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Sample records for excelsa catalase activity

  1. Antibacterial activity of chrysophanol isolated from Aloe excelsa ...

    African Journals Online (AJOL)

    Extraction of the yellow colour compounds of leaves of Aloe excelsa were performed and 1,8-dihydroxy-3-methylanthracenedione (chrysophanol) was isolated and tested for antibacterial activities against four gram negative and five gram positive bacterial strains. The structures of chrysophanol was determined by chemical ...

  2. Antibacterial activity of chrysophanol isolated from Aloe excelsa ...

    African Journals Online (AJOL)

    AJB SERVER

    identification of Aloin A and Aloe emodium has already been achieved in A. excelsa (Coopoosamy and Magwa,. 2006) Chrysophanol is known to occur in both commercial viable species of aloes (Aloe vera and A. ferox), but has not previously been isolated from A. excelsa. MATERIALS AND METHODS. Measurements.

  3. Antimicrobial activity of plant phenols from Chlorophora excelsa and ...

    African Journals Online (AJOL)

    chlorophorin) and 3',4, 5' - trihydroxy - 4' - geranylstilbene (Iroko) from the tree Chlorophora excelsa and (6aR,11aR)-3-hydroxy-8,9-methylenedioxypterocarpan (Maackiain) and 7-hydroxy-4'-methoxyisoflavone (formononetin) from Virgilia oroboides ...

  4. Chemical constituents of the stems of Spathelia excelsa (rutaceae) and activity against Aedes aegypti; Constituintes quimicos do caule de Spathelia excelsa (rutaceae) e atividade contra Aedes aegypti

    Energy Technology Data Exchange (ETDEWEB)

    Freitas, Aline Carvalho de; Lima, Maria da Paz [Instituto Nacional de Pesquisas da Amazonia (INPA), Manaus, AM (Brazil). Coordenacao de Pesquisas em Produtos Naturais], e-mail: mdapaz@inpa.gov.br; Ferreira, Antonio Gilberto [Universidade Federal de Sao Carlos (UFSCAR), SP (Brazil). Dept. de Quimica; Tadei, Wanderli Pedro; Pinto, Ana Cristina da Silva [Instituto Nacional de Pesquisas da Amazonia (INPA), Manaus, AM (Brazil). Lab. de Vetores de Malaria e Dengue

    2009-07-01

    Phytochemical investigation from the stems of Spathelia excelsa (Rutaceae) collected in Amazonas yielded deacetylspathelin (1), 7,8-dimethoxyflindersine (2), new glabretal-type triterpenoid 3{beta}-angeloyl-21,24-epoxy-7{alpha}, 21{alpha}, 23{alpha}, 25-tetrahydroxy-4{alpha}, 4{beta}, 8{beta}, 10{beta}-tetramethyl-25-dimethyl-14,18-cyclo-5{alpha}, 13{alpha}, 14{alpha}, 17{alpha}-cholestane (3), in addition to the known steroids s-sitosterol and stigmasterol. Their structures were established on the basis of spectral data. The compounds 1 and 3 were assayed on Aedes aegypti (larvicidal and adulticidal activities and compound 3 exhibited larvicidal properties with LC{sub 50} of 4,8 {mu}g/mL. (author)

  5. Chemical constituents from the roots of Spathelia excelsa and their antiprotozoal activity

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, Wagner A. dos Santos; Lima, Maria da Paz [Instituto Nacional de Pesquisas da Amazonia (IMPA), Manaus, AM (Brazil). Coordenacao de Pesquisas em Produtos Naturais], e-mail: mdapaz@inpa.gov.br; Ferreira, Antonio Gilberto [Universidade Federal de Sao Carlos (UFSCar), SP (Brazil). Dept. de Quimica; Ferreira, Izabel C. Piloto; Nakamura, Celso V. [Universidade Estadual de Maringa (UEM), PR (Brazil). Dept. de Analises Clinicas

    2009-07-01

    Phytochemical investigation from roots of Spathelia excelsa yielded the chromones 10(2,3-epoxy-3-methylbutanyl) spatheliachromen and 10(2,3-dihydroxy-3-methylbutanyl) methoxyspatheliacromen (5-methoxyspatheliabischromen); limonoid deacetylspathelin and protolimonoid C-21-epimers 3{beta}-angeloyloxy-7a,24,25-trihydroxy-21,23-oxide-14,18-cycloapotirucall -21-hemiacetal; the alkaloids 7,8-dimethoxyflindersin, casimiroin and N-methyl-4,7,8-trimethoxyquinolin-2(1H)-one, besides a mixture of {beta}-sitosterol and stigmasterol. Assays on promastigote forms of Leishmania braziliensis, deacetylspathelin showed moderate activity; and on epimastigote forms of Trypanossoma cruzi, 10(2,3-epoxy-3-methylbutanyl)spatheliachromen exhibited strong activity (IC50 = 11 {mu}g mL-1). (author)

  6. Characterization of Catalase from Psychrotolerant Psychrobacter piscatorii T-3 Exhibiting High Catalase Activity

    OpenAIRE

    Hidetoshi Matsuyma; Isao Yumoto; Hideyuki Kimoto; Kazuaki Yoshimune

    2012-01-01

    A psychrotolerant bacterium, strain T-3 (identified as Psychrobacter piscatorii), that exhibited an extraordinarily high catalase activity was isolated from the drain pool of a plant that uses H2O2 as a bleaching agent. Its cell extract exhibited a catalase activity (19,700 U·mg protein−1) that was higher than that of Micrococcus luteus used for industrial catalase production. Catalase was approximately 10% of the total proteins in the cell extract of the strain. The catalase (PktA) was purif...

  7. The three catalases in Deinococcus radiodurans: Only two show catalase activity.

    Science.gov (United States)

    Jeong, Sun-Wook; Jung, Jong-Hyun; Kim, Min-Kyu; Seo, Ho Seong; Lim, Heon-Man; Lim, Sangyong

    2016-01-15

    Deinococcus radiodurans, which is extremely resistant to ionizing radiation and oxidative stress, is known to have three catalases (DR1998, DRA0146, and DRA0259). In this study, to investigate the role of each catalase, we constructed catalase mutants (Δdr1998, ΔdrA0146, and ΔdrA0259) of D. radiodurans. Of the three mutants, Δdr1998 exhibited the greatest decrease in hydrogen peroxide (H2O2) resistance and the highest increase in intracellular reactive oxygen species (ROS) levels following H2O2 treatments, whereas ΔdrA0146 showed no change in its H2O2 resistance or ROS level. Catalase activity was not attenuated in ΔdrA0146, and none of the three bands detected in an in-gel catalase activity assay disappeared in ΔdrA0146. The purified His-tagged recombinant DRA0146 did not show catalase activity. In addition, the phylogenetic analysis of the deinococcal catalases revealed that the DR1998-type catalase is common in the genus Deinococcus, but the DRA0146-type catalase was found in only 4 of 23 Deinococcus species. Taken together, these results indicate that DR1998 plays a critical role in the anti-oxidative system of D. radiodurans by detoxifying H2O2, but DRA0146 does not have catalase activity and is not involved in the resistance to H2O2 stress. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Characterization of Catalase from Psychrotolerant Psychrobacter piscatorii T-3 Exhibiting High Catalase Activity

    Science.gov (United States)

    Kimoto, Hideyuki; Yoshimune, Kazuaki; Matsuyma, Hidetoshi; Yumoto, Isao

    2012-01-01

    A psychrotolerant bacterium, strain T-3 (identified as Psychrobacter piscatorii), that exhibited an extraordinarily high catalase activity was isolated from the drain pool of a plant that uses H2O2 as a bleaching agent. Its cell extract exhibited a catalase activity (19,700 U·mg protein−1) that was higher than that of Micrococcus luteus used for industrial catalase production. Catalase was approximately 10% of the total proteins in the cell extract of the strain. The catalase (PktA) was purified homogeneously by only two purification steps, anion exchange and hydrophobic chromatographies. The purified catalase exhibited higher catalytic efficiency and higher sensitivity of activity at high temperatures than M. luteus catalase. The deduced amino acid sequence showed the highest homology with catalase of Psycrobacter cryohalolentis, a psychrotolelant bacterium obtained from Siberian permafrost. These findings suggest that the characteristics of the PktA molecule reflected the taxonomic relationship of the isolate as well as the environmental conditions (low temperatures and high concentrations of H2O2) under which the bacterium survives. Strain T-3 efficiently produces a catalase (PktA) at a higher rate than Exiguobacterium oxidotolerans, which produces a very strong activity of catalase (EktA) at a moderate rate, in order to adapt to high concentration of H2O2. PMID:22408420

  9. Characterization of Catalase from Psychrotolerant Psychrobacter piscatorii T-3 Exhibiting High Catalase Activity

    Directory of Open Access Journals (Sweden)

    Hidetoshi Matsuyma

    2012-02-01

    Full Text Available A psychrotolerant bacterium, strain T-3 (identified as Psychrobacter piscatorii, that exhibited an extraordinarily high catalase activity was isolated from the drain pool of a plant that uses H2O2 as a bleaching agent. Its cell extract exhibited a catalase activity (19,700 U·mg protein−1 that was higher than that of Micrococcus luteus used for industrial catalase production. Catalase was approximately 10% of the total proteins in the cell extract of the strain. The catalase (PktA was purified homogeneously by only two purification steps, anion exchange and hydrophobic chromatographies. The purified catalase exhibited higher catalytic efficiency and higher sensitivity of activity at high temperatures than M. luteus catalase. The deduced amino acid sequence showed the highest homology with catalase of Psycrobacter cryohalolentis, a psychrotolelant bacterium obtained from Siberian permafrost. These findings suggest that the characteristics of the PktA molecule reflected the taxonomic relationship of the isolate as well as the environmental conditions (low temperatures and high concentrations of H2O2 under which the bacterium survives. Strain T-3 efficiently produces a catalase (PktA at a higher rate than Exiguobacterium oxidotolerans, which produces a very strong activity of catalase (EktA at a moderate rate, in order to adapt to high concentration of H2O2.

  10. Catalase and NO CATALASE ACTIVITY1 promote autophagy-dependent cell death in Arabidopsis

    DEFF Research Database (Denmark)

    Hackenberg, Thomas; Juul, Trine; Auzina, Aija

    2013-01-01

    Programmed cell death often depends on generation of reactive oxygen species, which can be detoxified by antioxidative enzymes, including catalases. We previously isolated catalase-deficient mutants (cat2) in a screen for resistance to hydroxyurea-induced cell death. Here, we identify...... an Arabidopsis thaliana hydroxyurea-resistant autophagy mutant, atg2, which also shows reduced sensitivity to cell death triggered by the bacterial effector avrRpm1. To test if catalase deficiency likewise affected both hydroxyurea and avrRpm1 sensitivity, we selected mutants with extremely low catalase...... activities and showed that they carried mutations in a gene that we named NO CATALASE ACTIVITY1 (NCA1). nca1 mutants showed severely reduced activities of all three catalase isoforms in Arabidopsis, and loss of NCA1 function led to strong suppression of RPM1-triggered cell death. Basal and starvation...

  11. Antioxidant activity and chemical composition of Juniperus excelsa ssp. polycarpos wood extracts.

    Science.gov (United States)

    Hosseinihashemi, S K; Dadpour, A; Lashgari, A

    2017-03-01

    Extracts from the wood of Juniperus excelsa ssp. polycarpos were analysed for their antioxidant activity using the DPPH method and compared with ascorbic acid and butylated hydroxytoluene. The most active extracts were analysed for their chemical composition using gas chromatography-mass spectrometry. Acetone extract was found to be moderately active as an antioxidant agent at 58.38%, which was lower than the value of vitamin C (98.56%) at the concentration of 14.20 mg/mL. The major components identified in the acetone extract as trimethylsilyl (TMS) derivatives were pimaric acid TMS (24.56%), followed by α-d-glucopyranoside,1,3,4,6-tetrakis-O-(TMS)-β-d-fructofuranosyl 2,3,4,6-tetrakis-O-(TMS) (21.39%), triflouromethyl-bis-(TMS)methyl ketone (9.32%), and cedrol (0.72%). The dissolved water:methanol (1:1 v/v) partitioned from acetone extract afforded 12 fractions; among them, the F9 fraction was found to have good antioxidant activity (88.49%) at the concentration of 14.20 mg/mL. The major compounds identified in F9 fraction were α-d-glucopyranoside, 1,3,4,6-tetrakis-O-(TMS) (20.22%) and trifluoromethyl-bis-(TMS)methyl ketone (5.10%).

  12. The three catalases in Deinococcus radiodurans: Only two show catalase activity

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Sun-Wook [Research Division for Biotechnology, Korea Atomic Energy Research Institute, Jeongeup, 580-185 (Korea, Republic of); Department of Biological Sciences, College of Biological Sciences and Biotechnology, Chungnam National University, Daejeon, 305-764 (Korea, Republic of); Jung, Jong-Hyun; Kim, Min-Kyu; Seo, Ho Seong [Research Division for Biotechnology, Korea Atomic Energy Research Institute, Jeongeup, 580-185 (Korea, Republic of); Lim, Heon-Man [Department of Biological Sciences, College of Biological Sciences and Biotechnology, Chungnam National University, Daejeon, 305-764 (Korea, Republic of); Lim, Sangyong, E-mail: saylim@kaeri.re.kr [Research Division for Biotechnology, Korea Atomic Energy Research Institute, Jeongeup, 580-185 (Korea, Republic of)

    2016-01-15

    Deinococcus radiodurans, which is extremely resistant to ionizing radiation and oxidative stress, is known to have three catalases (DR1998, DRA0146, and DRA0259). In this study, to investigate the role of each catalase, we constructed catalase mutants (Δdr1998, ΔdrA0146, and ΔdrA0259) of D. radiodurans. Of the three mutants, Δdr1998 exhibited the greatest decrease in hydrogen peroxide (H{sub 2}O{sub 2}) resistance and the highest increase in intracellular reactive oxygen species (ROS) levels following H{sub 2}O{sub 2} treatments, whereas ΔdrA0146 showed no change in its H{sub 2}O{sub 2} resistance or ROS level. Catalase activity was not attenuated in ΔdrA0146, and none of the three bands detected in an in-gel catalase activity assay disappeared in ΔdrA0146. The purified His-tagged recombinant DRA0146 did not show catalase activity. In addition, the phylogenetic analysis of the deinococcal catalases revealed that the DR1998-type catalase is common in the genus Deinococcus, but the DRA0146-type catalase was found in only 4 of 23 Deinococcus species. Taken together, these results indicate that DR1998 plays a critical role in the anti-oxidative system of D. radiodurans by detoxifying H{sub 2}O{sub 2}, but DRA0146 does not have catalase activity and is not involved in the resistance to H{sub 2}O{sub 2} stress. - Highlights: • The dr1998 mutant strain lost 90% of its total catalase activity. • Increased ROS levels and decreased H{sub 2}O{sub 2} resistance were observed in dr1998 mutants. • Lack of drA0146 did not affect any oxidative stress-related phenotypes. • The purified DRA0146 did not show catalase activity.

  13. Growth of catalase A and catalase T deficient mutant strains of Saccharomyces cerevisiae on ethanol and oleic acid : Growth profiles and catalase activities in relation to microbody proliferation

    NARCIS (Netherlands)

    Klei, Ida J. van der; Rytka, Joanna; Kunau, Wolf H.; Veenhuis, Marten

    The parental strain (A+T+) of Saccharomyces cerevisiae and mutants, deficient in catalase T (A+T-), catalase A (A-T+) or both catalases (A-T-), grew on ethanol and oleic acid with comparable doubling times. Specific activities of catalase were low in glucose- and ethanol-grown cells. In the two

  14. Blood superoxiddismutase and catalase: enzymes activity under oxidative stress conditions

    Directory of Open Access Journals (Sweden)

    Каріна Леонідівна Шамелашвілі

    2015-05-01

    Full Text Available The activity of catalase and superoxide dismutase depends not only on the used compounds of rhenium, and also on their dimensional structure and form of applying. It is established that the cis- and trans-isomers of complex compounds of rhenium did countervailing effect on superoxide dismutase and catalase activities. Cis-isomers of Rhenium dycarboxylats agreed increased activity of superoxide dismutase and catalase. While under the action of trans-isomers, where increased activity of superoxide dismutase, catalase activity decreased

  15. Photocatalytic degradation of synthetic food dye, sunset yellow FCF (FD&C yellow no. 6) by Ailanthus excelsa Roxb. possessing antioxidant and cytotoxic activity.

    Science.gov (United States)

    Deepika, Subramanyam; Harishkumar, Rajendran; Dinesh, Murugesan; Abarna, Rajadurai; Anbalagan, Moorthy; Roopan, Selvaraj Mohana; Selvaraj, Chinnadurai Immanuel

    2017-12-01

    The purpose of our work is to identify the bioactive compounds of bark and leaves extract from Ailanthus excelsa Roxb. and to explore its effectiveness against synthetic food dye. The presence of primary and secondary metabolites was confirmed by carrying out phytochemicals analysis. With the prior knowledge accessible on the indispensable secondary metabolites holding antioxidant and cytotoxicity activity, the quantitative screening of total phenolic and flavonoid content in methanolic and aqueous extract of bark and leaves from Ailanthus excelsa were done. Comparatively, a higher value of flavonoid (161±0.3μg/mg) and phenolic acid content (152.4±0.14μg/mg) was found in bark extract. By FTIR analysis, the characteristic peak was obtained at 1581.63 and 1598.99cm-1 confirmed the presence of functional groups associated to flavonoids and other phenolic groups respectively. In bark extract, 81% of DPPH inhibition was observed when compared to ascorbic acid (standard) 92% of free radical scavenging activity. Bark extract from Ailanthus excelsa exhibited 71% cytotoxicity against HeLa cell line (cervical cancer). In examining the toxicity level of crude extracts with red blood cells (RBC), the bark extract was showed a very less (2.8%) haemolytic activity. They also showed maximum zone of inhibition in antibacterial activity i.e. 13±0.5mm against Escherichia coli culture. At a concentration of 10mg/mL of crude extract from A. excelsa, 55% degradation of sunset yellow dye was observed. It concludes that, the compounds present in the A. excelsa, especially the bark extract showed better photocatalytic, haemolytic, antioxidant, cytotoxicity and antibacterial activity when compared to leaves extract. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Chemical composition and antimicrobial activity of essential oils of Juniperus excelsa Bieb. (Cupressaceae) grown in R. Macedonia.

    Science.gov (United States)

    Sela, Floresha; Karapandzova, Marija; Stefkov, Gjose; Cvetkovikj, Ivana; Kulevanova, Svetlana

    2015-01-01

    There are no information of the yield, chemical composition and antimicrobial activity of essential oils of berries (EOB) or leaves (EOL) of Juniperus excelsa Bieb. (Cupressaceae) growing wild in R. Macedonia. Plant material was collected from two localities during two seasons. Essential oil composition was analyzed by gas chromatography/flame ionization detector/mass spectrometry (GC/FID/MS) and antimicrobial screening was made by disc diffusion and broth dilution method. EOB yield ranged from 1.6-9.4 ml/kg and from 8.9-13.9 ml/kg for EOL. Two chemotypes of essential oil were differentiated, α-pinene-type (with 70.81% α-pinene in EOB and 33.83% in EOL), also containing limonene, β-pinene and β-myrcene while the sabinene-type (with 58.85-62.58% sabinene in EOB and 28.52-29.49% in EOL), was rich in α-pinene, β-myrcene, limonene, cis-thujone, terpinolene and α-thujene. The most sensitive bacteria to the antimicrobial activity of EOB was Haemophilus influenzae (MIC = 31 μl/ml). EOL have showed high activity towards: Staphylococcus aureus, Streptococcus pyogenes and Haemophilus influenzae (MIC = 125 μl/ml). The pinene-type of essential oil showed moderate activity against Streptococcus pneumoniae, Staphylococcus aureus, Streptococcus agalactiae, Streptococcus pyogenes, Corynebacterium spp. and Campylobacter jejuni (MIC >50%). The sabinene-type of the oil showed moderate activity to Streptococcus pyogenes, Haemopilus influenzae, Campylobacter jejuni and Escherichia coli (MIC >50%). No activity was observed toward Candida albicans. The analysis of EOB and EOL revealed two chemotypes (α-pinene and sabinene type) clearly depended on the geographical origin of the Macedonian Juniperus excelsa which also affected the antimicrobial activity of these oils.

  17. Development of method for the mineral water catalase activity determination

    Directory of Open Access Journals (Sweden)

    Olena М. Nikipelova

    2015-03-01

    Full Text Available Biological effects of mineral water depend not only on the chemical composition but also on the metabolic products of microbial cenosis. Among numerous microorganisms constituting the autochthonous microflora of mineral waters, we do evolve the saprophytic organisms producing the catalase, the saprophytes’ physiological and biological role being proven a long ago. The research aim was to develop a method for determination of mineral water catalase activity. Analyzed are various methods to determine the catalase activity in biological objects. Developed is a spectrophotometric method for determination of mineral water catalase activity. The method is efficiently tested with series of Ukrainian mineral waters. Calculated are the relative standard deviations which are significantly below normal errors, admitted at spectroscopic analysis and at the optic density range. The given method provides sufficient accuracy and convergence when estimating the mineral waters catalase activity, allowing to introduce a new index to assess the quality and biological value.

  18. Catalase activity of cassava ( Manihot esculenta ) plant under ...

    African Journals Online (AJOL)

    Cassava leaf extract infected with the African cassava mosaic virus and uninfected were prepared and used as crude catalase extract. The total protein was determined by Biuret method and activity of the crude catalase was compared using hydrogen peroxide as substrate. Infected leaf extract had 141.02 ± 3.536 mg/mL ...

  19. Catalase activity of cassava (Manihot esculenta) plant under African ...

    African Journals Online (AJOL)

    aghomotsegin

    The H2O2 produced is then scavenged by catalase and several classes of peroxidases. Peroxi- dases decompose H2O2 by the oxidation of phenolic compounds. The catalase is a tetrameric heme protein, found in peroxisomes, cytosol and mitochondria (Krych et al., 2014). This enzyme has hyperoxidase activity which.

  20. The catalase activity of diiron adenine deaminase

    Energy Technology Data Exchange (ETDEWEB)

    Kamat S. S.; Swaminathan S.; Holmes-Hampton, G. P.; Bagaria, A.; Kumaran, D.; Tichy, S. E.; Gheyi, T.; Zheng, X.; Bain, K.; Groshong, C.; Emtage, S.; Sauder, J. M.; Burley, S. K.; Lindahl, P. A.; Raushel, F. M.

    2011-12-01

    Adenine deaminase (ADE) from the amidohydrolase superfamily (AHS) of enzymes catalyzes the conversion of adenine to hypoxanthine and ammonia. Enzyme isolated from Escherichia coli was largely inactive toward the deamination of adenine. Molecular weight determinations by mass spectrometry provided evidence that multiple histidine and methionine residues were oxygenated. When iron was sequestered with a metal chelator and the growth medium supplemented with Mn{sup 2+} before induction, the post-translational modifications disappeared. Enzyme expressed and purified under these conditions was substantially more active for adenine deamination. Apo-enzyme was prepared and reconstituted with two equivalents of FeSO{sub 4}. Inductively coupled plasma mass spectrometry and Moessbauer spectroscopy demonstrated that this protein contained two high-spin ferrous ions per monomer of ADE. In addition to the adenine deaminase activity, [Fe{sup II}/Fe{sup II}]-ADE catalyzed the conversion of H{sub 2}O{sub 2} to O{sub 2} and H{sub 2}O. The values of k{sub cat} and k{sub cat}/K{sub m} for the catalase activity are 200 s{sup -1} and 2.4 x 10{sup 4} M{sup -1} s{sup -1}, respectively. [Fe{sup II}/Fe{sup II}]-ADE underwent more than 100 turnovers with H{sub 2}O{sub 2} before the enzyme was inactivated due to oxygenation of histidine residues critical for metal binding. The iron in the inactive enzyme was high-spin ferric with g{sub ave} = 4.3 EPR signal and no evidence of anti-ferromagnetic spin-coupling. A model is proposed for the disproportionation of H{sub 2}O{sub 2} by [Fe{sup II}/Fe{sup II}]-ADE that involves the cycling of the binuclear metal center between the di-ferric and di-ferrous oxidation states. Oxygenation of active site residues occurs via release of hydroxyl radicals. These findings represent the first report of redox reaction catalysis by any member of the AHS.

  1. Growth-Dependent Catalase Localization in Exiguobacterium oxidotolerans T-2-2T Reflected by Catalase Activity of Cells

    Science.gov (United States)

    Hanaoka, Yoshiko; Takebe, Fumihiko; Nodasaka, Yoshinobu; Hara, Isao; Matsuyama, Hidetoshi; Yumoto, Isao

    2013-01-01

    A psychrotolerant and H2O2-resistant bacterium, Exiguobacterium oxidotolerans T-2-2T, exhibits extraordinary H2O2 resistance and produces catalase not only intracellularly but also extracellularly. The intracellular and extracellular catalases exhibited the same enzymatic characteristics, that is, they exhibited the temperature-dependent activity characteristic of a cold-adapted enzyme, their heat stabilities were similar to those of mesophilic enzymes and very high catalytic intensity. In addition, catalase gene analysis indicated that the bacterium possessed the sole clade 1 catalase gene corresponding to intracellular catalase. Hence, intracellular catalase is secreted into the extracellular space. In addition to intracellular and extracellular catalases, the inner circumference of the cells showed the localization of catalase in the mid-stationary growth phase, which was observed by immunoelectron microscopy using an antibody against the intracellular catalase of the strain. The cells demonstrated higher catalase activity in the mid-stationary growth phase than in the exponential growth phase. The catalase localized in the inner circumference can be dissociated by treatment with Tween 60. Thus, the localized catalase is not tightly bound to the inner circumference of the cells and may play a role in the oxidative defense of the cells under low metabolic state. PMID:24204687

  2. Polypeptides having catalase activity and polynucleotides encoding same

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Ye; Duan, Junxin; Zhang, Yu; Tang, Lan

    2017-05-02

    Provided are isolated polypeptides having catalase activity and polynucleotides encoding the polypeptides. Also provided are nucleic acid constructs, vectors and host cells comprising the polynucleotides as well as methods of producing and using the polypeptides.

  3. Development of method for the mineral water catalase activity determination

    OpenAIRE

    Olena М. Nikipelova; Аlena Yu. Kisilevskaya; Lyudmyla B. Solodova

    2015-01-01

    Biological effects of mineral water depend not only on the chemical composition but also on the metabolic products of microbial cenosis. Among numerous microorganisms constituting the autochthonous microflora of mineral waters, we do evolve the saprophytic organisms producing the catalase, the saprophytes’ physiological and biological role being proven a long ago. The research aim was to develop a method for determination of mineral water catalase activity. Analyzed are various methods to det...

  4. Catalase and NO CATALASE ACTIVITY1 Promote Autophagy-Dependent Cell Death in Arabidopsis[C][W][OPEN

    Science.gov (United States)

    Hackenberg, Thomas; Juul, Trine; Auzina, Aija; Gwiżdż, Sonia; Małolepszy, Anna; Van Der Kelen, Katrien; Dam, Svend; Bressendorff, Simon; Lorentzen, Andrea; Roepstorff, Peter; Lehmann Nielsen, Kåre; Jørgensen, Jan-Elo; Hofius, Daniel; Breusegem, Frank Van; Petersen, Morten; Andersen, Stig Uggerhøj

    2013-01-01

    Programmed cell death often depends on generation of reactive oxygen species, which can be detoxified by antioxidative enzymes, including catalases. We previously isolated catalase-deficient mutants (cat2) in a screen for resistance to hydroxyurea-induced cell death. Here, we identify an Arabidopsis thaliana hydroxyurea-resistant autophagy mutant, atg2, which also shows reduced sensitivity to cell death triggered by the bacterial effector avrRpm1. To test if catalase deficiency likewise affected both hydroxyurea and avrRpm1 sensitivity, we selected mutants with extremely low catalase activities and showed that they carried mutations in a gene that we named NO CATALASE ACTIVITY1 (NCA1). nca1 mutants showed severely reduced activities of all three catalase isoforms in Arabidopsis, and loss of NCA1 function led to strong suppression of RPM1-triggered cell death. Basal and starvation-induced autophagy appeared normal in the nca1 and cat2 mutants. By contrast, autophagic degradation induced by avrRpm1 challenge was compromised, indicating that catalase acted upstream of immunity-triggered autophagy. The direct interaction of catalase with reactive oxygen species could allow catalase to act as a molecular link between reactive oxygen species and the promotion of autophagy-dependent cell death. PMID:24285797

  5. A Simple Assay for Measuring Catalase Activity: A Visual Approach

    Science.gov (United States)

    Iwase, Tadayuki; Tajima, Akiko; Sugimoto, Shinya; Okuda, Ken-ichi; Hironaka, Ippei; Kamata, Yuko; Takada, Koji; Mizunoe, Yoshimitsu

    2013-01-01

    In this study, an assay that combines the ease and simplicity of the qualitative approach for measuring catalase activity was developed. The assay reagents comprised only hydrogen peroxide and Triton X-100. The enzyme-generated oxygen bubbles trapped by Triton X-100 were visualized as foam, whose height was estimated. A calibration plot using the defined unit of catalase activity yielded the best linear fit over a range of 20–300 units (U) (y = 0.3794x − 2.0909, r2 = 0.993). The assay precision and reproducibility at 100 U were 4.6% and 4.8%, respectively. The applicability of the assay for measuring the catalase activity of various samples was assessed using laboratory strains of Escherichia coli, catalase-deficient isogenic mutants, clinically isolated Shiga toxin-producing E. coli, and human cells. The assay generated reproducible results. In conclusion, this new assay can be used to measure the catalase activity of bacterial isolates and human cells. PMID:24170119

  6. Catalase activity in healthy and inflamed pulp tissues of permanent ...

    African Journals Online (AJOL)

    Aim: To evaluate catalase (CAT, EC 1.11.1.6) activity in healthy and inflamed dental pulp of young patient's teeth and to investigate if an active defense system oxidizing agents is present as a response to bacterial invasion. Materials and Methods: Twenty young patients between 15 and 25 ages, who were diagnosed to be ...

  7. Catalase activity in healthy and inflamed pulp tissues of permanent ...

    African Journals Online (AJOL)

    2015-11-02

    Nov 2, 2015 ... The specimens were collected during endodontic treatment or by longitudinally grooving and splitting the teeth (if extracted). Catalase activity was determined through spectrophotometric methods and an independent sample t‑test assessed the significance of differences between the groups. Results: There ...

  8. Evaluation of salivary catalase activity in blighted ovum gestation

    Directory of Open Access Journals (Sweden)

    Maryam Ahmadizadeh

    2016-05-01

    Full Text Available Background: Anembryonic gestation (blighted ovum is the most common identifiable pathology in the first trimester of pregnancy, always leads to miscarriage. Early pregnancy failures from blighted ovum are often due to chromosomal abnormalities and a poor quality of sperm or egg. Oxidative stresses as a factor of disturbance balance between the production of free radicals and antioxidant defenses is involved in the pathogenesis of many diseases, including mouth and throat cancer and cardiovascular disease. Catalase is one of the defensive systems against damages caused by oxidative stress in human. The aim of this study was to compare the activity of salivary catalase in women with blighted ovum and women with history of normal pregnancy. Methods: This case-control study was performed on 34 patient women with blighted ovum and 34 healthy women as a control group. The study was performed in biochemistry laboratory at the University of Guilan from October 2015 to July 2015. The age range was 20-44 years and 18-45 years in patient and control groups, respectively. Unstimulated saliva samples were collected using spitting method. Catalase activity was measured by evaluating the constant rate of hydrogen peroxide decomposition in patient and control groups. Results: The patient group matched with healthy subjects in average age and having no other diseases history. The biochemical enzymatic assays indicate that the average catalase activities of saliva in patient and control groups were 14.47±3.8 and 16.42±3.48, respectively. Therefore, the catalase activity was significantly reduced in patient group as compared to the control group (P=0.03. Conclusion: The obtained results suggested that oxidative stress plays an important role in the pathogenesis of blighted ovum. Therefore, determination the activity of other antioxidant enzymes, in addition to catalse, may be used as a marker for diagnosis of blighted ovum. More studies with larger studied

  9. Chemical characterization and radical scavenging activity of leaves of Juniperus foetidisima, J. excelsa and J. communis from Macedonian flora

    Directory of Open Access Journals (Sweden)

    Marija Karapandzova

    2014-12-01

    Full Text Available Chemical characterization of three Juniperus species: J. foetidisima (JF, J. excelsa (JE and J. communis (JC from Macedonian flora enclosed determination of yield and essential oil composition of the oils obtained by hydro-distillation of dried leaves and determination of the content of total phenols and total flavonoids in dried plant material. GC/FID/MS analysis showed mainly monoterpene profile of the JC oil and combined monoterpene/sesquiterpene profile of JF and JE oils. Sesquiterpene cedrol was found as an important constituent of the JF and JE, thus the JF oil was characterized by three main components (a-pinene, limonene and cedrol, in amount up to 67.63%, 27.11% and 33.91%, respectively and JE oil by four components (a-pinene, sabinene, cis-thujone and cedrol, in amount up to 33.83%, 29.49%, 26.20% and 24.44%, respectively. The JC oil was free of cedrol, but contained relatively large sesquiterpene fraction (sesquiterpene hydrocarbons and oxygen containing sesquiterpenes in amounts up to 28.64% and 13.57%, respectively. The JC oil was characterized by three monoterpene components (a-pinene, sabinene and terpinen-4-ol, presented up to 28.68%, 16.27% and 12.16%, respectively. The content of total phenols determined by Folin-Ciocalteu method ranged from 96.18-122.91 mg GAE/g dw (water extraction while the content of total flavonoids ranged from 2.05-11.91 mg CE/g dw (ethanol extraction. Both water and ethanol extracts possessed radical scavenging activity against DPPH radical. Water extracts were more powerful with % of inhibition of DPPH ranging up to 64.52%, 67.40% and 78.23% for water extract (10 mg/ml of JF, JE and JC, respectively. Obtained results showed correlation with the content of total phenols.

  10. The Catalase Activity of Catalase-Peroxidases Is Modulated by Changes in the pKa of the Distal Histidine.

    Science.gov (United States)

    Machuqueiro, Miguel; Victor, Bruno; Switala, Jacek; Villanueva, Jacylyn; Rovira, Carme; Fita, Ignacio; Loewen, Peter C

    2017-05-02

    The unusual Met-Tyr-Trp adduct composed of cross-linked side chains along with an associated mobile Arg is essential for catalase activity in catalase-peroxidases. In addition, acidic residues in the entrance channel, in particular an Asp and a Glu ∼7 and ∼15 Å, respectively, from the heme, significantly enhance catalase activity. The mechanism by which these channel carboxylates influence catalase activity is the focus of this work. Seventeen new variants with fewer and additional acidic residues have been constructed and characterized structurally and for enzymatic activity, revealing that their effect on activity is roughly inversely proportional to their distance from the heme and adduct, suggesting that the electrostatic potential of the heme cavity may be affected. A discrete group of protonable residues are contained within a 15 Å sphere surrounding the heme iron, and a computational analysis reveals that the pKa of the distal His112, alone, is modulated within the pH range of catalase activity by the remote acidic residues in a pattern consistent with its protonated form having a key role in the catalase reaction cycle. The electrostatic potential also impacts the catalatic reaction through its influence on the charged status of the Met-Tyr-Trp adduct.

  11. Catalase-peroxidases (KatG) exhibit NADH oxidase activity.

    Science.gov (United States)

    Singh, Rahul; Wiseman, Ben; Deemagarn, Taweewat; Donald, Lynda J; Duckworth, Harry W; Carpena, Xavi; Fita, Ignacio; Loewen, Peter C

    2004-10-08

    Catalase-peroxidases (KatG) produced by Burkholderia pseudomallei, Escherichia coli, and Mycobacterium tuberculosis catalyze the oxidation of NADH to form NAD+ and either H2O2 or superoxide radical depending on pH. The NADH oxidase reaction requires molecular oxygen, does not require hydrogen peroxide, is not inhibited by superoxide dismutase or catalase, and has a pH optimum of 8.75, clearly differentiating it from the peroxidase and catalase reactions with pH optima of 5.5 and 6.5, respectively, and from the NADH peroxidase-oxidase reaction of horseradish peroxidase. B. pseudomallei KatG has a relatively high affinity for NADH (Km=12 microm), but the oxidase reaction is slow (kcat=0.54 min(-1)) compared with the peroxidase and catalase reactions. The catalase-peroxidases also catalyze the hydrazinolysis of isonicotinic acid hydrazide (INH) in an oxygen- and H2O2-independent reaction, and KatG-dependent radical generation from a mixture of NADH and INH is two to three times faster than the combined rates of separate reactions with NADH and INH alone. The major products from the coupled reaction, identified by high pressure liquid chromatography fractionation and mass spectrometry, are NAD+ and isonicotinoyl-NAD, the activated form of isoniazid that inhibits mycolic acid synthesis in M. tuberculosis. Isonicotinoyl-NAD synthesis from a mixture of NAD+ and INH is KatG-dependent and is activated by manganese ion. M. tuberculosis KatG catalyzes isonicotinoyl-NAD formation from NAD+ and INH more efficiently than B. pseudomallei KatG.

  12. Growth-Dependent Catalase Localization in Exiguobacterium oxidotolerans T-2-2T Reflected by Catalase Activity of Cells

    OpenAIRE

    Yoshiko Hanaoka; Fumihiko Takebe; Yoshinobu Nodasaka; Isao Hara; Hidetoshi Matsuyama; Isao Yumoto

    2013-01-01

    A psychrotolerant and H2O2-resistant bacterium, Exiguobacterium oxidotolerans T-2-2(T), exhibits extraordinary H2O2 resistance and produces catalase not only intracellularly but also extracellularly. The intracellular and extracellular catalases exhibited the same enzymatic characteristics, that is, they exhibited the temperature-dependent activity characteristic of a cold-adapted enzyme, their heat stabilities were similar to those of mesophilic enzymes and very high catalytic intensity. In ...

  13. Antioxidant Activity of SOD and Catalase Conjugated with Nanocrystalline Ceria

    Directory of Open Access Journals (Sweden)

    Dmitry Gil

    2017-02-01

    Full Text Available Interactions of nanoparticles with biological matter—both somatically and in nature—draw scientists’ attention. Nanoparticulate systems are believed to be our saviors, acting as versatile drug delivery vehicles. However, they can also cause life-threatening bodily damage. One of the most important properties of nanocrystalline cerium dioxide is its antioxidant activity, which decreases the abundance of reactive oxygen species during inflammation. In this paper, we report on synergistic effects of inorganic cerium oxide (IV nanoparticles conjugated with the antioxidative enzymes superoxide dismutase and catalase on scavenging oxygen and nitrogen radicals.

  14. A gasometric method to determine erythrocyte catalase activity

    Directory of Open Access Journals (Sweden)

    A.J.S. Siqueira

    1999-09-01

    Full Text Available We describe a new gasometric method to determine erythrocyte catalase activity by the measurement of the volume of oxygen produced as a result of hydrogen peroxide decomposition in a system where enzyme and substrate are separated in a special reaction test tube connected to a manometer and the reagents are mixed with a motor-driven stirrer. The position of the reagents in the test tube permits the continuous measurement of oxygen evolution from the time of mixing, without the need to stop the reaction by the addition of acid after each incubation time. The enzyme activity is reported as KHb, i.e., mg hydrogen peroxide decomposed per second per gram of hemoglobin (s-1 g Hb-1. The value obtained for catalase activity in 28 samples of hemolyzed human blood was 94.4 ± 6.17 mg H2O2 s-1 g Hb-1. The results obtained were precise and consistent, indicating that this rapid, simple and inexpensive method could be useful for research and routine work.

