solid substrate medium comprising wheat bran, rice bran, and groundnut cake in the ratio of 2 : 1 : 1. A maximum of 9.6 and 8.2 U/mL of enzyme activity was observed in SmF by A. niger CFR 335 and A.ficuum, respectively, when grown in potato dextrose broth.


Asunto(s)
6-Fitasa/biosíntesis , 6-Fitasa/aislamiento & purificación , Aspergillus niger/clasificación , Aspergillus niger/fisiología , Reactores Biológicos/microbiología , Técnicas de Cultivo de Célula/métodos , Proliferación Celular/fisiología , Especificidad de la Especie
11.
Prep Biochem Biotechnol ; 44(2): 193-205, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24152104

RESUMEN

Extracellular phytase from Bacillus licheniformis PFBL-03 was purified in three steps by using ammonium sulfate precipitation, ion-exchange chromatography on a DEAE Sephadex A-50 column, and gel filtration chromatography on Sephadex G-100. The single protein band on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) suggested that the enzyme was homogeneous. The molecular mass determined from SDS-PAGE was 36 kD. The enzyme yield was 10% while the purification fold was 39. The purified phytase exhibited optimum activity at 55°C and was able to retain 55% of its original activity after 60 min of incubation at 80°C. The purified enzyme had optimum pH of 6.0 and was stable over a pH range of 4.0 to 7.5. The kinetic parameters K(m) and V(max) of the purified phytase for sodium phytate were 4.7 mM and 49.01 µmol/min. The activity of the enzyme was enhanced in the presence of Ca²âº but completely inhibited by Fe²âº, Mn²âº, and Cu²âº. The exhibited characteristics of the purified phytase from Bacillus licheniformis PFBL-03 show that the enzyme has potential for applications in the animal feed industry.


Asunto(s)
6-Fitasa/aislamiento & purificación , Bacillus/enzimología , 6-Fitasa/metabolismo , Cromatografía en Gel , Electroforesis en Gel de Poliacrilamida , Estabilidad de Enzimas , Cinética
12.
Mycologia ; 116(4): 477-486, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38819952

RESUMEN

The need for industrially and biotechnologically significant enzymes, such as phytase, is expanding daily as a result of the increased use of these enzymes in a variety of operations, including the manufacture of food, animal feed, and poultry feed. This study sought to characterize purified phytase from A. awamori AFE1 isolated from longhorn beetle for its prospect in industrial applications. Ammonium sulfate precipitation, ion-exchange chromatography, and gel-filtration chromatography were used to purify the crude enzyme obtained from submerged fermentation using phytase-producing media, and its physicochemical characteristics were examined. The homogenous 46.8-kDa phytase showed an 8.1-fold purification and 40.7% recovery. At 70 C and pH 7, the optimum phytase activity was noted. At acidic pH 4-6 and alkaline pH 8-10, it likewise demonstrated relative activity of 88-95% and 67-88%, respectively. It showed 67-70% residual activity between 30 and 70 C after 40 min, and 68-94% residual activity between pH 2 and 12 after 2 h. The presence of Hg+, Mg2+, and Al3+ significantly decreased the enzymatic activity, whereas Ca2+ and Cu2+ enhanced it. Ascorbic acid increased the activity of the purified enzyme, whereas ethylenediaminetetraacetic acid (EDTA) and mercaptoethanol inhibited it. The calculated values for Km and Vmax were 55.4 mM and1.99 µmol/min/mL respectively. A. awamori phytase, which was isolated from a new source, showed unique and remarkable qualities that may find use in industrial operations such as feed pelleting and food processing.


Asunto(s)
6-Fitasa , Aspergillus , Escarabajos , Tracto Gastrointestinal , Animales , 6-Fitasa/metabolismo , 6-Fitasa/aislamiento & purificación , 6-Fitasa/química , Escarabajos/microbiología , Concentración de Iones de Hidrógeno , Aspergillus/enzimología , Aspergillus/metabolismo , Temperatura , Estabilidad de Enzimas , Peso Molecular , Fermentación , Metales/farmacología , Metales/metabolismo
13.
BMC Biotechnol ; 13: 78, 2013 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-24073799

