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1.
Biomed Res Int ; 2024: 2222098, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39015602

RESUMEN

In this study, we aimed to isolate and purify catalase from human blood erythrocytes by using a newly synthesized affinity gel. The synthesized ω-amino hexyl agarose-1,2,3-triazole-5-carboxylic acid affinity gel was analyzed by FT-IR. Then, different buffer, pH, and ionic strength parameters were optimized to determine the equilibration, washing, and elution buffer conditions. The catalase was purified from human blood erythrocytes with a specific activity of 45.58 EU/mg, purification fold of 529.50, and a yield of 0.416% using the synthesized new affinity gel. The purity and molecular weight of the enzyme were analyzed by SDS-PAGE, and a single band at 60 kDa was observed for catalase. The optimum reaction temperature of the catalase was found to be 30°C, while the thermal stability temperature was 60°C. The Km and Vmax of the enzyme for hydrogen peroxide were calculated at 0.125 mM and 2500 U mL-1, respectively.


Asunto(s)
Catalasa , Cromatografía de Afinidad , Eritrocitos , Humanos , Catalasa/química , Catalasa/aislamiento & purificación , Catalasa/metabolismo , Eritrocitos/enzimología , Cromatografía de Afinidad/métodos , Concentración de Iones de Hidrógeno , Temperatura , Estabilidad de Enzimas , Cinética , Peróxido de Hidrógeno/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Peso Molecular
2.
Int J Biol Macromol ; 172: 418-428, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33460658

RESUMEN

The major antioxidant enzyme catalase is downregulated and the enzyme activity is compromised in various disease conditions such as malarial and cancer. Hence, the restoration and protection of catalase is a promising therapeutic strategy in disease management. In the present study, for the first time we have demonstrated the protective role of well-known anti-malarial drug Artemisinin (ART) on the time and temperature-induced degradation of bovine liver catalase (BLC) activity. The findings at different time intervals and at higher temperature showed the protective role of ART on BLC activity. Molecular docking studies suggested specific binding of ART on BLC through heme group interface which was further supported by cyclic voltammetry and dynamic light scattering study. The stabilization of BLC in presence of ART was mediated through forming a BLC-ART complex with reduced and shifted electrochemical peak and increased hydrodynamic diameter. ART substantially prevents the temperature-induced reduction in α-helical content with simultaneous increment in other secondary structures like antiparallel, parallel, ß-turn and random coils. Nevertheless, the protective role of ART was accepted from the enhanced thermal stability and increased Tm value of BLC in presence of ART at higher temperatures. Our results uncover the mechanism of interaction between ART with BLC and suggest the protective role of ART towards spatiotemporal alteration of BLC by preventing the structural and molecular change in BLC. Thus, the findings advocate ART as a potential therapeutic drug for diseases associated with reduced catalase activity.


Asunto(s)
Antioxidantes/química , Artemisininas/química , Catalasa/química , Animales , Antioxidantes/metabolismo , Artemisininas/metabolismo , Catalasa/aislamiento & purificación , Catalasa/metabolismo , Dominio Catalítico , Bovinos , Humanos , Enlace de Hidrógeno , Hígado/química , Hígado/enzimología , Simulación del Acoplamiento Molecular , Unión Proteica , Conformación Proteica en Hélice alfa , Conformación Proteica en Lámina beta , Dominios y Motivos de Interacción de Proteínas , Estructura Terciaria de Proteína , Termodinámica
3.
Jpn J Infect Dis ; 74(3): 214-219, 2021 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-33132303

RESUMEN

Despite the availability of anti-tuberculosis drugs, the treatment of tuberculosis has been complicated by drug-resistant tuberculosis. The early detection of drug resistance makes early treatment possible. However, the available tools are mainly for rifampicin resistance detection, and the existing isoniazid resistance detection method is expensive, highly technical, and complicated, making it unsustainable for use in developing nations. This study aimed to develop a simple, rapid, and low-cost diagnostic kit for isoniazid-resistant tuberculosis using the single-stranded tag hybridization method to target an isoniazid resistance-conferring mutation. Specificity and sensitivity were assessed using DNA extracted from 49 isoniazid-resistant and 41 isoniazid-susceptible Mycobacterium tuberculosis clinical isolates cultured in mycobacterial growth indicator tubes. Positive signals were observed on mutant and wild-type lines with 100% sensitivity and specificity compared with Sanger sequencing results. In contrast, no positive signal was observed for non-tuberculosis mycobacteria. The detection limit of this method was 103 CFU or less. The STH-PAS system for isoniazid-resistant M. tuberculosis detection developed in this study offers a better alternative to conventional phenotypic isoniazid resistance determination, which will be of both clinical and epidemiological significance in resource-limited nations.