  15. Catalase-only nanoparticles prepared by shear alone: Characteristics, activity and stability evaluation.

    Science.gov (United States)

    Huang, Xiao-Nan; Du, Xin-Ying; Xing, Jin-Feng; Ge, Zhi-Qiang

    2016-09-01

    Catalase is a promising therapeutic enzyme; however, it carries risks of inactivation and rapid degradation when it is used in practical bioprocess, such as delivery in vivo. To overcome the issue, we made catalase-only nanoparticles using shear stress alone at a moderate shear rate of 217s(-1) in a coaxial cylinder flow cell. Properties of nanoparticles, including particle size, polydispersity index and zeta potential, were characterized. The conformational changes of pre- and post-sheared catalase were determined using spectroscopy techniques. The results indicated that the conformational changes of catalase and reduction in α-helical content caused by shear alone were less significant than that by desolvation method. Catalase-only nanoparticles prepared by single shear retained over 90% of its initial activity when compared with the native catalase. Catalase nanoparticles lost only 20% of the activity when stored in phosphate buffer solution for 72h at 4°C, whereas native catalase lost 53% under the same condition. Especially, the activity of nanogranulated catalase was decreased only slightly in the simulated intestinal fluid containing α-chymotrypsin during 4h incubation at 37°C, implying that the catalase nanoparticle was more resistant to the degradation of proteases than native catalase molecules. Overall, catalase-only nanoparticles offered a great potential to stabilize enzymes for various pharmaceutical applications. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. The Pseudomonas secretory product pyocyanin inhibits catalase activity in human lung epithelial cells.

    Science.gov (United States)

    O'Malley, Yunxia Q; Reszka, Krzysztof J; Rasmussen, George T; Abdalla, Maher Y; Denning, Gerene M; Britigan, Bradley E

    2003-11-01

    Pyocyanin, produced by Pseudomonas aeruginosa, has many deleterious effects on human cells that relate to its ability to generate reactive oxygen species (ROS), such as superoxide and hydrogen peroxide. Human cells possess several mechanisms to protect themselves from ROS, including manganese superoxide dismutase (MnSOD), copper zinc superoxide dismutase (CuZnSOD), and catalase. Given the link between pyocyanin-mediated epithelial cell injury and oxidative stress, we assessed pyocyanin's effect on MnSOD, CuZnSOD, and catalase levels in the A549 human alveolar epithelial cell line and in normal human bronchial epithelial cells. In both cell types, CuZnSOD and MnSOD were unaltered, but over 24 h pyocyanin significantly decreased cellular catalase activity and protein content. Pyocyanin also decreased catalase mRNA. Overexpression of MnSOD in A549 cells prevented pyocyanin-mediated loss of catalase protein, but catalase activity still declined. Furthermore, pyocyanin decreased catalase activity, but not protein, in A549 cells overexpressing human catalase. These data suggest a direct effect of pyocyanin on catalase activity. Addition of pyocyanin to catalase in a cell-free system also decreased catalase activity. Mammalian catalase binds four NADPH molecules, helping maintain enzyme activity. Spin-trapping data suggest that pyocyanin directly oxidizes this NADPH, producing superoxide. We conclude that pyocyanin may decrease cellular catalase activity via both transcriptional regulation and direct inactivation of the enzyme. Decreased cellular catalase activity and failure to augment MnSOD could contribute to pyocyanin-dependent cytotoxicity.

  17. A Chaperone Function of NO CATALASE ACTIVITY1 Is Required to Maintain Catalase Activity and for Multiple Stress Responses in Arabidopsis

    Science.gov (United States)

    Li, Jing; Liu, Juntao; Wang, Guoqiang; Cha, Joon-Yung; Li, Guannan; Chen, She; Li, Zhen; Guo, Jinghua; Zhang, Caiguo; Yang, Yongqing; Kim, Woe-Yeon; Yun, Dae-Jin; Schumaker, Karen S.; Chen, Zhongzhou; Guo, Yan

    2015-01-01

    Catalases are key regulators of reactive oxygen species homeostasis in plant cells. However, the regulation of catalase activity is not well understood. In this study, we isolated an Arabidopsis thaliana mutant, no catalase activity1-3 (nca1-3) that is hypersensitive to many abiotic stress treatments. The mutated gene was identified by map-based cloning as NCA1, which encodes a protein containing an N-terminal RING-finger domain and a C-terminal tetratricopeptide repeat-like helical domain. NCA1 interacts with and increases catalase activity maximally in a 240-kD complex in planta. In vitro, NCA1 interacts with CATALASE2 (CAT2) in a 1:1 molar ratio, and the NCA1 C terminus is essential for this interaction. CAT2 activity increased 10-fold in the presence of NCA1, and zinc ion binding of the NCA1 N terminus is required for this increase. NCA1 has chaperone protein activity that may maintain the folding of catalase in a functional state. NCA1 is a cytosol-located protein. Expression of NCA1 in the mitochondrion of the nca1-3 mutant does not rescue the abiotic stress phenotypes of the mutant, while expression in the cytosol or peroxisome does. Our results suggest that NCA1 is essential for catalase activity. PMID:25700484

  18. Mechanism of the Increase in Catalase Activity through Microbody Development in Wounded Sweet Potato Root Tissue

    OpenAIRE

    Muneharu, ESAKA; Masayoshi, MAESHIMA; Tadashi, Asahi; Laboratory of Biochemistry, Faculty of Agriculture, Nagoya University

    1983-01-01

    An increase in catalase activity accompanied by microbody development in wounded sweet potato root tissue was investigated with a specific antibody against sweet potato catalase. The increase was completely inhibited by cycloheximide. Analysis with single radial immunodiffusion method showed that protein immunoprecipitated by the antibody increased in wounded tissue, indicating the involvement of de novo synthesis of catalase protein in the activity-increase. The activity-increase was, howeve...

  19. Endothelin-1 stimulates catalase activity through the PKCδ mediated phosphorylation of Serine 167

    Science.gov (United States)

    Rafikov, Ruslan; Kumar, Sanjiv; Aggarwal, Saurabh; Hou, Yali; Kangath, Archana; Pardo, Daniel; Fineman, Jeffrey R.; Black, Stephen M.

    2013-01-01

    Our previous studies have shown that endothelin-1 (ET-1) stimulates catalase activity in endothelial cells and lambs with acute increases in pulmonary blood flow (PBF), without altering gene expression. The purpose of this study was to investigate the molecular mechanism by which this occurs. Exposing pulmonary arterial endothelial cells (PAEC) to ET-1 increased catalase activity and decreased cellular hydrogen peroxide (H2O2) levels. These changes correlated with an increase in serine phosphorylated catalase. Using the inhibitory peptide δV1.1, this phosphorylation was shown to be PKCδ dependent. Mass spectrometry identified serine167 as the phosphorylation site. Site-directed mutagenesis was used to generate a phospho-mimic (S167D) catalase. Activity assays using recombinant protein purified from E.coli or transiently transfected COS-7 cells, demonstrated that S167D-catalase had an increased ability to degrade H2O2 compared to the wildtype enzyme. Using a phospho-specific antibody, we were able to verify that pS167 catalase levels are modulated in lambs with acute increases in PBF in the presence and absence of the ET receptor antagonist, tezosentan. S167 is being located on the dimeric interface suggesting it could be involved in regulating the formation of catalase tetramers. To evaluate this possibility we utilized analytical gel-filtration to examine the multimeric structure of recombinant wildtype- and S167D-catalase. We found that recombinant wildtype catalase was present as a mixture of monomers and dimers while S167D catalase was primarily tetrameric. Further, the incubation of wildtype catalase with PKCδ was sufficient to convert wildtype catalase into a tetrameric structure. In conclusion, this is the first report indicating that the phosphorylation of catalase regulates its multimeric structure and activity. PMID:24211614

  20. Wood Utilization Is Dependent on Catalase Activities in the Filamentous Fungus Podospora anserina

    Science.gov (United States)

    Bourdais, Anne; Bidard, Frederique; Zickler, Denise; Berteaux-Lecellier, Veronique; Silar, Philippe; Espagne, Eric

    2012-01-01

    Catalases are enzymes that play critical roles in protecting cells against the toxic effects of hydrogen peroxide. They are implicated in various physiological and pathological conditions but some of their functions remain unclear. In order to decipher the role(s) of catalases during the life cycle of Podospora anserina, we analyzed the role of the four monofunctional catalases and one bifunctional catalase-peroxidase genes present in its genome. The five genes were deleted and the phenotypes of each single and all multiple mutants were investigated. Intriguingly, although the genes are differently expressed during the life cycle, catalase activity is dispensable during both vegetative growth and sexual reproduction in laboratory conditions. Catalases are also not essential for cellulose or fatty acid assimilation. In contrast, they are strictly required for efficient utilization of more complex biomass like wood shavings by allowing growth in the presence of lignin. The secreted CATB and cytosolic CAT2 are the major catalases implicated in peroxide resistance, while CAT2 is the major player during complex biomass assimilation. Our results suggest that P. anserina produces external H2O2 to assimilate complex biomass and that catalases are necessary to protect the cells during this process. In addition, the phenotypes of strains lacking only one catalase gene suggest that a decrease of catalase activity improves the capacity of the fungus to degrade complex biomass. PMID:22558065

  1. Catalase activity in the soil of the wood biogeocenoses in the Samara-river region

    Directory of Open Access Journals (Sweden)

    A. F. Kulik

    2009-11-01

    Full Text Available Research of catalase activity changes in connection with the free-radical oxidation is soil of natural and artificial ecosystems is conducted. The catalase is a plants’ enzyme of antioxidative protection. The catalase activity is a marker of variety and improvement of soils. It is important for the problems solutions in applied soil science. The aberrations of catalase, peroxidase and polyphenol oxidase activities characterise not only the metabolizing of plants, microorganisms and soils, but the level of the environmental pollution. The general activity of enzymatic systems allows ascertaining their role in the forming of biota components’ resistance to the exogenous influence. The seasonal dynamics of the soils’ catalase activity subject to the type of a biogeocenosis is disclosed.

  2. Catalase activity is modulated by calcium and calmodulin in detached mature leaves of sweet potato.

    Science.gov (United States)

    Afiyanti, Mufidah; Chen, Hsien-Jung

    2014-01-15

    Catalase (CAT) functions as one of the key enzymes in the scavenging of reactive oxygen species and affects the H2O2 homeostasis in plants. In sweet potato, a major catalase isoform was detected, and total catalase activity showed the highest level in mature leaves (L3) compared to immature (L1) and completely yellow, senescent leaves (L5). The major catalase isoform as well as total enzymatic activity were strongly suppressed by ethylene glycol-bis(2-aminoethylether)-N,N,N',N'-tetraacetic acid (EGTA). This inhibition could be specifically and significantly mitigated in mature L3 leaves by exogenous CaCl2, but not MgCl2 or CoCl2. EGTA also inhibited the activity of the catalase isoform in vitro. Furthermore, chlorpromazine (CPZ), a calmodulin (CAM) inhibitor, drastically suppressed the major catalase isoform as well as total enzymatic activity, and this suppression was alleviated by exogenous sweet potato calmodulin (SPCAM) fusion protein in L3 leaves. CPZ also inhibited the activity of the catalase isoform in vitro. Protein blot hybridization showed that both anti-catalase SPCAT1 and anti-calmodulin SPCAM antibodies detect a band at the same position, which corresponds to the activity of the major catalase isoform from unboiled, but not boiled crude protein extract of L3 leaves. An inverse correlation between the major catalase isoform/total enzymatic activity and the H2O2 level was also observed. These data suggest that sweet potato CAT activity is modulated by CaCl2 and SPCAM, and plays an important role in H2O2 homeostasis in mature leaves. Association of SPCAM with the major CAT isoform is required and regulates the in-gel CAT activity band. Copyright © 2013 Elsevier GmbH. All rights reserved.

  3. The utilization of some iron and zinc compounds as regulators of catalase activity at Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Efremova, N.

    2013-11-01

    Full Text Available The main aim of this study was to examine the impact of some zinc and iron compounds as oxidative stress factors on catalase activity, which is known to be important defense system of microorganisms to metal stress. For the investigation was used baker's yeast strain - Saccharomyces cerevisiae CNMN-Y-11 previously selected as a source of protein and catalase. The obtained results have revealed that compounds of iron and zinc with citrate and acetate contributes to the accumulation of yeast biomass and have beneficial effect on the catalase activity at selected yeast strain. The maximum increase of catalase activity in yeast biomass was established in case of iron and zinc citrate supplementation to the nutritive medium in optimal concentration of 15.0 mg/l. Results of the present study could be used for the elaboration of new procedures of catalase obtaining by directed synthesis with the utilization of selected metal compounds.

  4. MILICIA EXCELSA WELW CC BERG

    African Journals Online (AJOL)

    lekitos'

    infestation, while chemical control was a successful alternative. Key Words: Iroko, gall formation, screen house, Lambda-Cyhalothrin, Phytolyma. INTRODUCTION. Iroko (Milicia excelsa Welw C.C. Berg.) from. Moraceae family is a large deciduous tree that grows between 30 to 50m in height, with a diameter ranging from 1.7 ...

  5. Iridoid Glucosides from Picconia excelsa

    DEFF Research Database (Denmark)

    Damtoft, Søren; Franzyk, Henrik; Jensen, Søren Rosendal

    1997-01-01

    An investigation of the iridoids of Picconia excelsa from Tenerife provided 17 iridoid glucosides together with verbascoside. Major constituents (> 0.5%) were loganin, ketologanin, oleoacteoside and the new picconioside I-a bisiridoid consisting of loganin esterified with deoxyloganin. Minor cons...

  6. Effect of TiO₂ nanoparticles on the structure and activity of catalase.

    Science.gov (United States)

    Zhang, Hong-Mei; Cao, Jian; Tang, Bo-Ping; Wang, Yan-Qing

    2014-08-05

    TiO₂ nanoparticles are the most widely used metal oxide nanoparticles and have oxidative toxicity. Catalase is an important antioxidant enzyme. Here the understanding of an effect of TiO₂ nanoparticles on the activity and structure of catalase is crucial to characterize the toxicity of TiO₂ nanoparticles. These experimental data revealed that TiO₂ nanoparticles could bind to catalase by the electrostatic and hydrogen bonding forces. On binding TiO₂ nanoparticles, catalase got destabilized with the decrease of α-helices content, the solvent polarity of environment around the fluorescence chromophores on catalase were also affected. In addition, TiO₂ nanoparticles also affected the activity of catalase. TiO₂ nanoparticles acted as an activator of catalase activity at a low molar concentration and as an inhibitor at a higher molar concentration. With regard to human health, the present study could provide a better understanding of the potential nanotoxicity of TiO₂ nanoparticles. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  7. The Molecular Mechanism of the Catalase-like Activity in Horseradish Peroxidase.

    Science.gov (United States)

    Campomanes, Pablo; Rothlisberger, Ursula; Alfonso-Prieto, Mercedes; Rovira, Carme

    2015-09-02

    Horseradish peroxidase (HRP) is one of the most relevant peroxidase enzymes, used extensively in immunochemistry and biocatalysis applications. Unlike the closely related catalase enzymes, it exhibits a low activity to disproportionate hydrogen peroxide (H2O2). The origin of this disparity remains unknown due to the lack of atomistic information on the catalase-like reaction in HRP. Using QM(DFT)/MM metadynamics simulations, we uncover the mechanism for reduction of the HRP Compound I intermediate by H2O2 at atomic detail. The reaction begins with a hydrogen atom transfer, forming a peroxyl radical and a Compound II-like species. Reorientation of the peroxyl radical in the active site, concomitant with the transfer of the second hydrogen atom, is the rate-limiting step, with a computed free energy barrier (18.7 kcal/mol, ∼ 6 kcal/mol higher than the one obtained for catalase) in good agreement with experiments. Our simulations reveal the crucial role played by the distal pocket residues in accommodating H2O2, enabling formation of a Compound II-like intermediate, similar to catalases. However, out of the two pathways for Compound II reduction found in catalases, only one is operative in HRP. Moreover, the hydrogen bond network in the distal side of HRP compensates less efficiently than in catalases for the energetic cost required to reorient the peroxyl radical at the rate-determining step. The distal Arg and a water molecule in the "wet" active site of HRP have a substantial impact on the reaction barrier, compared to the "dry" active site in catalase. Therefore, the lower catalase-like efficiency of heme peroxidases compared to catalases can be directly attributed to the different distal pocket architecture, providing hints to engineer peroxidases with a higher rate of H2O2 disproportionation.

  8. Direct measurement of catalase activity in living cells and tissue biopsies

    Energy Technology Data Exchange (ETDEWEB)

    Scaglione, Christine N.; Xu, Qijin; Ramanujan, V. Krishnan, E-mail: Ramanujanv@csmc.edu

    2016-01-29

    Spatiotemporal regulation of enzyme-substrate interactions governs the decision-making steps in biological systems. Enzymes, being functional units of every living cell, contribute to the macromolecular stability of cell survival, proliferation and hence are vital windows to unraveling the biological complexity. Experimental measurements capturing this dynamics of enzyme-substrate interactions in real time add value to this understanding. Furthermore these measurements, upon validation in realistic biological specimens such as clinical biopsies – can further improve our capability in disease diagnostics and treatment monitoring. Towards this direction, we describe here a novel, high-sensitive measurement system for measuring diffusion-limited enzyme-substrate kinetics in real time. Using catalase (enzyme) and hydrogen peroxide (substrate) as the example pair, we demonstrate that this system is capable of direct measurement of catalase activity in vitro and the measured kinetics follows the classical Michaelis-Menten reaction kinetics. We further demonstrate the system performance by measuring catalase activity in living cells and in very small amounts of liver biopsies (down to 1 μg total protein). Catalase-specific enzyme activity is demonstrated by genetic and pharmacological tools. Finally we show the clinically-relevant diagnostic capability of our system by comparing the catalase activities in liver biopsies from young and old mouse (liver and serum) samples. We discuss the potential applicability of this system in clinical diagnostics as well as in intraoperative surgical settings. - Highlights: • A novel, direct measurement of Catalase enzyme activity via, oxygen sensing method. • Steady-stateprofiles of Catalase activity follow the Michaelis-Menten Kinetics. • Catalase-specific activity demonstrated using genetic and pharmacological tools. • Overcomes limitations of spectroscopic methods and indirect calorimetric approaches. • Clear

  9. Influence of Catalase Activity on Resistance of Coagulase-positive Staphylococci to Hydrogen Peroxide1

    Science.gov (United States)

    Amin, V. M.; Olson, N. F.

    1968-01-01

    Catalase activities of intact cells and cell-free extracts of coagulase-positive staphylococcal cultures 105B and 558D isolated from milk, culture 25042 from a clinical source, and Staphylococcus aureus 196E were determined at 32.2 C. Cultures were treated with 0.025 and 0.05% hydrogen peroxide at 37.8 and 54.4 C and without hydrogen peroxide at 54.4 C to determine the relationship between catalase activity and resistance to these treatments. The relationship held true for cultures 105B and 196E; culture 105B had the lowest catalase activity and lowest resistance to H2O2 at 37.8 C, whereas S. aureus 196E possessed a high catalase activity and was most resistant at 37.8 C. Catalase activities of cell-free extracts of cultures 25042, 558, and 196E were similar, but resistance to H2O2 at 37.8 C was greater for culture 196E. The lower resistance of culture 25042 was related to low catalase activities of whole cells of this culture, which were only one-third that of whole cells of culture 196E. Culture 558 was least resistant to heat treatment at 54.4 C and showed the greatest sensitivity to added H2O2 at this temperature. PMID:5645413

  10. Association of CAT polymorphisms with catalase activity and exposure to environmental oxidative stimuli

    Energy Technology Data Exchange (ETDEWEB)

    Nadif, R.; Mintz, M.; Jedlicka, A.; Bertrand, J.P.; Kleeberger, S.R.; Kauffmann, F. [INSERM, Villejuif (France)

    2005-12-01

    We tested the hypotheses that catalase activity is modified by CAT single nucleotide polymorphisms (SNPs) (-262;-844), and by their interactions with oxidant exposures (coal dusts, smoking), lymphotoxin alpha (LTA, Nco I) and tumor necrosis factor (TNF, -308) in 196 miners. Erythrocyte catalase, superoxide dismutase, and glutathione peroxidase activities were measured. The CAT -262 SNP was related to lower catalase activity (104, 87 and 72 k/g hemoglobin for CC, CT and TT, respectively, p {lt} 0.0001). Regardless of CAT SNPs, the LTA Nco I but not the TNF-308 SNP was associated with catalase activity (p = 0.04 and p = 0.8). CAT - 262 T carriers were less frequent in highly exposed miners (OR = 0.39 (0.20-0.78), p = 0.007). In CAT- 262 T carriers only, catalase activity decreased with high dust exposure (p = 0.01). Haplotype analyses (combined CAT SNPs) confirm these results. Results show that CAT- 262 and LTA Nco I SNPs, and interaction with coal dust exposure, influenced catalase activity.

  11. Study of root and leaf rachis of Spathelia excelsa: phytochemistry and activity against fungus Moniliophthora perniciosa associated with cupuassu (Theobroma grandiflorum); Estudo em raiz e raquis foliar de Spathelia excelsa: fitoquimica e atividade frente ao fungo Moniliophthora perniciosa associado ao cupuacuzeiro (Theobroma grandiflorum)

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Loretta Ennes de; Lima, Maria da Paz; Maximo, Ariane da Costa; Pereira, Elaine Cristina da Silva; Moreira, Wagner Alan dos Santos [Instituto Nacional de Pesquisas da Amazonia (INPA), Manaus, AM (Brazil). Coordenacao de Pesquisas em Tecnologia e Inovacao; Ferreira, Antonio Gilberto [Universidade Federal de Sao Carlos (UFSCAR), SP (Brazil). Dept. de Quimica; Veras, Solange de Mello [Universidade Federal do Amazonas (UFAM), Manaus, AM (Brazil). Fac. de Ciencias Agrarias; Souza, Maria Geralda de, E-mail: mdapaz@inpa.gov.br [Empresa Brasileira de Pesquisa Agropecuaria (EMBRAPA), Manaus, AM (Brazil)

    2012-07-01

    The chemical composition of Spathelia excelsa (Krause) R. S. Cowan and Brizicky was investigated and the limonoids harrisonin (1) and deacetylspathelin (2), alkaloids folinin and casimiroin mixture (3a,b), plus a further casimiroin (3b) were identified in methanol extract from root. The CH{sub 2}Cl{sub 2} extract from the rachis yielded protolimonoid 3{beta}-angeloyl-21,24-epoxy-7{alpha},21{alpha},23{alpha},25-tetrahydroxy-4{alpha},4{beta},8{beta},10{beta}-tetramethyl -25-dimethyl-14,18-cyclo-5{alpha},13{alpha},14{alpha},17{alpha}-cholestane (4), and methanol extract, the limonoids limonin diosphenol (5) and perforatin (6), as well as the chromone biflorin (7). Harrisonin and biflorin were isolated for the first time in this genus. On the antifungal assay against witches' broom (Moniliophthora perniciosa) compound 3b was found to be active. (author)

  12. Helicobacter Catalase Devoid of Catalytic Activity Protects the Bacterium against Oxidative Stress.

    Science.gov (United States)

    Benoit, Stéphane L; Maier, Robert J

    2016-11-04

    Catalase, a conserved and abundant enzyme found in all domains of life, dissipates the oxidant hydrogen peroxide (H2O2). The gastric pathogen Helicobacter pylori undergoes host-mediated oxidant stress exposure, and its catalase contains oxidizable methionine (Met) residues. We hypothesized catalase may play a large stress-combating role independent of its classical catalytic one, namely quenching harmful oxidants through its recyclable Met residues, resulting in oxidant protection to the bacterium. Two Helicobacter mutant strains (katAH56A and katAY339A) containing catalase without enzyme activity but that retain all Met residues were created. These strains were much more resistant to oxidants than a catalase-deletion mutant strain. The quenching ability of the altered versions was shown, whereby oxidant-stressed (HOCl-exposed) Helicobacter retained viability even upon extracellular addition of the inactive versions of catalase, in contrast to cells receiving HOCl alone. The importance of the methionine-mediated quenching to the pathogen residing in the oxidant-rich gastric mucus was studied. In contrast to a catalase-null strain, both site-change mutants proficiently colonized the murine gastric mucosa, suggesting that the amino acid composition-dependent oxidant-quenching role of catalase is more important than the well described H2O2-dissipating catalytic role. Over 100 years after the discovery of catalase, these findings reveal a new non-enzymatic protective mechanism of action for the ubiquitous enzyme. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  13. PRODUCTION of FREE RADICALS and CATALASE ACTIVITY DURING ACUTE EXERCISE TRAINING IN YOUNG MEN

    OpenAIRE

    M A.C. de Castro; Cavalcanti Neto, F. F.; L M.C Lima; da Silva, F. M.; Oliveira, R. J.; Zanesco, A

    2009-01-01

    Reactive oxygen species (ROS) are constantly produced by cells that promote cellular oxidative damage and are neutralized by an antioxidant system including superoxide dismutase, glutathione, peroxidase and catalase. Male volunteers were exercised for 20 minutes, three days (60, 70 and 80% of maximum heart rate). Catalase activity and plasma malondialdehyde concentration were measured. The mean age of the volunteers was 25 +/- 7 years, with body mass index 2 of 24.03 +/- 4.32 kg/m(2). Acute e...

  14. Electrochemical monitoring of native catalase activity in skin using skin covered oxygen electrode.

    Science.gov (United States)

    Nocchi, Sarah; Björklund, Sebastian; Svensson, Birgitta; Engblom, Johan; Ruzgas, Tautgirdas

    2017-07-15

    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 H 2 O 2 and the amperometric current response was recorded. The observed current is due to H 2 O 2 penetration through the outermost skin barrier (referred to as the stratum corneum, SC) and subsequent catalytic generation of O 2 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 H 2 O 2 penetration. Our experiments also indicate that skin contains a substantial amount of catalase, which is sufficient to detoxify H 2 O 2 that reaches the viable epidermis after exposure of skin to high concentrations of peroxide (0.5-1mM H 2 O 2 ). 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. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. UV-resistant Acinetobacter sp. isolates from Andean wetlands display high catalase activity.

    Science.gov (United States)

    Di Capua, Cecilia; Bortolotti, Ana; Farías, María Eugenia; Cortez, Néstor

    2011-04-01

    Andean wetlands are characterized by their extreme environmental conditions such as high UV radiation, elevated heavy metal content and salinity. We present here the first study on UV tolerance and antioxidant defense of four Acinetobacter strains: Ver3, Ver5 and Ver7, isolated from Lake Verde, and N40 from Lake Negra, both lakes located 4400 m above sea level. All four isolates displayed higher UV resistance compared with collection strains, with Ver3 and Ver7 being the most tolerant strains not only to UV radiation but also to hydrogen peroxide (H(2)O(2)) and methyl viologen (MV) challenges. A single superoxide dismutase band with similar activity was detected in all studied strains, whereas different electrophoretic pattern and activity levels were observed for catalase. Ver3 and Ver7 displayed 5-15 times higher catalase activity levels than the control strains. Analysis of the response of antioxidant enzymes to UV and oxidative challenges revealed a significant increase in Ver7 catalase activity after H(2)O(2) and MV exposure. Incubation of Ver7 cultures with a catalase inhibitor resulted in a significant decrease of tolerance against UV radiation. We conclude that the high catalase activity displayed by Ver7 isolate could play an important role in UV tolerance. © 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  16. Natural resistance to ascorbic acid induced oxidative stress is mainly mediated by catalase activity in human cancer cells and catalase-silencing sensitizes to oxidative stress

    Directory of Open Access Journals (Sweden)

    Klingelhoeffer Christoph

    2012-05-01

    Full Text Available Abstract Background Ascorbic acid demonstrates a cytotoxic effect by generating hydrogen peroxide, a reactive oxygen species (ROS involved in oxidative cell stress. A panel of eleven human cancer cell lines, glioblastoma and carcinoma, were exposed to serial dilutions of ascorbic acid (5-100 mmol/L. The purpose of this study was to analyse the impact of catalase, an important hydrogen peroxide-detoxifying enzyme, on the resistance of cancer cells to ascorbic acid mediated oxidative stress. Methods Effective concentration (EC50 values, which indicate the concentration of ascorbic acid that reduced the number of viable cells by 50%, were detected with the crystal violet assay. The level of intracellular catalase protein and enzyme activity was determined. Expression of catalase was silenced by catalase-specific short hairpin RNA (sh-RNA in BT-20 breast carcinoma cells. Oxidative cell stress induced apoptosis was measured by a caspase luminescent assay. Results The tested human cancer cell lines demonstrated obvious differences in their resistance to ascorbic acid mediated oxidative cell stress. Forty-five percent of the cell lines had an EC50 > 20 mmol/L and fifty-five percent had an EC50 50 of 2.6–5.5 mmol/L, glioblastoma cells were the most susceptible cancer cell lines analysed in this study. A correlation between catalase activity and the susceptibility to ascorbic acid was observed. To study the possible protective role of catalase on the resistance of cancer cells to oxidative cell stress, the expression of catalase in the breast carcinoma cell line BT-20, which cells were highly resistant to the exposure to ascorbic acid (EC50: 94,9 mmol/L, was silenced with specific sh-RNA. The effect was that catalase-silenced BT-20 cells (BT-20 KD-CAT became more susceptible to high concentrations of ascorbic acid (50 and 100 mmol/L. Conclusions Fifty-five percent of the human cancer cell lines tested were unable to protect themselves

  17. [Study of catalase and proteolytic activities of different variants of Bacillus mesentericus].

    Science.gov (United States)

    Vasilevskaya, I A; Kolchinskaya, I D; Sergeichuk, M G; Roy, A A

    1975-01-01

    Catalase and proteolytic activity of the culures and morphological variants of Bacillus mesentericus fuscus, Bac. mesentericus vulgatus were studied. The variants were obtained as a result of prolonged cultivation of the stock strains in the potato mash under the layer of vaseline oil. The level of catalase activity varies in different morphological variants of the same culture, changes with age and depends on the storage conditions. The catalase activity in the rough, smooth and papillar variants that were freshly isolated from the potato mash was 1.5=2.5 times lower than that in the variants long kept on the agar medium. The quantitative indexes of the proteolytic activity of different variants also varied.

  18. Direct measurement of catalase activity in living cells and tissue biopsies.

    Science.gov (United States)

    Scaglione, Christine N; Xu, Qijin; Ramanujan, V Krishnan

    2016-01-29

    Spatiotemporal regulation of enzyme-substrate interactions governs the decision-making steps in biological systems. Enzymes, being functional units of every living cell, contribute to the macromolecular stability of cell survival, proliferation and hence are vital windows to unraveling the biological complexity. Experimental measurements capturing this dynamics of enzyme-substrate interactions in real time add value to this understanding. Furthermore these measurements, upon validation in realistic biological specimens such as clinical biopsies - can further improve our capability in disease diagnostics and treatment monitoring. Towards this direction, we describe here a novel, high-sensitive measurement system for measuring diffusion-limited enzyme-substrate kinetics in real time. Using catalase (enzyme) and hydrogen peroxide (substrate) as the example pair, we demonstrate that this system is capable of direct measurement of catalase activity in vitro and the measured kinetics follows the classical Michaelis-Menten reaction kinetics. We further demonstrate the system performance by measuring catalase activity in living cells and in very small amounts of liver biopsies (down to 1 μg total protein). Catalase-specific enzyme activity is demonstrated by genetic and pharmacological tools. Finally we show the clinically-relevant diagnostic capability of our system by comparing the catalase activities in liver biopsies from young and old mouse (liver and serum) samples. We discuss the potential applicability of this system in clinical diagnostics as well as in intraoperative surgical settings. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Activation of Peroxisome Proliferator-Activated Receptor Alpha Improves Aged and UV-Irradiated Skin by Catalase Induction.

    Science.gov (United States)

    Shin, Mi Hee; Lee, Se-Rah; Kim, Min-Kyoung; Shin, Chang-Yup; Lee, Dong Hun; Chung, Jin Ho

    2016-01-01

    Peroxisome proliferator-activated receptor alpha (PPARα) is a nuclear hormone receptor involved in the transcriptional regulation of lipid metabolism, fatty acid oxidation, and glucose homeostasis. Its activation stimulates antioxidant enzymes such as catalase, whose expression is decreased in aged human skin. Here we investigated the expression of PPARα in aged and ultraviolet (UV)-irradiated skin, and whether PPARα activation can modulate expressions of matrix metalloproteinase (MMP)-1 and procollagen through catalase regulation. We found that PPARα mRNA level was significantly decreased in intrinsically aged and photoaged human skin as well as in UV-irradiated skin. A PPARα activator, Wy14643, inhibited UV-induced increase of MMP-1 and decrease of procollagen expression and caused marked increase in catalase expression. Furthermore, production of reactive oxygen species (ROS) was suppressed by Wy14643 in UV-irradiated and aged dermal fibroblasts, suggesting that the PPARα activation-induced upregulation of catalase leads to scavenging of ROS produced due to UV irradiation or aging. PPARα knockdown decreased catalase expression and abolished the beneficial effects of Wy14643. Topical application of Wy14643 on hairless mice restored catalase activity and prevented MMP-13 and inflammatory responses in skin. Our findings indicate that PPARα activation triggers catalase expression and ROS scavenging, thereby protecting skin from UV-induced damage and intrinsic aging.

  20. Differential activation of catalase expression and activity by PPAR agonists: Implications for astrocyte protection in anti-glioma therapy☆

    Science.gov (United States)

    Khoo, Nicholas K.H.; Hebbar, Sachin; Zhao, Weiling; Moore, Steven A.; Domann, Frederick E.; Robbins, Mike E.

    2013-01-01

    Glioma survival is dismal, in part, due to an imbalance in antioxidant expression and activity. Peroxisome proliferator-activated receptor (PPAR) agonists have antineoplastic properties which present new redox-dependent targets for glioma anticancer therapies. Herein, we demonstrate that treatment of primary cultures of normal rat astrocytes with PPAR agonists increased the expression of catalase mRNA protein, and enzymatic activity. In contrast, these same agonists had no effect on catalase expression and activity in malignant rat glioma cells. The increase in steady-state catalase mRNA observed in normal rat astrocytes was due, in part, to de novo mRNA synthesis as opposed to increased catalase mRNA stability. Moreover, pioglitazone-mediated induction of catalase activity in normal rat astrocytes was completely blocked by transfection with a PPARγ-dominant negative plasmid. These data suggest that defects in PPAR-mediated signaling and gene expression may represent a block to normal catalase expression and induction in malignant glioma. The ability of PPAR agonists to differentially increase catalase expression and activity in normal astrocytes but not glioma cells suggests that these compounds might represent novel adjuvant therapeutic agents for the treatment of gliomas. PMID:24024139

  1. Coordination modes of bridge carboxylates in dinuclear manganese compounds determine their catalase-like activities.

    Science.gov (United States)

    Jiang, Xiaojun; Liu, Hui; Zheng, Bing; Zhang, Jingyan

    2009-10-28

    To explore the role of bridge carboxylate coordination modes on the catalase-like activities of dinuclear manganese compounds, [Mn(II)2(bpmapa)2(H2O)2](ClO4)2 (1), [Mn(II)2(pbpmapa)2(H2O)2](ClO4)2 (2), and [Mn(II)2(bpmaa)2(H2O)3](ClO4)2 (3) (bpmapa = [bis(2-pyridylmethyl)amino]propionic acid, pbpmapa = alpha-phenyl-beta-[bis(2-pyridylmethyl)amino]propionic acid, and bpmaa = [bis(2-pyridylmethyl)amino]acetic acid), in which Mn(II)-Mn(II) centers have a similar coordination sphere but different carboxylate-Mn bridging modes have been synthesized and structurally characterized by single X-ray diffraction, UV-visible, IR, and EPR spectroscopies, and their catalase-like activities were investigated. Studies of their catalytic activities and the influence of the nitrogenous bases on their catalytic activities indicated that the carboxylate-Mn coordination mode was crucial in H2O2 deprotonation, and eventually in H2O2 disproportionation. Compound 1 with a bidentate carboxylate bridge showed higher catalase-like activity than 2 and 3, in which the carboxylate groups have a monodentate bridging mode. The deprotonation ability of the carboxylate anion was determined by the O-C-O angle and the distance between the weakly bound oxygen of the bridging carboxylate to the manganese ion. The smaller the angle, and the shorter the distance, the stronger the basicity that the carboxylate anion exhibits. The bidentate mu-1,1 bridging coordination mode functionally mimicked the glutamate residues at the manganese catalase active site. Our results suggested that increasing the basicity of the bridging carboxylate ligand of the catalase model compounds will increase their deprotonation ability and lead to more active catalase mimics.

  2. A comprehensive evaluation of catalase-like activity of different classes of redox-active therapeutics.

    Science.gov (United States)

    Tovmasyan, Artak; Maia, Clarissa G C; Weitner, Tin; Carballal, Sebastián; Sampaio, Romulo S; Lieb, Dominik; Ghazaryan, Robert; Ivanovic-Burmazovic, Ivana; Ferrer-Sueta, Gerardo; Radi, Rafael; Reboucas, Julio S; Spasojevic, Ivan; Benov, Ludmil; Batinic-Haberle, Ines

    2015-09-01

    Because of the increased insight into the biological role of hydrogen peroxide (H2O2) under physiological and pathological conditions and the role it presumably plays in the action of natural and synthetic redox-active drugs, there is a need to accurately define the type and magnitude of reactions that may occur with this intriguing and key species of redoxome. Historically, and frequently incorrectly, the impact of catalase-like activity has been assigned to play a major role in the action of many redox-active drugs, mostly SOD mimics and peroxynitrite scavengers, and in particular MnTBAP(3-) and Mn salen derivatives. The advantage of one redox-active compound over another has often been assigned to the differences in catalase-like activity. Our studies provide substantial evidence that Mn(III) N-alkylpyridylporphyrins couple with H2O2 in actions other than catalase-related. Herein we have assessed the catalase-like activities of different classes of compounds: Mn porphyrins (MnPs), Fe porphyrins (FePs), Mn(III) salen (EUK-8), and Mn(II) cyclic polyamines (SOD-active M40403 and SOD-inactive M40404). Nitroxide (tempol), nitrone (NXY-059), ebselen, and MnCl2, which have not been reported as catalase mimics, were used as negative controls, while catalase enzyme was a positive control. The dismutation of H2O2 to O2 and H2O was followed via measuring oxygen evolved with a Clark oxygen electrode at 25°C. The catalase enzyme was found to have kcat(H2O2)=1.5×10(6)M(-1) s(-1). The yield of dismutation, i.e., the maximal amount of O2 evolved, was assessed also. The magnitude of the yield reflects an interplay between the kcat(H2O2) and the stability of compounds toward H2O2-driven oxidative degradation, and is thus an accurate measure of the efficacy of a catalyst. The kcat(H2O2) values for 12 cationic Mn(III) N-substituted (alkyl and alkoxyalkyl) pyridylporphyrin-based SOD mimics and Mn(III) N,N'-dialkylimidazolium porphyrin, MnTDE-2-ImP(5+), ranged from 23 to 88M(-1) s

  3. Prospect of Milicia excelsa (Welw. C. Berg for Multi-Tree Species Agroforestry

    Directory of Open Access Journals (Sweden)

    Alfred Ossai Onefeli

    2015-11-01

    Full Text Available Background and Purpose: The population of most of our economically indigenous tree species in Nigeria is declining. Human activities and agricultural practices have been the ultimate contributors to this decrease. In order to ameliorate the conflict between agriculture and forestry, agroforestry was introduced. However, most of the practiced agroforestry is based on single tree species. Agroforestry practiced using single tree species have been reported to be ecologically staggered and therefore it is pertinent that phytosociology of trees with agroforestry potential is studied in order to improve the sustainability of human livelihood. Materials and Methods: This study was carried out in the University of Ibadan’s campus forest. The data were collected on Milicia excelsa (Welw. C. Berg by enumerating the tree species and also by identifying and enumerating the tree species associated with the subject tree (Milicia excelsa. Statistical analysis was done using percentages, Chi-square and charts. Results: A total of 49 individual Milicia excelsa were encountered in the study area. The results show 31 woody tree species associated with Milicia excelsa. Of all the associates Azadirachta indica A.Juss. happened to be the best one, having an average distance of 5.4 m to the subject tree. The sex ratio of Milicia excelsa was discovered to be approximately 1:1. Conclusions: Based on the obtained results of this research it may be concluded that Milicia excelsa has the prospect of being used in agroforestry in multi-tree species systems.