RESUMEN

BACKGROUND: Phytic acid and phytates can interact with biomolecules, such as proteins and carbohydrates, and are anti-nutritional factors found in food and feed. Therefore, it is necessary to remove these compounds in food and feed processing. Phytase can hydrolyze phytic acid and phytates to release a series of lower phosphate esters of myoinositol and orthophosphate. Thus, the purification and characterization of novel phytases that can be used in food and feed processing is of particular interest to the food and feed industries. RESULTS: A novel neutral and heat-tolerant phytase from a newly isolated strain Bacillus nealsonii ZJ0702 was purified to homogeneity with a yield of 5.7% and a purification fold of 44. The molecular weight of the purified phytase obtained by SDS-PAGE was 43 kDa. The homology analysis based on N-terminal amino acid and DNA sequencing indicated that the purified phytase was different from other known phytases. The optimal thermal and pH activity of the phytase was observed at 55°C and 7.5, respectively. Seventy-three percent of the original activity of the phytase was maintained following incubation at 90°C for 10 min. The phytase was stable within a pH range of 6.0-8.0 and showed high substrate specificity for sodium phytate. Cu²âº, Co²âº, Zn²âº, Mn²âº, Ba²âº and Ni²âº ions were found to inhibit the activity of the phytase. CONCLUSIONS: A novel phytase purified from B. nealsonii ZJ0702 was identified. The phytase was found to be thermally stable over a wide temperature range at neutral pH. These properties suggest that this phytase is a suitable alternative to fungal phytases for the hydrolysis of phytic acid and phytates in food and feed processing industries.


Asunto(s)
6-Fitasa/aislamiento & purificación , Bacillus/enzimología , 6-Fitasa/química , Bacillus/clasificación , Electroforesis en Gel de Poliacrilamida , Calor , Concentración de Iones de Hidrógeno , Peso Molecular , Fosfatos/análisis , Ácido Fítico/análisis , Análisis de Secuencia de ADN , Especificidad por Sustrato
14.
Bioorg Khim ; 39(4): 424-9, 2013.
Artículo en Ruso | MEDLINE | ID: mdl-24707723

RESUMEN

For the first time phytase enzyme was isolated from Pantoea vagans 3.2 strain and was subjected to investigation. The enzyme was purified about 474-fold to apparent homogeneity from the crude extract of the strain, its primary structure was determined and it was concluded that phytase of Pantoea vagans 3.2 belongs to the family of histidine acid phosphatases. It has a molecular mass of about 46 kDa and Km for the hydrolysis of sodium phytate was 0.28 mM. Some physicochemical properties ofphytase were investigated.


Asunto(s)
6-Fitasa/química , 6-Fitasa/aislamiento & purificación , Pantoea/enzimología , Secuencia de Aminoácidos , Infecciones por Enterobacteriaceae/enzimología , Infecciones por Enterobacteriaceae/patología , Estabilidad de Enzimas , Hidrólisis , Cinética , Peso Molecular , Pantoea/patogenicidad , Especificidad por Sustrato , Temperatura
15.
Bioorg Khim ; 39(4): 430-6, 2013.
Artículo en Ruso | MEDLINE | ID: mdl-24707724

RESUMEN

Bacillus ginsengihumi phytase has been firstly isolated and studied from the recombinant Escherichia coli strain cellular lysates. The enzyme was obtained from the cellular lysate, purified till homogeneous condition, primary structure was determined. It's concluded that phytase relates to beta-propeller class of phosphatases. The molecular weight of the protein was 41 kDa, pI was 4.8. Some physical and chemical properties of the enzyme were studied.


Asunto(s)
6-Fitasa , Bacillus/enzimología , Escherichia coli/enzimología , 6-Fitasa/química , 6-Fitasa/aislamiento & purificación , Secuencia de Aminoácidos , Estabilidad de Enzimas , Concentración de Iones de Hidrógeno , Especificidad por Sustrato , Temperatura
16.
Protein Expr Purif ; 82(1): 179-85, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22240269