Asunto(s)
Proteínas Bacterianas/aislamiento & purificación , Catalasa/aislamiento & purificación , Cromatografía/métodos , Isoniazida/aislamiento & purificación , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/aislamiento & purificación , Tuberculosis Resistente a Múltiples Medicamentos/diagnóstico , Antituberculosos/farmacología , ADN Bacteriano , Humanos , Isoniazida/farmacología , Mycobacterium tuberculosis/efectos de los fármacos , Sensibilidad y Especificidad , Análisis de Secuencia , Tuberculosis Resistente a Múltiples Medicamentos/genética
4.
Sheng Wu Gong Cheng Xue Bao ; 36(8): 1568-1577, 2020 Aug 25.
Artículo en Chino | MEDLINE | ID: mdl-32924355

RESUMEN

Catalase catalyzes the decomposition of H2O2 to H2O and O2, and has a wide range of industrial applications. However, most catalases used in the textile and paper industries are often subjected to high-alkaline challenges which makes it necessary to develop alkaline catalase. In this study, a catalase from Corynebacterium glutamicum was expressed in Escherichia coli, and the expression conditions were optimized. The recombinant catalase was purified by Ni-chelating affinity chromatography, and the recombinant enzyme was characterized. The optimal conditions of producing the recombinant catalase were: an IPTG concentration of 0.2 mmol/L, a culturing temperature of 25 °C and a culturing time of 11 h. The purified catalase had a specific activity of 55 266 U/mg, and it had a high activity in the pH range of 4.0 to11.5, with the highest activity at pH 11.0. When treated in pH 11.0 for 3 h, the enzyme retained 93% of its activity, indicating that the enzyme was qualified with a favorable stability under high-alkaline condition. The recombinant catalase had maximal activity at 30 °C, and showed a satisfactory thermal stability at a range of 25 °C to 50 °C. The apparent Km and Vmax values of purified catalase were 25.89 mmol/L and 185.18 mmol/(minmg), respectively. Besides, different inhibitors, such as sodium dodecyl sulfate (SDS), urea, NaN2, ß-mercaptoethanol, and EDTA had different degrees of inhibition on enzyme activity. The catalase from C. glutamicum shows high catalytic efficiency and high alkaline stability, suggesting its potential utilization in industrial production.


Asunto(s)
Catalasa , Corynebacterium glutamicum , Regulación Enzimológica de la Expresión Génica , Catalasa/genética , Catalasa/aislamiento & purificación , Catalasa/metabolismo , Corynebacterium glutamicum/enzimología , Activación Enzimática , Estabilidad de Enzimas , Concentración de Iones de Hidrógeno
5.
FEBS J ; 287(20): 4525-4539, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32037677

RESUMEN

The polyextremophilic strain Acinetobacter sp. Ver3 isolated from high-altitude Andean lakes exhibits elevated tolerance to UV-B radiation and to pro-oxidants, a feature that has been correlated to its unusually high catalase activity. The Ver3 genome sequence analysis revealed the presence of two genes coding for monofunctional catalases: AV3 KatE1 and AV3 KatE2, the latter harboring an N-terminal signal peptide. We show herein that AV3 KatE1 displays one of the highest catalytic activities reported so far and is constitutively expressed at relatively high amounts in the cytosol, acting as the main protecting catalase against H2 O2 and UV-B radiation. The second catalase, AV3 KatE2, is a periplasmic enzyme strongly induced by both peroxide and UV, conferring supplementary protection against pro-oxidants. The N-terminal signal present in AV3 KatE2 was required not only for transport to the periplasm via the twin-arginine translocation pathway, but also for proper folding and subsequent catalytic activity. The analysis of catalase distribution among 114 Acinetobacter complete genomes revealed a great variability in the catalase classes, with A. baumannii clinical isolates exhibiting higher numbers of isoenzymes and the most variable profiles.