  4. [Pollinators of Bertholletia excelsa (Lecythidales: Lecythidaceae): interactions with stingless bees (Apidae: Meliponini) and trophic niche].

    Science.gov (United States)

    Santos, Charles F; Absy, Maria L

    2010-01-01

    This paper presents an analysis of the foraging behavior and interactions of Xylocopa frontalis Olivier (Apidae: Xylocopini) and Eulaema mocsaryi (Friese) (Apidae: Euglossini) in the presence of stingless bees (Apidae: Meliponini) in flowers of Bertholletia excelsa, the Brazilian nut. The palynological load carried by both species was also examined. This study was conducted in the farm Aruanã, Itacoatiara/ Amazonas state, Brazil, during the flowering peak of B. excelsa. The visitation by the main pollinators X. frontalis and E. mocsaryi were influenced by the presence and activities of stingless bees in the flowers of B. excelsa. Meliponini bees did not have any effect on the visits and collection of floral resources by X. frontalis, while negatively affecting the number of visits by E. mocsaryi. The stingless bees presented a variety of strategies to get access to pollen grains of B. excelsa, grouped into two categories: opportunism -Frieseomelitta trichocerata Moure, Tetragona goettei (Friese), and Tetragona kaieteurensis (Schwarz), and stealing -Trigona branneri Cockerell, Trigona fuscipennis Friese, and Trigona guianae Cockerell. The palynological analysis from X. frontalis showed that the bee collected pollen in a few species of plants, but mainly on B. excelsa. The pollen grains of B. excelsa were poorly represented in the pollen shipments of E. mocsaryi, due to its large trophic niche in the locality.

  5. Decrease in catalase activity of Folsomia candida fed a Bt rice diet

    DEFF Research Database (Denmark)

    Yuan, Yiyang; Ke, Xin; Chen, Fajun

    2011-01-01

    Here we report the effects of three Bt-rice varieties and their non-Bt conventional isolines on biological traits including survival, reproduction, and the activities of three antioxidant enzymes superoxide dismutase, catalase and peroxidase, in the Collembolan, Folsomia candida. The reproduction...... was significantly lower when fed Kemingdao and Huahui1 than those feeding on their non-GM near-isogenic varieties Xiushui and Minghui63 respectively, this can be explained by the differences of plant compositions depended on variety of rice. The catalase activity of F. candida was significantly lower when fed...

  6. Catalase activity as a potential indicator of the reducer component of small closed ecosystems

    Science.gov (United States)

    Sarangova, A. B.; Somova, L. A.; Pisman, T. I.

    1997-01-01

    Dynamics of catalase activity has been shown to reflect the growth curve of microorganisms in batch cultivation (celluloselythic bacteria Bacillus acidocaldarius and bacteria of the associated microflora Chlorella vulgaris). Gas and substrate closure of the three component ecosystems with spatially separated components ``producer-consumer-reducer'' (Chl. vulgaris-Paramecium caudatum-B. acidocaldarius, two bacterial strains isolated from the associated microflora Chl. vulgaris) demonstrated that the functioning of the reducer component can be estimated by the catalase activity of microorganisms of this component.

  7. Natural resistance to ascorbic acid induced oxidative stress is mainly mediated by catalase activity in human cancer cells and catalase-silencing sensitizes to oxidative stress

    Science.gov (United States)

    2012-01-01

    Background Ascorbic acid demonstrates a cytotoxic effect by generating hydrogen peroxide, a reactive oxygen species (ROS) involved in oxidative cell stress. A panel of eleven human cancer cell lines, glioblastoma and carcinoma, were exposed to serial dilutions of ascorbic acid (5-100 mmol/L). The purpose of this study was to analyse the impact of catalase, an important hydrogen peroxide-detoxifying enzyme, on the resistance of cancer cells to ascorbic acid mediated oxidative stress. Methods Effective concentration (EC50) values, which indicate the concentration of ascorbic acid that reduced the number of viable cells by 50%, were detected with the crystal violet assay. The level of intracellular catalase protein and enzyme activity was determined. Expression of catalase was silenced by catalase-specific short hairpin RNA (sh-RNA) in BT-20 breast carcinoma cells. Oxidative cell stress induced apoptosis was measured by a caspase luminescent assay. Results The tested human cancer cell lines demonstrated obvious differences in their resistance to ascorbic acid mediated oxidative cell stress. Forty-five percent of the cell lines had an EC50 > 20 mmol/L and fifty-five percent had an EC50 ascorbic acid was observed. To study the possible protective role of catalase on the resistance of cancer cells to oxidative cell stress, the expression of catalase in the breast carcinoma cell line BT-20, which cells were highly resistant to the exposure to ascorbic acid (EC50: 94,9 mmol/L), was silenced with specific sh-RNA. The effect was that catalase-silenced BT-20 cells (BT-20 KD-CAT) became more susceptible to high concentrations of ascorbic acid (50 and 100 mmol/L). Conclusions Fifty-five percent of the human cancer cell lines tested were unable to protect themselves against oxidative stress mediated by ascorbic acid induced hydrogen peroxide production. The antioxidative enzyme catalase is important to protect cancer cells against cytotoxic hydrogen peroxide

  8. Development of a new catalase activity assay for biological samples using optical CUPRAC sensor.

    Science.gov (United States)

    Bekdeşer, Burcu; Özyürek, Mustafa; Güçlü, Kubilay; Alkan, Fulya Üstün; Apak, Reşat

    2014-11-11

    A novel catalase activity assay was developed for biological samples (liver and kidney tissue homogenates) using a rapid and low-cost optical sensor-based 'cupric reducing antioxidant capacity' (CUPRAC) method. The reagent, copper(II)-neocuproine (Cu(II)-Nc) complex, was immobilized onto a cation-exchanger film of Nafion, and the absorbance changes associated with the formation of the highly-colored Cu(I)-Nc chelate as a result of reaction with hydrogen peroxide (H2O2) was measured at 450 nm. When catalase was absent, H2O2 produced the CUPRAC chromophore, whereas catalase, being an effective H2O2 scavenger, completely annihilated the CUPRAC signal due to H2O2. Thus, the CUPRAC absorbance due to H2O2 oxidation concomitant with Cu(I)-Nc formation decreased proportionally with catalase. The developed sensor gave a linear response over a wide concentration range of H2O2 (0.68-78.6 μM). This optical sensor-based method applicable to tissue homogenates proved to be efficient for low hydrogen peroxide concentrations (physiological and nontoxic levels) to which the widely used UV method is not accurately responsive. Thus, conventional problems of the UV method arising from relatively low sensitivity and selectivity, and absorbance disturbance due to gaseous oxygen evolution were overcome. The catalase findings of the proposed method for tissue homogenates were statistically alike with those of HPLC. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Relationship between uptake of mercury vapor by mushrooms and its catalase activity

    Energy Technology Data Exchange (ETDEWEB)

    Ogata, M.; Kenmotsu, K.; Hirota, N.; Naito, M.

    1981-12-01

    The uptake of mercury vapor by mushrooms (Shiitake) artifically grown on an oak tree and the uptake in vitro by catalase extracts prepared from mushroom Hay Bacillus and spinach are reported. Mushrooms were exposed to 1.4 mg/Hg/cu m for 11 days. Measurement of total mercury was as previously described (Ogata et al. 1978, 1979). Levels in mushrooms ranged from 0.4 +/- 0.1 ..mu..g/g at 0.5 days to 4.6 +/- 0.2 ..mu..g/g at 10.5 days and steady-state thereafter. In in vitro studies Hy uptake by mushroom catalase extract was estimated by the perborate method. Uptake was found to parallel catalase activity and was inhibited by potassium cyanide, sodium azide, and 3-amino-1,2,4-triazole. Similar results were obtained with Hay Bacillus and spinach catalase extracts. Results suggest that the level of mercury in the mushroom can be used as an indicator of mercury pollution in the environment. It is also suggested that catalase has an important role in uptake of mercury vapor in the plant. 2 tables (JMT)

  10. A manganese catalase from Thermomicrobium roseum with peroxidase and catecholase activity.

    Science.gov (United States)

    Baginski, Robin; Sommerhalter, Monika

    2017-01-01

    An enzyme with catechol oxidase activity was identified in Thermomicrobium roseum extracts via solution assays and activity-stained SDS-PAGE. Yet, the genome of T. roseum does not harbor a catecholase gene. The enzyme was purified with two anion exchange chromatography steps and ultimately identified to be a manganese catalase with additional peroxidase and catecholase activity. Catalase activity (6280 ± 430 IU/mg) clearly dominated over pyrogallol peroxidase (231 ± 53 IU/mg) and catecholase (3.07 ± 0.56 IU/mg) activity as determined at 70 °C. Most enzyme kinetic properties were comparable to previously characterized manganese catalase enzymes. Catalase activity was highest at alkaline pH values and showed inhibition by excess substrate and chloride. The apparent K m and k cat values were 20 mM and 2.02 × 104 s-1 subunit-1 at 25 °C and pH 7.0.

  11. Computational study concerning the effect of some pesticides on the Proteus Mirabilis catalase activity

    Science.gov (United States)

    Isvoran, Adriana

    2016-03-01

    Assessment of the effects of the herbicides nicosulfuron and chlorsulfuron and the fungicides difenoconazole and drazoxlone upon catalase produced by soil microorganism Proteus mirabilis is performed using the molecular docking technique. The interactions of pesticides with the enzymes are predicted using SwissDock and PatchDock docking tools. There are correlations for predicted binding energy values for enzyme-pesticide complexes obtained using the two docking tools, all the considered pesticides revealing favorable binding to the enzyme, but only the herbicides bind to the catalytic site. These results suggest the inhibitory potential of chlorsulfuron and nicosulfuron on the catalase activity in soil.

  12. The Review of Certain In Vivo Antioxidant Effects on Essential Oils of Origanum Minutiflorum O Schwarz-Ph Davis, Juniperus Excelsa Bieb.subsp. Excelsa and Histopathologic Changes

    Directory of Open Access Journals (Sweden)

    I Göze

    Full Text Available ABSTRACT Essential oil of plants called Juniperus excelsa Bieb. (JE, Origanum minutiflorum O. Schwarz and P.H. Davis (OM were used in this study. In order to determine experimental doses, LD50 values of essential oils were determined on mice. Taking into consideration the LD30 range, the experimental toxic doses were calculated for each rat (rat/kg. The toxic dosages thus determined were adapted to rats for active substances (rat/kg. Using commercially available pure virgin olive oil (VOO as the solvent and diluting agent, OM oil (n=10, JE fruitoil (n=10, carvacrol (CRV (n=10, VOO (n=10 and normal saline SF (n=8 were administered on the basis of 12 days into intraperitoneal (IP. Enzyme activities of Glucose-6-Phosphate dehydrogenase (G6PDH, malate dehydrogenase (MDH, Superoxide Dismutase (SOD, Glutathione-S-transferase (GST, Adenosine-deaminase (ADA and Catalase were studied in isolates of kidney, brain and liver tissues. The data was statistically analyzed through Kruskal Wallis variance analysis. Elevated levels of GST and catalase have been found statistically important, as have both essential oil activities of OM and JE in the kidney tissue (p<0.005. All of the enzymes except the levels of ADA and SOD led to a statistically significant change in the brain and liver. There was sinusoidal hyperemia and capsular adhesion in the liver as histopathological were found to be statistically significant (p<0.005. It did not observe any important changes in the other organs. Findings were scored and analyzed by using x2(chi-square test and Fisher’s definite variance analysis.

  13. Decrease in catalase activity of Folsomia candida fed a Bt rice diet

    Energy Technology Data Exchange (ETDEWEB)

    Yuan Yiyang, E-mail: yuanyy@ioz.ac.cn [State Key Laboratory of Integrated Management of Pest and Rodents, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing 100101 (China); Graduate School, Chinese Academy of Sciences, Beijing 100039 (China); Ke Xin, E-mail: xinke@sibs.ac.cn [Shanghai Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 300 Fenglin Road, Shanghai 200032 (China); Chen Fajun, E-mail: fajunchen@njau.edu.cn [College of Plant Protection, Department of Entomology, Nanjing Agricultural University, Nanjing 210095 (China); Krogh, Paul Henning, E-mail: phk@dmu.dk [Department of Bioscience, University of Aarhus, P.O. Box 314, Vejlsoevej 25, DK-8600 Silkeborg (Denmark); Ge Feng, E-mail: gef@ioz.ac.cn [State Key Laboratory of Integrated Management of Pest and Rodents, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing 100101 (China)

    2011-12-15

    Here we report the effects of three Bt-rice varieties and their non-Bt conventional isolines on biological traits including survival, reproduction, and the activities of three antioxidant enzymes superoxide dismutase, catalase and peroxidase, in the Collembolan, Folsomia candida. The reproduction was significantly lower when fed Kemingdao and Huahui1 than those feeding on their non-GM near-isogenic varieties Xiushui and Minghui63 respectively, this can be explained by the differences of plant compositions depended on variety of rice. The catalase activity of F. candida was significantly lower when fed the Bt-rice variety Kemingdao compared to the near-isogenic non-Bt-rice variety Xiushui. This suggests that some Bt-rice varieties may impose environmental stress to collembolans. We emphasize that changes in activity of antioxidant enzymes of non-target organisms are important in understanding the ecological consequences for organisms inhabiting transgenic Bt-rice plantations. - Highlights: > We examine the effects of Bt-rice on Folsomia candida with laboratory test. > The reproduction of F. candida was decreased by two Bt-rice varieties. > Decreased reproduction caused by the differences of varieties or C/N ratio of rice. > The catalase activity was decreased by Bt-rice Kemingdao. > Some Bt-rice may impose environmental stress on NTOs. - The catalase of the collembolan (Folsomia candida) was decreased when fed Bt-rice, Kemingdao.

  14. Catalase activity of cassava (Manihot esculenta) plant under African ...

    African Journals Online (AJOL)

    aghomotsegin

    The virus impacts stress on the cellular metabolism of the plant producing a lot of reactive oxygen species and increases the expression of the antioxidant enzymes. The activity of ... Several items of foods are processed from cassava, examples are: fufu .... enzymes denatured) to remove the effects of the color of the extract.

  15. Ozone Sensitivity and Catalase Activity in Pigmented and Non-Pigmented Strains of Serratia Marcescens

    Science.gov (United States)

    de Ondarza, José

    2017-01-01

    Background: Ozone exposure rapidly leads to bacterial death, making ozone an effective disinfectant in food industry and health care arena. However, microbial defenses may moderate this effect and play a role in the effective use of oxidizing agents for disinfection. Serratia marcescens is an opportunistic pathogen, expressing genes differentially during infection of a human host. A better understanding of regulatory systems that control expression of Serratia’s virulence genes and defenses is therefore valuable. Objective: Here, we investigated the role of pigmentation and catalase in Serratia marcescens on survival to ozone exposure. Method: Pigmented and non-pigmented strains of Serratia marcescens were cultured to exponential or stationary phase and exposed to 5 ppm of gaseous ozone for 2.5 – 10 minutes. Survival was calculated via plate counts. Catalase activity was measured photometrically and tolerance to hydrogen peroxide was assayed by disk-diffusion. Results: Exposure of S. marcescens to 5 ppm gaseous ozone kills > 90% of cells within 10 minutes in a time and concentration-dependent manner. Although pigmented Serratia (grown at 28°C) survived ozonation better than unpigmented Serratia (grown at 35°C), non-pigmented mutant strains of Serratia had similar ozone survival rates, catalase activity and H2O2 tolerance as wild type strains. Rather, ozone survival and catalase activity were elevated in 6 hour cultures compared to 48 hour cultures. Conclusion: Our studies did not bear out a role for prodigiosin in ozone survival. Rather, induction of oxidative stress responses during exponential growth increased both catalase activity and ozone survival in both pigmented and unpigmented S. marcescens. PMID:28567147

  16. Hydrogen peroxide homeostasis: activation of plant catalase by calcium/calmodulin

    Science.gov (United States)

    Yang, T.; Poovaiah, B. W.

    2002-01-01

    Environmental stimuli such as UV, pathogen attack, and gravity can induce rapid changes in hydrogen peroxide (H(2)O(2)) levels, leading to a variety of physiological responses in plants. Catalase, which is involved in the degradation of H(2)O(2) into water and oxygen, is the major H(2)O(2)-scavenging enzyme in all aerobic organisms. A close interaction exists between intracellular H(2)O(2) and cytosolic calcium in response to biotic and abiotic stresses. Studies indicate that an increase in cytosolic calcium boosts the generation of H(2)O(2). Here we report that calmodulin (CaM), a ubiquitous calcium-binding protein, binds to and activates some plant catalases in the presence of calcium, but calcium/CaM does not have any effect on bacterial, fungal, bovine, or human catalase. These results document that calcium/CaM can down-regulate H(2)O(2) levels in plants by stimulating the catalytic activity of plant catalase. Furthermore, these results provide evidence indicating that calcium has dual functions in regulating H(2)O(2) homeostasis, which in turn influences redox signaling in response to environmental signals in plants.

  17. KatB, a cyanobacterial Mn-catalase with unique active site configuration: Implications for enzyme function.

    Science.gov (United States)

    Bihani, Subhash C; Chakravarty, Dhiman; Ballal, Anand

    2016-04-01

    Manganese catalases (Mn-catalases), a class of H2O2 detoxifying proteins, are structurally and mechanistically distinct from the commonly occurring catalases, which contain heme. Active site of Mn-catalases can serve as template for the synthesis of catalase mimetics for therapeutic intervention in oxidative stress related disorders. However, unlike the heme catalases, structural aspects of Mn-catalases remain inadequately explored. The genome of the ancient cyanobacterium Anabaena PCC7120, shows the presence of two Mn-catalases, KatA and KatB. Here, we report the biochemical and structural characterization of KatB. The KatB protein (with a C-terminal his-tag) was over-expressed in Escherichia coli and purified by affinity chromatography. On the addition of Mn(2+) to the E. coli growth medium, a substantial increase in production of the soluble KatB protein was observed. The purified KatB protein was an efficient catalase, which was relatively insensitive to inhibition by azide. Crystal structure of KatB showed a hexameric assembly with four-helix bundle fold, characteristic of the Ferritin-like superfamily. With canonical Glu4His2 coordination geometry and two terminal water ligands, the KatB active site was distinctly different from that of other Mn-catalases. Interestingly, the KatB active site closely resembled the active sites of ruberythrin/bacterioferritin, bi-iron members of the Ferritin-like superfamily. The KatB crystal structure provided fundamental insights into the evolutionary relationship within the Ferritin-like superfamily and further showed that Mn-catalases can be sub-divided into two groups, each with a distinct active site configuration. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Evaluation of herbal ointment formulation of Milicia excelsa (Welw ...

    African Journals Online (AJOL)

    The wound healing effect of Milicia excelsa ointment was evaluated in three groups of rats using the excision wound model. Also the antibacterial effect of M. excelsa extract on Pseudomonas aeruginosa and Staphylococcus aureus was investigated. The result of the study showed that the ointment of M. excelsa significantly ...

  19. Changes in gene expression and catalase activity in Oryza sativa L. under abiotic stress.

    Science.gov (United States)

    Vighi, I L; Benitez, L C; do Amaral, M N; Auler, P A; Moraes, G P; Rodrigues, G S; da Maia, L C; Pinto, L S; Braga, E J B

    2016-11-03

    Different rice (Oryza sativa L.) genotypes were subjected to high salinity and low temperature (150 mM NaCl and 13°C, respectively) for 0, 6, 24, 48, or 72 h. We evaluated the simultaneous expression of the genes OsCATA, OsCATB, and OsCATC, correlated gene expression with enzyme activity, and verified the regulation of these genes through identification of cis-elements in the promoter region. The hydrogen peroxide content increased in a tolerant genotype and decreased in a sensitive genotype under both stress conditions. Lipid peroxidation increased in the tolerant genotype when exposed to cold, and in the sensitive genotype when exposed to high salinity. Catalase activity significantly increased in both genotypes when subjected to 13°C. In the tolerant genotype, OsCATA and OsCATB were the most responsive to high salinity and cold, while in the sensitive genotype, OsCATA and OsCATC responded positively to saline stress, as did OsCATA and OsCATB to low temperature. Cis-element analysis identified different regulatory sequences in the catalase promoter region of each genotype. The sensitive genotype maintained a better balance between hydrogen oxyacid levels, catalase activity, and lipid peroxidation under low temperature than the resistant genotype. OsCATA and OsCATB were the most responsive in the salt-tolerant genotype to cold, OsCATA and OsCATC were the most responsive to saline stress, and OsCATA and OsCATB were the most responsive to chilling stress in the sensitive genotype. There were positive correlations between catalase activity and OsCATB expression in the tolerant genotype under saline stress and in the sensitive genotype under cold stress.

  20. A Laboratory Experiment Investigating Different Aspects of Catalase Activity in an Inquiry - Based Approach

    Science.gov (United States)

    Kimbrough, Doris R.; Magoun, Mary Ann; Langfur, Meg

    1997-02-01

    The action of the enzyme catalase on aqueous hydrogen peroxide to generate oxygen gas is a well-established demonstration (1-3). Catalase is typically obtained by aqueous extraction of a potato, and the potato extract is mixed together with 3% hydrogen peroxide. The oxygen that is produced can be collected over water. Variations on the procedure can demonstrate the dependence of catalytic activity on temperature or the presence of inhibitors (1, 2). The University of Colorado at Denver has used a version of this procedure as a laboratory in its second-semester course for nonmajors. Recently, students have been allowed to expand upon the procedures prescribed in the laboratory handout in an open-ended project format. We explored some of these variations in detail, and the results provided here offer ideas, centered around this laboratory, for open-ended projects that can be used in an inquiry-based approach.

  1. Murine and human b locus pigmentation genes encode a glycoprotein (gp75) with catalase activity

    Energy Technology Data Exchange (ETDEWEB)

    Halaban, R.; Moellmann, G. (Yale Univ. School of Medicine, New Haven, CT (USA))

    1990-06-01

    Melanogenesis is regulated in large part by tyrosinase, and defective tyrosinase leads to albinism. The mechanisms for other pigmentation determinants (e.g., those operative in tyrosinase-positive albinism and in murine coat-color mutants) are not yet known. One murine pigmentation gene, the brown (b) locus, when mutated leads to a brown (b/b) or hypopigmentated (B{sup lt}/B{sup lt}) coat versus the wild-type black (B/B). The authors show that the b locus codes for a glycoprotein with the activity of a catalase (catalase B). Only the c locus protein is a tyrosinase. Because peroxides may be by-products of melanogenic activity and hydrogen peroxide in particular is known to destroy melanin precursors and melanin, they conclude that pigmentation is controlled not only by tyrosinase but also by a hydroperoxidase. The studies indicate that catalase B is identical with gp75, a known human melanosomal glycoprotein; that the b mutation is in a heme-associated domain; and that the B{sup lt} mutation renders the protein susceptible to rapid proteolytic degradation.

  2. Effect of Ethylene on the Increase in Catalase Activity through Microbody Development in Wounded Sweet Potato Root Tissue

    OpenAIRE

    Muneharu, ESAKA; Takeshi, TAKAHASHI; Tadashi, Asahi; Laboratory of Biochemistry, Faculty of Agriculture, Nagoya University

    1983-01-01

    Catalase activity increases when slices of sweet potato root tissue are incubated in air. The increase is due to de novo synthesis of the enzyme protein and probably also to activation of a precursor protein [Esaka et al. (1983) Plant & Cell Physiol. 24: 615]. The activity-increase was partly depressed when tissue slices were incubated in ethylene-containing air, while the immunologically determined amount of catalase protein did not increase, rather it decreased, under the same conditions. W...

  3. A Catalase-related Hemoprotein in Coral Is Specialized for Synthesis of Short-chain Aldehydes: DISCOVERY OF P450-TYPE HYDROPEROXIDE LYASE ACTIVITY IN A CATALASE.

    Science.gov (United States)

    Teder, Tarvi; Lõhelaid, Helike; Boeglin, William E; Calcutt, Wade M; Brash, Alan R; Samel, Nigulas

    2015-08-07

    In corals a catalase-lipoxygenase fusion protein transforms arachidonic acid to the allene oxide 8R,9-epoxy-5,9,11,14-eicosatetraenoic acid from which arise cyclopentenones such as the prostanoid-related clavulones. Recently we cloned two catalase-lipoxygenase fusion protein genes (a and b) from the coral Capnella imbricata, form a being an allene oxide synthase and form b giving uncharacterized polar products (Lõhelaid, H., Teder, T., Tõldsepp, K., Ekins, M., and Samel, N. (2014) PloS ONE 9, e89215). Here, using HPLC-UV, LC-MS, and NMR methods, we identify a novel activity of fusion protein b, establishing its role in cleaving the lipoxygenase product 8R-hydroperoxy-eicosatetraenoic acid into the short-chain aldehydes (5Z)-8-oxo-octenoic acid and (3Z,6Z)-dodecadienal; these primary products readily isomerize in an aqueous medium to the corresponding 6E- and 2E,6Z derivatives. This type of enzymatic cleavage, splitting the carbon chain within the conjugated diene of the hydroperoxide substrate, is known only in plant cytochrome P450 hydroperoxide lyases. In mechanistic studies using (18)O-labeled substrate and incubations in H2(18)O, we established synthesis of the C8-oxo acid and C12 aldehyde with the retention of the hydroperoxy oxygens, consistent with synthesis of a short-lived hemiacetal intermediate that breaks down spontaneously into the two aldehydes. Taken together with our initial studies indicating differing gene regulation of the allene oxide synthase and the newly identified catalase-related hydroperoxide lyase and given the role of aldehydes in plant defense, this work uncovers a potential pathway in coral stress signaling and a novel enzymatic activity in the animal kingdom. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  4. Highly Active and Stable Large Catalase Isolated from a Hydrocarbon Degrading Aspergillus terreus MTCC 6324

    Directory of Open Access Journals (Sweden)

    Preety Vatsyayan

    2016-01-01

    Full Text Available A hydrocarbon degrading Aspergillus terreus MTCC 6324 produces a high level of extremely active and stable cellular large catalase (CAT during growth on n-hexadecane to combat the oxidative stress caused by the hydrocarbon degrading metabolic machinery inside the cell. A 160-fold purification with specific activity of around 66 × 105 U mg−1 protein was achieved. The native protein molecular mass was 368 ± 5 kDa with subunit molecular mass of nearly 90 kDa, which indicates that the native CAT protein is a homotetramer. The isoelectric pH (pI of the purified CAT was 4.2. BLAST aligned peptide mass fragments of CAT protein showed its highest similarity with the catalase B protein from other fungal sources. CAT was active in a broad range of pH 4 to 12 and temperature 25°C to 90°C. The catalytic efficiency (Kcat/Km of 4.7 × 108 M−1 s−1 within the studied substrate range and alkaline pH stability (half-life, t1/2 at pH 12~15 months of CAT are considerably higher than most of the extensively studied catalases from different sources. The storage stability (t1/2 of CAT at physiological pH 7.5 and 4°C was nearly 30 months. The haem was identified as haem b by electrospray ionization tandem mass spectroscopy (ESI-MS/MS.

  5. Catalase activity of IgG antibodies from the sera of healthy donors and patients with schizophrenia.

    Science.gov (United States)

    Ermakov, Evgeny A; Smirnova, Ludmila P; Bokhan, Nikolay A; Semke, Arkadiy V; Ivanova, Svetlana A; Buneva, Valentina N; Nevinsky, Georgy A

    2017-01-01

    We present first evidence showing that some electrophoretically homogeneous IgGs from the sera of patients with schizophrenia (36.4%) and their Fab and F(ab)2 fragments as well as from healthy donors (33.3%) possess catalase activity. The relative catalase activity of IgGs from the sera of individual schizophrenia patients (and healthy donors) significantly varied from patient to patient, but the activity of IgGs from healthy donors is on average 15.8-fold lower than that for schizophrenia patients. After extensive dialysis of purified IgGs against EDTA chelating metal ions, the relative catalase activity of IgGs decreases on average approximately 2.5-3.7-fold; all IgGs possess metal-dependent and independent catalase activity. The addition of external Me2+ ions to dialyzed and non-dialyzed IgGs leads to a significant increase in their activity. The best activator of dialyzed and non-dialyzed IgGs is Co2+, the activation by Cu2+, Mn2+, and Ni2+ ions were rare and always lower than by Co2+. Every IgG preparation demonstrates several individual sets of very well expressed pH optima in the pH range from 4.0 to 9.5. These data speak for the individual repertoire of catalase IgGs in every person and an extreme diversity of abzymes in their pH optima and activation by different metal ions. It is known that antioxidant enzymes such as superoxide dismutases, catalases, and glutathione peroxidases represent critical defense mechanisms preventing oxidative modifications of DNA, proteins, and lipids. Catalase activity of human IgGs could probably also play a major role in the protection of organisms from oxidative stress and toxic compounds.

  6. Expression and Enzyme Activity of Catalase in Chilo suppressalis (Lepidoptera: Crambidae) Is Responsive to Environmental Stresses.

    Science.gov (United States)

    Lu, Yanhui; Bai, Qi; Zheng, Xusong; Lu, Zhongxian

    2017-08-01

    Catalase (CAT) is an important antioxidant enzyme that protects organisms against oxidative stresses by eliminating hydrogen peroxide. In this study, we cloned and characterized a full-length cDNA of CAT from Chilo suppressalis (CsCAT) and examined the influence of environmental stresses on CsCAT expression and enzyme activity. The cDNA contains a 1659-bp open reading frame encoding a polypeptide of 553 amino acids most closely related (90.14%) to Papilio polytes catalases. The CsCAT was expressed in all developmental stages with the highest expression in the fat body, and the CsCAT enzyme activity closely mirrored its observed mRNA expression patterns. The CsCAT mRNA was up-regulated when the larvae were exposed to high temperature (≥30 °C), insecticides (abamectin and chlorantraniliprole), chemicals (H2O2, CHP, CdCl2, and CuSO4), and a dead-end trap plant (vetiver grass), and the CsCAT enzyme activity again mirrored the observed CsCAT expression patterns. These results suggest that up-regulation of CsCAT may enhance the defense response of C. suppressalis by weakening the effects of environmental stresses, and provide insight into the role of CsCAT during development of C. suppressalis. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  7. Catalase activity of different Candida species after exposition to specific antiserum Atividade de catalase em Candida sp. após exposição a antisoro específico

    Directory of Open Access Journals (Sweden)

    Natália R.S. Miyasaka

    2008-03-01

    Full Text Available Antisera were developed in rabbits after challenge with intracellular antigens of Candida albicans, C. tropicalis and C. parapsilosis. Microorganism catalase has been correlated with virulence, resistance to drugs and immunogenicity. The intracellular catalase is consistently present in strains of Candida and in this paper, the enzyme activity was analysed by PAGE after exposition to antisera. The catalases of C. albicans, C. parapsilosis and C. tropicalis were immunogenic and differed in their binding to specific antibodies raised in rabbits. Tests of cross-reactivity between different Candida species showed that when antiserum from C. albicans immunized rabbit was incubated with intracellular extracts of these three Candida species, the catalases activities were abolished. However, the antisera from C. parapsilosis or C. tropicalis immunized rabbits did not affect the catalase activity of C. albicans; the enzyme of C. albicans was inactivated only by the antiserum to the catalase of own C. albicans. The antiserum to the catalase of C. tropicalis was species-specific and did not cross-react with catalases of C. albicans and C. parapsilosis. The activities of Aspergillus niger and bovine catalases were not affected by the antiserum from any Candida immunized rabbits. This report is a preliminary study of specific antisera that react against intracellular catalase of Candida sp. and neutralize the enzymatic activity. Further study is necessary to develop species-specific antibody once differences in the susceptibility of the Candida species to commonly used antifungal drugs make identification to the species level important.Antisoros foram desenvolvidos em animais em resposta à injeção de antígenos intracelulares de Candida albicans, C. tropicalis e C. parapsilosis. A presença de catalase nos microrganismos tem sido relacionada à virulência, resistência a drogas e imunogenicidade. A catalase intracelular está sempre presente nas cepas de

  8. Dynamics of erythrocyte count, hemoglobin, and catalase activity in rat blood in hypokinesia, muscular activity and restoration

    Science.gov (United States)

    Taneyeva, G. V.; Potapovich, G. M.; Voloshko, N. A.; Uteshev, A. B.

    1980-01-01

    Tests were conducted to prove that muscular exertion (in this instance swimming) of different duration and intensity, as well as hypodynamia, result in an increase of hemoglobin and number of red blood cells in peripheral blood rats. Catalase activity increased with an increase in the duration of swimming, but only up to 6 hr; with 7-9 hr of swimming as well as in hypodynamia, catalase activity decreased. It was also observed that under hypodynamia as well as in 3, 5 and 6 hr exertion (swimming) the color index of blood decreased. Pressure chamber treatment (for 8 min each day for one week), alternating a 2 min negative pressure up to 35 mm Hg with 1 min positive pressure, increased the erythrocyte count and hemoglobin content.

  9. Down-regulation of catalase activity allows transient accumulation of a hydrogen peroxide signal in Chlamydomonas reinhardtii.

    Science.gov (United States)

    Michelet, Laure; Roach, Thomas; Fischer, Beat B; Bedhomme, Mariette; Lemaire, Stéphane D; Krieger-Liszkay, Anja

    2013-06-01

    In photosynthetic organisms, excess light is a stress that induces production of reactive oxygen species inside the chloroplasts. As a response, the capacity of antioxidative defence mechanisms increases. However, when cells of Chlamydomonas reinhardtii were shifted from dark to high light, a reversible partial inactivation of catalase activity was observed, which correlated with a transient increase in the level of H2 O2 in the 10 μm range. This concentration range seems to be necessary to activate H2 O2 -dependent signalling pathways stimulating the expression of H2 O2 responsive genes, such as the heat shock protein HSP22C. Catalase knock-down mutants had lost the transient accumulation of H2 O2 , suggesting that a decrease in catalase activity was the key element for establishing a transient H2 O2 burst. Catalase was inactivated by a one-electron event consistent with the reduction of a single cysteine. We propose that under high light intensity, the redox state of the photosynthetic electron transport chain is sensed and transmitted to the cytosol to regulate the catalase activity. This allows a transient accumulation of H2 O2 , inducing a signalling event that is transmitted to the nucleus to modulate the expression of chloroplast-directed protection enzymes. © 2012 Blackwell Publishing Ltd.

  10. Unprecedented access of phenolic substrates to the heme active site of a catalase: substrate binding and peroxidase-like reactivity of Bacillus pumilus catalase monitored by X-ray crystallography and EPR spectroscopy.

    Science.gov (United States)

    Loewen, Peter C; Villanueva, Jacylyn; Switala, Jacek; Donald, Lynda J; Ivancich, Anabella

    2015-05-01

    Heme-containing catalases and catalase-peroxidases catalyze the dismutation of hydrogen peroxide as their predominant catalytic activity, but in addition, individual enzymes support low levels of peroxidase and oxidase activities, produce superoxide, and activate isoniazid as an antitubercular drug. The recent report of a heme enzyme with catalase, peroxidase and penicillin oxidase activities in Bacillus pumilus and its categorization as an unusual catalase-peroxidase led us to investigate the enzyme for comparison with other catalase-peroxidases, catalases, and peroxidases. Characterization revealed a typical homotetrameric catalase with one pentacoordinated heme b per subunit (Tyr340 being the axial ligand), albeit in two orientations, and a very fast catalatic turnover rate (kcat  = 339,000 s(-1) ). In addition, the enzyme supported a much slower (kcat  = 20 s(-1) ) peroxidatic activity utilizing substrates as diverse as ABTS and polyphenols, but no oxidase activity. Two binding sites, one in the main access channel and the other on the protein surface, accommodating pyrogallol, catechol, resorcinol, guaiacol, hydroquinone, and 2-chlorophenol were identified in crystal structures at 1.65-1.95 Å. A third site, in the heme distal side, accommodating only pyrogallol and catechol, interacting with the heme iron and the catalytic His and Arg residues, was also identified. This site was confirmed in solution by EPR spectroscopy characterization, which also showed that the phenolic oxygen was not directly coordinated to the heme iron (no low-spin conversion of the Fe(III) high-spin EPR signal upon substrate binding). This is the first demonstration of phenolic substrates directly accessing the heme distal side of a catalase. © 2015 Wiley Periodicals, Inc.

  11. The effect of low LET (Linear Energy Transfer ionizing radiation to catalase activity of Wistar’s submandibular gland

    Directory of Open Access Journals (Sweden)

    Nevy Triditha Putri

    2016-12-01

    Full Text Available Intraoral periapical radiograph examination is the additional examination which is the most widely used in Dentistry. This radiograph examination using an x-ray ionizing radiation with low LET (Linear Energy Transfer, and may affect submandibular salivary gland. Ionizing radiation exposure can cause damage by inducing a series of changes at the molecular and cellular level. This study aimed to prove the effects of x-ray ionizing radiation with low LET towards the catalase activity of Rattus norvegicus strain Wistar’s submandibular gland. The subjects were 28 male Wistar rats and divided into 4 groups (n=7. Three groups were exposed 4, 8 and 14 times to radiation with 0.002 µSv for each exposure. The catalase activity of each rat was examined by a spectrophotometer. Data were analyzed using one-way ANOVA followed by Bonferroni test. The results showed the average of catalase activity on Wistar rat’s submandibular gland, respectively for: 0.150±0.0895 (KK, 0.1405±0.0607 (K1, 0.1228±0.0290 (K2, 0.1227±0.0556 (K3. Data showed significant differences of catalase activity between test groups, but showed not significant differences of catalase activity between each groups of Rattus norvegicus strain Wistar’s submandibular gland. In this study concluded decreased catalase activity of Rattus norvegicus strain Wistar’s submandibular gland resulting from x-rays ionizing radiation by 4 times, 8 times and 14 times exposures.

  12. Effect of phenol on germination capacity and polyphenol oxidase, peroxidase and catalase activities in lettuce

    Directory of Open Access Journals (Sweden)

    Tadić Vojin

    2014-01-01

    Full Text Available In this study we examined the activities of polyphenol oxidase (PPO and antioxidant enzymes, peroxidase (POX and catalase (CAT during lettuce seed germination at different concentrations of phenol. Out of eleven varieties of lettuce, four were chosen according to their germination tolerance to phenol as follows: plants exhibiting high (Ljubljanska ledenka - LJL and Nansen - N and low toleranace (Little Gem - LG and Majska kraljica - MK. A decrease in germination efficiency after exposure to LD50 of phenol was determined for these four varieties. The effects of phenol treatment on POX, CAT and PPO activities were determined after 4, 5, 6, 7 and 8 days of growth at LD50 concentrations. A trend of increased peroxidase activity was observed in seeds grown on LD50 of phenol compared to control seeds. A significant increase in CAT activity was observed at the beginning of treatment for MK, LG and N in seeds grown on phenol as well as in control seeds. A trend of increased PPO activity was observed in all control seeds. We also investigated the affinity of PPO for two different substrates that were used for the determination of enzyme activity. Our results show that LJL and N are the varieties most tolerant to growth on phenol. Here we report on the activities of their antioxidant enzymes and PPO during seed germination. [Projekat Ministarstva nauke Republike Srbije, br. ON173017

  13. Isolation of volatile compounds of Aloe excelsa (Berger)

    African Journals Online (AJOL)

    hope&shola

    2010-10-25

    Oct 25, 2010 ... carried out on Aloe ferox, Aloe vera as well as A. excelsa. (Speranza et al., 1986, 1990; Koyama et al., 1994; Eloff,. 1998; Amabeoku et al., 1998; Dagne, 2000; Coopoosamy and Magwa 2007). This investigation deals with the isola- tion of volatile compounds present in the leaf exudates of. A. excelsa.