RESUMEN

Cereal purple acid phosphatase-type phytases, PAPhy, play an essential role in making phosphate accessible to mammalian digestion and reducing the environmental impact of manure. Studying the potential of PAPhy requires easy access to the enzymes. For that purpose wheat and barley isophytases have been expressed in Pichia pastoris from constructs encoding the alpha-mating factor at the N-termini and a His6 tag before the stop codon in all constructs. A protein chemical study of a C-terminally truncated recombinant wheat phytase, r-TaPAPhy_b2, was carried out to clarifying the posttranslational processing of proteins secreted from P. pastoris. Extensive mass spectrometric sequencing of tryptic, chymotryptic and AspN derived peptides of both the native and endoH deglycosylated forms showed: (i) All mating factor derived sequence had been removed and further unspecific proteolysis left highly heterogeneous N-terminal variant forms of r-TaPAPhy; (ii) The His6 tag had been retained or slightly truncated; (iii) All seven potential N-glycan sites were glycosylated except for two sites which were partially glycosylated by ca. 90% and 30%; (iv) Among the nine cysteine residues of this phytase, the most N-terminal residue is free, whereas the remaining eight appear to be disulfide bonded. It is noteworthy that already the first step in ESI-MS/MS sequencing had fragmented the hyper glycosylated peptides into free Z, Y and X mass spectrometric glycan fragments attached to the peptide.


Asunto(s)
6-Fitasa/química , 6-Fitasa/genética , Grano Comestible/enzimología , Hordeum/enzimología , Pichia/genética , Triticum/enzimología , 6-Fitasa/aislamiento & purificación , 6-Fitasa/metabolismo , Secuencia de Aminoácidos , Grano Comestible/química , Grano Comestible/genética , Grano Comestible/metabolismo , Expresión Génica , Glicosilación , Hordeum/química , Hordeum/genética , Hordeum/metabolismo , Espectrometría de Masas , Datos de Secuencia Molecular , Pichia/metabolismo , Procesamiento Proteico-Postraduccional , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Alineación de Secuencia , Triticum/química , Triticum/genética , Triticum/metabolismo
17.
Indian J Biochem Biophys ; 49(4): 266-71, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23077788

RESUMEN

Phytases catalyze the release of phosphate from phytic acid. In this study, a phytase producing bacterial strain Shigella sp. CD2 was isolated from the wheat rhizosphere. Phytase production started from the exponential phase of bacterial growth, showing the highest activity during the stationary phase. The enzyme activity was detected in both periplasmic and intracellular fractions. The enzyme was purified by about 133-fold with specific activity 780 U mg(-1) protein. The optimum pH and temperature of the enzyme was 5.5 and 60 degrees C, respectively. The enzyme was thermostable and retained 100% and 75% of its activity on pre-incubation at 70 degrees and 80 degrees C for 30 min, respectively. The Km value for the substrate sodium phytate was 0.25 mM. The enzyme was highly specific to substrate phytate, and no activity was detected in presence of other phosphorylated substrates, such as ATP, ADP, glucose 6-phosphate, fructose 6-phosphate and p-nirophenyl phosphate. The activity declined dramatically in presence of Cu2+, Zn2+ and Fe2+ and SDS, whereas Mg2+ and Co2+ slightly enhanced the enzyme activity. The addition of other metal ions or chemicals had little or no effect on phytase activity. The enzyme was resistant to both pepsin and trypsin. Due to high specific activity, substrate specificity, good pH profile, protease insensitivity and thermostability, phytase encoding gene from Shigella sp. CD2 could be an interesting candidate for industrial applications. Further studies on cloning and expression of Shigella phytase gene are currently in progress.


Asunto(s)
6-Fitasa/aislamiento & purificación , 6-Fitasa/metabolismo , Shigella/enzimología , 6-Fitasa/biosíntesis , Concentración de Iones de Hidrógeno , Pepsina A/metabolismo , Rizosfera , Especificidad por Sustrato , Temperatura , Triticum/microbiología , Tripsina/metabolismo
18.
Indian J Biochem Biophys ; 49(1): 49-54, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22435144

RESUMEN

A novel phytase with a molecular mass of 14 kDa was isolated from fresh fruiting bodies of the common edible mushroom Volvariella volvacea (Straw mushroom). The isolation procedure involved successive chromatography on DEAE-cellulose, CM-cellulose, Affi-gel blue gel, Q-Sepharose and Superdex-75. The enzyme was a monomeric protein and was unadsorbed on DEAE-cellulose, CM-cellulose and Affi-gel blue gel, but was adsorbed on Q-Sepharose. The enzyme was purified 51.6-fold from the crude extract with 25.9% yield. Its N-terminal amino acid sequence GEDNEHDTQA exhibited low homology to the other reported phytases. The optimal pH and temperature of the purified enzyme was 5 and 45 degrees C, respectively. The enzyme was quite stable over the pH range of 3.0 to 9.0 with less than 30% change in its activity, suggesting that it can be used in a very wide pH range. The enzyme exhibited broad substrate selectivity towards various phosphorylated compounds, but lacked antifungal activity against tested plant pathogens.