Asunto(s)
Acinetobacter/enzimología , Antioxidantes/metabolismo , Catalasa/metabolismo , Peróxido de Hidrógeno/farmacología , Rayos Ultravioleta , Antioxidantes/aislamiento & purificación , Biocatálisis , Catalasa/genética , Catalasa/aislamiento & purificación
6.
Indian J Med Res ; 150(1): 33-42, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31571627

RESUMEN

Background & objectives: Rapid detection of drug resistance in Mycobacterium tuberculosis (MTB) is essential for the efficient control of tuberculosis. Hence, in this study a nested-allele-specific (NAS) PCR, nested multiple allele-specific PCR (NMAS-PCR) and multiple allele-specific (MAS) PCR assays were evaluated that enabled detection of the most common mutations responsible for isoniazid (INH) and rifampicin (RIF) resistance in MTB isolates directly from clinical specimens. Methods: Six pairs of primers, mutated and wild type, were used for the six targets such as codon 516, 526 and 531 of rpoB, codon 315 of katG and C15-T substitution in the promoter region of mabA-inhA using allele-specific (AS) PCR assays (NAS-PCR, NMAS-PCR and MAS-PCR). The performance of AS PCR method was compared with phenotypic drug susceptibility testing (DST). Results: The usefulness of AS PCR assays was evaluated with 391 clinical specimens (251 Acid fast bacilli smear positive and MTB culture positive; 93 smear negative and MTB culture positive; 47 smear positive and MTB culture negative) and 344 MTB culture positive isolates. With culture-based phenotypic DST as a reference standard, the sensitivity and specificity of the NAS-PCR, NMAS-PCR and MAS-PCR assay for drug resistance-related genetic mutation detection were 98.6 and 97.8 per cent for INH, 97.5 and 97.9 per cent for RIF and 98.9 and 100 per cent for multidrug resistance (MDR). Interpretation & conclusions: The performance of AS PCR assays showed that those could be less expensive and technically executable methods for rapid detection of MDR-TB directly from clinical specimens.


Asunto(s)
Farmacorresistencia Bacteriana Múltiple/genética , Reacción en Cadena de la Polimerasa Multiplex , Mycobacterium tuberculosis/aislamiento & purificación , Tuberculosis Resistente a Múltiples Medicamentos/diagnóstico , Alelos , Antituberculosos/uso terapéutico , Proteínas Bacterianas/genética , Proteínas Bacterianas/aislamiento & purificación , Catalasa/genética , Catalasa/aislamiento & purificación , ARN Polimerasas Dirigidas por ADN/genética , ARN Polimerasas Dirigidas por ADN/aislamiento & purificación , Femenino , Humanos , Isoniazida/efectos adversos , Isoniazida/uso terapéutico , Masculino , Mutación , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/patogenicidad , Oxidorreductasas/genética , Oxidorreductasas/aislamiento & purificación , Rifampin/efectos adversos , Rifampin/uso terapéutico , Esputo/microbiología , Tuberculosis Resistente a Múltiples Medicamentos/genética , Tuberculosis Resistente a Múltiples Medicamentos/microbiología
7.
PLoS One ; 14(7): e0219300, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31291312

RESUMEN

Terfezia claveryi Chatin is a mycorrhizal fungus that forms ectendomycorrhizal associations with plants of Helianthemum genus. Its appreciated edibility and drought resistance make this fungus a potential alternative crop in arid and semiarid areas of the Mediterranean region. In order to increase the knowledge about the biology of this fungus in terms of mycorrhiza formation and response to drought stress, a catalase from T. claveryi (TcCAT-1) has been purified to apparent homogeneity and biochemically characterized; in addition, the expression pattern of this enzyme during different stages of T. claveryi biological cycle and under drought stress conditions are reported. The results obtained, together with the phylogenetic analysis and homology modeling, indicate that TcCAT-1 is a homotetramer large subunit size monofunctional-heme catalase belonging to Clade 2. The highest expression of this enzyme occurs in mature mycorrhiza, revealing a possible role in mycorrhiza colonization, but it is not upregulated under drought stress. However, the H2O2 content of mycorrhizal plants submitted to drought stress is lower than in well watered treatments, suggesting that mycorrhization improves the plant's oxidative stress response, although not via TcCAT-1 upregulation.