  14. Activity of catalase adsorbed to carbon nanotubes: effects of carbon nanotube surface properties.

    Science.gov (United States)

    Zhang, Chengdong; Luo, Shuiming; Chen, Wei

    2013-09-15

    Nanomaterials have been studied widely as the supporting materials for enzyme immobilization. However, the interactions between enzymes and carbon nanotubes (CNT) with different morphologies and surface functionalities may vary, hence influencing activities of the immobilized enzyme. To date how the adsorption mechanisms affect the activities of immobilized enzyme is not well understood. In this study the adsorption of catalase (CAT) on pristine single-walled carbon nanotubes (SWNT), oxidized single-walled carbon nanotubes (O-SWNT), and multi-walled carbon nanotubes (MWNT) was investigated. The adsorbed enzyme activities decreased in the order of O-SWNT>SWNT>MWNT. Fourier transforms infrared spectroscopy (FTIR) and circular dichrois (CD) analyses reveal more significant loss of α-helix and β-sheet of MWNT-adsorbed than SWNT-adsorbed CAT. The difference in enzyme activities between MWNT-adsorbed and SWNT-adsorbed CAT indicates that the curvature of surface plays an important role in the activity of immobilized enzyme. Interestingly, an increase of β-sheet content was observed for CAT adsorbed to O-SWNT. This is likely because as opposed to SWNT and MWNT, O-SWNT binds CAT largely via hydrogen bonding and such interaction allows the CAT molecule to maintain the rigidity of enzyme structure and thus the biological function. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Combined effects of water temperature and copper ion concentration on catalase activity in Crassostrea ariakensis

    Science.gov (United States)

    Wang, Hui; Yang, Hongshuai; Liu, Jiahui; Li, Yanhong; Liu, Zhigang

    2015-07-01

    A central composite experimental design and response surface method were used to investigate the combined effects of water temperature (18-34°C) and copper ion concentration (0.1-1.5 mg/L) on the catalase (CAT) activity in the digestive gland of Crassostrea ariakensis. The results showed that the linear effects of temperature were significant ( P0.05), and the quadratic effects of copper ion concentration were significant ( P0.05), and the effect of temperature was greater than that of copper ion concentration. A model equation of CAT enzyme activity in the digestive gland of C. ariakensis toward the two factors of interest was established, with R 2, Adj. R 2 and Pred. R 2 values as high as 0.943 7, 0.887 3 and 0.838 5, respectively. These findings suggested that the goodness of fit to experimental data and predictive capability of the model were satisfactory, and could be practically applied for prediction under the conditions of the study. Overall, the results suggest that the simultaneous variation of temperature and copper ion concentration alters the activity of the antioxidant enzyme CAT by modulating active oxygen species metabolism, which may be utilized as a biomarker to detect the effects of copper pollution.

  16. Induction of hsp70, hsp90, and catalase activity in planarian Dugesia japonica exposed to cadmium.

    Science.gov (United States)

    Zhang, Xiufang; Mo, Yehua; Zhou, Luming; Wang, Yinan; Wang, Zhongchen; Zhao, Bosheng

    2016-08-01

    The hsp70 and hsp90 expression patterns and catalase (CAT) activity in the freshwater planaria Dugesia japonica exposed to cadmium (Cd) under laboratory conditions were investigated. Planaria were exposed to a range of Cd concentrations (0-150 μg Cd/L) for 24 h. The expression levels of hsp70 and hsp90 were determined by relative quantitative real-time polymerase chain reaction. Within the overall dose range in the experiment, the expression level of hsp70 and the activity of CAT in D. japonica were altered significantly. Hsp70 was induced in D. japonica upon Cd exposure concentrations as low as 9.375 μg Cd/L. No significant effect on the expression level of hsp90 was observed. Our findings demonstrated that stress gene hsp70, but not hsp90, was responsive to Cd contamination in D. japonica CAT activity was significantly induced at concentrations of 18.75, 37.5, and 75 μg Cd/L after 24-h exposure. We recommend that the use of hsp70 as a biomarker should be complemented by evidence of changes in other parameters, such as CAT activity, in D. japonica. © The Author(s) 2014.

  17. A Catalase-related Hemoprotein in Coral Is Specialized for Synthesis of Short-chain Aldehydes: DISCOVERY OF P450-TYPE HYDROPEROXIDE LYASE ACTIVITY IN A CATALASE

    National Research Council Canada - National Science Library

    Teder, Tarvi; Lõhelaid, Helike; Boeglin, William E; Calcutt, Wade M; Brash, Alan R; Samel, Nigulas

    2015-01-01

    In corals a catalase-lipoxygenase fusion protein transforms arachidonic acid to the allene oxide 8R,9-epoxy-5,9,11,14-eicosatetraenoic acid from which arise cyclopentenones such as the prostanoid-related clavulones...

  18. Erythrocyte Catalase Activity in More Frequent Microcytic Hypochromic Anemia: Beta-Thalassemia Trait and Iron Deficiency Anemia

    Directory of Open Access Journals (Sweden)

    Sandra Stella Lazarte

    2015-01-01

    Full Text Available Most common microcytic hypochromic anemias are iron deficiency anemia (IDA and β-thalassemia trait (BTT, in which oxidative stress (OxS has an essential role. Catalase causes detoxification of H2O2 in cells, and it is an indispensable antioxidant enzyme. The study was designed to measure erythrocyte catalase activity (ECAT in patients with IDA (10 or BTT (21, to relate it with thalassemia mutation type (β0 or β+ and to compare it with normal subjects (67. Ninety-eight individuals were analyzed since September 2013 to June 2014 in Tucumán, Argentina. Total blood count, hemoglobin electrophoresis at alkaline pH, HbA2, catalase, and iron status were performed. β-thalassemic mutations were determined by real-time PCR. Normal range for ECAT was 70,0–130,0 MU/L. ECAT was increased in 14% (3/21 of BTT subjects and decreased in 40% (4/10 of those with IDA. No significant difference (p=0,245 was shown between normal and BTT groups, while between IDA and normal groups the difference was proved to be significant (p=0,000. In β0 and β+ groups, no significant difference (p=0,359 was observed. An altered ECAT was detected in IDA and BTT. These results will help to clarify how the catalase activity works in these anemia types.

  19. Piper betle shows antioxidant activities, inhibits MCF-7 cell proliferation and increases activities of catalase and superoxide dismutase

    Directory of Open Access Journals (Sweden)

    Abrahim Noor

    2012-11-01

    Full Text Available Abstract Background Breast cancer is the most common form of cancer and the focus on finding chemotherapeutic agents have recently shifted to natural products. Piper betle is a medicinal plant with various biological activities. However, not much data is available on the anti-cancer effects of P. betle on breast cancer. Due to the current interest in the potential effects of antioxidants from natural products in breast cancer treatment, we investigated the antioxidant activities of the leaves of P. betle and its inhibitory effect on the proliferation of the breast cancer cell line, MCF-7. Methods The leaves of P. betle were extracted with solvents of varying polarities (water, methanol, ethyl acetate and hexane and their phenolic and flavonoid content were determined using colorimetric assays. Phenolic composition was characterized using HPLC. Antioxidant activities were measured using FRAP, DPPH, superoxide anion, nitric oxide and hyroxyl radical scavenging assays. Biological activities of the extracts were analysed using MTT assay and antioxidant enzyme (catalase, superoxide dismutase, glutathione peroxidase assays in MCF-7 cells. Results Overall, the ethyl acetate extract showed the highest ferric reducing activity and radical scavenging activities against DPPH, superoxide anion and nitric oxide radicals. This extract also contained the highest phenolic content implying the potential contribution of phenolics towards the antioxidant activities. HPLC analyses revealed the presence of catechin, morin and quercetin in the leaves. The ethyl acetate extract also showed the highest inhibitory effect against the proliferation of MCF-7 cells (IC50=65 μg/ml. Treatment of MCF-7 cells with the plant extract increased activities of catalase and superoxide dismutase. Conclusions Ethyl acetate is the optimal solvent for the extraction of compounds with antioxidant and anti-proliferative activities. The increased activities of catalase and superoxide

  20. Arabidopsis ABI5 plays a role in regulating ROS homeostasis by activating CATALASE 1 transcription in seed germination.

    Science.gov (United States)

    Bi, Chao; Ma, Yu; Wu, Zhen; Yu, Yong-Tao; Liang, Shan; Lu, Kai; Wang, Xiao-Fang

    2017-05-01

    It has been known that ABA INSENSITIVE 5 (ABI5) plays a vital role in regulating seed germination. In the present study, we showed that inhibition of the catalase activity with 3-amino-1,2,4-triazole (3-AT) inhibits seed germination of Col-0, abi5 mutants and ABI5-overexpression transgenic lines. Compared with Col-0, the seeds of abi5 mutants showed more sensitive to 3-AT during seed germination, while the seeds of ABI5-overexpression transgenic lines showed more insensitive. H 2 O 2 showed the same effect on seed germination of Col-0, abi5 mutants and ABI5-overexpression transgenic lines as 3-AT. These results suggest that ROS is involved in the seed germination mediated by ABI5. Further, we observed that T-DNA insertion mutants of the three catalase members in Arabidopsis displayed 3-AT-insensitive or -hypersensitive phenotypes during seed germination, suggesting that these catalase members regulate ROS homeostasis in a highly complex way. ABI5 affects reactive oxygen species (ROS) homeostasis by affecting CATALASE expression and catalase activity. Furthermore, we showed that ABI5 directly binds to the CAT1 promoter and activates CAT1 expression. Genetic evidence supports the idea that CAT1 functions downstream of ABI5 in ROS signaling during seed germination. RNA-sequencing analysis indicates that the transcription of the genes involved in ROS metabolic process or genes responsive to ROS stress is impaired in abi5-1 seeds. Additionally, expression changes in some genes correlative to seed germination were showed due to the change in ABI5 expression under 3-AT treatment. Together, all the findings suggest that ABI5 regulates seed germination at least partly by affecting ROS homeostasis.

  1. Effect of soil contamination with azadirachtin on dehydrogenase and catalase activity of soil

    Directory of Open Access Journals (Sweden)

    Rıdvan Kızılkaya

    2012-07-01

    Full Text Available nsecticides are used in modern agriculture in large quantities to control pests and increase crop yield. Their use, however, has resulted in the disruption of ecosystems because of the effects on non-target soil microorganisms, some environmental problems, and decreasing soil fertility. These negative effects of synthetic pesticides on the environment have led to the search for alternative means of pest control. One such alternative is use of natural plant products such as azadirachtin that have pesticidal activity. The aim of this experiment was to study the effect of soil contamination by azadirachtin (C35H44O16 on dehydrogenase (DHA and catalase activity (CA of soil under field conditions in Perm, Russia. The tests were conducted on loamy soil (pHH2O 6.7, ECH2O 0.213 dSm-1, organic carbon 0.99%, to which the following quantities of azadirachtin were added: 0, 15, 30 and 60 mL da-1 of soil. Experimental design was randomized plot design with three replications. The DHA and CA analyses were performed 7, 14 and 21 days after the field experiment was established. The results of field experiment showed that azadirachtin had a positive influence on the DHA and CA at different soil sampling times. The increased doses of azadirachtin applied resulted in the higher level of DHA and CA in soil. The soil DHA and CA showed the highest activity on the 21th day after 60 mL azadirachtin da-1 application doses.

  2. Effects of paraoxonase, arylesterase, ceruloplasmin, catalase, and myeloperoxidase activities on prognosis in pediatric patients with sepsis.

    Science.gov (United States)

    Ayar, Ganime; Atmaca, Yasemin Men; Alışık, Murat; Erel, Özcan

    2017-05-01

    The present study aimed to investigate the levels of paraoxonase (PON), stimulated paraoxonase (SPON), arylesterase (ARE), ceruloplasmin (CLP), myeloperoxidase (MPO), and catalase (CAT) in pediatric sepsis and to explore their effects on the prognosis of sepsis. Patients diagnosed with sepsis (n=33) and healthy controls (n=30) were included. PON, SPON, ARE, CLP, MPO, and CAT activities were measured in the sepsis and control groups. Additionally, the parameters were compared between survivors and non-survivors in the sepsis group. The levels of hemoglobin, white blood cell, platelet, lactate, and C-reactive protein were measured in the blood samples drawn from the patients with sepsis at diagnosis, at the 48th hour, and on day 7. The pediatric risk of mortality and pediatric logistic organ dysfunction scores of the patients were used for the estimation of severity of disease. Lower ARE (153.24 vs. 264.32U/L; psepsis group as compared to the control group. There was no difference between the groups in terms of PON or SPON levels. No difference was determined between the survivors and non-survivors in terms of any of the parameters. The present study determined that ARE, CLP, CAT, and MPO levels are different between the pediatric patients with sepsis and healthy controls. ARE level can be a potent biomarker for sepsis in critical patients in intensive care units. Further studies with larger samples are required to demonstrate the value of these parameters as prognostic biomarkers in pediatric sepsis. Copyright © 2017 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

  3. Catalase and glutathione peroxidase are equally active in detoxification of hydrogen peroxide in human erythrocytes

    Energy Technology Data Exchange (ETDEWEB)

    Gaetani, G.F.; Galiano, S.; Canepa, L.; Ferraris, A.M.; Kirkman, H.N.

    1989-01-01

    Genetic deficiencies of glucose-6-phosphate dehydrogenase (G6PD) and NADPH predispose affected erythrocytes to destruction from peroxides. Conversely, genetic deficiencies of catalase do not predispose affected erythrocytes to peroxide-induced destruction. These observations have served to strengthen the assumption that the NADPH/glutathione/glutathione peroxidase pathway is the principal means for disposal of H/sub 2/O/sub 2/ in human erythrocytes. Recently, however, mammalian catalase was found to have tightly bound NADPH and to require NADPH for the prevention and reversal of inactivation by its toxic substrate (H/sub 2/O/sub 2/). Since both catalase and the glutathione pathway are dependent on NADPH for function, this finding raises the possibility that both mechanisms destroy H/sub 2/O/sub 2/ in human erythrocytes. A comparison of normal and acatalasemic erythrocytes in the present study indicated that catalase accounts for more than half of the destruction of H/sub 2/O/sub 2/ when H/sub 2/O/sub 2/ is generated at a rate comparable to that which leads to hemolysis in G6PD- deficient erythrocytes.

  4. The regulation of catalase activity by PPAR gamma is affected by alpha-synuclein

    NARCIS (Netherlands)

    Yakunin, Eugenia; Kisos, Haya; Kulik, Willem; Grigoletto, Jessica; Wanders, Ronald J. A.; Sharon, Ronit

    2014-01-01

    Objective: While evidence for oxidative injury is frequently detected in brains of humans affected by Parkinson's disease (PD) and in relevant animal models, there is uncertainty regarding its cause. We tested the potential role of catalase in the oxidative injury that characterizes PD. Methods:

  5. Not so monofunctional-a case of thermostable Thermobifida fusca catalase with peroxidase activity

    NARCIS (Netherlands)

    Lončar, Nikola; Fraaije, Marco W

    Thermobifida fusca is a mesothermophilic organism known for its ability to degrade plant biomass and other organics, and it was demonstrated that it represents a rich resource of genes encoding for potent enzymes for biocatalysis. The thermostable catalase from T. fusca has been cloned and

  6. Do Superoxide Dismutase (SOD) and Catalase (CAT) protect Cells from DNA Damage Induced by Active Arsenicals?

    Science.gov (United States)

    Superoxide dismutase (SOD) catalyzes the conversion of superoxide to hydrogen peroxide, which can be converted to water and oxygen through the action of catalase. Heterozygous mice of strain B6: 129S7-SodltmlLeb/J were obtained from Jackson Laboratories and bred to produce offspr...

  7. Effects of Soy-Germ Protein on Catalase Activity of Plasma and Erythocyte of Metabolic Syndrome Women

    Directory of Open Access Journals (Sweden)

    Hery Winarsi

    2015-01-01

    Full Text Available Oxidative stress always accompany patients with metabolic syndrome (MS. Several researchers reported that soy-protein is able to decrease oxidative stress level. However, there is no report so far about soy-germ protein in relation to its potential to the decrease oxidative stress level of MS patients. The aim of this study was to explore the potential of soy-germ protein on activity of catalase enzyme in blood’s plasma as well as erythrocytes of MS patients. Double-blind randomized clinical trial was used as an experimental study. Thirty respondents were included in this study with MS, normal level blood sugar, low-HDL cholesterol but high in triglyceride, 40-65 years old, Body Mass Index > 25 kg/m2, live in Purwokerto and agreed to sign the informed consent. They were randomly grouped into 3 different groups, 10 each: Group I, was given special milk that contains soy-germ protein and Zn; Group II, soy-germ protein, while Group III was placebo; for two consecutive months. Data were taken from blood samples in 3 different periods i.e. 0, 1, and 2 months after treatment. Two months after treatment, there was an increase from 5.36 to 20.17 IU/mg (P = 0.028 in activity of catalase enzyme in blood’s plasma respondents who consumed milk containing soy-germ protein with or without Zn. A similar trend of catalase activity, but at a lower level, was also noticed in erythrocyte; which increased from 88.31 to 201.11 IU/mg (P = 0.013. The increase in activity of catalase enzyme in blood’s plasma was 2.2 times higher than that in erythrocytes.

  8. Effects of Soy-Germ Protein on Catalase Activity of Plasma and Erythocyte of Metabolic Syndrome Women

    Directory of Open Access Journals (Sweden)

    HERY WINARSI

    2015-01-01

    Full Text Available Oxidative stress always accompany patients with metabolic syndrome (MS. Several researchers reported that soy-protein is able to decrease oxidative stress level. However, there is no report so far about soy-germ protein in relation to its potential to the decrease oxidative stress level of MS patients. The aim of this study was to explore the potential of soy-germ protein on activity of catalase enzyme in blood's plasma as well as erythrocytes of MS patients. Double-blind randomized clinical trial was used as an experimental study. Thirty respondents were included in this study with MS, normal level blood sugar, low-HDL cholesterol but high in triglyceride, 40-65 years old, Body Mass Index > 25 kg/m2, live in Purwokerto and agreed to sign the informed consent. They were randomly grouped into 3 different groups, 10 each: Group I, was given special milk that contains soy-germ protein and Zn; Group II, soy-germ protein, while Group III was placebo; for two consecutive months. Data were taken from blood samples in 3 different periods i.e. 0, 1, and 2 months after treatment. Two months after treatment, there was an increase from 5.36 to 20.17 IU/mg (P = 0.028 in activity of catalase enzyme in blood's plasma respondents who consumed milk containing soy-germ protein with or without Zn. A similar trend of catalase activity, but at a lower level, was also noticed in erythrocyte; which increased from 88.31 to 201.11 IU/mg (P = 0.013. The increase in activity of catalase enzyme in blood's plasma was 2.2 times higher than that in erythrocytes.

  9. Influence of the lead ions and low dose radiation on the catalase activity in the maize germinant

    Directory of Open Access Journals (Sweden)

    O. M. Vasilyuk

    2006-02-01

    Full Text Available The experimental results of changes of the catalase activity in the maize germinants under the influence of the lead ions and low doses of radiation separately and simultaneously are presented. The consentration of the lead was 1 · 10 – 4 M and the radiation dozes were 2, 5, 10, and 15 R.

  10. On the enzymatic activity of catalase : an iron L-edge X-ray absorption study of the active centre

    NARCIS (Netherlands)

    Bergmann, Nora; Bonhommeau, Sebastien; Lange, Kathrin M.; Greil, Stefanie M.; Eisebitt, Stefan; de Groot, Frank|info:eu-repo/dai/nl/08747610X; Chergui, Majed; Aziz, Emad F.

    2010-01-01

    Catalase and methaemoglobin have very similar haem groups, which are both ferric, yet catalase decomposes hydrogen peroxide to water and oxygen very efficiently, while methaemoglobin does not. Structural studies have attributed this behaviour to their different distal environments. Here we present

  11. Effects of sub-inhibitory concentrations of German chamomile (Matricaria recotita extracts on the activity of catalase enzyme of S. aureus

    Directory of Open Access Journals (Sweden)

    gholamreza Goudarzi

    2005-12-01

    Findings: The extract showed growth inhibitory effect at dilution of and at dilution of showed bactericidal effect on standard strain. Dilutions of and as sub-inhibitory concentrations, decreased catalase activity prominently. Conclusion: Significant decrease of catalase activity at sub-inhibitory concentrations of this extract shows that this extract affects the production of catalase at different levels such as transcription, translation or transport and etc. Therefore, it is necessary to further study this extract. This enzyme can be a new target for production of novel antimicrobial agents.

  12. Modulatory effect of pineapple peel extract on lipid peroxidation,catalase activity and hepatic biomarker levels in blood plasma of alcoholinduced oxidative stressed rats

    National Research Council Canada - National Science Library

    Okafor OY Erukainure OL Ajiboye JA Adejobi RO Owolabi FO Kosoko SB

    2011-01-01

    Objective:To investigate the ability of the methanolic extract of pineapple peel to modulate alcohol-induced lipid peroxidation,changes in catalase activities and hepatic biochemical marker levels in blood...

  13. Modulatory effect of pineapple peel extract on lipid peroxidation, catalase activity and hepatic biomarker levels in blood plasma of alcohol-induced oxidative stressed rats

    National Research Council Canada - National Science Library

    Okafor, O Y; Erukainure, O l; Ajiboye, J A; Adejobi, R O; Owolabi, F O; Kosoko, S B

    2011-01-01

    To investigate the ability of the methanolic extract of pineapple peel to modulate alcohol-induced lipid peroxidation, changes in catalase activities and hepatic biochemical marker levels in blood plasma...

  14. EPR spectroscopy and catalase activity of manganese-bound DNA-binding protein from nutrient starved cells.

    Science.gov (United States)

    Hayden, Joshua Allen; Hendrich, Michael P

    2010-06-01

    DNA-binding proteins from nutrient-starved cells (DPS) protect cells from oxidative stress by removing H(2)O(2) and iron. A new class of DPS-like proteins has recently been identified, with DPS-like protein from Sulfolobus solfataricus (SsDPS) being the best characterized to date. SsDPS protects cells from oxidative stress and is upregulated in response to H(2)O(2) but also in response to iron depletion. The ferroxidase active site of SsDPS is structurally similar to the active sites of manganese catalase and rat liver arginase. The present work shows that the ferroxidase center in SsDPS binds two Mn(2+) ions with K (D) = (1/K (1) K (2))(1/2) = 48(3) microM. The binding constant of the second Mn(2+) is significantly higher than that of the first, inducing dinuclear Mn(II) cluster formation for all but the lowest concentrations of added Mn(2+). In competition experiments, equimolar amounts of Fe(2+) were unable to displace the bound manganese. EPR spectroscopy of the Mn(2) (2+) cluster showed signals comparable to those of other characterized dimanganese clusters. The exchange coupling for the cluster was determined, J = -1.4(3) cm(-1) (H = -2JS (1) S (2)), and is within the range expected for a mu(1,1)-carboxylato bridge between the manganese ions. Manganese-bound SsDPS showed catalase activity at a rate 10-100 times slower than for manganese catalases. EPR spectra of SsDPS after addition of H(2)O(2) showed the appearance of an intermediate in the reaction with H(2)O(2).

  15. Characterization of partially purified catalase from camel ( Camelus ...

    African Journals Online (AJOL)

    The liver of camel has high level of catalase (32,225 units/g tissue) as commercially used bovine liver catalase. For the establishment of the enzyme, the rate of catalase activity was linearly increased with increase of the catalase concentration and incubation time. The procedure of partial purification of catalase from camel ...

  16. In vitro effect of inorganic pollutants used in agriculture on the catalase activity of the alga Pseudokirchneriella subcapitata

    OpenAIRE

    Duarte, Silvana; Amaral Sobrinho, Nelson Moura Brasil; Jonsson, Cláudio Martín; Jokl,Lieselotte

    2014-01-01

    The effect of pollutants in particular ecosystems can be verifi ed by their action on primary producers such as the alga Pseudokirchneriella subcapitata (Korshikov) F.Hindák (Chlorophyceae), which is widely distributed in freshwater and in the soil. The effects of eight metallic ions used in agriculture – aluminum, cadmium, lead, magnesium, manganese, mercury, selenium and zinc on the enzymatic activity in P. subcapitata were investigated, using catalase as a biochemical marker. Aluminum, lea...

  17. Effect of N+ Beam Exposure on Superoxide Dismutase and Catalase Activities and Induction of Mn-SOD in Deinococcus Radiodurans

    Science.gov (United States)

    Song, Dao-jun; Chen, Ruo-lei; Shao, Chun-lin; Wu, Li-jun; Yu, Zeng-liang

    2000-10-01

    Though bacteria of the radiation-resistant Deinococcus radiodurans have a high resistance to the lethal and mutagenic effects of many DNA-damaging agents, the mechanisms involved in the response of these bacteria to oxidative stress are poorly understood. In this report, the superoxide dismutase (SOD) and catalase (CAT) activities produced by these bacteria were measured, and the change of SOD and CAT activities by 20 keV N+ beam exposure was examined. Their activities were increased by N+ beam exposure from 8×1014 ions/cm2 to 6×1015 ions/cm2. The treatment of H2O2 and [CHCl3 +CH3CH2OH] and the measurement of absorption spectrum showed that the increase in SOD activity was resulted from inducible activities of Mn-SOD in D. radiodurans AS1.633 by N+ beam exposure. These results suggested that this bacteria possess inducible defense mechanisms against the deleterious effects of oxidization.

  18. Catalase activity is stimulated by H2O2 in rich culture medium and is required for H2O2 resistance and adaptation in yeast

    Directory of Open Access Journals (Sweden)

    Dorival Martins

    2014-01-01

    Full Text Available Catalases are efficient scavengers of H2O2 and protect cells against H2O2 stress. Examination of the H2O2 stimulon in Saccharomyces cerevisiae revealed that the cytosolic catalase T (Ctt1 protein level increases 15-fold on H2O2 challenge in synthetic complete media although previous work revealed that deletion of the CCT1 or CTA1 genes (encoding peroxisomal/mitochondrial catalase A does not increase the H2O2 sensitivity of yeast challenged in phosphate buffer (pH 7.4. This we attributed to our observation that catalase activity is depressed when yeast are challenged with H2O2 in nutrient-poor media. Hence, we performed a systematic comparison of catalase activity and cell viability of wild-type yeast and of the single catalase knockouts, ctt1∆ and cta1∆, following H2O2 challenge in nutrient-rich medium (YPD and in phosphate buffer (pH 7.4. Ctt1 but not Cta1 activity is strongly induced by H2O2 when cells are challenged in YPD but suppressed when cells are challenged in buffer. Consistent with the activity results, exponentially growing ctt1∆ cells in YPD are more sensitive to H2O2 than wild-type or cta1∆ cells, whereas in buffer all three strains exhibit comparable H2O2 hypersensitivity. Furthermore, catalase activity is increased during adaptation to sublethal H2O2 concentrations in YPD but not in buffer. We conclude that induction of cytosolic Ctt1 activity is vital in protecting yeast against exogenous H2O2 but this activity is inhibited by H2O2 when cells are challenged in nutrient-free media.

  19. Catalase activity is stimulated by H2O2 in rich culture medium and is required for H2O2 resistance and adaptation in yeast☆

    Science.gov (United States)

    Martins, Dorival; English, Ann M.

    2014-01-01

    Catalases are efficient scavengers of H2O2 and protect cells against H2O2 stress. Examination of the H2O2 stimulon in Saccharomyces cerevisiae revealed that the cytosolic catalase T (Ctt1) protein level increases 15-fold on H2O2 challenge in synthetic complete media although previous work revealed that deletion of the CCT1 or CTA1 genes (encoding peroxisomal/mitochondrial catalase A) does not increase the H2O2 sensitivity of yeast challenged in phosphate buffer (pH 7.4). This we attributed to our observation that catalase activity is depressed when yeast are challenged with H2O2 in nutrient-poor media. Hence, we performed a systematic comparison of catalase activity and cell viability of wild-type yeast and of the single catalase knockouts, ctt1∆ and cta1∆, following H2O2 challenge in nutrient-rich medium (YPD) and in phosphate buffer (pH 7.4). Ctt1 but not Cta1 activity is strongly induced by H2O2 when cells are challenged in YPD but suppressed when cells are challenged in buffer. Consistent with the activity results, exponentially growing ctt1∆ cells in YPD are more sensitive to H2O2 than wild-type or cta1∆ cells, whereas in buffer all three strains exhibit comparable H2O2 hypersensitivity. Furthermore, catalase activity is increased during adaptation to sublethal H2O2 concentrations in YPD but not in buffer. We conclude that induction of cytosolic Ctt1 activity is vital in protecting yeast against exogenous H2O2 but this activity is inhibited by H2O2 when cells are challenged in nutrient-free media. PMID:24563848

  20. Catalase activity is stimulated by H(2)O(2) in rich culture medium and is required for H(2)O(2) resistance and adaptation in yeast.

    Science.gov (United States)

    Martins, Dorival; English, Ann M

    2014-01-01

    Catalases are efficient scavengers of H2O2 and protect cells against H2O2 stress. Examination of the H2O2 stimulon in Saccharomyces cerevisiae revealed that the cytosolic catalase T (Ctt1) protein level increases 15-fold on H2O2 challenge in synthetic complete media although previous work revealed that deletion of the CCT1 or CTA1 genes (encoding peroxisomal/mitochondrial catalase A) does not increase the H2O2 sensitivity of yeast challenged in phosphate buffer (pH 7.4). This we attributed to our observation that catalase activity is depressed when yeast are challenged with H2O2 in nutrient-poor media. Hence, we performed a systematic comparison of catalase activity and cell viability of wild-type yeast and of the single catalase knockouts, ctt1∆ and cta1∆, following H2O2 challenge in nutrient-rich medium (YPD) and in phosphate buffer (pH 7.4). Ctt1 but not Cta1 activity is strongly induced by H2O2 when cells are challenged in YPD but suppressed when cells are challenged in buffer. Consistent with the activity results, exponentially growing ctt1∆ cells in YPD are more sensitive to H2O2 than wild-type or cta1∆ cells, whereas in buffer all three strains exhibit comparable H2O2 hypersensitivity. Furthermore, catalase activity is increased during adaptation to sublethal H2O2 concentrations in YPD but not in buffer. We conclude that induction of cytosolic Ctt1 activity is vital in protecting yeast against exogenous H2O2 but this activity is inhibited by H2O2 when cells are challenged in nutrient-free media.

  1. Cardiac-specific overexpression of catalase prevents diabetes-induced pathological changes by inhibiting NF-κB signaling activation in the heart.

    Science.gov (United States)

    Cong, Weitao; Ruan, Dandan; Xuan, Yuanhu; Niu, Chao; Tao, Youli; Wang, Yang; Zhan, Kungao; Cai, Lu; Jin, Litai; Tan, Yi

    2015-12-01

    Catalase is an antioxidant enzyme that specifically catabolizes hydrogen peroxide (H2O2). Overexpression of catalase via a heart-specific promoter (CAT-TG) was reported to reduce diabetes-induced accumulation of reactive oxygen species (ROS) and further prevent diabetes-induced pathological abnormalities, including cardiac structural derangement and left ventricular abnormity in mice. However, the mechanism by which catalase overexpression protects heart function remains unclear. This study found that activation of a ROS-dependent NF-κB signaling pathway was downregulated in hearts of diabetic mice overexpressing catalase. In addition, catalase overexpression inhibited the significant increase in nitration levels of key enzymes involved in energy metabolism, including α-oxoglutarate dehydrogenase E1 component (α-KGD) and ATP synthase α and β subunits (ATP-α and ATP-β). To assess the effects of the NF-κB pathway activation on heart function, Bay11-7082, an inhibitor of the NF-κB signaling pathway, was injected into diabetic mice, protecting mice against the development of cardiac damage and increased nitrative modifications of key enzymes involved in energy metabolism. In conclusion, these findings demonstrated that catalase protects mouse hearts against diabetic cardiomyopathy, partially by suppressing NF-κB-dependent inflammatory responses and associated protein nitration. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Changes in catalase activity in leaves of woody and bushy plants in the conditions of air pollution by compounds of fluorine, sulfur and nitrogen

    Directory of Open Access Journals (Sweden)

    Y. Prysedskyj

    2016-08-01

    Full Text Available Recently environmental pollution by industrial waste products has become a significant environmental factor that essentially limits the vital functions of plants and reduces their species diversity. The antioxidant system is of special importance for tolerance reactions of plants to stressful environmental conditions, in particular, contamination by industrial pollutants. One of the constituents of this system is oxidoreductase, including catalase. Consequently, we have conducted experiments to determine how the nature of the complex compounds of fluorine, nitrogen and sulfur influences catalase activity in leaves of selected species of trees and shrubs. The investigation was made according to the complete factorial experiment that allowed us to study the effect of these pollutants both individually and in combination. We used the iodometric method to determine the level of catalase activity. Statistical analysis of the obtained results was performed by means of dispersion analysis with the comparison according to the Duncan method. The results of the research showed the possible impact of pollutants on the activity of catalase, which depends on the resilience of the plants, structure and duration of potency of the pollutants. With less resilient plant species (Sorbus aucuparia L., Fraxinus lanceolata Borkh. air pollution with a combination of fluorine, sulfur and nitrogen in most cases caused a reduction of catalase activity. Thus, in S. aucuparia a 5-hour exposure to low concentrations of pollutants (HF – 0.2 ml/m3, NH3 – 1.2 ml/m3, SO2 and H2SO4 – 0.9–1.0 ml/m3 caused an inhibition of catalase activity by 40.5%, and a ten-hour exposure caused a 61.4% inhibition compared with the control plants. With increased concentrations of pollutants  catalase function was inhibited by 35.8–73.6%, depending on the duration of their fumigation. For F. lanceolata, the pollutants’ effect on catalase activity caused a decrease in function of this

  3. Francisella tularensis Catalase Restricts Immune Function by Impairing TRPM2 Channel Activity.

    Science.gov (United States)

    Shakerley, Nicole L; Chandrasekaran, Akshaya; Trebak, Mohamed; Miller, Barbara A; Melendez, J Andrés

    2016-02-19

    As an innate defense mechanism, macrophages produce reactive oxygen species that weaken pathogens and serve as secondary messengers involved in immune function. The Gram-negative bacterium Francisella tularensis utilizes its antioxidant armature to limit the host immune response, but the mechanism behind this suppression is not defined. Here we establish that F. tularensis limits Ca(2+) entry in macrophages, thereby limiting actin reorganization and IL-6 production in a redox-dependent fashion. Wild type (live vaccine strain) or catalase-deficient F. tularensis (ΔkatG) show distinct profiles in their H2O2 scavenging rates, 1 and 0.015 pm/s, respectively. Murine alveolar macrophages infected with ΔkatG display abnormally high basal intracellular Ca(2+) concentration that did not increase further in response to H2O2. Additionally, ΔkatG-infected macrophages displayed limited Ca(2+) influx in response to ionomycin, as a result of ionophore H2O2 sensitivity. Exogenously added H2O2 or H2O2 generated by ΔkatG likely oxidizes ionomycin and alters its ability to transport Ca(2+). Basal increases in cytosolic Ca(2+) and insensitivity to H2O2-mediated Ca(2+) entry in ΔkatG-infected cells are reversed by the Ca(2+) channel inhibitors 2-aminoethyl diphenylborinate and SKF-96365. 2-Aminoethyl diphenylborinate but not SKF-96365 abrogated ΔkatG-dependent increases in macrophage actin remodeling and IL-6 secretion, suggesting a role for H2O2-mediated Ca(2+) entry through the transient receptor potential melastatin 2 (TRPM2) channel in macrophages. Indeed, increases in basal Ca(2+), actin polymerization, and IL-6 production are reversed in TRPM2-null macrophages infected with ΔkatG. Together, our findings provide compelling evidence that F. tularensis catalase restricts reactive oxygen species to temper macrophage TRPM2-mediated Ca(2+) signaling and limit host immune function. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  4. Comparative analysis of essential oil contents of Juniperus excelsa ...

    African Journals Online (AJOL)

    Cones/berries of Juniperus excelsa from three provenances in Balochistan, Pakistan were collected and essential oil was extracted by solvent method. Oil contents were analyzed on gas chromatography mass spectrometry (GCMS). Identification and quantification was made by using Wiley and NIST spectral library and HP ...

  5. Control of Phytolyma lata Walker (Scott.) Attack on Milicia excelsa ...

    African Journals Online (AJOL)

    species plot (protected by mesh netting: T1), mixed-species plot (Milicia + Terminalia), mixed-species plot with foliar chemical treatment (T3), mono-species with foliar chemical treatment (T4) and untreated mono-species plot of Milicia excelsa ...

  6. MAPK/JNK1 activation protects cells against cadmium-induced autophagic cell death via differential regulation of catalase and heme oxygenase-1 in oral cancer cells.

    Science.gov (United States)

    So, Keum-Young; Kim, Sang-Hun; Jung, Ki-Tae; Lee, Hyun-Young; Oh, Seon-Hee

    2017-10-01

    Antioxidant enzymes are related to oral diseases. We investigated the roles of heme oxygenase-1 (HO-1) and catalase in cadmium (Cd)-induced oxidative stress and the underlying molecular mechanism in oral cancer cells. Exposing YD8 cells to Cd reduced the expression levels of catalase and superoxide dismutase 1/2 and induced the expression of HO-1 as well as autophagy and apoptosis, which were reversed by N-acetyl-l-cysteine (NAC). Cd-exposed YD10B cells exhibited milder effects than YD8 cells, indicating that Cd sensitivity is associated with antioxidant enzymes and autophagy. Autophagy inhibition via pharmacologic and genetic modulations enhanced Cd-induced HO-1 expression, caspase-3 cleavage, and the production of reactive oxygen species (ROS). Ho-1 knockdown increased autophagy and apoptosis. Hemin treatment partially suppressed Cd-induced ROS production and apoptosis, but enhanced autophagy and CHOP expression, indicating that autophagy induction is associated with cellular stress. Catalase inhibition by pharmacological and genetic modulations increased Cd-induced ROS production, autophagy, and apoptosis, but suppressed HO-1, indicating that catalase is required for HO-1 induction. p38 inhibition upregulated Cd-induced phospho-JNK and catalase, but suppressed HO-1, autophagy, apoptosis. JNK suppression exhibited contrary results, enhancing the expression of phospho-p38. Co-suppression of p38 and JNK1 failed to upregulate catalase and procaspase-3, which were upregulated by JNK1 overexpression. Overall, the balance between the responses of p38 and JNK activation to Cd appears to have an important role in maintaining cellular homeostasis via the regulation of antioxidant enzymes and autophagy induction. In addition, the upregulation of catalase by JNK1 activation can play a critical role in cell protection against Cd-induced oxidative stress. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Humic acid effect on catalase activity and the generation of reactive oxygen species in corn (Zea mays).

    Science.gov (United States)

    Cordeiro, Flávio Couto; Santa-Catarina, Claudete; Silveira, Vanildo; de Souza, Sonia Regina

    2011-01-01

    Humic acids (HAs) have positive effects on plant physiology, but the molecular mechanisms underlying these events are only partially understood. The induction of root growth and emission of lateral roots (LRs) promoted by exogenous auxin is a natural phenomenon. Exogenous auxins are also associated with HA. Gas nitric oxide (NO) is a secondary messenger produced endogenously in plants. It is associated with metabolic events dependent on auxin. With the application of auxin, NO production is significantly increased, resulting in positive effects on plant physiology. Thus it is possible to evaluate the beneficial effects of the application of HA as an effect of auxin. To investigate the effects of HA the parameters of root growth, Zea mays was studied by evaluating the application of 3 mM C L⁻¹ of HA extracted from Oxisol and 100 µM SNP (sodium nitroprusside) and the NO donor, subject to two N-NO₃⁻, high dose (5.0 mM N-NO₃⁻) and low dose (5.0 mM N-NO₃⁻). Treatments with HA and NO were positively increased, regardless of the N-NO₃⁻ taken, as assessed by fresh weight and dry root, issue of LRs. The effects were more pronounced in the treatment with a lower dose of N-NO₃⁻. Detection of reactive oxygen species (ROS) in vivo and catalase activity were evaluated; these tests were associated with root growth. Under application of the bioactive substances tested, detection of ROS and catalase activity increased, especially in treatments with lower doses of N-NO₃⁻. The results of this experiment indicate that the effects of HA are dependent on ROS generation, which act as a messenger that induces root growth and the emission of LRs.