Asunto(s)
6-Fitasa/química , 6-Fitasa/aislamiento & purificación , Cromatografía DEAE-Celulosa/métodos , Alineación de Secuencia/métodos , Volvariella/enzimología , Adaptación Fisiológica , Estabilidad de Enzimas , Concentración de Iones de Hidrógeno , Peso Molecular , Sefarosa/química , Especificidad por Sustrato , Temperatura , Triazinas/química
19.
J Ind Microbiol Biotechnol ; 38(9): 1407-17, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21184251

RESUMEN

Phytase production by Aspergillus niger NCIM 563 was optimized by using wheat bran in solid state fermentation (SSF). An integrated statistical optimization approach involving the combination of Placket-Burman design (PBD) and Box-Behnken design (BBD) was employed. PBD was used to evaluate the effect of 11 variables related to phytase production, and five statistically significant variables, namely, glucose, dextrin, NaNO(3), distilled water, and MgSO(4) · 7H(2)O, were selected for further optimization studies. The levels of five variables for maximum phytase production were determined by a BBD. Phytase production improved from 50 IU/g dry moldy bran (DMB) to 154 IU/g DMB indicating 3.08-fold increase after optimization. A simultaneous reduction in fermentation time from 7 to 4 days shows a high productivity of 38,500 IU/kg/day. Scaling up the process in trays gave reproducible phytase production overcoming industrial constraints of practicability and economics. The culture extract also had 133.2, 41.58, and 310.34 IU/g DMB of xylanase, cellulase, and amylase activities, respectively. The partially purified phytase was optimally active at 55°C and pH 6.0. The enzyme retained ca. 75% activity over a wide pH range 2.0-9.5. It also released more inorganic phosphorus from soybean meal in a broad pH range from 2.5 to 6.5 under emulated gastric conditions. Molecular weight of phytase on Sephacryl S-200 was approximately 87 kDa. The K (m) and V (max) observed were 0.156 mM and 220 µm/min/mg. The SSF phytase from A. niger NCIM 563 offers an economical production capability and its wide pH stability shows its suitability for use in poultry feed.


Asunto(s)
6-Fitasa/biosíntesis , Aspergillus niger/enzimología , 6-Fitasa/aislamiento & purificación , 6-Fitasa/metabolismo , Animales , Medios de Cultivo/química , Fibras de la Dieta/microbiología , Fermentación
20.
Protein Expr Purif ; 74(2): 196-203, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20655385

RESUMEN

Phytases catalyze the sequential hydrolysis of phytic acid (myo-insositol hexakisphosphate), the most abundant inositol phosphate in cells. Phytic acid constitutes 3-5% of the dry weight of cereal grains and legumes such as corn and soybean. The high concentration of phytates in animal feed and the inability of non-ruminant animals such as swine and poultry to digest phytates leads to phosphate contamination of soil and water bodies. The supplementation of animal feed with phytases results in increased bioavailability to animals and decreased environmental contamination. Therefore, phytases are of great commercial importance. Phytases with a range of properties are needed to address the specific digestive needs of different animals. Alkaline phytase (LlALP1 and LlALP2) which possess unique catalytic properties that have the potential to be useful as feed and food supplement has been identified in lily pollen. Substantial quantities of alkaline phytase are needed for animal feed studies. In this paper, we report the heterologous expression of LlALP2 from lily pollen in Pichia pastoris. The expression of recombinant LlALP2 (rLlALP2) was optimized by varying the cDNA coding for LlALP2, host strain and growth conditions. The catalytic properties of recombinant LlALP2 were investigated extensively (substrate specificity, pH- and temperature dependence, and the effect of Ca(2+), EDTA and inhibitors) and found to be very similar to that of the native LlALP2 indicating that rLlALP2 from P. pastoris can serve as a potential source for structural and animal feed studies.


Asunto(s)
6-Fitasa/genética , Lilium/enzimología , Pichia/genética , 6-Fitasa/química , 6-Fitasa/aislamiento & purificación , Vectores Genéticos/metabolismo , Ácido Fítico/metabolismo , Pichia/citología , Pichia/metabolismo , Polen/enzimología , Pliegue de Proteína
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