Asunto(s)
Catalasa/química , Cistaceae/microbiología , Micorrizas/enzimología , Simbiosis/genética , Catalasa/aislamiento & purificación , Cistaceae/crecimiento & desarrollo , Sequías , Regulación Enzimológica de la Expresión Génica , Peróxido de Hidrógeno/química , Micelio/enzimología , Filogenia
8.
Prep Biochem Biotechnol ; 49(4): 391-399, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30767698

RESUMEN

Aqueous two-phase partitioning system (ATPS) was used to extract and purify catalase from Bacillus pumilus. The system parameters for effective purification of catalase were optimized. The best catalase recovery (123%) with a 4.6-fold purification was obtained in the bottom phase of ATPS including the mixture of 15% (w/w) PEG4000, 10% (w/w) Na2SO4 and 3% (w/w) NaCl at pH 5.0. The purified enzyme was characterized regarding its activity and stability. The highest enzyme activity was observed at pH 7.0 and 37 °C on hydrogen peroxide. The enzyme was quite stable at temperatures between 30 and 55 °C and a pH range of 7.0-9.0. The Km and Vmax values were determined from Lineweaver-Burk plot as 11 mM and 1667 µmole ml-1 min-1, respectively. Overall, it can be said that ATPS is a rapid, reasonable, straightforward and cost-effective process for catalase purification in comparison to the chromatographic methods.


Asunto(s)
Bacillus pumilus/enzimología , Catalasa/química , Polietilenglicoles/química , Extracción en Fase Sólida/métodos , Sulfatos/química , Catalasa/aislamiento & purificación , Estabilidad de Enzimas , Concentración de Iones de Hidrógeno , Peso Molecular , Temperatura , Agua/química
9.
Biomed Res Int ; 2019: 2014347, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30756080

RESUMEN

The study aimed to determine the suitability of testing the saliva of kickboxing athletes to show changes in biochemical parameters in dynamic of training. 8 elite male athletes (mean age 17.29± 0.31 years, body mass 66.82± 3.46kg, with 5.62±0.96 years of training experience) participated in the study. Indicators of lipid peroxidation and glycolysis (the concentration of lactic acid and pyruvic acid) were defined before and after a training session. Significant increases in indicators of lipid peroxidation activity indicators and the concentration of lactic acid (4-fold) were observed; analysis of correlation matrices confirms the absence of expressed changes. At the same time, significant decreases in catalase (10-fold from 3.69 µkat/L to 0.39 µkat/L) and pyruvic acid (from 3.92 µl/l to 0.55 µl/l) were observed. Our results confirm the value of using saliva to determine training load in an individual. Moreover, the study provided information on the importance of indexes reflecting a correlation of various biochemical indicators to estimate the sufficiency of training loads. The ease of sampling and informational content of saliva are reasons to use such tests in monitoring athletes' functional state to prevent fatigue.


Asunto(s)
Atletas , Fatiga/metabolismo , Ácido Láctico/metabolismo , Saliva/química , Adolescente , Adulto , Rendimiento Atlético , Catalasa/aislamiento & purificación , Catalasa/metabolismo , Fatiga/patología , Fatiga/prevención & control , Glucólisis/genética , Humanos , Ácido Láctico/aislamiento & purificación , Peroxidación de Lípido/genética , Masculino , Ácido Pirúvico/aislamiento & purificación , Ácido Pirúvico/metabolismo , Saliva/metabolismo , Adulto Joven
10.
Colloids Surf B Biointerfaces ; 173: 58-68, 2019 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-30266021

RESUMEN

The cross-linked enzyme aggregates (CLEAs) have numerous economic advantages in the industrial bio catalysis. In the present study, the multi CLEAs containing protease, catalase, and lipase from the sunflower seeds using starch as a cofeeder as well as bovine serum albumin (BSA) are designed and prepared successfully. After optimization, multi CLEAs of enzyme have been prepared with ammonium sulfate (55% w/v), glutaraldehyde (100 mM), and 8 mg/mL of starch or 20 mg/mL of BSA. The activity recovery of protease, catalase, and lipase multi CLEAs-starch are 87, 61, and 60%, respectively. Whereas, CLEAs prepared with BSA are 74, 61, and 50% activity and multi CLEAs only 60, 44, and 41% of protease, catalase, and lipase, respectively. The multi CLEAs were used to catalyze the reactions for enhanced washing process. After adding multi CLEAs-starch, the stain removal percentage of detergents is enhanced by 83%.The present study reports a high stability, simplicity, low cost, and recyclability of the novel multi CLEAs from the sunflower seeds that make them efficient as a highly active biocatalysts in the biotechnological applications. We believe that these novel multi CLEAs present a new approach to the synthesis of multi enzyme biocatalysts from the cheap and friendly environmental sources.