  8. Modulatory effect of pineapple peel extract on lipid peroxidation, catalase activity and hepatic biomarker levels in blood plasma of alcohol-induced oxidative stressed rats.

    Science.gov (United States)

    Okafor, O Y; Erukainure, O l; Ajiboye, J A; Adejobi, R O; Owolabi, F O; Kosoko, S B

    2011-01-01

    To investigate the ability of the methanolic extract of pineapple peel to modulate alcohol-induced lipid peroxidation, changes in catalase activities and hepatic biochemical marker levels in blood plasma. Oxidative stress was induced by oral administration of ethanol (20% w/v) at a dosage of 5 mL/kg bw in rats. After 28 days of treatment, the rats were fasted overnight and sacrificed by cervical dislocation. Blood was collected with a 2 mL syringe by cardiac puncture and was centrifuged at 3 000 rpm for 10 min. The plasma was analyzed to evaluate malondialdehyde (MDA), catalase activity, aspartate aminotransferase (AST), alkaline phosphatase (ALP) and alanine aminotransferase (ALT) concentrations. Administration of alcohol caused a drastic increase (87.74%) in MDA level compared with the control. Pineapple peel extract significantly reduced the MDA level by 60.16% at 2.5 mL/kg bw. Rats fed alcohol only had the highest catalase activity, treatment with pineapple peel extract at 2.5 mL/kg bw however, reduced the activity. Increased AST, ALP and ALT activities were observed in rats fed alcohol only respectively, treatment with pineapple peel extract drastically reduced their activities. The positive modulation of lipid peroxidation, catalase activities as well as hepatic biomarker levels of blood plasma by the methanolic extract of pineapple peels under alcohol-induced oxidative stress is an indication of its protective ability in the management of alcohol-induced toxicity.

  9. A natural xanthone increases catalase activity but decreases NF-kappa B and lipid peroxidation in U-937 and HepG2 cell lines.

    Science.gov (United States)

    Sahoo, Binay K; Zaidi, Adeel H; Gupta, Pankaj; Mokhamatam, Raveendra B; Raviprakash, Nune; Mahali, Sidhartha K; Manna, Sunil K

    2015-10-05

    Mangiferin, a C-glycosyl xanthone, has shown anti-inflammatory, antioxidant, and anti-tumorigenic activities. In the present study, we investigated the molecular mechanism for the antioxidant property of mangiferin. Considering the role of nuclear transcription factor kappa B (NF-κB) in inflammation and tumorigenesis, we hypothesized that modulating its activity will be a viable therapeutic target in regulating the redox-sensitive ailments. Our results show that mangiferin blocks several inducers, such as tumor necrosis factor (TNF), lypopolysaccharide (LPS), phorbol-12-myristate-13-acetate (PMA) or hydrogen peroxide (H2O2) mediated NF-κB activation via inhibition of reactive oxygen species generation. In silico docking studies predicted strong binding energy of mangiferin to the active site of catalase (-9.13 kcal/mol), but not with other oxidases such as myeloperoxidase, glutathione peroxidase, or inducible nitric oxide synthase. Mangiferin increased activity of catalase by 44%, but had no effect on myeloperoxidase activity in vitro. Fluorescence spectroscopy further revealed the binding of mangiferin to catalase at the single site with binding constant and binding affinity of 3.1×10(-7) M(-1) and 1.046 respectively. Mangiferin also inhibits TNF-induced lipid peroxidation and thereby protects apoptosis. Hence, mangiferin with its ability to inhibit NF-κB and increase the catalase activity may prove to be a potent therapeutic. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. In Vitro Assembly of Catalase*

    Science.gov (United States)

    Baureder, Michael; Barane, Elisabeth; Hederstedt, Lars

    2014-01-01

    Most aerobic organisms contain catalase, which functions to decompose hydrogen peroxide. Typical catalases are structurally complex homo-tetrameric enzymes with one heme prosthetic group buried in each subunit. It is not known how catalase in the cell is assembled from its constituents. The bacterium Enterococcus faecalis cannot synthesize heme but can acquire it from the environment to form a cytoplasmic catalase. We have in E. faecalis monitored production of the enzyme polypeptide (KatA) depending on the availability of heme and used our findings to devise a procedure for the purification of preparative amounts of in vivo-synthesized apocatalase. We show that fully active catalase can be obtained in vitro by incubating isolated apoprotein with hemin. We have characterized features of the assembly process and describe a temperature-trapped hemylated intermediate of the enzyme maturation process. Hemylation of apocatalase does not require auxiliary cell components, but rapid assembly of active enzyme seemingly is assisted in the cell. Our findings provide insight about catalase assembly and offer new experimental possibilities for detailed studies of this process. PMID:25148685

  11. In vitro assembly of catalase.

    Science.gov (United States)

    Baureder, Michael; Barane, Elisabeth; Hederstedt, Lars

    2014-10-10

    Most aerobic organisms contain catalase, which functions to decompose hydrogen peroxide. Typical catalases are structurally complex homo-tetrameric enzymes with one heme prosthetic group buried in each subunit. It is not known how catalase in the cell is assembled from its constituents. The bacterium Enterococcus faecalis cannot synthesize heme but can acquire it from the environment to form a cytoplasmic catalase. We have in E. faecalis monitored production of the enzyme polypeptide (KatA) depending on the availability of heme and used our findings to devise a procedure for the purification of preparative amounts of in vivo-synthesized apocatalase. We show that fully active catalase can be obtained in vitro by incubating isolated apoprotein with hemin. We have characterized features of the assembly process and describe a temperature-trapped hemylated intermediate of the enzyme maturation process. Hemylation of apocatalase does not require auxiliary cell components, but rapid assembly of active enzyme seemingly is assisted in the cell. Our findings provide insight about catalase assembly and offer new experimental possibilities for detailed studies of this process. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  12. CatB is Critical for Total Catalase Activity and Reduces Bactericidal Effects of Phenazine-1-Carboxylic Acid on Xanthomonas oryzae pv. oryzae and X. oryzae pv. oryzicola.

    Science.gov (United States)

    Pan, Xiayan; Wu, Jian; Xu, Shu; Duan, Yabing; Zhou, Mingguo

    2017-02-01

    Rice bacterial leaf blight, caused by Xanthomonas oryzae pv. oryzae, and rice bacterial leaf streak, caused by X. oryzae pv. oryzicola, are major diseases of rice. Phenazine-1-carboxylic acid (PCA) is a natural product that is isolated from Pseudomonas spp. and is used to control many important rice diseases in China. We previously reported that PCA disturbs the redox balance, which results in the accumulation of reactive oxygen species in X. oryzae pv. oryzae. In this study, we found that PCA significantly upregulated the transcript levels of catB and katE, which encode catalases, and that PCA sensitivity was reduced when X. oryzae pvs. oryzae and oryzicola were cultured with exogenous catalase. Furthermore, catB deletion mutants of X. oryzae pvs. oryzae and oryzicola showed dramatically decreased total catalase activity, increased sensitivity to PCA, and reduced virulence in rice. In contrast, deletion mutants of srpA and katG, which also encode catalases, exhibited little change in PCA sensitivity. The results indicate that catB in both X. oryzae pvs. oryzae and oryzicola encodes a catalase that helps protect the bacteria against PCA-induced stress.

  13. The Role of Catalase in Pulmonary Fibrosis

    Directory of Open Access Journals (Sweden)

    Takigawa Tomoko

    2010-12-01

    Full Text Available Abstract Background Catalase is preferentially expressed in bronchiolar and alveolar epithelial cells, and acts as an endogenous antioxidant enzyme in normal lungs. We thus postulated epithelial damage would be associated with a functional deficiency of catalase during the development of lung fibrosis. Methods The present study evaluates the expression of catalase mRNA and protein in human interstitial pneumonias and in mouse bleomycin-induced lung injury. We examined the degree of bleomycin-induced inflammation and fibrosis in the mice with lowered catalase activity. Results In humans, catalase was decreased at the levels of activity, protein content and mRNA expression in fibrotic lungs (n = 12 compared to control lungs (n = 10. Immunohistochemistry revealed a decrease in catalase in bronchiolar epithelium and abnormal re-epithelialization in fibrotic areas. In C57BL/6J mice, catalase activity was suppressed along with downregulation of catalase mRNA in whole lung homogenates after bleomycin administration. In acatalasemic mice, neutrophilic inflammation was prolonged until 14 days, and there was a higher degree of lung fibrosis in association with a higher level of transforming growth factor-β expression and total collagen content following bleomycin treatment compared to wild-type mice. Conclusions Taken together, these findings demonstrate diminished catalase expression and activity in human pulmonary fibrosis and suggest the protective role of catalase against bleomycin-induced inflammation and subsequent fibrosis.

  14. Engineering of a novel tri-functional enzyme with MnSOD, catalase and cell-permeable activities.

    Science.gov (United States)

    Luangwattananun, Piriya; Yainoy, Sakda; Eiamphungporn, Warawan; Songtawee, Napat; Bülow, Leif; Ayudhya, Chartchalerm Isarankura Na; Prachayasittikul, Virapong

    2016-04-01

    Cooperative function of superoxide dismutase (SOD) and catalase (CAT), in protection against oxidative stress, is known to be more effective than the action of either single enzyme. Chemical conjugation of the two enzymes resulted in molecules with higher antioxidant activity and therapeutic efficacy. However, chemical methods holds several drawbacks; e.g., loss of enzymatic activity, low homogeneity, time-consuming, and the need of chemical residues removal. Yet, the conjugated enzymes have never been proven to internalize into target cells. In this study, by employing genetic and protein engineering technologies, we reported designing and production of a bi-functional protein with SOD and CAT activities for the first time. To enable cellular internalization, cell penetrating peptide from HIV-1 Tat (TAT) was incorporated. Co-expression of CAT-MnSOD and MnSOD-TAT fusion genes allowed simultaneous self-assembly of the protein sequences into a large protein complex, which is expected to contained one tetrameric structure of CAT, four tetrameric structures of MnSOD and twelve units of TAT. The protein showed cellular internalization and superior protection against paraquat-induced cell death as compared to either complex bi-functional protein without TAT or to native enzymes fused with TAT. This study not only provided an alternative strategy to produce multifunctional protein complex, but also gained an insight into the development of therapeutic agent against oxidative stress-related conditions. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Catalase activity during C3-CAM transition in Mesembryanthemum crystallinum L. leaves.

    Science.gov (United States)

    Niewiadomska, E; Miszalski, Z; Slesak, I; Ratajczak, R

    1999-12-01

    Treatment with 0.4 mol dm(-3) NaCl caused a C3-CAM shift in Mesembryanthemum crystallinum L. leaves. In parallel to the CAM induction the activity of CAT was significantly decreased. In C3 and in CAM plants CAT activity showed daily fluctuations, with the maximum at the end of the light period. The oscillations of CAT were more pronounced in CAM than in C3 plants. In M. crystallinum CAT activity seems to respond more to CAM induction than to salinity.

  16. Effect of drought stress and subsequent recovery on protein, carbohydrate contents, catalase and peroxidase activities in three chickpea (Cicer arietinum) cultivars

    NARCIS (Netherlands)

    Mafakheri, A.; Siosemardeh, A.; Bahramnejad, B.; Struik, P.C.; Sohrabi, Y.

    2011-01-01

    Drought stress is one of the major abiotic stresses in agriculture worldwide. This study was carried out to investigate the effects of drought stress and subsequent recovery on protein, carbohydrate content, catalase (CAT), and peroxidase (POX) activities in three varieties of chickpea (drought

  17. Catalase activity as a biomarker for mild-stress-induced robustness in Bacillus weihenstephanensis

    NARCIS (Netherlands)

    Besten, den H.M.W.; Effraimidou, S.; Abee, T.

    2013-01-01

    Microorganisms are able to survive and grow in changing environments by activating stress adaptation mechanisms which may enhance bacterial robustness. Stress-induced enhanced robustness complicates the predictability of microbial inactivation. Using psychrotolerant Bacillus weihenstephanensis

  18. The effect of seedling chilling on glutathione content, catalase and peroxidase activity in Brassica oleracea L. var. italica

    Directory of Open Access Journals (Sweden)

    Renata Wojciechowska

    2013-09-01

    Full Text Available The study was designed to determine the possible relationship between Brassica oleracea var. italica seedlings stored at 2°C in the dark for seven and fourteen days, respectively, and the level of certain antioxidant parameters in particular organs. A parallel objective of the experiment was to determine if the reaction of seedlings to low temperature might be persistent in fully developed plants until harvest time. After 14 days of chilling a significant increase in the glutathione content was observed in the seedling leaves in comparison to the non-chilled plants. During vegetation in field conditions this effect was maintained in leaves up to the stage of formation of flower buds. At harvest the highest content of glutathione was demonstrated in broccoli heads, obtained from plants, which were previously chilled in the seedling phase for two weeks. Peroxidase activity in broccoli seedlings increased each year of the three-year study due to the duration of the cooling time, whereas in the case of catalase the changes were not so distinct. At harvest time the activity of both enzymes in the leaves and flower buds fluctuated according to the particular year of study.

  19. Activity of peroxisomal enzymes and intracellular distribution of catalase in Zellweger syndrome

    NARCIS (Netherlands)

    Schrakamp, G.; Bosch, H. van den; Roest, B.; Kos, M.; Meijer, A.J.; Heymans, H.S.A.; Tegelaers, W.H.H.; Schutgens, R.B.H.; Tager, J.M.; Wanders, R.J.A.

    1984-01-01

    The activity of peroxisomal enzymes was studied in human liver and cultured human skin fibroblasts in relation to the finding (Goldfischer, S. et al. (1973) Science 182, 62–64) that morphologically distinct peroxisomes are not detectable in patients with the cerebro-hepato-renal (Zellweger)

  20. Cytochemical Localization of Catalase Activity in Methanol-Grown Hansenula polymorpha

    NARCIS (Netherlands)

    Dijken, J.P. van; Veenhuis, M.; Vermeulen, C.A.; Harder, W.

    1975-01-01

    The localization of peroxidase activity in methanol-grown cells of the yeast Hansenula polymorpha has been studied by a method based on cytochemical staining with diaminobenzidine (DAB). The oxidation product of DAB occurred in microbodies, which characteristically develop during growth on methanol,

  1. Activity of peroxisomal enzymes and intracellular distribution of catalase in Zellweger syndrome

    NARCIS (Netherlands)

    Wanders, R. J.; Kos, M.; Roest, B.; Meijer, A. J.; Schrakamp, G.; Heymans, H. S.; Tegelaers, W. H.; van den Bosch, H.; Schutgens, R. B.; Tager, J. M.

    1984-01-01

    The activity of peroxisomal enzymes was studied in human liver and cultured human skin fibroblasts in relation to the finding (Goldfischer, S. et al. (1973) Science 182, 62-64) that morphologically distinct peroxisomes are not detectable in patients with the cerebro-hepato-renal (Zellweger)

  2. Thermus thermophilus as a cell factory for the production of a thermophilic Mn-dependent catalase which fails to be synthesized in an active form in Escherichia coli.

    Science.gov (United States)

    Hidalgo, Aurelio; Betancor, Lorena; Moreno, Renata; Zafra, Olga; Cava, Felipe; Fernández-Lafuente, Roberto; Guisán, José M; Berenguer, José

    2004-07-01

    Thermostable Mn-dependent catalases are promising enzymes in biotechnological applications as H(2)O(2)-detoxifying systems. We cloned the genes encoding Mn-dependent catalases from Thermus thermophilus HB27 and HB8 and a less thermostable mutant carrying two amino acid replacements (M129V and E293G). When the wild-type and mutant genes were overexpressed in Escherichia coli, unmodified or six-His-tagged proteins of the expected size were overproduced as inactive proteins. Several attempts to obtain active forms or to activate the overproduced proteins were unsuccessful, even when soluble and thermostable proteins were used. Therefore, a requirement for a Thermus-specific activation factor was suggested. To overcome this problem, the Mn-dependent catalase genes were overexpressed directly in T. thermophilus under the control of the Pnar promoter. This promoter belongs to a respiratory nitrate reductase from of T. thermophilus HB8, whose transcription is activated by the combined action of nitrate and anoxia. Upon induction in T. thermophilus HB8, a 20- to 30-fold increase in catalase specific activity was observed, whereas a 90- to 110-fold increase was detected when the laboratory strain T. thermophilus HB27::nar was used as the host. The thermostability of the overproduced wild-type catalase was identical to that previously reported for the native enzyme, whereas decreased stability was detected for the mutant derivative. Therefore, our results validate the use of T. thermophilus as an alternative cell factory for the overproduction of thermophilic proteins that fail to be expressed in well-known mesophilic hosts.

  3. Ascorbate Peroxidase and Catalase Activities and Their Genetic Regulation in Plants Subjected to Drought and Salinity Stresses.

    Science.gov (United States)

    Sofo, Adriano; Scopa, Antonio; Nuzzaci, Maria; Vitti, Antonella

    2015-06-12

    Hydrogen peroxide (H2O2), an important relatively stable non-radical reactive oxygen species (ROS) is produced by normal aerobic metabolism in plants. At low concentrations, H2O2 acts as a signal molecule involved in the regulation of specific biological/physiological processes (photosynthetic functions, cell cycle, growth and development, plant responses to biotic and abiotic stresses). Oxidative stress and eventual cell death in plants can be caused by excess H2O2 accumulation. Since stress factors provoke enhanced production of H2O2 in plants, severe damage to biomolecules can be possible due to elevated and non-metabolized cellular H2O2. Plants are endowed with H2O2-metabolizing enzymes such as catalases (CAT), ascorbate peroxidases (APX), some peroxiredoxins, glutathione/thioredoxin peroxidases, and glutathione sulfo-transferases. However, the most notably distinguished enzymes are CAT and APX since the former mainly occurs in peroxisomes and does not require a reductant for catalyzing a dismutation reaction. In particular, APX has a higher affinity for H2O2 and reduces it to H2O in chloroplasts, cytosol, mitochondria and peroxisomes, as well as in the apoplastic space, utilizing ascorbate as specific electron donor. Based on recent reports, this review highlights the role of H2O2 in plants experiencing water deficit and salinity and synthesizes major outcomes of studies on CAT and APX activity and genetic regulation in drought- and salt-stressed plants.

  4. Ascorbate Peroxidase and Catalase Activities and Their Genetic Regulation in Plants Subjected to Drought and Salinity Stresses

    Directory of Open Access Journals (Sweden)

    Adriano Sofo

    2015-06-01

    Full Text Available Hydrogen peroxide (H2O2, an important relatively stable non-radical reactive oxygen species (ROS is produced by normal aerobic metabolism in plants. At low concentrations, H2O2 acts as a signal molecule involved in the regulation of specific biological/physiological processes (photosynthetic functions, cell cycle, growth and development, plant responses to biotic and abiotic stresses. Oxidative stress and eventual cell death in plants can be caused by excess H2O2 accumulation. Since stress factors provoke enhanced production of H2O2 in plants, severe damage to biomolecules can be possible due to elevated and non-metabolized cellular H2O2. Plants are endowed with H2O2-metabolizing enzymes such as catalases (CAT, ascorbate peroxidases (APX, some peroxiredoxins, glutathione/thioredoxin peroxidases, and glutathione sulfo-transferases. However, the most notably distinguished enzymes are CAT and APX since the former mainly occurs in peroxisomes and does not require a reductant for catalyzing a dismutation reaction. In particular, APX has a higher affinity for H2O2 and reduces it to H2O in chloroplasts, cytosol, mitochondria and peroxisomes, as well as in the apoplastic space, utilizing ascorbate as specific electron donor. Based on recent reports, this review highlights the role of H2O2 in plants experiencing water deficit and salinity and synthesizes major outcomes of studies on CAT and APX activity and genetic regulation in drought- and salt-stressed plants.

  5. Bentonite-supported catalase

    Directory of Open Access Journals (Sweden)

    H. CEYLAN

    2005-05-01

    Full Text Available The properties of the clay bentonite as a support for enzyme immobilization were studied using the enzyme catalase. Such an immobilization does not result in enzyme inactivation and constitutes a valuable method for immobilizing catalase at high ionic strength. The bentonite-supported catalase was characterized in terms of pH and ionic strength dependencies, thermal and storage stability and kinetic parameters. These studies indicate that bentonite is a valuable support for the simple adsorption of enzymes.

  6. Nitroxides protect horseradish peroxidase from H2O2-induced inactivation and modulate its catalase-like activity.

    Science.gov (United States)

    Samuni, Amram; Maimon, Eric; Goldstein, Sara

    2017-08-01

    Horseradish peroxidase (HRP) catalyzes H2O2 dismutation while undergoing heme inactivation. The mechanism underlying this process has not been fully elucidated. The effects of nitroxides, which protect metmyoglobin and methemoglobin against H2O2-induced inactivation, have been investigated. HRP reaction with H2O2 was studied by following H2O2 depletion, O2 evolution and heme spectral changes. Nitroxide concentration was followed by EPR spectroscopy, and its reactions with the oxidized heme species were studied using stopped-flow. Nitroxide protects HRP against H2O2-induced inactivation. The rate of H2O2 dismutation in the presence of nitroxide obeys zero-order kinetics and increases as [nitroxide] increases. Nitroxide acts catalytically since its oxidized form is readily reduced to the nitroxide mainly by H2O2. The nitroxide efficacy follows the order 2,2,6,6-tetramethyl-piperidine-N-oxyl (TPO)>4-OH-TPO>3-carbamoyl proxyl>4-oxo-TPO, which correlates with the order of the rate constants of nitroxide reactions with compounds I, II, and III. Nitroxide catalytically protects HRP against inactivation induced by H2O2 while modulating its catalase-like activity. The protective role of nitroxide at μM concentrations is attributed to its efficient oxidation by P940, which is the precursor of the inactivated form P670. Modeling the dismutation kinetics in the presence of nitroxide adequately fits the experimental data. In the absence of nitroxide the simulation fits the observed kinetics only if it does not include the formation of a Michaelis-Menten complex. Nitroxides catalytically protect heme proteins against inactivation induced by H2O2 revealing an additional role played by nitroxide antioxidants in vivo. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Correlation between acid, TBA, peroxide and iodine values, catalase and glutathione peroxidase activities of chicken, cattle and camel meat during refrigerated storage

    Directory of Open Access Journals (Sweden)

    Hamid Reza Gheisari

    2011-08-01

    Full Text Available The aim of this study was correlation determination between fat putrefaction indices and antioxidative enzymes in chicken, cattle and camel meat during refrigerated storage. Longissimus dorsi muscle of three Iranian dromedary one humped camel and three Holstein cattle and breast muscle of three broiler breeder chicken were obtained from the carcasses 3 days postmortem. The samples were ground and stored at 4 °C for 0, 2, or 4 days. Peroxide, TBA, acid and iodine values, catalase and glutathione peroxidase (GSH-Px activities of the muscles were performed in each storage time. Catalase and GSH-Px activities were much higher in camel than in chicken and cattle and higher in cattle than in chicken. TBA value was lower in chicken than in camel. Camel had higher acid value than cattle. Chicken showed the highest and camel had the lowest iodine values. Catalase and GSH-Px activities and iodine values were quite stable during refrigerated storage. Acid values increased significantly over storage days in cattle. During the 4-day storage period, TBA and peroxide values increased. GSH-Px activity showed negative correlation with acid and TBA values in chicken and cattle. Acid value (for chicken and cattle and peroxide value (for 3 animal species showed positive correlation with TBA content. Iodine value had positive correlation with catalase activity in cattle and negative correlation with peroxide and TBA values in camel. In conclusion, our results indicate that peroxide and TBA values can be used as lipid quality indices in chicken, cattle and camel meat during 4 day storage in refrigerator. [Vet. World 2011; 4(4.000: 153-157

  8. A high constitutive catalase activity confers resistance to methyl viologen-promoted oxidative stress in a mutant of the cyanobacterium Nostoc punctiforme ATCC 29133.

    Science.gov (United States)

    Moirangthem, Lakshmipyari Devi; Bhattacharya, Sudeshna; Stensjö, Karin; Lindblad, Peter; Bhattacharya, Jyotirmoy

    2014-04-01

    A spontaneous methyl viologen (MV)-resistant mutant of the nitrogen-fixing cyanobacterium Nostoc punctiforme ATCC 29133 was isolated and the major enzymatic antioxidants involved in combating MV-induced oxidative stress were evaluated. The mutant displayed a high constitutive catalase activity as a consequence of which, the intracellular level of reactive oxygen species in the mutant was lower than the wild type (N. punctiforme) in the presence of MV. The superoxide dismutase (SOD) activity that consisted of a SodA (manganese-SOD) and a SodB (iron-SOD) was not suppressed in the mutant following MV treatment. The mutant was, however, characterised by a lower peroxidase activity compared with its wild type, and its improved tolerance to externally added H₂O₂ could only be attributed to enhanced catalase activity. Furthermore, MV-induced toxic effects on the wild type such as (1) loss of photosynthetic performance assessed as maximal quantum yield of photosystem II, (2) nitrogenase inactivation, and (3) filament fragmentation and cell lysis were not observed in the mutant. These findings highlight the importance of catalase in preventing MV-promoted oxidative damage and cell death in the cyanobacterium N. punctiforme. Such oxidative stress resistant mutants of cyanobacteria are likely to be a better source of biofertilisers, as they can grow and fix nitrogen in an unhindered manner in agricultural fields that are often contaminated with the herbicide MV, also commonly known as paraquat.

  9. Optimization of extracellular catalase production from Aspergillus ...

    African Journals Online (AJOL)

    aghomotsegin

    somes but not usually excreted from the cell. Industrially, the extracellular .... aConcentration (g/L) ; bConcentration (mg/L); CDW, cell dry weight ; E.A, extracellular catalase activity ; LL, low level; HL, high level. was used for the ..... and their relationship to other eukaryotic and prokaryotic catalases. J. Mol. Evol. 42(5): ...

  10. Changing of Bacteria Catalase Activity Under the Influence of Electro-Magnetic Radiation on a Frequency of Nitric Oxide Absorption and Radiation Molecular Spectrum

    Directory of Open Access Journals (Sweden)

    G.M. Shub

    2009-09-01

    Full Text Available The dynamics of catalase activity degree changing in Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa is described under the influence of electro-magnetic radiation on a frequency of nitric oxide absorption and radiation molecular spectrum. The panoramic spectrometric measuring complex, developed in Central Scientific Research Institute of measuring equipment Public corporation, Saratov, was used while carrying out the research. Electromagnetic vibrations of extremely high frequencies were stimulated in this complex imitating the structure of nitric oxide absorption and radiation molecular spectrum. The growth of activity of the mentioned enzyme of the strains under research was detected. The most significant changes were observed under 60-minutes exposure.

  11. Ethnobotanical review and pharmacological properties of selected medicinal plants in Brunei Darussalam: Litsea elliptica, Dillenia suffruticosa, Dillenia excelsa, Aidia racemosa, Vitex pinnata and Senna alata

    OpenAIRE

    May Poh Yik Goh; Aida Maryam Basri; Hartini Yasin; Hussein Taha; Norhayati Ahmad

    2017-01-01

    The aim of the current study is to review the medicinal properties of the plants found in Brunei Darussalam namely Litsea elliptica, Dillenia suffruticosa, Dillenia excelsa, Aidia racemosa, Vitex pinnata and Senna alata. The known phytochemical constituents of these plants and their ability to bring about a range of biological activities are included in this review. These plants have been used traditionally for a multitude of diseases and illnesses. There is a lot of untapped potential in the...

  12. Aproveitamento do café Excelsa em mistura com o café Árábica Use of Excelsa coffee in blends with Arabica

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    Alcides Carvalho

    1990-01-01

    Full Text Available O café Excelsa (Coffea dewevrei cv. Excelsa, embora rústico e produtivo, não é comercialmente cultivado. No presente trabalho, procurou-se avaliar a qualidade de sua bebida em mistura, em diferentes proporções, com o café Arábica (C. arabica de bebida boa. Usou-se delineamento em blocos incompletos balanceados, com oito tratamentos e sete repetições, além de um controle adicional de Arábica de bebida mole, e adotou-se a escala de 0 a 5 pontos, normalmente usada na classificação da bebida do Arábica. Durante a torração, o Excelsa apresentou aroma desagradável; a infusão, logo que colocada na xícara, também mostrou aroma estranho, o qual desapareceu algum tempo depois. As amostras do Arábica deram bebida mole, com média de 3,76 pontos, e, as de Excelsa, bebida inferior, com média de 1,64 ponto apenas. As médias de pontos conferidas à bebida das misturas de 10,20,30,40 e 50% de Excelsa com Arábica foram de 3,23, 2,95, 2,91, 2,67 e 1,91 respectivamente. Os provadores detectaram gosto estranho em 85,71 % das amostras do Excelsa. Nas misturas, esse gosto foi observado em escala crescente com a adição do café Excelsa. Encontrou-se uma correlação positiva e significativa (r =0,91 entre a quantidade do Excelsa na mistura e a porcentagem de amostras com gosto estranho. Houve variação entre os provadores com relação à sensibilidade para esse gosto. Correlação negativa e significativa (r =-0,93 foi notada entre a quantidade do Excelsa na mistura e a qualidade da bebida. Os resultados gerais indicam a possibilidade de se adicionar até 23% desse café em mistura com o Arábica de bebida boa, sem, contudo, provocar grandes alterações na qualidade da bebida.Among the known coffee species only Coflea arabica (Arabica coffee and C. canephora (Robusta coffee have economic importance in international market Excelsa coffee (C.dewevrei cv.Excelsa in spite of its rusticity, high yielding capacity and normal sized grains is not

  13. Age-related changes in catalase, glutathione reductase activities, the amount of glutathione in total body of oregon and vestigial Drosophila melanogaster.

    Science.gov (United States)

    Fiskin, K; Kandemir, S; Hamamci, D; Yesilada, E; Bozcuk, A N

    1994-01-01

    Natural antioxidants, free radical scavengers as catalase, glutathione reductase and glutathione are considered for aging mechanism. The objective of our study was to investigate the differences in the life span of male Oregon (w.t.) and vestigial Drosophila melanogaster, the possible role of free radical scavengers such as catalase, glutathione reductase and reduced-oxidized glutathione levels in the aging process by studying the pattern of age-related changes. The life span of male Oregon D. melanogaster is longer than that of the vestigial D. melanogaster. The beginning of the dying phase of Oregon was around 40 days, while the vestigial's around 20 days. The maximum life span was 85 days in Oregon population and 56 days in vestigial population. Age-related changes of catalase activities were similar in male Oregon and vestigial and showed a decreasing curve during aging. Glutathione reductase activity of Oregon increased slightly between 10 and 40 days, decreased sharply therafter. Glutathione reductase activity of vestigial followed a pot-shaped trend with 60% decrease during the first 40 days and followed by a sharp increase during the late part of life. The amounts of reduced glutathione (GSH) and oxidized glutathione (GSSG) increased slightly up to 40 days of age and followed a sharp decline thereafter in male Oregon D. melanogaster. In male vestigial D. melanogaster, the concentrations of GSH and GSSG remained quite stable for the nogaster, the concentrations of GSH and GSSG remained quite stable for the first 10 days, followed by a sharp decline around 20th day and increased thereafter.

  14. COMPARED ANALYSIS OF CATALASE AND PEROXIDASE ACTIVITY IN CELLULOLYTIC FUNGUS TRICHODERMA REESEI GROWN ON MEDIUM WITH DIFFERENT CONCENTRATIONS OF GRINDED WHEAT AND BARLEY STRAWS

    Directory of Open Access Journals (Sweden)

    Mihaela Cristica

    2010-09-01

    Full Text Available The purpose of this study was to assess the evolution of catalase and peroxidase activity in Trichoderma reesei grown on medium containing grinded wheat and barley straws. Carbon source of cultivation medium - glucose was replaced by various concentrations of grinded wheat and barley straws, finally resulting three experimental variants as follows: V1 = 20 g/l, V2 = 30 g/l, V3 = 40 g/l. ĂŽn addition to these variants a control sample was added in which composition remainded unchanged. The catalase activity was determined by spectrophotometric Sinha method (Artenie et al., 2008 while peroxidase activity was assesed using the o-dianisidine method (Cojocaru, 2009. Enzymatic determinations were carried out at 7 and 14 days from inoculation, in both fungus mycelium and culture liquid. The enzymatic assay showed significant differences between determinations intervals and work variants. Enzyme activity is influenced by the age of fungus and by the different nature of the substrate used.

  15. THE ANALYSIS OF CATALASE AND PEROOXIDASE ACTIVITY IN SAPROPHYTIC FUNGUS RHIZOPUS NIGRICANS GROWN ON MEDIUM WHITH DIFERENT CONCENTRATION OF GRINDED CORN CARYOPSIS

    Directory of Open Access Journals (Sweden)

    Tamara Barbaneagra

    2010-09-01

    Full Text Available The purpose of this study was to assay catalase and peroxidase activity in the saprophytic fungus Rhizopus nigricans, grown on mediums containing grinded corn caryopsis, which, in our experiments have replaced carbon source – sucrose in composition of liquid culture medium Czapeck Dox, resulting in the final three experimental variants: V1 = 20 g/l, V2 = 30 g/l, V3 = 40 g/l, while the control variant composition remained unchanged. Measurements were made at three time intervals: 5 days and 10 days and 15 days after inoculation, using fungus mycelium and culture liquid. Determination of catalase activity was performed using Sinha method (Artenie Vl., et al., 2008, and determination of peroxidase was carried out on the basis of ortho-dianisidine method (Cojocaru D.C., 2009. The results showed significant deferens in dynamic of enzyme activity depending on the concentration of carbon source introduced into the medium and age of the fungus.

  16. Lead-induced stress, which triggers the production of nitric oxide (NO) and superoxide anion (O2·-) in Arabidopsis peroxisomes, affects catalase activity.

    Science.gov (United States)

    Corpas, Francisco J; Barroso, Juan B

    2017-08-01

    Lead (Pb) contamination has a toxic effect on plant metabolisms, leading to a decrease in biomass production. The free radical nitric oxide (NO) is involved in the mechanism of response to a wide range of abiotic stresses. However, little is known about the interplay between Pb-induced stress and NO metabolism. Peroxisomes are sub-cellular compartments involved in multiple cellular metabolic pathways which are characterized by an active nitro-oxidative metabolism. Thus, Arabidopsis thaliana mutants expressing cyan fluorescent protein (CFP) through the addition of peroxisomal targeting signal 1 (PTS1), which enables peroxisomes to be visualized in vivo by confocal laser scanning microscopy (CLSM) combined with fluorescent probes for nitric oxide (NO), superoxide anion (O2·-) and peroxynitrite (ONOO-), were used to evaluate the potential involvement of these organelles in the mechanism of response to 150 μM lead-induced stress. Both NO and O2·- radicals, and consequently ONOO-, were overproduced under Pb-stress. Additionally, biochemical and gene expression analyses of peroxisomal enzymes, including the antioxidant catalase (CAT) and two photorespiration enzymes, such as glycolate oxidase (GOX) and hydroxypyruvate reductase (HPR), show that, under Pb-stress, only the catalase was negatively affected, while the two photorespiration enzymes remained unaffected. These results corroborate the involvement of plant peroxisomal metabolisms in the mechanism of response to lead contamination and highlight the importance of the peroxisomal NO metabolism. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Expression of tobacco class II catalase gene activates the endogenous homologous gene and is associated with disease resistance in transgenic potato plants.

    Science.gov (United States)

    Yu, D; Xie, Z; Chen, C; Fan, B; Chen, Z

    1999-02-01

    We have previously shown that healthy potato plants respond poorly to salicylic acid (SA) for activating disease resistance against the late blight fungal pathogen Phytophthora infestans. However, SA is essential for the establishment of potato systemic acquired resistance (SAR) against P. infestans after treatment with the fungal elicitor arachidonic acid (AA). To understand the molecular mechanisms through which AA induces SA-dependent SAR in potato, we have recently studied the expression of potato class II catalase (Cat2St) in comparison with its tobacco homologue, Cat2Nt, which has previously been shown to bind SA. In the present study, we show that tobacco Cat2Nt is expressed at high levels and accounts for almost half of total SA-binding activity detected in tobacco leaves. In contrast, potato Cat2St is not expressed in healthy leaves, which is associated with the low SA responsiveness of potato plants for activation of disease resistance mechanisms. Upon treatment with AA, expression of potato Cat2St is induced not only in AA-treated leaves, but also in the upper untreated parts of the plants, concomitant with the establishment of SA-dependent SAR to P. infestans. Moreover, expression of the tobacco Cat2Nt gene in transgenic potato plants leads to constitutive expression of the endogenous potato Cat2St gene and is associated with enhanced resistance to P. infestans. These results collectively indicate that plant SA-binding class II catalases may play an important role in the development of disease resistance, possibly by serving as biological targets of SA.

  18. Effect of Yerbimat herbicide on lipid peroxidation, catalase activity, and histological damage in gills and liver of the freshwater fish Goodea atripinnis.

    Science.gov (United States)

    Ortiz-Ordoñez, Esperanza; Uría-Galicia, Esther; Ruiz-Picos, Ricardo Arturo; Duran, Angela Georgina Sánchez; Trejo, Yoseline Hernández; Sedeño-Díaz, Jacinto Elías; López-López, Eugenia

    2011-10-01

    The use of herbicides for agricultural and aquatic weed control has increased worldwide. These substances are potentially toxic pollutants because they induce the production of reactive oxygen species for biological systems and exert oxidative stress in nontarget organisms living in the treated aquatic systems. Recent evidence suggests differences in the toxicity of glyphosate in the form of an active ingredient compared to the toxicity of glyphosate in combination with surfactants, such as those found in commercial formulations. In Mexico, one of the most widely used glyphosate-based herbicides is Yerbimat, which has agricultural as well as aquatic weed control applications. However, there are no aquatic toxicity data, particularly regarding native fish. Therefore, we determined the acute toxicity of commercial-formulation Yerbimat in a static bioassay at 96 h (LC(50)). We also determined its toxicity at 96 h in sublethal concentrations to assess the lipid peroxidation levels (LPX), catalase activity, hepatic glycogen content, and histological damage in the liver and gills of the fish Goodea atripinnis associated with chronic exposure (75 days). The LC(50) was 38.95 ± 0.33 mg/L. The results of the short-term exposure study indicate that Yerbimat can potentially induce oxidative stress in G. atripinnis, because LPX was increased in the gills and liver. Catalase activity was reduced in the gills but increased in the liver, whereas hepatic glycogen was depleted. Chronic exposure was associated with histopathological damage in the gills and liver, some of which was irreversible. Yerbimat represents a potential risk for aquatic biota; therefore, we recommend that its application be carefully considered. © Springer Science+Business Media, LLC 2011

  19. Caribbean yellow band disease compromises the activity of catalase and glutathione S-transferase in the reef-building coral Orbicella faveolata exposed to anthracene.

    Science.gov (United States)

    Montilla, Luis Miguel; Ramos, Ruth; García, Elia; Cróquer, Aldo

    2016-05-03

    Healthy and diseased corals are threatened by different anthropogenic sources, such as pollution, a problem expected to become more severe in the near future. Despite the fact that coastal pollution and coral diseases might represent a serious threat to coral reef health, there is a paucity of controlled experiments showing whether the response of diseased and healthy corals to xenobiotics differs. In this study, we exposed healthy and Caribbean yellow band disease (CYBD)-affected Orbicella faveolata colonies to 3 sublethal concentrations of anthracene to test if enzymatic responses to this hydrocarbon were compromised in CYBD-affected tissues. For this, a 2-factorial fully orthogonal design was used in a controlled laboratory bioassay, using tissue condition (2 levels: apparently healthy and diseased) and pollutant concentration (4 levels: experimental control, 10, 30 and 100 ppb concentration) as fixed factors. A permutation-based ANOVA (PERMANOVA) was used to test the effects of condition and concentration on the specific activity of 3 enzymatic biomarkers: catalase, glutathione S-transferase, and glutathione peroxidase. We found a significant interaction between the concentration of anthracene and the colony condition for catalase (Pseudo-F = 3.84, df = 3, p < 0.05) and glutathione S-transferase (Pseudo-F = 3.29, df = 3, p < 0.05). Moreover, our results indicated that the enzymatic response to anthracene in CYBD-affected tissues was compromised, as the activity of these enzymes decreased 3- to 4-fold compared to healthy tissues. These results suggest that under a potential scenario of increasing hydrocarbon coastal pollution, colonies of O. faveolata affected with CYBD might become more vulnerable to the deleterious effects of chemical pollution.