Asunto(s)
Catalasa/química , Helianthus/química , Lipasa/química , Péptido Hidrolasas/química , Proteínas de Plantas/química , Semillas/química , Sulfato de Amonio/química , Biocatálisis , Catalasa/aislamiento & purificación , Colorantes/aislamiento & purificación , Reactivos de Enlaces Cruzados/química , Detergentes/química , Pruebas de Enzimas , Glutaral/química , Helianthus/enzimología , Cinética , Lipasa/aislamiento & purificación , Péptido Hidrolasas/aislamiento & purificación , Proteínas de Plantas/aislamiento & purificación , Agregado de Proteínas , Semillas/enzimología , Albúmina Sérica Bovina/química , Almidón/química
11.
J Phys Chem B ; 122(11): 2881-2890, 2018 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-29470911

RESUMEN

Broken symmetry density functional theory has been used to calculate g-tensor, 55Mn, 14N, and 17O hyperfine couplings for active site models of superoxidized MnIII/MnIV manganese catalase both in its native and azide-inhibited form. While a good agreement is found between the calculated and experimental g-tensor and 55Mn hyperfine couplings for all models, the active site geometry and Mn ion oxidation state can only be readily distinguished based on a comparison of the calculated and experimental 14N azide and 17O HFCs. This comparison shows that only models containing a Jahn-Teller distorted 5-coordinate (MnIII)2 site and a 6-coordinate (MnIV)1 site can satisfactorily reproduce the experimental 14N and 17O hyperfine couplings.


Asunto(s)
Catalasa/metabolismo , Espectroscopía de Resonancia por Spin del Electrón , Manganeso/metabolismo , Teoría Cuántica , Superóxidos/metabolismo , Sitios de Unión , Catalasa/química , Catalasa/aislamiento & purificación , Lactobacillus plantarum/enzimología , Manganeso/química , Modelos Moleculares , Superóxidos/química , Thermus thermophilus/enzimología
12.
Appl Biochem Biotechnol ; 185(3): 717-735, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29299755

RESUMEN

Human catalase cDNA was cloned into a pEX-C-His vector. Purified recombinant catalase was immobilized on nanoparticles. Gold and silver nanoparticles were synthesized in a variety of sizes by chemical reduction; no agglomerates or aggregates were observed in any of the colloids during dynamic light scattering or scanning transmission electron microscopy analysis. After immobilization on gold nanoparticles, recombinant catalase activity was found to be lower than that of the same amount of enzyme in aqueous solution. However, after 10 days of storage at room temperature, the activity of catalase immobilized on gold nanoparticles (AuNPs) of 13 and 20 nm and coverage of 133% was 68 and 83% greater than catalase in aqueous solution, respectively. During 10 days of experiment, percentage activity of catalase immobilized on those gold nanoparticles was higher in comparison to CAT in aqueous solution. Catalase immobilized on silver nanoparticles did not lose activity as significantly as catalase immobilized on AuNPs. Those results confirm the ability to produce recombinant human enzymes in a bacterial expression system and its potential use while immobilized on silver or gold nanoparticles.


Asunto(s)
Catalasa/metabolismo , Enzimas Inmovilizadas/metabolismo , Oro/química , Nanopartículas del Metal/química , Plata/química , Western Blotting , Catalasa/aislamiento & purificación , Electroforesis en Gel de Poliacrilamida , Enzimas Inmovilizadas/genética , Enzimas Inmovilizadas/aislamiento & purificación , Escherichia coli/genética , Humanos , Luz , Microscopía Electrónica de Transmisión de Rastreo , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Dispersión de Radiación , Soluciones , Propiedades de Superficie , Agua
13.
J Proteomics ; 175: 87-94, 2018 03 20.
Artículo en Inglés | MEDLINE | ID: mdl-29331514

RESUMEN

Diagnostic reagents based on food allergen extracts often lack sufficient sensitivity. The introduction of well characterized food allergens in molecular allergy diagnosis has been recognized as valid approach to circumvent unstandardized allergen extracts. Banana fruit (Musa acuminata) is a well-established allergen source which besides six characterized allergens, contains unidentified IgE reactive proteins whose clinical relevance remains undefined. By employment of a combinatorial peptide ligand library (CPLL) methodology with 2-D PAGE, mass spectrometric and 2-D immunoblot analysis, a novel allergen from banana fruit was detected in banana as catalase. A recombinant homologue of natural catalase was produced, isolated and biochemically characterized. The recombinant protein showed IgE reactivity in 7 out of 13 tested patients with suspected allergy to banana in immunoblot. Novel banana fruit allergens should be added as components to allergen-microarrays for the diagnosis and the monitoring of banana allergy. SIGNIFICANCE: By employment of CPLL methodology with 2-D PAGE, mass spectrometric and 2-D immunoblot analysis catalase from banana fruit is identified as a novel allergen, with proposed designation as Mus a 7. IgE reactive recombinant Mus a 7 was produced and should be included in a component-resolved allergy diagnosis.