  20. Nickel in Soil Modifies Sensitivity to Diazinon Measured by the Activity of Acetylcholinesterase, Catalase, and Glutathione S-Transferase in Earthworm Eisenia fetida

    Directory of Open Access Journals (Sweden)

    Agnieszka Zawisza-Raszka

    2013-01-01

    Full Text Available Nickel in typical soils is present in a very low concentration, but in the contaminated soils it occurs in locally elevated concentrations. The aim of this study was to examine the effect of nickel in the concentrations of 300 (very high, close to LOEC for reproduction and 900 (extremely high, close to LOEC for mortality mg/kg dry soil on the life history and acetylcholinesterase, catalase, and glutathione S-transferase activities in earthworm Eisenia fetida and to establish how nickel modifies the sensitivity to organophosphorous pesticide—diazinon. Cocoons production and juveniles’ number were significantly lower only in groups exposed to Ni in the concentration of 900 mg/kg dry soil for two months. Diazinon administration diminished the AChE activity in the GI tract and in the body wall. The interaction between diazinon and nickel was observed, and, in consequence, the AChE activity after the pesticide treatment was similar to controls in worms preexposed to nickel. Both pesticide administration and exposure to nickel caused an increase in the GST activity in examined organs and CAT activity in body wall. Both biometric and development data and simple enzymatic analysis, especially the AChE and GST, show a Ni pretreatment effect on the subsequent susceptibility to pesticide.

  1. Peroxidase and catalase activities are involved in direct adventitious shoot formation induced by thidiazuron in eastern white pine (Pinus strobus L.) zygotic embryos.

    Science.gov (United States)

    Tang, Wei; Newton, Ronald J

    2005-08-01

    We reported establishment of an efficient plant regeneration procedure through direct adventitious shoot (DAS) formation from cotyledons and hypocotyls of eastern white pine (Pinus strobus L.) mature embryos in this investigation. Multiple DASs were initiated from cotyledons of embryos on PS medium containing N6-benzyladenine (BA), thidiazuron (TDZ), or kinetin (KIN). Among different concentrations of casein enzymatic hydrosylate (CH) and glutamine used in this study, 500 mg l(-1) CH or 600 mg l(-1) glutamine induced the highest frequency of DAS formation. Rooting of regenerated shoots was obtained on PS medium supplemented with 0.01-0.1 microM indole-3-acetic acid (IAA) with the highest frequency on medium containing 0.01 muM IAA. No DASs were obtained on medium without TDZ. Measurement of peroxidase (POD) and catalase (CAT) activity during direct shoot induction and differentiation demonstrated that the lowest POD activity appeared in the 5-6th week of culture and lowest CAT activity occurred in the 7-8th week of culture on medium with TDZ. No such a change in POD and CAT activities was observed on medium without TDZ. These results demonstrated that POD and CAT activities were involved in DAS formation induced by TDZ in eastern white pine.

  2. Molecular Characterization of a Catalase from Hydra vulgaris

    Science.gov (United States)

    Dash, Bhagirathi; Phillips, Timothy D.

    2012-01-01

    Catalase, an antioxidant and hydroperoxidase enzyme protects the cellular environment from harmful effects of hydrogen peroxide by facilitating its degradation to oxygen and water. Molecular information on a cnidarian catalase and/or peroxidase is, however, limited. In this work an apparent full length cDNA sequence coding for a catalase (HvCatalase) was isolated from Hydra vulgaris using 3’- and 5’- (RLM) RACE approaches. The 1859 bp HvCatalase cDNA included an open reading frame of 1518 bp encoding a putative protein of 505 amino acids with a predicted molecular mass of 57.44 kDa. The deduced amino acid sequence of HvCatalase contained several highly conserved motifs including the heme-ligand signature sequence RLFSYGDTH and the active site signature FXRERIPERVVHAKGXGA. A comparative analysis showed the presence of conserved catalytic amino acids [His(71), Asn(145), and Tyr(354)] in HvCatalase as well. Homology modeling indicated the presence of the conserved features of mammalian catalase fold. Hydrae exposed to thermal, starvation, metal and oxidative stress responded by regulating its catalase mRNA transcription. These results indicated that the HvCatalase gene is involved in the cellular stress response and (anti)oxidative processes triggered by stressor and contaminant exposure. PMID:22521743

  3. Metallic mercury uptake by catalase Part 1 In Vitro metallic mercury uptake by various kind of animals' erythrocytes and purified human erythrocyte catalase

    OpenAIRE

    劒持,堅志

    1980-01-01

    The uptake of metallic mercury was studied using erythrocytes with different catalase activities taken from various kind of animals. The results were: 1) The uptake of metallic mercury by erythrocytes paralleled the activity of catalase in the erythrocytes with and without hydrogen peroxide, suggesting that the erythrocyte catalase activity is related to the uptake of metallic mercury. 2) The uptake of metallic mercury occurred not only with purified human erythrocyte catalase but also with h...

  4. Modulation of the activities of catalase, cu-zn, mn superoxide dismutase, and glutathione peroxidase in adipocyte from ovariectomised female rats with metabolic syndrome.

    Science.gov (United States)

    Guerra, Rebeca Cambray; Zuñiga-Muñoz, Alejandra; Guarner Lans, Verónica; Díaz-Díaz, Eulises; Tena Betancourt, Carlos Alberto; Pérez-Torres, Israel

    2014-01-01

    The aim of this study was to evaluate the association between estrogen removal, antioxidant enzymes, and oxidative stress generated by obesity in a MS female rat model. Thirty two female Wistar rats were divided into 4 groups: Control (C), MS, MS ovariectomized (Ovx), and MS Ovx plus estradiol (E2). MS was induced by administering 30% sucrose to drinking water for 24 weeks. After sacrifice, intra-abdominal fat was dissected; adipocytes were isolated and lipid peroxidation, non-enzymatic antioxidant capacity, and the activities of Cu-Zn and Mn superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) were determined. There were no significant differences in the activities of Cu-Zn, Mn SOD, CAT, and GPx between the C and MS groups, but in the MS Ovx group there was a statistically significant decrease in the activities of these enzymes when compared to MS and MS Ovx+E2. The increased lipid peroxidation and nonenzymatic antioxidant capacity found in MS Ovx was significantly decreased when compared to MS and MS Ovx+E2. In conclusion, the removal of E2 by ovariectomy decreases the activity of the antioxidant enzymes in the intra-abdominal tissue of MS female rats; this is reflected by increased lipid peroxidation and decreased nonenzymatic antioxidant capacity.

  5. Modulation of the Activities of Catalase, Cu-Zn, Mn Superoxide Dismutase, and Glutathione Peroxidase in Adipocyte from Ovariectomised Female Rats with Metabolic Syndrome

    Directory of Open Access Journals (Sweden)

    Rebeca Cambray Guerra

    2014-01-01

    Full Text Available The aim of this study was to evaluate the association between estrogen removal, antioxidant enzymes, and oxidative stress generated by obesity in a MS female rat model. Thirty two female Wistar rats were divided into 4 groups: Control (C, MS, MS ovariectomized (Ovx, and MS Ovx plus estradiol (E2. MS was induced by administering 30% sucrose to drinking water for 24 weeks. After sacrifice, intra-abdominal fat was dissected; adipocytes were isolated and lipid peroxidation, non-enzymatic antioxidant capacity, and the activities of Cu-Zn and Mn superoxide dismutase (SOD, catalase (CAT, and glutathione peroxidase (GPx were determined. There were no significant differences in the activities of Cu-Zn, Mn SOD, CAT, and GPx between the C and MS groups, but in the MS Ovx group there was a statistically significant decrease in the activities of these enzymes when compared to MS and MS Ovx+E2. The increased lipid peroxidation and nonenzymatic antioxidant capacity found in MS Ovx was significantly decreased when compared to MS and MS Ovx+E2. In conclusion, the removal of E2 by ovariectomy decreases the activity of the antioxidant enzymes in the intra-abdominal tissue of MS female rats; this is reflected by increased lipid peroxidation and decreased nonenzymatic antioxidant capacity.

  6. Disruption of AtWNK8 Enhances Tolerance of Arabidopsis to Salt and Osmotic Stresses via Modulating Proline Content and Activities of Catalase and Peroxidase

    Directory of Open Access Journals (Sweden)

    Hong Liao

    2013-03-01

    Full Text Available With no lysine kinases (WNKs play important roles in plant growth and development. However, its role in salt and osmotic stress tolerance is unclear. Here, we report that AtWNK8 is mainly expressed in primary root, hypocotyl, stamen and pistil and is induced by NaCl and sorbitol treatment. Compared to the wild-type, the T-DNA knock-out wnk8 mutant was more tolerant to severe salinity and osmotic stresses, as indicated by 27% and 198% more fresh weight in the NaCl and sorbitol treatment, respectively. The wnk8 mutant also accumulated 1.43-fold more proline than the wild-type in the sorbitol treatment. Under NaCl and sorbitol stresses, catalase (CAT activity in wnk8 mutant was 1.92- and 3.7-times of that in Col-0, respectively. Similarly, under salt and osmotic stress conditions, peroxidase (POD activities in wnk8 mutant were 1.81- and 1.58-times of that in Col-0, respectively. Taken together, we revealed that maintaining higher CAT and POD activities might be one of the reasons that the disruption of AtWNK8 enhances the tolerance to salt stress, and accumulating more proline and higher activities of CAT and POD might result in the higher tolerance of WNK8 to osmotic stress.

  7. Catalytic properties of three catalases from Kohlrabi ( Brassica ...

    African Journals Online (AJOL)

    Catalase (EC 1.11.1.6) was extracted from kohlrabi bulbs (Brassica oleracea gongylodes) with 0.05 M phosphate buffer, pH 7.0. On the basis of kinetic studies and activity stain for catalase, only three isoenzymes of catalases were detected in kohlrabi bulbs extract with pH optima at 4.5, 6.5 and 10. Highest catalytic ...

  8. Catalytic properties of three catalases from Kohlrabi (Brassica ...

    African Journals Online (AJOL)

    SERVER

    2008-02-19

    Feb 19, 2008 ... Catalase (EC 1.11.1.6) was extracted from kohlrabi bulbs (Brassica oleracea gongylodes) with 0.05 M phosphate buffer, pH 7.0. On the basis of kinetic studies and activity stain for catalase, only three isoenzymes of catalases were detected in kohlrabi bulbs extract with pH optima at 4.5, 6.5 and 10. Highest ...

  9. Catalase activity is stimulated by H2O2 in rich culture medium and is required for H2O2 resistance and adaptation in yeast

    OpenAIRE

    Dorival Martins; Ann M. English

    2014-01-01

    Catalases are efficient scavengers of H2O2 and protect cells against H2O2 stress. Examination of the H2O2 stimulon in Saccharomyces cerevisiae revealed that the cytosolic catalase T (Ctt1) protein level increases 15-fold on H2O2 challenge in synthetic complete media although previous work revealed that deletion of the CCT1 or CTA1 genes (encoding peroxisomal/mitochondrial catalase A) does not increase the H2O2 sensitivity of yeast challenged in phosphate buffer (pH 7.4). This we attributed to...

  10. Development of lyophilization cycle and effect of excipients on the stability of catalase during lyophilization

    Science.gov (United States)

    Lale, Shantanu V; Goyal, Monu; Bansal, Arvind K

    2011-01-01

    Introduction: The purpose of the present study was to screen excipients such as amino acids and non-aqueous solvents for their stabilizing effect on catalase, a model protein, for lyophilization. The present study also includes optimization of lyophilization cycle for catalase formulations, which is essential from the commercial point of view, since lyophilization is an extremely costly process. Materials and Methods: Activity of catalase was determined using catalase activity assay. Differential scanning calorimetry was used to determine eutectic melting temperature of the frozen catalase solution, which is essential for the optimization of lyophilization cycle. Results: When catalase was lyophilized without excipients, it was found that about 65-78% of the initial activity of catalase was lost during the lyophilization process in a concentration dependent manner. The maximum stability of catalase during lyophilization was observed at pH 7.0. Amino acids like alanine, glycine, lysine, serine and 4-hydroxy proline showed strong stabilizing effect on catalase during lyophilization by protecting catalase activity above 95%, whereas valine and cysteine hydrochloride showed destabilizing effect on catalase. Non-aqueous solvents such as dimethyl formamide, dimethyl sulphoxide, polyethylene glycol (PEG) 200, PEG 400, PEG 600 and ethylene glycol also showed destabilizing effect on catalase during lyophilization. Conclusions: In order to prevent loss of catalase activity during lyophilization of catalase, use of amino acids like alanine, glycine, lysine, serine and 4-hydroxy proline in optimum concentration is highly advisable. PMID:23071946

  11. Dosing-Time Dependent Effects of Sodium Nitroprusside on Cerebral, Renal, and Hepatic Catalase Activity in Mice

    Directory of Open Access Journals (Sweden)

    Mamane Sani

    2015-01-01

    Full Text Available To investigate the time dependence of sodium nitroprusside- (NPS- induced oxidative effects, the authors study the variation of the antioxidant enzyme CAT activity in various tissues after the administration of a single 2.5 mg/kg dose of SNP or sodium chloride (NaCl 0.9%. For each of the two dosing times (1 and 13 hours after light onset, HALO, which correspond to the beginning of diurnal rest span and of nocturnal activity span of mice, resp., brain, kidney, and liver tissues were excised from animals at 0, 1, 3, 6, 9, 12, 24, and 36 h following the drug administration and CAT activity was assayed. The results suggest that SNP-induced stimulation of CAT activity is greater in all three tissues when the drug is administered at 1 HALO than at 13 HALO. Two-way ANOVA revealed that CAT activity significantly (P<0.004 varied as a function of the sampling time but not of the treatment in all three tissues. Moreover, a statistically significant (P<0.004 interaction between the organ sampling-time and the SNP treatment was revealed in kidney regardless of the dosing time, whereas a highly significant (P<0.0002 interaction was validated in liver only in animals injected at 13 HALO.

  12. Ethnobotanical review and pharmacological properties of selected medicinal plants in Brunei Darussalam: Litsea elliptica, Dillenia suffruticosa, Dillenia excelsa, Aidia racemosa, Vitex pinnata and Senna alata

    Directory of Open Access Journals (Sweden)

    May Poh Yik Goh

    2017-02-01

    Full Text Available The aim of the current study is to review the medicinal properties of the plants found in Brunei Darussalam namely Litsea elliptica, Dillenia suffruticosa, Dillenia excelsa, Aidia racemosa, Vitex pinnata and Senna alata. The known phytochemical constituents of these plants and their ability to bring about a range of biological activities are included in this review. These plants have been used traditionally for a multitude of diseases and illnesses. There is a lot of untapped potential in these medicinal plants which could cure multiple diseases.

  13. The protective effect of an aqueous extract from Smilax excelsa l ...

    African Journals Online (AJOL)

    The protective effect of an aqueous extract from Smilax excelsa l. against carbon tetrachloride-induced liver injury in rats. ... of various acute and chronic liver diseases, dietary antioxidants and drugs from herbal origins have been proved to be beneficial as therapeutic agents in reversing hepatotoxicity and oxidative stress.

  14. Optimization of extracellular catalase production from Aspergillus ...

    African Journals Online (AJOL)

    The studies of the effect of each variable and the establishment of a correlation between the response of enzyme activity and variables revealed that the link is a multiple linear regression form. The optimization was carried out through a simplex algorithm. The amount of extracellular catalase produced by the strain in the ...

  15. Establishment of Photo-aging In Vitro by Repetitive UVA Irradiation: Induction of Characteristic Markers of Senescence and its Prevention by PAPLAL with Potent Catalase Activity.

    Science.gov (United States)

    Yoshimoto, Satoshi; Yoshida, Moemi; Ando, Hideya; Ichihashi, Masamitsu

    2017-12-18

    To understand a role of UVA radiation in photo-aging of the skin, we established a model of photo-aging cells using cultured human dermal fibroblasts. Repeated low dose UVA radiation for 10 consecutive days induced senescence in fibroblasts, characterized with 1) increased level of senescence-associated β-galactosidase, 2) flattened large cell shape, 3) accumulation of reactive oxygen species, 4) yellowish coloration and 5) expression of p16. These were also observed in chronologically aged fibroblasts (doubling times >20), whereas none of these were detected in young cells (doubling times senescence. In addition, H 2 O 2 was produced in the culture medium by a single low dose of UVA irradiation. Further, PAPLAL, a nanoparticle of platinum and palladium having potent catalase-like activity, significantly delayed the onset of H 2 O 2 -induced cell senescence. The present study strongly indicates that repetitive short term UVA irradiation induces aging of cells possibly via H 2 O 2 and may be suppressed by potent anti-H 2 O 2 agents. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  16. Catalase and superoxide dismutase activities and the total protein content of protocorm-like bodies of Dendrobium sonia-28 subjected to vitrification.

    Science.gov (United States)

    Poobathy, Ranjetta; Sinniah, Uma Rani; Xavier, Rathinam; Subramaniam, Sreeramanan

    2013-07-01

    Dendrobium sonia-28 is an important ornamental orchid in the Malaysian flower industry. However, the genus faces both low germination rates and the risk of producing heterozygous progenies. Cryopreservation is currently the favoured long-term storage method for orchids with propagation problems. Vitrification, a frequently used cryopreservation technique, involves the application of pretreatments and cryoprotectants to protect and recover explants during and after storage in liquid nitrogen. However, cryopreservation may cause osmotic injuries and toxicity to cryopreserved explants from the use of highly concentrated additives, and cellular injuries from thawing, devitrification and ice formation. Reactive oxygen species (ROS), occurring during dehydration and cryopreservation, may also cause membrane damage. Plants possess efficient antioxidant systems such as the superoxide dismutase (SOD) and catalase (CAT) enzymes to scavenge ROS during low temperature stress. In this study, protocorm-like bodies (PLBs) of Dendrobium sonia-28 were assayed for the total protein content, and both SOD and CAT activities, at each stage of a vitrification exercise to observe for deleterious stages in the protocol. The results indicated that cryopreserved PLBs of Dendrobium sonia-28 underwent excessive post-thawing oxidative stress due to decreased levels of the CAT enzyme at the post-thawing recovery stage, which contributed to the poor survival rates of the cryopreserved PLBs.

  17. Scenarios concerning the impacts of electric energy sector privatization in the tariffs: the Excelsa case study; Cenarios sobre o impacto da privatizacao do setor eletrico nas tarifas: o caso da Excelsa

    Energy Technology Data Exchange (ETDEWEB)

    Pinguelli Rosa, Luiz; Hoffman, Carlos A.A. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia

    1995-12-31

    This paper presents relevant information concerning Excelsa, electric energy company of Espirito Santo State of Brazil, its costs and tariffs structure, legal aspects of its privatization process and scenarios concerning the tariffs evolution. 7 refs., 1 fig., 5 tabs.

  18. How old are large Brazil-nut trees (Bertholletia excelsa in the Amazon? Que idade podem alcançar as castanheiras (Bertholletia excelsa da Amazônia?

    Directory of Open Access Journals (Sweden)

    P.B. de Camargo

    1994-08-01

    Full Text Available The age of a large Brazil-nut tree (Bertholletia excelsa is measured by radiocarbon dating, and a discussion is made about their importance in the Amazon rain-forest ecosystem.A idade de uma castanheira (Bertholletia excelsa grande é medida por datação radiocarbônica e uma discussão é feita a respeito de sua importância no ecosistema da floresta amazônica.

  19. Hinokitiol Exerts Anticancer Activity through Downregulation of MMPs 9/2 and Enhancement of Catalase and SOD Enzymes: In Vivo Augmentation of Lung Histoarchitecture

    Directory of Open Access Journals (Sweden)

    Chien-Hsun Huang

    2015-09-01

    Full Text Available Melanoma is extremely resistant to chemotherapy and the death rate is increasing hastily worldwide. Extracellular matrix promotes the migration and invasion of tumor cells through the production of matrix metalloproteinase (MMP-2 and -9. Evidence has shown that natural dietary antioxidants are capable of inhibiting cancer cell growth. Our recent studies showed that hinokitiol, a natural bioactive compound, inhibited vascular smooth muscle cell proliferation and platelets aggregation. The present study is to investigate the anticancer efficacy of hinokitiol against B16-F10 melanoma cells via modulating tumor invasion factors MMPs, antioxidant enzymes in vitro. An in vivo mice model of histological investigation was performed to study the patterns of elastic and collagen fibers. Hinokitiol inhibited the expression and activity of MMPs-2 and -9 in B16-F10 melanoma cells, as measured by western blotting and gelatin zymography, respectively. An observed increase in protein expression of MMPs 2/9 in melanoma cells was significantly inhibited by hinokitiol. Notably, hinokitiol (1–5 μM increased the activities of antioxidant enzymes catalase (CAT and superoxide dismutase (SOD from the reduction in melanoma cells. Also, hinokitiol (2–10 µM concentration dependently reduced in vitro Fenton reaction induced hydroxyl radical (OH· formation. An in vivo study showed that hinokitiol treatment increased elastic fibers (EF, collagens dispersion, and improved alveolar alterations in the lungs of B16/F10 injected mice. Overall, our findings propose that hinokitiol may be a potent anticancer candidate through down regulation of MMPs 9/2, reduction of OH· production and enhancement of antioxidant enzymes SOD and CAT.

  20. Catalase vs peroxidase activity of a manganese(II) compound: identification of a Mn(III)-(mu-O)(2)-Mn(IV) reaction intermediate by electrospray ionization mass spectrometry and electron paramagnetic resonance spectroscopy.

    Science.gov (United States)

    Lessa, Josane A; Horn, Adolfo; Bull, Erika S; Rocha, Michelle R; Benassi, Mario; Catharino, Rodrigo R; Eberlin, Marcos N; Casellato, Annelise; Noble, Christoper J; Hanson, Graeme R; Schenk, Gerhard; Silva, Giselle C; Antunes, O A C; Fernandes, Christiane

    2009-05-18

    Herein, we report reactivity studies of the mononuclear water-soluble complex [Mn(II)(HPClNOL)(eta(1)-NO(3))(eta(2)-NO(3))] 1, where HPClNOL = 1-(bis-pyridin-2-ylmethyl-amino)-3-chloropropan-2-ol, toward peroxides (H(2)O(2) and tert-butylhydroperoxide). Both the catalase (in aqueous solution) and peroxidase (in CH(3)CN) activities of 1 were evaluated using a range of techniques including electronic absorption spectroscopy, volumetry (kinetic studies), pH monitoring during H(2)O(2) disproportionation, electron paramagnetic resonance (EPR), electrospray ionization mass spectrometry in the positive ion mode [ESI(+)-MS], and gas chromatography (GC). Electrochemical studies showed that 1 can be oxidized to Mn(III) and Mn(IV). The catalase-like activity of 1 was evaluated with and without pH control. The results show that the pH decreases when the reaction is performed in unbuffered media. Furthermore, the activity of 1 is greater in buffered than in unbuffered media, demonstrating that pH influences the activity of 1 toward H(2)O(2). For the reaction of 1 with H(2)O(2), EPR and ESI(+)-MS have led to the identification of the intermediate [Mn(III)Mn(IV)(mu-O)(2)(PClNOL)(2)](+). The peroxidase activity of 1 was also evaluated by monitoring cyclohexane oxidation, using H(2)O(2) or tert-butylhydroperoxide as the terminal oxidants. Low yields (<7%) were obtained for H(2)O(2), probably because it competes with 1 for the catalase-like activity. In contrast, using tert-butylhydroperoxide, up to 29% of cyclohexane conversion was obtained. A mechanistic model for the catalase activity of 1 that incorporates the observed lag phase in O(2) production, the pH variation, and the formation of a Mn(III)-(mu-O)(2)-Mn(IV) intermediate is proposed.

  1. Immobilization and characterization of bovine liver catalase on eggshell

    Directory of Open Access Journals (Sweden)

    ÖZLEM ALPTEKİN

    2008-06-01

    Full Text Available Bovine liver catalase immobilized on eggshell particles was characterized and the reusability of the immobilized catalase was investigated in a batch type reactor. For immobilized catalase onto ground eggshell (ICATG, the optimum initial amount of catalase was 85 mg g-1 of eggshells, the optimum pH was 6.0 (75 mM citrate buffer and the temperature was 30 °C. The Vmax and Km values of ICATG were determined as 29.1±1.2 U/mg of protein and 41.9±2.7 mM, respectively. The reusability of ICATG was tested and the remaining activity of ICATG was found to be 73 % of the initial activity after 80 cycles of batch operation. The amount of catalase bound onto the carrier was estimated by using the results of induced coupled plasma measurements. The catalytic efficiencies (kcat/Km of free catalase and ICATG were found to be 1.4´106 and 2.8´103 dm3 s-1 mol-1, respectively. Catalase immobilization onto eggshell is economic and has good reusability. Hence, it can be concluded that eggshell is an efficient carrier for immobilizing catalase.

  2. Influence of the geometry around the manganese ion on the peroxidase and catalase activities of Mn(III)-Schiff base complexes.

    Science.gov (United States)

    Vázquez-Fernández, M Ángeles; Bermejo, Manuel R; Fernández-García, M Isabel; González-Riopedre, Gustavo; Rodríguez-Doutón, M Jesús; Maneiro, Marcelino

    2011-12-01

    The peroxidase and catalase activities of eighteen manganese-Schiff base complexes have been studied. A correlation between the structure of the complexes and their catalytic activity is discussed on the basis of the variety of systems studied. Complexes 1-18 have the general formulae [MnL(n)(D)(2)](X)(H(2)O/CH(3)OH)(m), where L(n)=L(1)-L(13); D=H(2)O, CH(3)OH or Cl; m=0-2.5 and X=NO(3)(-), Cl(-), ClO(4)(-), CH(3)COO(-), C(2)H(5)COO(-) or C(5)H(11)COO(-). The dianionic tetradentate Schiff base ligands H(2)L(n) are the result of the condensation of different substituted (OMe-, OEt-, Br-, Cl-) hydroxybenzaldehyde with diverse diamines (1,2-diaminoethane for H(2)L(1)-H(2)L(2); 1,2-diamino-2-methylethane for H(2)L(3)-H(2)L(4); 1,2-diamino-2,2-dimethylethane for H(2)L(5); 1,2-diphenylenediamine for H(2)L(6)-H(2)L(7); 1,3-diaminopropane for H(2)L(8)-H(2)L(11); 1,3-diamino-2,2-dimethylpropane for H(2)L(12)-H(2)L(13)). The new Mn(III) complexes [MnL(1)(H(2)O)Cl](H(2)O)(2.5) (2), [MnL(2)(H(2)O)(2)](NO(3))(H(2)O) (4), [MnL(6)(H(2)O)(2)][MnL(6)(CH(3)OH)(H(2)O)](NO(3))(2)(CH(3)OH) (8), [MnL(6)(H(2)O)(OAc)](H(2)O) (9) and [MnL(7)(H(2)O)(2)](NO(3))(CH(3)OH)(2) (12) were isolated and characterised by elemental analysis, magnetic susceptibility and conductivity measurements, redox studies, ESI spectrometry and UV, IR, paramagnetic (1)H NMR, and EPR spectroscopies. X-ray crystallographic studies of these complexes and of the ligand H(2)L(6) are also reported. The crystal structures of the rest of the complexes have been previously published and herein we have only revised their study by those techniques still not reported (EPR and (1)H NMR for some of these compounds) and which help to establish their structures in solution. Complexes 1-12 behave as more efficient mimics of peroxidase or catalase in contrast with 13-18. The analysis between the catalytic activity and the structure of the compounds emphasises the significance of the existence of a vacant or a labile position in the

  3. The Green Tea Component (--Epigallocatechin-3-Gallate Sensitizes Primary Endothelial Cells to Arsenite-Induced Apoptosis by Decreasing c-Jun N-Terminal Kinase-Mediated Catalase Activity.

    Directory of Open Access Journals (Sweden)

    Jee-Youn Kim

    Full Text Available The green tea component (--epigallocatechin-3-gallate (EGCG has been shown to sensitize many different types of cancer cells to anticancer drug-induced apoptosis, although it protects against non-cancerous primary cells against toxicity from certain conditions such as exposure to arsenic (As or ultraviolet irradiation. Here, we found that EGCG promotes As-induced toxicity of primary-cultured bovine aortic endothelial cells (BAEC at doses in which treatment with each chemical alone had no such effect. Increased cell toxicity was accompanied by an increased condensed chromatin pattern and fragmented nuclei, cleaved poly(ADP-ribose polymerase (PARP, activity of the pro-apoptotic enzymes caspases 3, 8 and 9, and Bax translocation into mitochondria, suggesting the involvement of an apoptotic signaling pathway. Fluorescence activated cell sorting analysis revealed that compared with EGCG or As alone, combined EGCG and As (EGCG/As treatment significantly induced production of reactive oxygen species (ROS, which was accompanied by decreased catalase activity and increased lipid peroxidation. Pretreatment with N-acetyl-L-cysteine or catalase reversed EGCG/As-induced caspase activation and EC toxicity. EGCG/As also increased the phosphorylation of c-Jun N-terminal kinase (JNK, which was not reversed by catalase. However, pretreatment with the JNK inhibitor SP600125 reversed all of the observed effects of EGCG/As, suggesting that JNK may be the most upstream protein examined in this study. Finally, we also found that all the observed effects by EGCG/As are true for other types of EC tested. In conclusion, this is firstly to show that EGCG sensitizes non-cancerous EC to As-induced toxicity through ROS-mediated apoptosis, which was attributed at least in part to a JNK-activated decrease in catalase activity.

  4. Development of lyophilization cycle and effect of excipients on the stability of catalase during lyophilization

    OpenAIRE

    Lale, Shantanu V; Goyal, Monu; Bansal, Arvind K

    2011-01-01

    Introduction: The purpose of the present study was to screen excipients such as amino acids and non-aqueous solvents for their stabilizing effect on catalase, a model protein, for lyophilization. The present study also includes optimization of lyophilization cycle for catalase formulations, which is essential from the commercial point of view, since lyophilization is an extremely costly process. Materials and Methods: Activity of catalase was determined using catalase activity assay. Differen...

  5. 7 CFR 58.432 - Catalase.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Catalase. 58.432 Section 58.432 Agriculture... Material § 58.432 Catalase. The catalase preparation shall be a stable, buffered solution, neutral in pH, having a potency of not less than 100 Keil units per milliliter. The source of the catalase, its...

  6. Correlation between acid, TBA, peroxide and iodine values, catalase and glutathione peroxidase activities of chicken, cattle and camel meat during refrigerated storage

    OpenAIRE

    Hamid Reza Gheisari

    2011-01-01

    The aim of this study was correlation determination between fat putrefaction indices and antioxidative enzymes in chicken, cattle and camel meat during refrigerated storage. Longissimus dorsi muscle of three Iranian dromedary one humped camel and three Holstein cattle and breast muscle of three broiler breeder chicken were obtained from the carcasses 3 days postmortem. The samples were ground and stored at 4 °C for 0, 2, or 4 days. Peroxide, TBA, acid and iodine values, catalase and ...

  7. Regulation of catalase expression in healthy and cancerous cells.

    Science.gov (United States)

    Glorieux, Christophe; Zamocky, Marcel; Sandoval, Juan Marcelo; Verrax, Julien; Calderon, Pedro Buc

    2015-10-01

    Catalase is an important antioxidant enzyme that dismutates hydrogen peroxide into water and molecular oxygen. The catalase gene has all the characteristics of a housekeeping gene (no TATA box, no initiator element sequence, high GC content in promoter) and a core promoter that is highly conserved among species. We demonstrate in this review that within this core promoter, the presence of DNA binding sites for transcription factors, such as NF-Y and Sp1, plays an essential role in the positive regulation of catalase expression. Additional transcription factors, such as FoxO3a, are also involved in this regulatory process. There is strong evidence that the protein Akt/PKB in the PI3K signaling pathway plays a major role in the expression of catalase by modulating the activity of FoxO3a. Over the past decade, other transcription factors (PPARγ, Oct-1, etc.), as well as genetic, epigenetic, and posttranscriptional processes, have emerged as crucial contributors to the regulation of catalase expression. Altered expression levels of catalase have been reported in cancer tissues compared to their normal counterparts. Deciphering the molecular mechanisms that regulate catalase expression could, therefore, be of crucial importance for the future development of pro-oxidant cancer chemotherapy. Copyright © 2015. Published by Elsevier Inc.

  8. Novel insights in mammalian catalase heme maturation: effect of NO and thioredoxin-1.

    Science.gov (United States)

    Chakravarti, Ritu; Gupta, Karishma; Majors, Alana; Ruple, Lisa; Aronica, Mark; Stuehr, Dennis J

    2015-05-01

    Catalase is a tetrameric heme-containing enzyme with essential antioxidant functions in biology. Multiple factors including nitric oxide (NO) have been shown to attenuate its activity. However, the possible impact of NO in relation to the maturation of active catalase, including its heme acquisition and tetramer formation, has not been investigated. We found that NO attenuates heme insertion into catalase in both short-term and long-term incubations. The NO inhibition in catalase heme incorporation was associated with defective oligomerization of catalase, such that inactive catalase monomers and dimers accumulated in place of the mature tetrameric enzyme. We also found that GAPDH plays a key role in mediating these NO effects on the structure and activity of catalase. Moreover, the NO sensitivity of catalase maturation could be altered up or down by manipulating the cellular expression level or activity of thioredoxin-1, a known protein-SNO denitrosylase enzyme. In a mouse model of allergic inflammatory asthma, we found that lungs from allergen-challenged mice contained a greater percentage of dimeric catalase relative to tetrameric catalase in the unchallenged control, suggesting that the mechanisms described here are in play in the allergic asthma model. Together, our study shows how maturation of active catalase can be influenced by NO, S-nitrosylated GAPDH, and thioredoxin-1, and how maturation may become compromised in inflammatory conditions such as asthma. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Nut Production in Bertholletia excelsa across a Logged Forest Mosaic: Implications for Multiple Forest Use.

    Directory of Open Access Journals (Sweden)

    Cara A Rockwell

    Full Text Available Although many examples of multiple-use forest management may be found in tropical smallholder systems, few studies provide empirical support for the integration of selective timber harvesting with non-timber forest product (NTFP extraction. Brazil nut (Bertholletia excelsa, Lecythidaceae is one of the world's most economically-important NTFP species extracted almost entirely from natural forests across the Amazon Basin. An obligate out-crosser, Brazil nut flowers are pollinated by large-bodied bees, a process resulting in a hard round fruit that takes up to 14 months to mature. As many smallholders turn to the financial security provided by timber, Brazil nut fruits are increasingly being harvested in logged forests. We tested the influence of tree and stand-level covariates (distance to nearest cut stump and local logging intensity on total nut production at the individual tree level in five recently logged Brazil nut concessions covering about 4000 ha of forest in Madre de Dios, Peru. Our field team accompanied Brazil nut harvesters during the traditional harvest period (January-April 2012 and January-April 2013 in order to collect data on fruit production. Three hundred and ninety-nine (approximately 80% of the 499 trees included in this study were at least 100 m from the nearest cut stump, suggesting that concessionaires avoid logging near adult Brazil nut trees. Yet even for those trees on the edge of logging gaps, distance to nearest cut stump and local logging intensity did not have a statistically significant influence on Brazil nut production at the applied logging intensities (typically 1-2 timber trees removed per ha. In one concession where at least 4 trees ha-1 were removed, however, the logging intensity covariate resulted in a marginally significant (0.09 P value, highlighting a potential risk for a drop in nut production at higher intensities. While we do not suggest that logging activities should be completely avoided in Brazil

  10. Nut Production in Bertholletia excelsa across a Logged Forest Mosaic: Implications for Multiple Forest Use.

    Science.gov (United States)

    Rockwell, Cara A; Guariguata, Manuel R; Menton, Mary; Arroyo Quispe, Eriks; Quaedvlieg, Julia; Warren-Thomas, Eleanor; Fernandez Silva, Harol; Jurado Rojas, Edwin Eduardo; Kohagura Arrunátegui, José Andrés Hideki; Meza Vega, Luis Alberto; Revilla Vera, Olivia; Quenta Hancco, Roger; Valera Tito, Jonatan Frank; Villarroel Panduro, Betxy Tabita; Yucra Salas, Juan José

    2015-01-01

    Although many examples of multiple-use forest management may be found in tropical smallholder systems, few studies provide empirical support for the integration of selective timber harvesting with non-timber forest product (NTFP) extraction. Brazil nut (Bertholletia excelsa, Lecythidaceae) is one of the world's most economically-important NTFP species extracted almost entirely from natural forests across the Amazon Basin. An obligate out-crosser, Brazil nut flowers are pollinated by large-bodied bees, a process resulting in a hard round fruit that takes up to 14 months to mature. As many smallholders turn to the financial security provided by timber, Brazil nut fruits are increasingly being harvested in logged forests. We tested the influence of tree and stand-level covariates (distance to nearest cut stump and local logging intensity) on total nut production at the individual tree level in five recently logged Brazil nut concessions covering about 4000 ha of forest in Madre de Dios, Peru. Our field team accompanied Brazil nut harvesters during the traditional harvest period (January-April 2012 and January-April 2013) in order to collect data on fruit production. Three hundred and ninety-nine (approximately 80%) of the 499 trees included in this study were at least 100 m from the nearest cut stump, suggesting that concessionaires avoid logging near adult Brazil nut trees. Yet even for those trees on the edge of logging gaps, distance to nearest cut stump and local logging intensity did not have a statistically significant influence on Brazil nut production at the applied logging intensities (typically 1-2 timber trees removed per ha). In one concession where at least 4 trees ha-1 were removed, however, the logging intensity covariate resulted in a marginally significant (0.09) P value, highlighting a potential risk for a drop in nut production at higher intensities. While we do not suggest that logging activities should be completely avoided in Brazil nut rich

  11. Nut Production in Bertholletia excelsa across a Logged Forest Mosaic: Implications for Multiple Forest Use

    Science.gov (United States)

    Rockwell, Cara A.; Guariguata, Manuel R.; Menton, Mary; Arroyo Quispe, Eriks; Quaedvlieg, Julia; Warren-Thomas, Eleanor; Fernandez Silva, Harol; Jurado Rojas, Edwin Eduardo; Kohagura Arrunátegui, José Andrés Hideki; Meza Vega, Luis Alberto; Revilla Vera, Olivia; Valera Tito, Jonatan Frank; Villarroel Panduro, Betxy Tabita; Yucra Salas, Juan José

    2015-01-01

    Although many examples of multiple-use forest management may be found in tropical smallholder systems, few studies provide empirical support for the integration of selective timber harvesting with non-timber forest product (NTFP) extraction. Brazil nut (Bertholletia excelsa, Lecythidaceae) is one of the world’s most economically-important NTFP species extracted almost entirely from natural forests across the Amazon Basin. An obligate out-crosser, Brazil nut flowers are pollinated by large-bodied bees, a process resulting in a hard round fruit that takes up to 14 months to mature. As many smallholders turn to the financial security provided by timber, Brazil nut fruits are increasingly being harvested in logged forests. We tested the influence of tree and stand-level covariates (distance to nearest cut stump and local logging intensity) on total nut production at the individual tree level in five recently logged Brazil nut concessions covering about 4000 ha of forest in Madre de Dios, Peru. Our field team accompanied Brazil nut harvesters during the traditional harvest period (January-April 2012 and January-April 2013) in order to collect data on fruit production. Three hundred and ninety-nine (approximately 80%) of the 499 trees included in this study were at least 100 m from the nearest cut stump, suggesting that concessionaires avoid logging near adult Brazil nut trees. Yet even for those trees on the edge of logging gaps, distance to nearest cut stump and local logging intensity did not have a statistically significant influence on Brazil nut production at the applied logging intensities (typically 1–2 timber trees removed per ha). In one concession where at least 4 trees ha-1 were removed, however, the logging intensity covariate resulted in a marginally significant (0.09) P value, highlighting a potential risk for a drop in nut production at higher intensities. While we do not suggest that logging activities should be completely avoided in Brazil nut rich

  12. Cloning, Expression, and Characterization of a Novel Thermophilic Monofunctional Catalase from Geobacillus sp. CHB1.

    Science.gov (United States)

    Jia, Xianbo; Chen, Jichen; Lin, Chenqiang; Lin, Xinjian

    2016-01-01

    Catalases are widely used in many scientific areas. A catalase gene (Kat) from Geobacillus sp. CHB1 encoding a monofunctional catalase was cloned and recombinant expressed in Escherichia coli (E. coli), which was the first time to clone and express this type of catalase of genus Geobacillus strains as far as we know. This Kat gene was 1,467 bp in length and encoded a catalase with 488 amino acid residuals, which is only 81% similar to the previously studied Bacillus sp. catalase in terms of amino acid sequence. Recombinant catalase was highly soluble in E. coli and made up 30% of the total E. coli protein. Fermentation broth of the recombinant E. coli showed a high catalase activity level up to 35,831 U/mL which was only lower than recombinant Bacillus sp. WSHDZ-01 among the reported catalase production strains. The purified recombinant catalase had a specific activity of 40,526 U/mg and K m of 51.1 mM. The optimal reaction temperature of this recombinant enzyme was 60°C to 70°C, and it exhibited high activity over a wide range of reaction temperatures, ranging from 10°C to 90°C. The enzyme retained 94.7% of its residual activity after incubation at 60°C for 1 hour. High yield and excellent thermophilic properties are valuable features for this catalase in industrial applications.

  13. A Twist on Measuring Catalase

    Science.gov (United States)

    Bryer, Pamela

    2016-01-01

    "Catalase," an enzyme found in both plant and animal cells, prevents the accumulation of toxic levels of hydrogen peroxide (H[subscript 2]O[subscript 2]) by catalyzing its decomposition to water and oxygen gas. Because this enzyme is ubiquitous, it is frequently used in high school biology laboratories to explore enzyme reactions. This…

  14. Structural analysis of catalase from two Musa accessions, FHIA18 and Williams, and from Ravenala madagascariensis.

    Science.gov (United States)

    Khoyratty, Sher-ullah S S; Souza, Manoel T; Jaufeerally-Fakim, Yasmina

    2008-01-01

    Nucleotide sequences of catalase were obtained following amplification using specific primers and were blasted against Musa acuminata catalase 2 mRNA from NCBI (157418810). Clustering of the amino acid sequences from NCBI was done using Clustal X. The latter revealed that FHIA18 catalase is more related to Ravenala madagascariensis (Musa relative) catalase while the Williams catalase is more related to a clade containing a Musa acuminata (Musa ancestor) catalase from NCBI. The tertiary structures and the catalase consensus functional sites, based on the Pseudomonas syringae catalase structural template, were obtained for FHIA18, Williams, Ravenala madagascariensis and Musa acuminata catalases. They were found to differ slightly. Using known features of catalase active sites, four pre-requisite criteria were defined to find such sites: (1) Position of tyrosine axial to heme determined by X-ray diffraction, (2) 7 conserved amino acids in the active site found by sequence alignment, (3) favourable docking energy, and (4) presence of an unobstructed long tunnel that leads the ligand to the active site. Two differing potential docking sites were found for both FHIA18 and Williams that fit a maximum number of criteria. In terms of 1D sequence, the region of the docking site for Williams is within the catalase domains as seen upon NCBI blast. The counterpart of FHIA18 for the same region is not. This sequence difference between FHIA18 and Williams affects the best docking site in FHIA18 and Williams in silico.

  15. Functional characterization of fifteen hundred transcripts from Ziarat juniper (Juniperus excelsa M.Bieb

    Directory of Open Access Journals (Sweden)

    Humaira Abdul Wahid

    2016-11-01

    Full Text Available Background: Ziarat juniper (Juniperus excelsa M.Bieb is an evergreen and dominant species of Balochistan juniper forests. This forest is providing many benefits to regional ecosystems and surrounding populations. No functional genomics study is reported for this important juniper plant. This research is aimed to characterize the Ziarat juniper functional genome based on the analyses of 1500 transcripts. Methods: Total RNA from shoot of Juniperus excelsa was extracted and subjected for transcriptome sequencing using Illumina HiSeq 2000 with the service from Macrogen, Inc., South Korea. The Illumina sequenced data was subjected to bioinformatics analysis. Quality assessment and data filtration was performed for the removal of low-quality reads, ambiguous reads and adaptor sequences. The high-quality clean reads data was deposited in the Sequence Read Archive (SRA at NCBI, and used for downstream processes. Fifteen hundred transcripts were randomly chosen and used for functional characterization. Results: As a result of homology search 80.3% transcripts showed significant similarities and were placed in significant similarities category, 19.3% transcripts showed low similarities and assigned to the ‘‘unclassified’’ category while 0.4% transcripts are defined as no hits. The functional characterization results showed that most (18% of the transcripts are involved in metabolism, followed by 11.7% in transcription and 11.5% as structural protein. 8.8% transcripts are engaged in stress response, whereas the transcripts involved in growth and development constituted 6.7%. Transcripts involved in signal transduction represented 5.6%, while 3.5% facilitating transport and 34.1% are involved in hypothetical functions. Conclusion: The functional annotation data produced in this study will be very useful for future functional genome analysis of Juniperus excelsa.

  16. Identification of a Catalase-Phenol Oxidase in Betalain Biosynthesis in Red Amaranth (Amaranthus cruentus)

    Science.gov (United States)

    Teng, Xiao-Lu; Chen, Ning; Xiao, Xing-Guo

    2016-01-01

    Betalains are a group of nitrogen-containing pigments that color plants in most families of Caryophyllales. Their biosynthesis has long been proposed to begin with hydroxylation of L-tyrosine to L-DOPA through monophenolase activity of tyrosinase, but biochemical evidence in vivo remains lacking. Here we report that a Group 4 catalase, catalase-phenol oxidase (named as AcCATPO), was identified, purified and characterized from leaves of Amaranthus cruentus, a betalain plant. The purified enzyme appeared to be a homotrimeric protein composed of subunits of about 58 kDa, and demonstrated not only the catalase activity toward H2O2, but also the monophenolase activity toward L-tyrosine and diphenolase activity toward L-DOPA. Its catalase and phenol oxidase activities were inhibited by common classic catalase and tyrosinase inhibitors, respectively. All its peptide fragments identified by nano-LC-MS/MS were targeted to catalases, and matched with a cDNA-encoded polypeptide which contains both classic catalase and phenol oxidase active sites. These sites were also present in catalases of non-betalain plants analyzed. AcCATPO transcript abundance was positively correlated with the ratio of betaxanthin to betacyanin in both green and red leaf sectors of A. tricolor. These data shows that the fourth group catalase, catalase-phenol oxidase, is present in plant, and might be involved in betaxanthin biosynthesis. PMID:26779247

  17. Water uptake, priming, drying and storage effects inCassia excelsa Schrad seeds

    OpenAIRE

    Jeller,H.; Perez,S. C. J. G. A.; Raizer,J.

    2003-01-01

    The aims of this study were to evaluate the effects of osmotic potential on the water uptake curvein Cassia excelsa seeds and use the results to analyze the effects of dehydration and storage on primed seed germination. Seeds were imbibed in distillad water and polyethylene glicol (PEG 6000) osmotic solutions at -0.2, -0.4, and -0.6 MPa, at 20ºC. The radicle emergence and seed moisture content were evaluated at 6-hour intervals during 240 hours. Afterwards, seeds were primed in distillad wate...

  18. Preparation of highly efficient manganese catalase mimics.

    Science.gov (United States)

    Triller, Michael U; Hsieh, Wen-Yuan; Pecoraro, Vincent L; Rompel, Annette; Krebs, Bernt

    2002-10-21

    The series of compounds [Mn(bpia)(mu-OAc)](2)(ClO(4))(2) (1), [Mn(2)(bpia)(2)(muO)(mu-OAc)](ClO(4))(3).CH(3)CN (2), [Mn(bpia)(mu-O)](2)(ClO(4))(2)(PF(6)).2CH(3)CN (3), [Mn(bpia)(Cl)(2)](ClO)(4) (4), and [(Mn(bpia)(Cl))(2)(mu-O)](ClO(4))(2).2CH(3)CN (5) (bpia = bis(picolyl)(N-methylimidazol-2-yl)amine) represents a structural, spectroscopic, and functional model system for manganese catalases. Compounds 3 and 5 have been synthesized from 2 via bulk electrolysis and ligand exchange, respectively. All complexes have been structurally characterized by X-ray crystallography and by UV-vis and EPR spectroscopies. The different bridging ligands including the rare mono-mu-oxo and mono-mu-oxo-mono-mu-carboxylato motifs lead to a variation of the Mn-Mn separation across the four binuclear compounds of 1.50 A (Mn(2)(II,II) = 4.128 A, Mn(2)(III,III) = 3.5326 and 3.2533 A, Mn(2)(III,IV) = 2.624 A). Complexes 1, 2, and 3 are mimics for the Mn(2)(II,II), the Mn(2)(III,III), and the Mn(2)(III,IV) oxidation states of the native enzyme. UV-vis spectra of these compounds show similarities to those of the corresponding oxidation states of manganese catalase from Thermus thermophilus and Lactobacillus plantarum. Compound 2 exhibits a rare example of a Jahn-Teller compression. While complexes 1 and 3 are efficient catalysts for the disproportionation of hydrogen peroxide and contain an N(4)O(2) donor set, 4 and 5 show no catalase activity. These complexes have an N(4)Cl(2) and N(4)OCl donor set, respectively, and serve as mimics for halide inhibited manganese catalases. Cyclovoltammetric data show that the substitution of oxygen donor atoms with chloride causes a shift of redox potentials to more positive values. To our knowledge, complex 1 is the most efficient binuclear functional manganese catalase mimic exhibiting saturation kinetics to date.

  19. Characterization of a cDNA encoding cottonseed catalase.

    Science.gov (United States)

    Ni, W; Turley, R B; Trelease, R N

    1990-06-21

    A 1.7 kb cDNA clone was isolated from our lambda gt11 library constructed from poly(A) RNA of 24-h-old cotyledons. The cDNA encodes a full-length catalase peptide (492 amino acid residues). The calculated molecular mass is 56,800, similar to that determined for purified enzyme (57,000 SDS-PAGE). Among higher plant catalases, this cotton catalase shows the highest amino acid sequence identity (85%) to the subunit of homotetrameric maize CAT 1, a developmental counterpart to the homotetrameric CAT A isoform of cotton seeds. Comparison of sequences from cotton, sweet potato, maize CAT 1, and yeast with bovine catalase revealed that the amino acid residues and regions that are involved in catalytic activity and/or required to maintain basic catalase structure, are highly conserved. The C-terminus region, which has the lowest nucleotide sequence identity between plant and mammalian catalases, does not terminate with a tripeptide, S-K/R/H-L, a putative targeting signal for peroxisomal proteins.

  20. Manganese Oxidation State Assignment for Manganese Catalase.

    Science.gov (United States)

    Beal, Nathan J; O'Malley, Patrick J

    2016-04-06

    The oxidation state assignment of the manganese ions present in the superoxidized manganese (III/IV) catalase active site is determined by comparing experimental and broken symmetry density functional theory calculated (14)N, (17)O, and (1)H hyperfine couplings. Experimental results have been interpreted to indicate that the substrate water is coordinated to the Mn(III) ion. However, by calculating hyperfine couplings for both scenarios we show that water is coordinated to the Mn(IV) ion and that the assigned oxidation states of the two manganese ions present in the site are the opposite of that previously proposed based on experimental measurements alone.

  1. Resuscitation effects of catalase on airborne bacteria.

    OpenAIRE

    Marthi, B; Shaffer, B T; Lighthart, B; Ganio, L

    1991-01-01

    Catalase incorporation into enumeration media caused a significant increase (greater than 63%) in the colony-forming abilities of airborne bacteria. Incubation for 30 to 60 min of airborne bacteria in collection fluid containing catalase caused a greater than 95% increase in colony-forming ability. However, catalase did not have any effects on enumeration at high relative humidities (80 to 90%).

  2. THE BRAZIL NUT TREE (BERTHOLLETIA EXCELSA HUMB. & BONPL. (LECYTHIDACEAE: IMPORTANCE AND BIOLOGICAL INTERACTIONS

    Directory of Open Access Journals (Sweden)

    L. Santos-Silva

    2017-12-01

    Full Text Available The Brazil nut (Bertholletia excelsa is a species of tree native to the Amazon region. The exploitation of its wood and fruit provides significant economic value. Due to this important economic value, different studies related to the Brazil nut tree provide relevant information about the beneficial and harmful relationships between the tree and other organisms. However, such information is scattered and difficult to access. The objective of this study was to compile the available information on the different relationships between the Brazil nut tree and other organisms to support future studies and strategies to better manage the resources and benefits of this tree. We found 194 species that interact with the Brazil nut tree. These species consisted of predators, dispersers, competitors, pollinators, floral visitors, pathogens and microorganisms. Although exploitation of the Brazil nut has occurred for many decades in native forests, the production of seedlings and cultivation of the species are relatively recent events, with few occurrences of pests and diseases recorded for B.excelsa in native forests and plantations. In contrast, pollinators, floral visitors and dispersers were recorded in abundance, as well as contaminating fungi that deteriorate the nut. Considering the volume and diversity of records it is possible to infer that there is a need for constant monitoring of the Brazil nut in plantations and natural areas, as well as to encourage research related to the specific biotic interactions of Brazil nuts.

  3. Uncovering spatial patterns in the natural and human history of Brazil nut (Bertholletia excelsa) across the Amazon Basin

    NARCIS (Netherlands)

    Thomas, E.; Alcázar Caicedo, C.; McMichael, C.H.; Corvera, R.; Loo, J.

    2015-01-01

    Aim Our goal was to test the hypothesis that ancient humans substantially contributed to shaping the current distribution of Brazil nut (Bertholletia excelsa), an Amazonian tree species that has been important for human livelihoods since pre-Columbian times. We scrutinized the putative association

  4. Purification and Characterization of Catalase from Marine Bacterium Acinetobacter sp. YS0810

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    Xinhua Fu

    2014-01-01

    Full Text Available The catalase from marine bacterium Acinetobacter sp. YS0810 (YS0810CAT was purified and characterized. Consecutive steps were used to achieve the purified enzyme as follows: ethanol precipitation, DEAE Sepharose ion exchange, Superdex 200 gel filtration, and Resource Q ion exchange. The active enzyme consisted of four identical subunits of 57.256 kDa. It showed a Soret peak at 405 nm, indicating the presence of iron protoporphyrin IX. The catalase was not apparently reduced by sodium dithionite but was inhibited by 3-amino-1,2,4-triazole, hydroxylamine hydrochloride, and sodium azide. Peroxidase-like activity was not found with the substrate o-phenylenediamine. So the catalase was determined to be a monofunctional catalase. N-terminal amino acid of the catalase analysis gave the sequence SQDPKKCPVTHLTTE, which showed high degree of homology with those of known catalases from bacteria. The analysis of amino acid sequence of the purified catalase by matrix-assisted laser desorption ionization time-of-flight mass spectrometry showed that it was a new catalase, in spite of its high homology with those of known catalases from other bacteria. The catalase showed high alkali stability and thermostability.

  5. Roles of Catalase and Trehalose in the Protection from Hydrogen Peroxide Toxicity in Saccharomyces cerevisiae.

    Science.gov (United States)

    Nishimoto, Takuto; Watanabe, Takeru; Furuta, Masakazu; Kataoka, Michihiko; Kishida, Masao

    2016-01-01

    The roles of catalase and trehalose in Saccharomyces cerevisiae subject to hydrogen peroxide (H2O2) treatment were examined by measuring the catalase activity and intracellular trehalose levels in mutants lacking catalase or trehalose synthetase. Intracellular trehalose was elevated but the survival rate after H2O2 treatment remained low in mutants with deletion of the Catalase T gene. On the other hand, deletion of the trehalose synthetase gene increased the catalase activity in mutated yeast to levels higher than those in the wild-type strain, and these mutants exhibited some degree of tolerance to H2O2 treatment. These results suggest that Catalase T is critical in the yeast response to oxidative damage caused by H2O2 treatment, but trehalose also plays a role in protection against H2O2 treatment.

  6. Nitrite and nitroso compounds can serve as specific catalase inhibitors.

    Science.gov (United States)

    Titov, Vladimir Yu; Osipov, Anatoly N

    2017-03-01

    We present evidence that nitrite and nitrosothiols, nitrosoamines and non-heme dinitrosyl iron complexes can reversibly inhibit catalase with equal effectiveness. Catalase activity was evaluated by the permanganatometric and calorimetric assays. This inhibition is not the result of chemical transformations of these compounds to a single inhibitor, as well as it is not the result of NO release from these substances (as NO traps have no effect on the extent of inhibition). It was found that chloride and bromide in concentration above 80 mM and thiocyanate in concentration above 20 μM enhance catalase inhibition by nitrite and the nitroso compounds more than 100 times. The inhibition degree in this case is comparable with that induced by azide. We propose that the direct catalase inhibitor is a positively charged NO-group. This group acquires a positive charge in the active center of enzyme by interaction of nitrite or nitroso compounds with some enzyme groups. Halides and thiocyanate protect the NO+ group from hydration and thus increase its inhibition effect. It is probable that a comparatively low chloride concentration in many cells is the main factor to protect catalase from inhibition by nitrite and nitroso compounds.

  7. Extracellular localization of catalase is associated with the transformed state of malignant cells.

    Science.gov (United States)

    Böhm, Britta; Heinzelmann, Sonja; Motz, Manfred; Bauer, Georg

    2015-12-01

    Oncogenic transformation is dependent on activated membrane-associated NADPH oxidase (NOX). However, the resultant extracellular superoxide anions are also driving the NO/peroxynitrite and the HOCl pathway, which eliminates NOX-expressing transformed cells through selective apoptosis induction. Tumor progression is dependent on dominant interference with intercellular apoptosis-inducing ROS signaling through membrane-associated catalase, which decomposes H2O2 and peroxynitrite and oxidizes NO. Particularly, the decomposition of extracellular peroxynitrite strictly requires membrane-associated catalase. We utilized small interfering RNA (siRNA)-mediated knockdown of catalase and neutralizing antibodies directed against the enzyme in combination with challenging H2O2 or peroxynitrite to determine activity and localization of catalase in cells from three distinct steps of multistage oncogenesis. Nontransformed cells did not generate extracellular superoxide anions and only showed intracellular catalase activity. Transformed cells showed superoxide anion-dependent intercellular apoptosis-inducing ROS signaling in the presence of suboptimal catalase activity in their membrane. Tumor cells exhibited tight control of intercellular apoptosis-inducing ROS signaling through a high local concentration of membrane-associated catalase. These data demonstrate that translocation of catalase to the outside of the cell membrane is already associated with the transformation step. A strong local increase in the concentration of membrane-associated catalase is achieved during tumor progression and is controlled by tumor cell-derived H2O2 and by transglutaminase.

  8. Immobilization of catalase via adsorption into natural and modified ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-06-03

    Jun 3, 2009 ... In the present work, the immobilization of catalase into natural active carbon and active carbon modified by hydrochloric acid was carried out. In the experimental section, the effects of pH, ionic strength and reaction temperature were chosen as parameters, with experiments performed in batch system.

  9. Transposon-induced catalase-deficient Agrobacterium tumefaciens.

    Science.gov (United States)

    Khetmalas, M B

    1997-09-01

    Agrobacterium tumefaciens MKR, a nonpathogenic strain, has three catalase isozymes and one superoxide dismutase but no detectable peroxidase activity. A large number (8400) of transconjugants were obtained with pSUP1011::Tn5 suicide vector. The transposition frequencies were found to be greater in biparental mating than in triparental mating with helper plasmid. Mutants MLA31, MLA32, MLA41, and MLA41(a), generated by transposon mutagenesis, all lacked one of the catalase isozymes. Mutants were more susceptible to cell death than the wild type upon direct exposure to 10.0 mmol L-1 H2O2. The specific activity of the enzyme catalase was found to be higher in nitrogen-rich growth medium than carbon-rich growth medium.

  10. Ethnobotanical review and pharmacological properties of selected medicinal plants in Brunei Darussalam: Litsea elliptica, Dillenia suffruticosa, Dillenia excelsa, Aidia racemosa, Vitex pinnata and Senna alata

    National Research Council Canada - National Science Library

    Goh, May Poh Yik; Basri, Aida Maryam; Yasin, Hartini; Taha, Hussein; Ahmad, Norhayati

    2017-01-01

    The aim of the current study is to review the medicinal properties of the plants found in Brunei Darussalam namely Litsea elliptica, Dillenia suffruticosa, Dillenia excelsa, Aidia racemosa, Vitex pinnata and Senna alata...

  11. Temporal Effects of Catalase Overexpression on Healing Following Myocardial Infarction

    Science.gov (United States)

    Pendergrass, Karl D.; Varghese, Susan T.; Maiellaro-Rafferty, Kathryn; Brown, Milton E.; Taylor, W. Robert; Davis, Michael E.

    2011-01-01

    Background Reactive oxygen species, such as hydrogen peroxide (H2O2), contribute to progression of dysfunction following myocardial infarction (MI). However, chronic overexpression studies do not agree with acute protein delivery studies. The purpose of the present study was to assess the temporal role of cardiomyocyte-derived H2O2 scavenging on cardiac function after infarction using an inducible system. Methods and Results We developed a tamoxifen-inducible, cardiomyocyte-specific catalase overexpressing mouse. Catalase overexpression was induced either 5 days pre or post-MI. Mice exhibited a 3-fold increase in cardiac catalase activity that was associated with a significant decrease in H2O2 levels at both 7 and 21 days. However, cardiac function improved only at the later time point. Pro-inflammatory and fibrotic genes were acutely upregulated after MI, but catalase overexpression abolished the increase, despite no acute change in function. This led to reduced overall scar formation, with lower levels of Collagen 1A and increased contractile Collagen 3A expression at 21 days. Conclusions In contrast to prior studies, there were no acute functional improvements with physiological catalase overexpression prior to MI. Scavenging of H2O2 however, reduced pro-inflammatory cytokines and altered cardiac collagen isoforms, associated with an improvement in cardiac function after 21 days. Our results suggest that sustained H2O2 levels, rather than acute levels immediately following MI, may be critical in directing remodeling and cardiac function at later time points. PMID:20971939

  12. Embryonic catalase protects against ethanol embryopathies in acatalasemic mice and transgenic human catalase-expressing mice in embryo culture

    Energy Technology Data Exchange (ETDEWEB)

    Miller-Pinsler, Lutfiya [Department of Pharmacology and Toxicology, Faculty of Medicine, University of Toronto, Toronto, Ontario (Canada); Wells, Peter G., E-mail: pg.wells@utoronto.ca [Division of Biomolecular Sciences, Faculty of Pharmacy, University of Toronto, Toronto, Ontario (Canada); Department of Pharmacology and Toxicology, Faculty of Medicine, University of Toronto, Toronto, Ontario (Canada)

    2015-09-15

    Reactive oxygen species (ROS) have been implicated in the mechanism of ethanol (EtOH) teratogenicity, but the protective role of the embryonic antioxidative enzyme catalase is unclear, as embryonic activity is only about 5% of maternal levels. We addressed this question in a whole embryo culture model. C57BL/6 mouse embryos expressing human catalase (hCat) or their wild-type (C57BL/6 WT) controls, and C3Ga.Cg-Cat{sup b}/J catalase-deficient, acatalasemic (aCat) mouse embryos or their wild-type C3HeB/FeJ (C3H WT) controls, were explanted on gestational day (GD) 9 (plug = GD 1), exposed for 24 h to 2 or 4 mg/mL EtOH or vehicle, and evaluated for functional and morphological changes. hCat and C57BL/6 WT vehicle-exposed embryos developed normally, while EtOH was embryopathic in C57BL/6 WT embryos, evidenced by decreases in anterior neuropore closure, somites developed, turning and head length, whereas hCat embryos were protected (p < 0.001). Maternal pretreatment of C57BL/6 WT dams with 50 kU/kg PEG-catalase (PEG-cat) 8 h prior to embryo culture, which increases embryonic catalase activity, blocked all EtOH embryopathies (p < 0.001). Vehicle-exposed aCat mouse embryos had lower yolk sac diameters compared to WT controls, suggesting that endogenous ROS are embryopathic. EtOH was more embryopathic in aCat embryos than WT controls, evidenced by reduced head length and somite development (p < 0.01), and trends for reduced anterior neuropore closure, turning and crown–rump length. Maternal pretreatment of aCat dams with PEG-Cat blocked all EtOH embryopathies (p < 0.05). These data suggest that embryonic catalase is a determinant of risk for EtOH embryopathies. - Highlights: • Ethanol (EtOH) exposure causes structural embryopathies in embryo culture. • Genetically enhanced catalase (hCat) protects against EtOH embryopathies. • Genetically deficient catalase (aCat) exacerbates EtOH embryopathies. • Embryonic catalase is developmentally important. • Et

  13. Overexpression of Catalase in Vascular Smooth Muscle Cells Prevents the Formation of Abdominal Aortic Aneurysms

    Science.gov (United States)

    Parastatidis, Ioannis; Weiss, Daiana; Joseph, Giji; Taylor, W Robert

    2013-01-01

    Objective Elevated levels of oxidative stress have been reported in abdominal aortic aneurysms (AAA), but which reactive oxygen species (ROS) promotes the development of AAA remains unclear. Here we investigate the effect of the hydrogen peroxide (H2O2) degrading enzyme catalase on the formation of AAA. Approach and Results AAA were induced with the application of calcium chloride (CaCl2) on mouse infrarenal aortas. The administration of PEG-catalase, but not saline, attenuated the loss of tunica media and protected against AAA formation (0.91±0.1 mm vs. 0.76±0.09 mm). Similarly, in a transgenic mouse model, catalase over-expression in the vascular smooth muscle cells (VSMC) preserved the thickness of tunica media and inhibited aortic dilatation by 50% (0.85±0.14 mm vs. 0.57±0.08 mm). Further studies showed that injury with CaCl2 decreased catalase expression and activity in the aortic wall. Pharmacologic administration or genetic over-expression of catalase restored catalase activity and subsequently decreased matrix metalloproteinase activity. In addition, a profound reduction in inflammatory markers and VSMC apoptosis was evident in aortas of catalase over-expressing mice. Interestingly, as opposed to infusion of PEG-catalase, chronic over-expression of catalase in VSMC did not alter the total aortic H2O2 levels. Conclusions The data suggest that a reduction in aortic wall catalase activity can predispose to AAA formation. Restoration of catalase activity in the vascular wall enhances aortic VSMC survival and prevents AAA formation primarily through modulation of matrix metalloproteinase activity. PMID:23950141

  14. Exogenous melatonin suppresses dark-induced leaf senescence by activating the superoxide dismutase-catalase antioxidant pathway and down-regulating chlorophyll degradation in excised leaves of perennial ryegrass (Lolium perenne L.

    Directory of Open Access Journals (Sweden)

    Jing Zhang

    2016-10-01

    Full Text Available Leaf senescence is a typical symptom in plants exposed to dark and may be regulated by plant growth regulators. The objective of this study was to determine whether exogenous application of melatonin (N-acetyl-5-methoxytryptamine suppresses dark-induced leaf senescence and the effects of melatonin on reactive oxygen species (ROS scavenging system and chlorophyll degradation pathway in perennial grass species. Mature perennial ryegrass (Lolium perenne L. cv. ‘Pinnacle’ leaves were excised and incubated in 3 mM 2-(N-morpholino ethanesulfonic buffer (pH 5.8 supplemented with melatonin or water (control and exposed to dark treatment for 8 d. Leaves treated with melatonin maintained significantly higher endogenous melatonin level, chlorophyll content, photochemical efficiency, and cell membrane stability expressed by lower electrolyte leakage and malondialdehyde (MDA content compared to the control. Exogenous melatonin treatment also reduced the transcript level of chlorophyll degradation-associated genes and senescence marker genes (LpSAG12.1, Lph36, and Lpl69 during the dark treatment. The endogenous O2- production rate and H2O2 content were significantly lower in these excised leaves treated with melatonin compared to the water control. Exogenous melatonin treatment caused increases in enzymatic activity and transcript levels of superoxide dismutase and catalase but had no significant effects on ascorbate peroxidase, glutathione reductase, dehydroascorbate reductase, and monohydroascorbate reductase. The content of non-enzymatic antioxidants, such as ascorbate and dehydroascorbate, were decreased by melatonin treatment, while the content of glutathione and oxidized glutathione was not affected by melatonin. These results suggest that the suppression of dark-induced leaf senescence by exogenous melatonin may be associated with its roles in regulating ROS scavenging through activating the superoxide dismutase-catalase enzymatic antioxidant

  15. Increase in Catalase mRNA in Wounded Sweet Potato Tuberous Root Tissue

    OpenAIRE

    Shigeru, Sakajo; Kenzo, Nakamura; Tadashi, Asahi; Laboratory of Biochemistry, Faculty of Agriculture, Nagoya University

    1987-01-01

    Catalase protein, as well as its activity, increases in wounded sweet potato tuberous root tissue [Esaka et al. (1983) Plant Cell Physiol. 24: 615]. Whether catalase mRNA increases in wounded tissue was examined with a hybridization probe of a cDNA for sweet potato catalase mRNA. The content of catalase mRNA in the tissue increased after a lag phase of 10 h to reach a maximum at 30 h after wounding, whereas total RNA content increased without a lag phase. The increase in the mRNA content afte...

  16. High Dietary Fat Selectively Increases Catalase Expression within Cardiac Mitochondria*

    Science.gov (United States)

    Rindler, Paul M.; Plafker, Scott M.; Szweda, Luke I.; Kinter, Michael

    2013-01-01

    Obesity is a predictor of diabetes and cardiovascular disease. One consequence of obesity is dyslipidemia characterized by high blood triglycerides. It has been proposed that oxidative stress, driven by utilization of lipids for energy, contributes to these diseases. The effects of oxidative stress are mitigated by an endogenous antioxidant enzyme network, but little is known about its response to high fat utilization. Our experiments used a multiplexed quantitative proteomics method to measure antioxidant enzyme expression in heart tissue in a mouse model of diet-induced obesity. This experiment showed a rapid and specific up-regulation of catalase protein, with subsequent assays showing increases in activity and mRNA. Catalase, traditionally considered a peroxisomal protein, was found to be present in cardiac mitochondria and significantly increased in content and activity during high fat feeding. These data, coupled with the fact that fatty acid oxidation enhances mitochondrial H2O2 production, suggest that a localized catalase increase is needed to consume excessive mitochondrial H2O2 produced by increased fat metabolism. To determine whether the catalase-specific response is a common feature of physiological conditions that increase blood triglycerides and fatty acid oxidation, we measured changes in antioxidant expression in fasted versus fed mice. Indeed, a similar specific catalase increase was observed in mice fasted for 24 h. Our findings suggest a fundamental metabolic process in which catalase expression is regulated to prevent damage while preserving an H2O2-mediated sensing of diet composition that appropriately adjusts insulin sensitivity in the short term as needed to prioritize lipid metabolism for complete utilization. PMID:23204527

  17. Characterization of partially purified catalase from camel (Camelus ...

    African Journals Online (AJOL)

    Prof.Dr. Saleh

    2012-05-17

    May 17, 2012 ... chromatography on diethylaminoethyl cellulose (DEAE)-Sepharose. One peak catalase activity was obtained from the ... rapid cleavage of hydrogen peroxide and small organic peroxides, but also by other cellular ... microbiologists to identify species of bacteria. (Brioukhanov et al., 2006). Although, there is ...

  18. Purification and characterization of an intracellular catalase-peroxidase from Penicillium simplicissimum

    NARCIS (Netherlands)

    Fraaije, Marco W.; Roubroeks, Hanno P.; Hagen, Wilfred R.; Berkel, Willem J.H. van

    1996-01-01

    The first dimeric catalase-peroxidase of eucaryotic origin, an intracellular hydroperoxidase from Penicillium simplicissimum which exhibited both catalase and peroxidase activities, has been isolated. The enzyme has an apparent molecular mass of about 170 kDa and is composed of two identical

  19. Cytoplasmic catalase and ghostlike peroxisomes in the liver from a child with atypical chondrodysplasia punctata

    NARCIS (Netherlands)

    Espeel, M.; Heikoop, J. C.; Smeitink, J. A.; Beemer, F. A.; de Craemer, D.; van den Berg, M.; Hashimoto, T.; Wanders, R. J.; Schutgens, R. B.; Poll-The, B. T.

    1993-01-01

    In the liver biopsy from an 8.5-year-old girl with the biochemical characteristics of rhizomelic chondrodysplasia punctata (RCDP), but with normal limbs, normal catalase-containing peroxisomes were absent. Light microscopy after diaminobenzidine staining for catalase activity (the peroxisomal marker

  20. Public perceptions of hazards associated with Brazil nuts (Bertholletia excelsa) : evaluation of risk within an European context

    OpenAIRE

    Carreira, S.; Cunha, L. M.; Moura, Ana Pinto de; Lima, R. C.; Souza, M. P.; Souza Filho, T. A.; Silva, T. N.; Pedrozo, E. A.

    2015-01-01

    One of the most important economic plants of the Amazon is the Brazil nut (Bertholletia excelsa). Brazil nuts for international trade are mainly obtained from wild collection rather than from plantations, often cited as one of the most important products of extractive reserves in Amazonia. The European Commission (2003/493/EC) has imposed strict regulations on the import from Brazil of Brazil nuts in their shells, as the shells have been found to contain high levels of aflatoxi...

  1. Biochemical effects of glyphosate based herbicide, Excel Mera 71 on enzyme activities of acetylcholinesterase (AChE), lipid peroxidation (LPO), catalase (CAT), glutathione-S-transferase (GST) and protein content on teleostean fishes.

    Science.gov (United States)

    Samanta, Palas; Pal, Sandipan; Mukherjee, Aloke Kumar; Ghosh, Apurba Ratan

    2014-09-01

    Effects of glyphosate based herbicide, Excel Mera 71 at a dose of 17.20mg/l on enzyme activities of acetylcholinesterase (AChE), lipid peroxidation (LPO), catalase (CAT), glutathione-S-transferase (GST) and protein content were measured in different tissues of two Indian air-breathing teleosts, Anabas testudineus (Bloch) and Heteropneustes fossilis (Bloch) during an exposure period of 30 days under laboratory condition. AChE activity was significantly increased in all the investigated tissues of both fish species and maximum elevation was observed in brain of H. fossilis, while spinal cord of A. testudineus showed minimum increment. Fishes showed significant increase LPO levels in all the tissues; highest was observed in gill of A. testudineus but lowest LPO level was observed in muscle of H. fossilis. CAT was also enhanced in both the fishes, while GST activity in liver diminished substantially and minimum was observed in liver of A. testudineus. Total protein content showed decreased value in all the tissues, maximum reduction was observed in liver and minimum in brain of A. testudineus and H. fossilis respectively. The results indicated that Excel Mera 71 caused serious alterations in the enzyme activities resulting into severe deterioration of fish health; so, AChE, LPO, CAT and GST can be used as suitable indicators of herbicidal toxicity. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. Effects of peroxisomal catalase inhibition on mitochondrial function.

    Directory of Open Access Journals (Sweden)

    Paul eWalton

    2012-04-01

    Full Text Available Peroxisomes produce hydrogen peroxide as a metabolic by-product of their many oxidase enzymes, but contain catalase that breaks down hydrogen peroxide in order to maintain the organelle’s oxidative balance. It has been previously demonstrated that, as cells age, catalase is increasingly absent from the peroxisome, and resides instead as an unimported tetrameric molecule in the cell cytosol; an alteration that is coincident with increased cellular hydrogen peroxide levels. As this process begins in middle-passage cells, we sought to determine whether peroxisomal hydrogen peroxide could contribute to the oxidative damage observed in mitochondria in late-passage cells. Early-passage human fibroblasts (Hs27 treated with aminotriazole (3-AT, an irreversible catalase inhibitor, demonstrated decreased catalase activity, increased levels of cellular hydrogen peroxide, protein carbonyls, and peroxisomal numbers. This treatment increased mitochondrial ROS levels, and decreased the mitochondrial aconitase activity by approximately 85% within 24 hours. In addition, mitochondria from 3-AT treated cells show a decrease in inner membrane potential. These results demonstrate that peroxisome-derived oxidative imbalance may rapidly impair mitochondrial function, and considering that peroxisomal oxidative imbalance begins to occur in middle-passage cells, supports the hypothesis that peroxisomal oxidant release occurs upstream of, and contributes to, the mitochondrial damage observed in aging cells.

  3. Inhibition of catalase by tea catechins in free and cellular state: a biophysical approach.

    Directory of Open Access Journals (Sweden)

    Sandip Pal

    Full Text Available Tea flavonoids bind to variety of enzymes and inhibit their activities. In the present study, binding and inhibition of catalase activity by catechins with respect to their structure-affinity relationship has been elucidated. Fluorimetrically determined binding constants for (--epigallocatechin gallate (EGCG and (--epicatechin gallate (ECG with catalase were observed to be 2.27×106 M(-1 and 1.66×106 M(-1, respectively. Thermodynamic parameters evidence exothermic and spontaneous interaction between catechins and catalase. Major forces of interaction are suggested to be through hydrogen bonding along with electrostatic contributions and conformational changes. Distinct loss of α-helical structure of catalase by interaction with EGCG was captured in circular dichroism (CD spectra. Gallated catechins demonstrated higher binding constants and inhibition efficacy than non-gallated catechins. EGCG exhibited maximum inhibition of pure catalase. It also inhibited cellular catalase in K562 cancer cells with significant increase in cellular ROS and suppression of cell viability (IC50 54.5 µM. These results decipher the molecular mechanism by which tea catechins interact with catalase and highlight the potential of gallated catechin like EGCG as an anticancer drug. EGCG may have other non-specific targets in the cell, but its anticancer property is mainly defined by ROS accumulation due to catalase inhibition.

  4. Inhibition of catalase by tea catechins in free and cellular state: a biophysical approach.

    Science.gov (United States)

    Pal, Sandip; Dey, Subrata Kumar; Saha, Chabita

    2014-01-01

    Tea flavonoids bind to variety of enzymes and inhibit their activities. In the present study, binding and inhibition of catalase activity by catechins with respect to their structure-affinity relationship has been elucidated. Fluorimetrically determined binding constants for (-)-epigallocatechin gallate (EGCG) and (-)-epicatechin gallate (ECG) with catalase were observed to be 2.27×106 M(-1) and 1.66×106 M(-1), respectively. Thermodynamic parameters evidence exothermic and spontaneous interaction between catechins and catalase. Major forces of interaction are suggested to be through hydrogen bonding along with electrostatic contributions and conformational changes. Distinct loss of α-helical structure of catalase by interaction with EGCG was captured in circular dichroism (CD) spectra. Gallated catechins demonstrated higher binding constants and inhibition efficacy than non-gallated catechins. EGCG exhibited maximum inhibition of pure catalase. It also inhibited cellular catalase in K562 cancer cells with significant increase in cellular ROS and suppression of cell viability (IC50 54.5 µM). These results decipher the molecular mechanism by which tea catechins interact with catalase and highlight the potential of gallated catechin like EGCG as an anticancer drug. EGCG may have other non-specific targets in the cell, but its anticancer property is mainly defined by ROS accumulation due to catalase inhibition.