Asunto(s)
Western Blotting/métodos , Catalasa/aislamiento & purificación , Hipersensibilidad a los Alimentos/etiología , Musa/inmunología , Proteómica/métodos , Alérgenos/análisis , Catalasa/análisis , Hipersensibilidad a los Alimentos/diagnóstico , Frutas/enzimología , Frutas/inmunología , Humanos , Inmunoglobulina E/inmunología , Musa/enzimología , Proteínas de Plantas/análisis , Proteínas de Plantas/inmunología
14.
Artículo en Inglés | MEDLINE | ID: mdl-29100758

RESUMEN

Climate change and increasing temperatures are global concerns. Camel (Camelus dromedarius) lives most of its life under high environmental stress in the desert and represent ideal model for studying desert adaptation among mammals. Catalase plays a key role in protecting cells against oxidative stress. For the first time, catalase from camel liver was purified to homogeneity by zinc chelate affinity chromatography using pH gradient elution, a better separation was obtained. A purification fold of 201.81 with 1.17% yield and a high specific activity of 1132539.37U/mg were obtained. The native enzyme had a molecular weight of 268kDa and was composed of four subunits of equal size (65kDa). The enzyme showed optimal activity at a temperature of 45°C and pH 7.2. Thiol reagents, ß-Mercaptoethanol and D,L-Dithiothreitol, inhibited the enzyme activity. The enzyme was inhibited by Al3+, Cd2+ and Mg2+, whereas Ca2+, Co2+ and Ni2+ stimulated the catalase activity. Reduced glutathione has no effect on catalase activity. The Km and Vmax of the enzyme for hydrogen peroxide were 37.31mM and 6185157U/mg, respectively. Sodium azide inhibited the enzyme noncompetitively with Ki value of 14.43µM, the IC50 was found to be 16.71µM. The properties of camel catalase were different comparing to those of mammalian species. Relatively higher molecular weight, higher optimum temperature, protection of reduced glutathione from hydrogen peroxide oxidation and higher affinity for hydrogen peroxide and sodium azide, these could be explained by the fact that camel is able to live in the intense environmental stress in the desert.


Asunto(s)
Catalasa/química , Catalasa/aislamiento & purificación , Cromatografía de Afinidad/métodos , Hígado/enzimología , Animales , Camelus , Catalasa/antagonistas & inhibidores , Catalasa/metabolismo , Ácido Edético , Inhibidores Enzimáticos , Concentración de Iones de Hidrógeno , Dodecil Sulfato de Sodio , Temperatura
15.
Electron. j. biotechnol ; 30: 110-117, nov. 2017. graf, tab, ilus
Artículo en Inglés | LILACS | ID: biblio-1021571

RESUMEN

Background: Catalase (CAT) is an important enzyme that degrades H2O2 into H2O and O2. To obtain an efficient catalase, in this study, a new strain of high catalase-producing Serratia marcescens, named FZSF01, was screened and its catalase was purified and characterized. Results: After optimization of fermentation conditions, the yield of catalase produced by this strain was as high as 51,468 U/ml. This catalase was further purified using two steps: DEAE-fast flow and Sephedex-G150. The purified catalase showed a specific activity of 197,575 U/mg with a molecular mass of 58 kDa. This catalase exhibited high activity at 20­70°C and pH 5.0­11.0. Km of the catalase was approximately 68 mM, and Vmax was 1886.8 mol/min mg. This catalase was further identified by LC­MS/MS, and the encoding gene was cloned and expressed in Escherichia coli BL21 (DE3) with a production of 17,267 ± 2037 U/ml. Conclusions: To our knowledge, these results represent one of the highest fermentation levels reported among current catalase-producing strains. This FZSF01 catalase may be suitable for several industrial applications that comprise exposure to alkaline conditions and under a wide range of temperatures.


Asunto(s)
Serratia marcescens/enzimología , Catalasa/metabolismo , Recombinación Genética , Serratia marcescens/genética , ARN Ribosómico 16S , Cinética , Catalasa/aislamiento & purificación , Catalasa/genética , Cromatografía Liquida , Análisis de Secuencia de ADN , Electroforesis , Escherichia coli/genética , Escherichia coli/metabolismo , Fermentación , Peróxido de Hidrógeno/metabolismo
16.
Acta Biochim Pol ; 64(3): 543-549, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28892106

RESUMEN

Vibrio vulnificus is a virulent human pathogen causing gastroenteritis and possibly life threatening septicemia in patients. Most V. vulnificus are catalase positive and can deactivate peroxides, thus allowing them to survive within the host. In the study presented here, a catalase from V. vulnificus (CAT-Vv) was purified to homogeneity after expression in Escherichia coli. The kinetics and function of CAT-Vv were examined. CAT-Vv catalyzed the reduction of H2O2 at an optimal pH of 7.5 and temperature of 35°C. The Vmax and Km values were 65.8±1.2 U/mg and 10.5±0.7 mM for H2O2, respectively. Mutational analysis suggests that amino acids involved in heme binding play a key role in the catalysis. Quantitative reverse transcription-PCR revealed that in V. vulnificus, transcription of CAT-Vv was upregulated by low salinity, heat, and oxidative stresses. This research gives new clues to help inhibit the growth of, and infection by V. vulnificus.


Asunto(s)
Catalasa/genética , Catalasa/metabolismo , Vibrio vulnificus/enzimología , Catalasa/aislamiento & purificación , Cromatografía de Afinidad , Clonación Molecular , Simulación por Computador , Estabilidad de Enzimas , Regulación Bacteriana de la Expresión Génica , Hemo/metabolismo , Concentración de Iones de Hidrógeno , Mutagénesis Sitio-Dirigida , Filogenia , Ingeniería de Proteínas/métodos , Proteínas Recombinantes/genética , Temperatura , Vibrio vulnificus/fisiología
17.
Biomed Res Int ; 2017: 6847532, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28638833

RESUMEN

As an indicator of the antioxidant capability of plants, catalase can detoxify reactive oxygen species (ROS) generated by environmental stresses. Sweet potato is one of the top six most important crops in the world. However, its catalases remain largely unknown. In this study, a catalase encoding gene, IbCAT2 (accession number: KY615708), was identified and cloned from sweet potato cv. Xushu 18. It contained a 1479 nucleotides' open reading frame (ORF). S-R-L, Q-K-L, and a putative calmodulin binding domain were located at the C-terminus of IbCAT2, which suggests that IbCAT2 could be a peroxisomal catalase. Next-generation sequencing (NGS) based quantitative analyses showed that IbCAT2 was mainly expressed in young leaves and expanding tuberous roots under normal conditions. When exposed to 10% PEG6000 or 200 mmol/L NaCl solutions, IbCAT2 was upregulated rapidly in the first 11 days and then downregulated, although different tissues showed different degree of change. Overexpression of IbCAT2 conferred salt and drought tolerance in Escherichia coli and Saccharomyces cerevisiae. The positive response of IbCAT2 to abiotic stresses suggested that IbCAT2 might play an important role in stress responses.


Asunto(s)
Catalasa , Ipomoea batatas , Proteínas de Plantas , Estrés Fisiológico , Catalasa/química , Catalasa/genética , Catalasa/aislamiento & purificación , Catalasa/metabolismo , Regulación Enzimológica de la Expresión Génica/fisiología , Regulación de la Expresión Génica de las Plantas/fisiología , Ipomoea batatas/enzimología , Ipomoea batatas/genética , Sistemas de Lectura Abierta , Hojas de la Planta/enzimología , Hojas de la Planta/genética , Proteínas de Plantas/genética , Proteínas de Plantas/aislamiento & purificación , Proteínas de Plantas/metabolismo , Tubérculos de la Planta/enzimología , Tubérculos de la Planta/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Análisis de Secuencia de ADN
18.
Int J Biol Macromol ; 103: 89-98, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28501604

RESUMEN

A catalase-producing thermophilic bacterium, Ureibacillus thermosphaericus FZSF03, was isolated from high-temperature compost. Catalase production in this strain increased 31 times and reached 57,630U/mL after optimization in a shake flask, which might represent the highest catalase activity level among reported wild strains. This catalase was further purified and identified. The purified enzyme showed a specific activity of 219,360U/mg, higher than many other catalases. The molecular weight of this enzyme is 52kDa according to sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), and the enzyme was identified as a monofunctional haeme catalase of Ureibacillus thermosphaericus by liquid chromatography-mass spectrometry (LC-MS)/MS. The optimal reaction temperature for this catalase was found to be 60°C. Stability was observed at 60°C and at a pH of 10.0, indicating the superiority of this enzyme at a high temperature and under alkaline conditions. Therefore, this catalase is a prospective candidate for industrial production and applications. The gene encoding this catalase is 1503bp. As the amino acid sequence shows low similarity with other catalases, we suggest that this is a novel monofunctional haeme catalase.


Asunto(s)
Bacillales/enzimología , Catalasa/biosíntesis , Catalasa/genética , Temperatura , Secuencia de Aminoácidos , Bacillales/efectos de los fármacos , Bacillales/genética , Bacillales/fisiología , Carbono/farmacología , Catalasa/aislamiento & purificación , Catalasa/metabolismo , Clonación Molecular , Relación Dosis-Respuesta a Droga , Fermentación/efectos de los fármacos , Concentración de Iones de Hidrógeno , Cinética , Nitrógeno/farmacología
19.
J Mol Recognit ; 30(8)2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28295815

RESUMEN

Nowadays, understanding of interface between protein and drugs has become an active research area of interest. These types of interactions provide structural guidelines in drug design with greater clinical efficacy. Thus, structural changes in catalase induced by clofazimine were monitored by various biophysical techniques including UV-visible spectrometer, fluorescence spectroscopy, circular dichroism, and dynamic light scattering techniques. Increase in absorption spectra (UV-visible spectrum) confers the complex formation between drug and protein. Fluorescence quenching with a binding constants of 2.47 × 104  M-1 revealed that clofazimine binds with protein. Using fluorescence resonance energy transfer, the distance (r) between the protein (donor) and drug (acceptor) was found to be 2.89 nm. Negative Gibbs free energy change (ΔG°) revealed that binding process is spontaneous. In addition, an increase in α-helicity was observed by far-UV circular dichroism spectra by adding clofazimine to protein. Dynamic light scattering results indicate that topology of bovine liver catalase was slightly altered in the presence of clofazimine. Hydrophobic interactions are the main forces between clofazimine and catalase interaction as depicted by molecular docking studies. Apart from hydrophobic interactions, some hydrogen bonding was also observed during docking method. The results obtained from the present study may establish abundant in optimizing the properties of ligand-protein mixtures relevant for numerous formulations.


Asunto(s)
Catalasa/química , Clofazimina/química , Hígado/química , Simulación del Acoplamiento Molecular , Animales , Sitios de Unión , Catalasa/aislamiento & purificación , Bovinos , Cristalografía por Rayos X , Enlace de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Hígado/enzimología , Unión Proteica , Conformación Proteica en Hélice alfa , Conformación Proteica en Lámina beta , Dominios y Motivos de Interacción de Proteínas , Análisis Espectral/métodos , Termodinámica
20.
Biosens Bioelectron ; 93: 9-13, 2017 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-28073620

RESUMEN

A skin covered oxygen electrode, SCOE, was constructed with the aim to study the enzyme catalase, which is part of the biological antioxidative system present in skin. The electrode was exposed to different concentrations of H2O2 and the amperometric current response was recorded. The observed current is due to H2O2 penetration through the outermost skin barrier (referred to as the stratum corneum, SC) and subsequent catalytic generation of O2 by catalase present in the underlying viable epidermis and dermis. By tape-stripping the outermost skin layers we demonstrate that SC is a considerable diffusion barrier for H2O2 penetration. Our experiments also indicate that skin contains a substantial amount of catalase, which is sufficient to detoxify H2O2 that reaches the viable epidermis after exposure of skin to high concentrations of peroxide (0.5-1mM H2O2). Further, we demonstrate that the catalase activity is reduced at acidic pH, as compared with the activity at pH 7.4. Finally, experiments with often used penetration enhancer thymol shows that this compound interferes with the catalase reaction. Health aspect of this is briefly discussed. Summarizing, the results of this work show that the SCOE can be utilized to study a broad spectrum of issues involving the function of skin catalase in particular, and the native biological antioxidative system in skin in general.


Asunto(s)
Técnicas Biosensibles , Catalasa/aislamiento & purificación , Epidermis/enzimología , Piel/enzimología , Antioxidantes/metabolismo , Catalasa/química , Catálisis , Electrodos , Epidermis/química , Humanos , Peróxido de Hidrógeno/química , Concentración de Iones de Hidrógeno , Oxígeno/metabolismo
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