  5. Inhibition of Catalase by Tea Catechins in Free and Cellular State: A Biophysical Approach

    Science.gov (United States)

    Pal, Sandip; Dey, Subrata Kumar; Saha, Chabita

    2014-01-01

    Tea flavonoids bind to variety of enzymes and inhibit their activities. In the present study, binding and inhibition of catalase activity by catechins with respect to their structure-affinity relationship has been elucidated. Fluorimetrically determined binding constants for (−)-epigallocatechin gallate (EGCG) and (−)-epicatechin gallate (ECG) with catalase were observed to be 2.27×106 M−1 and 1.66×106 M−1, respectively. Thermodynamic parameters evidence exothermic and spontaneous interaction between catechins and catalase. Major forces of interaction are suggested to be through hydrogen bonding along with electrostatic contributions and conformational changes. Distinct loss of α-helical structure of catalase by interaction with EGCG was captured in circular dichroism (CD) spectra. Gallated catechins demonstrated higher binding constants and inhibition efficacy than non-gallated catechins. EGCG exhibited maximum inhibition of pure catalase. It also inhibited cellular catalase in K562 cancer cells with significant increase in cellular ROS and suppression of cell viability (IC50 54.5 µM). These results decipher the molecular mechanism by which tea catechins interact with catalase and highlight the potential of gallated catechin like EGCG as an anticancer drug. EGCG may have other non-specific targets in the cell, but its anticancer property is mainly defined by ROS accumulation due to catalase inhibition. PMID:25025898

  6. Covalent Immobilization of Catalase onto Regenerated Silk Fibroins via Tyrosinase-Catalyzed Cross-Linking.

    Science.gov (United States)

    Wang, Ping; Qi, Chenglong; Yu, Yuanyuan; Yuan, Jiugang; Cui, Li; Tang, Gengtie; Wang, Qiang; Fan, Xuerong

    2015-09-01

    Regenerated silk fibroins could be used as medical scaffolds and carrier materials for enzyme immobilization. In the present work, tyrosinase enzyme was used for enzymatic oxidation of silk fibroins, followed by immobilization of catalase onto the fibroin surfaces through physical adsorption and covalent cross-linking as well. Spectrophotometry, SDS-PAGE, and Fourier transform infrared spectroscopy (FTIR) were used to examine the efficiency of enzymatic oxidation and catalase immobilization, respectively. The results indicate that tyrosine residues in silk fibroins could be oxidized and converted to the active o-quinones. Incubating silk fibroins with catalase and tyrosinase led to a noticeable change of molecular weight distribution, indicating the occurrence of the cross-links between silk fibroins and catalase molecules. Two different pathways were proposed for the catalase immobilizations, and the method based on grafting of catalase onto the freeze-dried fibroin membrane is more acceptable. The residual enzyme activity for the immobilized catalase exhibited higher than that of the control after repeated washing cycles. Meanwhile, the thermal stability and alkali resistance were also slightly improved as compared to free catalase. The mechanisms of enzymatic immobilization are also concerned.

  7. Embryonic catalase protects against ethanol embryopathies in acatalasemic mice and transgenic human catalase-expressing mice in embryo culture.

    Science.gov (United States)

    Miller-Pinsler, Lutfiya; Wells, Peter G

    2015-09-15

    Reactive oxygen species (ROS) have been implicated in the mechanism of ethanol (EtOH) teratogenicity, but the protective role of the embryonic antioxidative enzyme catalase is unclear, as embryonic activity is only about 5% of maternal levels. We addressed this question in a whole embryo culture model. C57BL/6 mouse embryos expressing human catalase (hCat) or their wild-type (C57BL/6 WT) controls, and C3Ga.Cg-Cat(b)/J catalase-deficient, acatalasemic (aCat) mouse embryos or their wild-type C3HeB/FeJ (C3H WT) controls, were explanted on gestational day (GD) 9 (plug=GD 1), exposed for 24h to 2 or 4mg/mL EtOH or vehicle, and evaluated for functional and morphological changes. hCat and C57BL/6 WT vehicle-exposed embryos developed normally, while EtOH was embryopathic in C57BL/6 WT embryos, evidenced by decreases in anterior neuropore closure, somites developed, turning and head length, whereas hCat embryos were protected (pcatalase (PEG-cat) 8h prior to embryo culture, which increases embryonic catalase activity, blocked all EtOH embryopathies (pcatalase is a determinant of risk for EtOH embryopathies. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Catalase inhibits ionizing radiation-induced apoptosis in hematopoietic stem and progenitor cells.

    Science.gov (United States)

    Xiao, Xia; Luo, Hongmei; Vanek, Kenneth N; LaRue, Amanda C; Schulte, Bradley A; Wang, Gavin Y

    2015-06-01

    Hematologic toxicity is a major cause of mortality in radiation emergency scenarios and a primary side effect concern in patients undergoing chemo-radiotherapy. Therefore, there is a critical need for the development of novel and more effective approaches to manage this side effect. Catalase is a potent antioxidant enzyme that coverts hydrogen peroxide into hydrogen and water. In this study, we evaluated the efficacy of catalase as a protectant against ionizing radiation (IR)-induced toxicity in hematopoietic stem and progenitor cells (HSPCs). The results revealed that catalase treatment markedly inhibits IR-induced apoptosis in murine hematopoietic stem cells and hematopoietic progenitor cells. Subsequent colony-forming cell and cobble-stone area-forming cell assays showed that catalase-treated HSPCs can not only survive irradiation-induced apoptosis but also have higher clonogenic capacity, compared with vehicle-treated cells. Moreover, transplantation of catalase-treated irradiated HSPCs results in high levels of multi-lineage and long-term engraftments, whereas vehicle-treated irradiated HSPCs exhibit very limited hematopoiesis reconstituting capacity. Mechanistically, catalase treatment attenuates IR-induced DNA double-strand breaks and inhibits reactive oxygen species. Unexpectedly, we found that the radioprotective effect of catalase is associated with activation of the signal transducer and activator of transcription 3 (STAT3) signaling pathway and pharmacological inhibition of STAT3 abolishes the protective activity of catalase, suggesting that catalase may protect HSPCs against IR-induced toxicity via promoting STAT3 activation. Collectively, these results demonstrate a previously unrecognized mechanism by which catalase inhibits IR-induced DNA damage and apoptosis in HSPCs.

  9. Influence of nutritive substrate and pH on catalase and peroxidase production in saprophytic fungus Rhizopus nigricans

    National Research Council Canada - National Science Library

    Tamara Barbaneagra; Mihaela Cristica; Elena Ciornea; Alexandru Manoliu

    2012-01-01

    .... The purpose of this paper is to determine the antioxidant response in fungus Rhizopus nigricans, materialized trough enzymatic activity of biochemical markers of oxidative stress - catalase and peroxidase...

  10. Enhancement of superoxide dismutase and catalase activity in juvenile brown shrimp, Farfantepenaeus californiensis (Holmes, 1900, fed β-1.3 glucan vitamin E, and β-carotene and infected with white spot syndrome virus

    Directory of Open Access Journals (Sweden)

    Rosario Pacheco

    2011-11-01

    Full Text Available The effect of dietary β-Ο-glucan, vitamin E, and β-carotene supplements in juvenile brown shrimp, Farfantepenaeus californiensis, inoculated with white spot syndrome virus (WSSV was evaluated. Groups of 30 organisms (weighing 1 ± 0.5 g were cultured in 60 L fiberglass tanks and fed daily with β-1.3-glucan (0.1%, vitamin E (0.01%, and β-carotene (0.01% for 23 days; the specimens were then inoculated with WSSV. The antioxidant activity of the enzymes superoxide dismutase (SOD and catalase (CAT were determined in the hepatopancreas and muscle at 0, 1, 6, 12, 24, and 48 h after inoculation. Shrimp fed with β-1.3-glucan, vitamin E, and β-carotene significantly increased SOD activity in the hepatopancreas and muscle at 12 and 24 h post-infection, respectively. Shrimp fed with vitamin E and β-1.3-glucan registered an increment in SOD activity from 12 to 48 h post-infection. Shrimp fed with β-carotene increased SOD activity before infection with WSSV, and shrimp fed with β-1.3-glucan and vitamin E increased CAT activity, also before infection. The CAT activity response in shrimp muscle increased with respect to the control group for all treatments tested from 1 to 6 h after inoculation with WSSV. The highest antioxidant response was registered in shrimp fed with vitamin E. Juvenile shrimp fed with vitamin E and later inoculated with WSSV registered 100% mortality at 72 h, but shrimp fed with β-Ο-glucan and β-carotene showed greater resistance to WSSV, with mortality at 144 h post-infection. This study demonstrated the capacity of juvenile Farfantepenaeus californiensis fed β-Ο-glucan, vitamin E, or β-carotene to increase the antioxidant response before and after viral infection.

  11. Soluble epoxide hydrolase contamination of specific catalase preparations inhibits epoxyeicosatrienoic acid vasodilation of rat renal arterioles

    Science.gov (United States)

    Olson, Lauren; Harder, Adam; Isbell, Marilyn; Imig, John D.; Gutterman, David D.; Falck, J. R.; Campbell, William B.

    2011-01-01

    Cytochrome P-450 metabolites of arachidonic acid, the epoxyeicosatrienoic acids (EETs) and hydrogen peroxide (H2O2), are important signaling molecules in the kidney. In renal arteries, EETs cause vasodilation whereas H2O2 causes vasoconstriction. To determine the physiological contribution of H2O2, catalase is used to inactivate H2O2. However, the consequence of catalase action on EET vascular activity has not been determined. In rat renal afferent arterioles, 14,15-EET caused concentration-related dilations that were inhibited by Sigma bovine liver (SBL) catalase (1,000 U/ml) but not Calbiochem bovine liver (CBL) catalase (1,000 U/ml). SBL catalase inhibition was reversed by the soluble epoxide hydrolase (sEH) inhibitor tAUCB (1 μM). In 14,15-EET incubations, SBL catalase caused a concentration-related increase in a polar metabolite. Using mass spectrometry, the metabolite was identified as 14,15-dihydroxyeicosatrienoic acid (14,15-DHET), the inactive sEH metabolite. 14,15-EET hydrolysis was not altered by the catalase inhibitor 3-amino-1,2,4-triazole (3-ATZ; 10–50 mM), but was abolished by the sEH inhibitor BIRD-0826 (1–10 μM). SBL catalase EET hydrolysis showed a regioisomer preference with greatest hydrolysis of 14,15-EET followed by 11,12-, 8,9- and 5,6-EET (Vmax = 0.54 ± 0.07, 0.23 ± 0.06, 0.18 ± 0.01 and 0.08 ± 0.02 ng DHET·U catalase−1·min−1, respectively). Of five different catalase preparations assayed, EET hydrolysis was observed with two Sigma liver catalases. These preparations had low specific catalase activity and positive sEH expression. Mass spectrometric analysis of the SBL catalase identified peptide fragments matching bovine sEH. Collectively, these data indicate that catalase does not affect EET-mediated dilation of renal arterioles. However, some commercial catalase preparations are contaminated with sEH, and these contaminated preparations diminish the biological activity of H2O2 and EETs. PMID:21753077

  12. BIOMASSA, CRESCIMENTO E RESPOSTAS ECOFISIOLÓGICAS DE PLANTAS JOVENS DE Bertholletia excelsa BONPL. SUBMETIDAS A DIFERENTES NÍVEIS DE IRRADIÂNCIA

    Directory of Open Access Journals (Sweden)

    Cristiane Santos do Carmo Ribeiro de Souza

    2017-01-01

    Full Text Available Brazil nut ( Bertholletia excelsa Bonpl. is a light-demanding species, because in natural forest, the species depending of formation of clearings for reach reproduction size and in forest plantation, showing fast initial growth when exposed to high levels of irradiance. However, the ecophysiological traits of this species under contrasting conditions of irradiance were not investigated. In this study, in addition to growth traits, we investigated for first time the degree of plasticity of ecophysiological response of Bertholletia excelsa when subjected to contrasting irradiance environments. Young plants of Bertholletia excelsa were cultivated under three conditions of irradiance: low (20-300 μmol m -2 s -1 , moderate (800-1000 μmol m -2 s -1 and high (1900-2100 μmol m -2 s -1 . We analyzed the growth traits, gas exchange, chloroplastid pigment contents and, the end of experiment, the accumulation and partitioning of biomass. Young plants of Bertholletia excelsa showed the highest values of biomass, growth and photosynthesis when exposed to environments of moderate and high irradiance. Low irradiance condition stimulated more biomass partitioning for shoot and chloroplastid pigment contents. Bertholletia excelsa showed physiological plasticity under contrasting conditions of irradiance, the largest growth and biomass accumulation in environments of moderate and high irradiance were promoted by better photosynthetic performance, whereas the positive carbon balance under low irradiance is ensured by investment in structures of interception and energy harvesting.

  13. Brazil Nut (Bertholletia excelsa, Lecythidaceae Regeneration in Logging Gaps in the Peruvian Amazon

    Directory of Open Access Journals (Sweden)

    Julian Moll-Rocek

    2014-01-01

    Full Text Available Brazil nut (Bertholletia excelsa Bonpl. extraction serves as an important economic resource in the Madre de Dios region of Peru simultaneously promoting forest conservation, yet, under current management, it cannot compete with other land uses. This study investigated the effects of logging gaps on Brazil nut natural regeneration. A total of 48 paired logging gap-understory sites were visited in Brazil nut concessions in the Tambopata province of Madre de Dios, Peru. At each site, the number of Brazil nut recruits was counted and canopy openness and gap area were measured. Significantly higher levels of recruit density were found in logging gaps than in understory sites. Additionally, recruit density was positively correlated with canopy openness. Further, in experimental plantings in paired gap and understory sites, canopy openness, height, total leaf area, and number were recorded from August 2011 to February 2012. Height, total leaf area, and leaf number were significantly higher for tree-fall gap grown seedlings, lending further evidence to improved recruitment success of Brazil nuts in forest gaps. These results suggest that multiple-use forest management could be considered as an alternative for the sustainable extraction of Brazil nuts but also highlight that further studies are required.

  14. Water uptake, priming, drying and storage effects inCassia excelsa Schrad seeds

    Directory of Open Access Journals (Sweden)

    Jeller H.

    2003-01-01

    Full Text Available The aims of this study were to evaluate the effects of osmotic potential on the water uptake curvein Cassia excelsa seeds and use the results to analyze the effects of dehydration and storage on primed seed germination. Seeds were imbibed in distillad water and polyethylene glicol (PEG 6000 osmotic solutions at -0.2, -0.4, and -0.6 MPa, at 20ºC. The radicle emergence and seed moisture content were evaluated at 6-hour intervals during 240 hours. Afterwards, seeds were primed in distillad water and PEG 6000 solutions at -0.2, -0.4, and -0.6 MPa for 48, 72, 96, and 168 hours at 20ºC, followed by air drying and storage for 15 days at 5ºC. The lower the osmotic potential, the higher the time required for priming. The osmoconditioning yields benefits with PEG solutions at 0.0 and -0.2 MPa; seed improvements were maintained during storage for 15 days at 5ºC, but were reverted by seed drying.

  15. Insight into the role of catalases in salt stress in potato (Solanum tuberosum L.).

    OpenAIRE

    M'Hamdi M.; Bettaieb T.; Harbaoui Y.; Mougou AA.; du Jardin P.

    2009-01-01

    In order to investigate a possible link between catalase (CAT) activity and salinity tolerance, an in vitro and in vivo study of the behavior of transgenic lines of potato (cv. ‘Désirée’) under salt stress conditions was carried out. Three groups of transgenic lines and non transformed control (DWT) were used in this study: lines expressing a bacterial catalase gene and lines repressing catalase activity by either co-suppression or anti-sense strategies. Various concentrations of NaCl were te...

  16. Occurrence of High Catalase-containing Acinetobacter in Spacecraft Assembly Facilities

    Science.gov (United States)

    McCoy, K. B.; Derecho, I.; La Duc, M. T.; Vaishampayan, P.; Venkateswaran, K. J.; Mogul, R.

    2010-04-01

    In summary, the measurement of high catalase specific activity values for spacecraft-associated Acinetobacter strains is potentially the result of adaptation towards the harsh conditions of the clean rooms and assembly process.

  17. The catalase reaction of Shigella species and its use in rapid screening for epidemic Shigella dysenteriae type 1.

    Science.gov (United States)

    Karas, J A; Pillay, D G; Sturm, A W

    2007-01-01

    As epidemic dysentery caused by Shigella dysenteriae type 1 is associated with high mortality, early identification of outbreaks is important. Since S. dysenteriae type 1 differs from most of the Enterobacteriaceae in that it does not produce catalase, a test for catalase may provide a useful screening method. The ability of a catalase test to provide rapid identification of S. dysenteriae type 1 has now been assessed, using isolates of this pathogen from five continents, Shigella of other species, and entero-invasive (EIEC) and Shiga-toxin-producing Escherichia coli (STEC). All of the isolates of S. dysenteriae type 1, as well as S. dysenteriae of types 3, 4, 6, 9, 11 and 12 and S. boydii of type 12, were found catalase-negative. All the other bacteria tested were positive for catalase. In an epidemic setting in South Africa, 406 xylose-negative and lysine-decarboxylase-negative isolates, collected from xylose-lysine-deoxycholate (XLD) agar, were tested for catalase. All 356 of the catalase-negative isolates were confirmed to be of S. dysenteriae type 1. None of the catalase-positive isolates were of S. dysenteriae type 1. The catalase test is useful in the rapid, presumptive identification of S. dysenteriae type 1, from appropriate culture media, because of its high predictive value, simplicity and speed. It would be particularly useful during dysentery outbreaks, when other Shigella would be uncommon. There was no association between the absence of catalase activity and the production of Shiga toxin.

  18. Expression of a bacterial catalase in a strictly anaerobic methanogen significantly increases tolerance to hydrogen peroxide but not oxygen

    Science.gov (United States)

    Jennings, Matthew E.; Schaff, Cody W.; Horne, Alexandra J.; Lessner, Faith H.

    2014-01-01

    Haem-dependent catalase is an antioxidant enzyme that degrades H2O2, producing H2O and O2, and is common in aerobes. Catalase is present in some strictly anaerobic methane-producing archaea (methanogens), but the importance of catalase to the antioxidant system of methanogens is poorly understood. We report here that a survey of the sequenced genomes of methanogens revealed that the majority of species lack genes encoding catalase. Moreover, Methanosarcina acetivorans is a methanogen capable of synthesizing haem and encodes haem-dependent catalase in its genome; yet, Methanosarcina acetivorans cells lack detectable catalase activity. However, inducible expression of the haem-dependent catalase from Escherichia coli (EcKatG) in the chromosome of Methanosarcina acetivorans resulted in a 100-fold increase in the endogenous catalase activity compared with uninduced cells. The increased catalase activity conferred a 10-fold increase in the resistance of EcKatG-induced cells to H2O2 compared with uninduced cells. The EcKatG-induced cells were also able to grow when exposed to levels of H2O2 that inhibited or killed uninduced cells. However, despite the significant increase in catalase activity, growth studies revealed that EcKatG-induced cells did not exhibit increased tolerance to O2 compared with uninduced cells. These results support the lack of catalase in the majority of methanogens, since methanogens are more likely to encounter O2 rather than high concentrations of H2O2 in the natural environment. Catalase appears to be a minor component of the antioxidant system in methanogens, even those that are aerotolerant, including Methanosarcina acetivorans. Importantly, the experimental approach used here demonstrated the feasibility of engineering beneficial traits, such as H2O2 tolerance, in methanogens. PMID:24222618

  19. O CUSTO SOCIAL DO DESMATAMENTO DA AMAZÔNIA BRASILEIRA: O CASO DA CASTANHA-DO-BRASIL (Bertholletia excelsa

    Directory of Open Access Journals (Sweden)

    Humberto Angelo

    2013-01-01

    Full Text Available In this article, it is studied the deforestation of ‘castanha-do-brasil’ (Bertholletia excelsa from the Brazilian tropical rainforest with emphasis on the valuation of social costs imposed on society by the reduction and the loss of forest cover from 1998 to 2008. To measure the social costs, the concept used was of Marshall economic surplus, which measures the level of welfare consumers and producers. From 1998 to 2008, the estimated average social costs were of R$ 11.6 million per year. The social costs falling 63 % on producers and 37 % on consumers. In conclusion, both, supply and demand, lose with damages in the Brazilian tropical rainforest.

  20. RESTORATION INDUCED BY CATALASE IN IRRADIATED MICROORGANISMS

    Science.gov (United States)

    Latarjet, Raymond; Caldas, Luis Renato

    1952-01-01

    1. E. coli, strain K-12, and B. megatherium 899, irradiated in strict but still undefined physiological conditions with certain heavy doses of ultraviolet light, are efficiently restored by catalase, which acts on or fixes itself upon the bacteria in a few minutes. This restoration (C. R.), different from photorestoration, is aided by a little visible light. 2. At 37° the restorability lasts for about 2 hours after UV irradiation; the restored cells begin to divide at the same time as the normal survivors. 3. C. R. is not produced after x-irradiation. 4. B. megatherium Mox and E. coli, strain B/r show little C. R.; E. coli strain B shows none. None of these three strains is lysogenic, whereas the two preceding catalase-restorable strains are. 5. Phage production in the system "K-12 infected with T2 phage" is restored by catalase after UV irradiation, whereas phage production in the system "infected B" is not. 6. With K-12, catalase does not prevent the growth of phage and the lysis induced by UV irradiation (Lwoff's phenomenon). 7. Hypotheses are discussed concerning: (a) the chemical nature of this action of catalase; (b) a possible relation between C. R. and lysogenicity of the sensitive bacteria; (c) the consequences of such chemical restorations on the general problem of cell radiosensitivity. PMID:14898028

  1. Simultaneous production of catalase, glucose oxidase and gluconic acid by Aspergillus niger mutant.

    Science.gov (United States)

    Fiedurek, J; Gromada, A; Pielecki, J

    1998-01-01

    The production of gluconic acid, extracellular glucose oxidase and catalase in submerged culture by a number of biochemical mutants has been evaluated. Optimization of stirrer speed, time cultivation and buffering action of some chemicals on glucose oxidase, catalase and gluconic acid production by the most active mutant, AM-11, grown in a 3-L glass bioreactor was investigated. Three hundred rpm appeared to be optimum to ensure good growth and best glucose oxidase production, but gluconic acid or catalase activity obtained maximal value at 500 or 900 rpm, respectively. Significant increase of dissolved oxygen concentration in culture (16-21%) and extracellular catalase activity were obtained when the traditional aeration was employed together with automatic dosed hydrogen peroxide.

  2. Isolation, Fractionation and Characterization of Catalase from Neurospora crassa (InaCC F226)

    Science.gov (United States)

    Suryani; Ambarsari, L.; Lindawati, E.

    2017-03-01

    Catalase from Indigenous isolate Neurospora crassa InaCC F226 has been isolated, fractionated and characterized. Production of catalase by Neurospora crassa was done by using PDA medium (Potato Dextrosa Agar) and fractionated with ammonium sulphate with 20-80% saturation. Fraction 60% was optimum saturation of ammonium sulphate and had highest specific activity 3339.82 U/mg with purity 6.09 times, total protein 0.920 mg and yield 88.57%. The optimum pH and temperature for catalase activity were at 40°C and pH 7.0, respectively. The metal ions that stimulated catalase activity acted were Ca2+, Mn2+ and Zn2+, and inhibitors were EDTA, Mg2+ and Cu2+. Based on Km and Vmax values were 0.2384 mM and 13.3156 s/mM.

  3. Targeted intracellular catalase delivery protects neonatal rat myocytes from hypoxia-reoxygenation and ischemia-reperfusion injury

    Science.gov (United States)

    Undyala, Vishnu; Terlecky, Stanley R.; Vander Heide, Richard S.

    2010-01-01

    Hypoxia followed by reoxygenation (HR) and ischemia-reperfusion (IR) cause cell death in neonatal rat ventricular myocytes (NRVM) primarily through the generation of oxidative stress. Extracellular catalase (CAT) has not been effective in reducing or eliminating IR or HR-induced cell death due both to extracellular degradation and poor cellular uptake. Aims 1) to determine if a cell penetrating catalase derivative with enhanced peroxisome targeting efficiency (catalase-SKL) increases intracellular levels of the antioxidant enzyme in NVRM; and 2) to determine if catalase-SKL protects against both HR and IR injury. Methods NRVM were subjected to 3 or 6 hr of HR or 1 hr of IR. CAT concentration, activity, and subcellular distribution were determined using standard techniques. Reactive oxygen species (ROS) and related oxidative stress were visualized using 2’,7’-dichlorofluorescin diacetate. Cell death was measured using trypan blue exclusion or lactate dehydrogenase (LDH) release assays. Results CAT activity was higher in (catalase-SKL) transduced myocytes, was concentrated in a membranous cellular fraction, and potently inhibited oxidative stress. In contrast to non-transducible (unmodified) CAT, catalase-SKL-treated myocytes were protected against both HR and IR. Conclusions 1) catalase-SKL increased myocyte CAT content and activity and dramatically increased resistance to hydrogen peroxide-induced oxidation; 2) catalase-SKL protects against both HR and IR; 3) catalase-SKL may represent a new therapeutic approach to protect hearts against myocardial HR or IR. PMID:20708413

  4. Estudo em raiz e ráquis foliar de spathelia excelsa: fitoquímica e atividade frente ao fungo Moniliophthora perniciosa associado ao cupuaçuzeiro (Theobroma grandiflorum

    Directory of Open Access Journals (Sweden)

    Loretta Ennes de Carvalho

    2012-01-01

    Full Text Available The chemical composition of Spathelia excelsa (Krause R. S. Cowan & Brizicky was investigated and the limonoids harrisonin (1 and deacetylspathelin (2, alkaloids folinin and casimiroin mixture (3a, b, plus a further casimiroin (3b were identified in methanol extract from root. The CH2Cl2 extract from the rachis yielded protolimonoid 3β-angeloyl-21,24-epoxy-7α,21α,23α,25-tetrahydroxy-4α,4β,8β,10β-tetramethyl-25-dimethyl-14,18-cyclo-5α,13α,14α,17α-cholestane (4, and methanol extract, the limonoids limonin diosphenol (5 and perforatin (6, as well as the chromone biflorin (7. Harrisonin and biflorin were isolated for the first time in this genus. On the antifungal assay against witches' broom (Moniliophthoraperniciosa compound 3b was found to be active.

  5. Effects of pergolide mesylate on transduction efficiency of PEP-1-catalase protein

    Energy Technology Data Exchange (ETDEWEB)

    Sohn, Eun Jeong; Kim, Dae Won; Kim, Young Nam; Kim, So Mi [Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chunchon 200-702 (Korea, Republic of); Lim, Soon Sung [Department of Food Science and Nutrition and RIC Center, Hallym University, Chunchon 200-702 (Korea, Republic of); Kang, Tae-Cheon [Department of Anatomy and Neurobiology, College of Medicine, Hallym University, Chunchon 200-702 (Korea, Republic of); Kwon, Hyeok Yil [Department of Physiology, College of Medicine, Hallym University, Chunchon 200-702 (Korea, Republic of); Kim, Duk-Soo [Department of Anatomy, College of Medicine, Soonchunhyang University, Cheonan-Si 330-090 (Korea, Republic of); Cho, Sung-Woo [Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine, Seoul 138-736 (Korea, Republic of); Han, Kyu Hyung; Park, Jinseu; Eum, Won Sik [Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chunchon 200-702 (Korea, Republic of); Hwang, Hyun Sook, E-mail: wazzup@hallym.ac.kr [Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chunchon 200-702 (Korea, Republic of); Choi, Soo Young, E-mail: sychoi@hallym.ac.kr [Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chunchon 200-702 (Korea, Republic of)

    2011-03-18

    Research highlights: {yields} We studied effects of pergolide mesylate (PM) on in vitro and in vivo transduction of PEP-1-catalase. {yields} PEP-1-catatase inhibited 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammation. {yields} PM enhanced the transduction of PEP-1-catalase into HaCaT cells and skin tissue. {yields} PM increased anti-inflammatory activity of PEP-1-catalase. {yields} PM stimulated therapeutic action of anti-oxidant enzyme catalase in oxidative-related diseases. -- Abstract: The low transduction efficiency of various proteins is an obstacle to their therapeutic application. However, protein transduction domains (PTDs) are well-known for a highly effective tool for exogenous protein delivery to cells. We examined the effects of pergolide mesylate (PM) on the transduction of PEP-1-catalase into HaCaT human keratinocytes and mice skin and on the anti-inflammatory activity of PEP-1-catatase against 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammation using Western blot and histological analysis. PM enhanced the time- and dose-dependent transduction of PEP-1-catalase into HaCaT cells without affecting the cellular toxicity. In a mouse edema model, PEP-1-catalase inhibited the increased expressions of inflammatory mediators and cytokines such as cyclooxygenase-2, inducible nitric oxide synthase, interleukin-6 and -1{beta}, and tumor necrosis factor-{alpha} induced by TPA. On the other hand, PM alone failed to exert any significant anti-inflammatory effects. However, the anti-inflammatory effect of co-treatment with PEP-1-catalase and PM was more potent than that of PEP-1-catalase alone. Our results indicate that PM may enhance the delivery of PTDs fusion therapeutic proteins to target cells and tissues and has potential to increase their therapeutic effects of such drugs against various diseases.

  6. Do pH and flavonoids influence hypochlorous acid-induced catalase inhibition and heme modification?

    Science.gov (United States)

    Krych-Madej, Justyna; Gebicka, Lidia

    2015-09-01

    Hypochlorous acid (HOCl), highly reactive oxidizing and chlorinating species, is formed in the immune response to invading pathogens by the reaction of hydrogen peroxide with chloride catalyzed by the enzyme myeloperoxidase. Catalase, an important antioxidant enzyme, catalyzing decomposition of hydrogen peroxide to water and molecular oxygen, hampers in vitro HOCl formation, but is also one of the main targets for HOCl. In this work we have investigated HOCl-induced catalase inhibition at different pH, and the influence of flavonoids (catechin, epigallocatechin gallate and quercetin) on this process. It has been shown that HOCl-induced catalase inhibition is independent on pH in the range 6.0-7.4. Preincubation of catalase with epigallocatechin gallate and quercetin before HOCl treatment enhances the degree of catalase inhibition, whereas catechin does not affect this process. Our rapid kinetic measurements of absorption changes around the heme group have revealed that heme modification by HOCl is mainly due to secondary, intramolecular processes. The presence of flavonoids, which reduce active catalase intermediate, Compound I to inactive Compound II have not influenced the kinetics of HOCl-induced heme modification. Possible mechanisms of the reaction of hypochlorous acid with catalase are proposed and the biological consequences are discussed. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Effect of Essential Unsaturated Fatty Acids on Structure and Function of Catalase at High Glucose Concentration

    Directory of Open Access Journals (Sweden)

    Hossain Mirmiranpoor

    2017-08-01

    Full Text Available Background: Assessment of changes in structure and activity of catalase, as an antioxidant enzymatic protein, in combination with glucose and essential unsaturated fatty acids is the aim of present study. Materials and Methods: In order to investigate the activity and structure of catalase, a solution of this enzyme with 10 mg/mL concentration in phosphate buffer (0.1 M and pH = 7.4, in the presence and absence of 50 mmol glucose was prepared, filtered, and then incubated for 4 months at 37°C with and without fatty acids including linolenic, linoleic, and arachidonic acids, separately. Samples were taken from each tube of solution, every 14 days for 4 months, to assess the fluorescence emission, circular dichroism (CD and activity. Results: According to the results, catalase showed increase in fluorescence emission and decrease in activity after incubation with glucose in comparison with pure protein. Moreover, catalase showed alteration in CD after incubation with glucose during 4 months. After incubation with glucose and each of the mentioned unsaturated fatty acids, alterations of catalase were neared toward normal level in fluorescence emission, CD, and activity in comparison with pure protein. Conclusion: Functional and structural protection of catalase against damages from hyperglycemic environment with addition of essential unsaturated fatty acids was proved in our investigation.

  8. Destructive effect of non-enzymatic glycation on catalase and remediation via curcumin.

    Science.gov (United States)

    Mofidi Najjar, Fayezeh; Taghavi, Fereshteh; Ghadari, Rahim; Sheibani, Nader; Moosavi-Movahedi, Ali Akbar

    2017-09-15

    Non-enzymatic glycation of proteins is a post-translational modification that is produced by a covalent binding between reducing sugars and amino groups of lysine and arginine residues. In this paper the effect of pathological conditions, derived from hyperglycemia on bovine liver catalase (BLC) as a model protein was considered by measuring enzyme activity, reactive oxygen species (ROS) generation, and changes in catalase conformational properties. We observed that in the presence of glucose, the catalase activity gradually decreased. ROS generation was also involved in the glycation process. Thus, decreased BLC activity was partly considered as a result of ROS generation through glycation. However, in the presence of curcumin the amount of ROS was reduced resulting in increased activity of the glycated catalase. The effect of high glucose level and the potential inhibitory effect of curcumin on aggregation and structural changes of catalase were also investigated. Molecular dynamic simulations also showed that interaction of catalase with curcumin resulted in changes in accessible surface area (ASA) and pKa, two effective parameters of glycation, in potential glycation lysine residues. Thus, the decrease in ASA and increase in pKa of important lysine residues were considered as predominant factors in decreased glycation of BLC by curcumin. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Vitiligo susceptibility and catalase gene (CAT) polymorphisms in sicilian population.

    Science.gov (United States)

    Caputo, Valentina; Niceta, Marcello; Fiorella, Santi; La Vecchia, Marco; Bastonini, Emanuela; Bongiorno, Maria R; Pistone, Giuseppe

    2017-02-15

    Catalase gene (CAT) polymorphisms were analyzed as responsible for the deficiency of catalase enzyme activity and concomitant accumulation of excessive hydrogen peroxide in Vitiligo patients. Catalase is a well known oxidative stress regulator that could play an important role in the pathogenesis of Vitiligo. This study was conducted to evaluate three CAT gene polymorphisms (-89A/T, 389C/T, 419C/T) and their association with Vitiligo susceptibility in Sicilian population. 60 out of 73 Sicilian patients with Vitiligo were enrolled and submitted to CAT gene analysis. Contrary to the Northern part of Europe but likewise to the Mediterranean area, the frequency of the CAT genotypes in Sicily is equally distributed. Out of all CAT genotypes, only CAT -89 T/T frequency was found to be significantly higher amongst Vitiligo patients than controls. Despite the involvement of the CAT enzyme in the pathogenesis of Vitiligo, the biological significance of CAT gene polymorphisms is still controversial. With the only exception for CAT variant -89A/T, the other studied CAT gene polymorphisms (389C/T and 419C/T) might not to be associated with Vitiligo in Sicilian population.

  10. Demography of the Brazil nut tree (Bertholletia excelsa) in the Bolivian Amazon : impact of seed extraction on recruitment and population dynamics

    NARCIS (Netherlands)

    Zuidema, P.A.; Boot, R.G.A.

    2002-01-01

    A demographic study was carried out on Bertholletia excelsa, the Brazil nut tree, in two primary forest sites in Northern Bolivia where Brazil nuts have been harvested for several decades. In spite of the large proportion (93€of seeds that are harvested, reasonable densities of recently emerged

  11. Heterosis for superoxide dismutase, peroxidase and catalase ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Genetics; Volume 89; Issue 2. Heterosis for superoxide dismutase, peroxidase and catalase enzymes in the head of single cross-hybrids of cabbage (Brassica oleracea var. capitata). B. K. Singh S. R. Sharma B. Singh. Research Note Volume 89 Issue 2 August 2010 pp 217-221 ...

  12. Binding of Cimetidine to Balb/C Mouse Liver Catalase; Kinetics and Conformational Studies.

    Science.gov (United States)

    Jahangirvand, Mahboubeh; Minai-Tehrani, Dariush; Yazdi, Fatemeh; Minai-Tehrani, Arash; Razmi, Nematollah

    2016-01-01

    Catalase is responsible for converting hydrogen peroxide (H2O2) into water and oxygen in cells. This enzyme has high affinity for hydrogen peroxide and can protect the cells from oxidative stress damage. Catalase is a tetramer protein and each monomer contains a heme group. Cimetidine is a histamine H2 receptor blocker which inhibits acid release from stomach and is used for gasterointestinal diseases. In this research, effect of cimetidine on the activity of liver catalase was studied and the kinetic parameters of this enzyme and its conformational changes were investigated. Cell free extract of mouse liver was used for the catalase assay. The activity of the catalase was detected in the absence and presence of cimetidine by monitoring hydrogen peroxide reduction absorbance at 240 nm. The purified enzyme was used for conformational studies by Fluorescence spectrophotometry. The data showed that cimetidine could inhibit the enzyme in a non-competitive manner. Ki and IC50 values of the drug were determined to be about 0.75 and 0.85 uM, respectively. The Arrhenius plot showed that activation energy was 6.68 and 4.77 kJ/mol in the presence and absence of the drug, respectively. Fluorescence spectrophotometry revealed that the binding of cimetidine to the purified enzyme induced hyperchromicity and red shift which determined the conformational change on the enzyme. Cimetidine could non-competitively inhibit the liver catalase with high affinity. Binding of cimetidine to the enzyme induced conformational alteration in the enzyme.

  13. Cytochemical localization of catalase and several hydrogen peroxide-producing oxidases in the nucleoids and matrix of rat liver peroxisomes

    NARCIS (Netherlands)

    Veenhuis, M.; Wendelaar Bonga, S.E.

    1979-01-01

    The distribution of catalase, amino acid oxidase, α-hydroxy acid oxidase, urate oxidase and alcohol oxidase was studied cytochemically in rat hepatocytes. The presence of catalase was demonstrated with the conventional diaminobenzidine technique. Oxidase activities were visualized with methods based

  14. Reversible adsorption of catalase onto Fe(3+) chelated poly(AAm-GMA)-IDA cryogels.

    Science.gov (United States)

    Aktaş Uygun, Deniz; Uygun, Murat; Akgöl, Sinan; Denizli, Adil

    2015-05-01

    In this presented study, poly(acrylamide-glycidyl methacrylate) [poly(AAm-GMA)] cryogels were synthesized by cryopolymerization technique at sub-zero temperature. Prepared cryogels were then functionalized with iminodiacetic acid (IDA) and chelated with Fe(3+) ions in order produce the metal chelate affinity matrix. Synthesized cryogels were characterized with FTIR, ESEM and EDX analysis, and it was found that the cryogel had sponge like structure with interconnected pores and their pore diameter was about 200 μm. Fe(3+) chelated poly(AAm-GMA)-IDA cryogels were used for the adsorption of catalase and optimum adsorption conditions were determined by varying the medium pH, initial catalase concentration, temperature and ionic strength. Maximum catalase adsorption onto Fe(3+) chelated poly(AAm-GMA)-IDA cryogel was found to be 12.99 mg/g cryogel at 25 °C, by using pH 5.0 acetate buffer. Adsorbed catalase was removed from the cryogel by using 1.0M of NaCl solution and desorption yield was found to be 96%. Additionally, reusability profile of the Fe(3+) chelated poly(AAm-GMA)-IDA cryogel was also investigated and it was found that, adsorption capacity of the cryogels didn't decrease significantly at the end of the 40 reuses. Catalase activity studies were also tested and it was demonstrated that desorbed catalase retained 70% of its initial activity. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. The critical role of catalase in prooxidant and antioxidant function of p53

    Science.gov (United States)

    Kang, M Y; Kim, H-B; Piao, C; Lee, K H; Hyun, J W; Chang, I-Y; You, H J

    2013-01-01

    The tumor suppressor p53 is an important regulator of intracellular reactive oxygen species (ROS) levels, although downstream mediators of p53 remain to be elucidated. Here, we show that p53 and its downstream targets, p53-inducible ribonucleotide reductase (p53R2) and p53-inducible gene 3 (PIG3), physically and functionally interact with catalase for efficient regulation of intracellular ROS, depending on stress intensity. Under physiological conditions, the antioxidant functions of p53 are mediated by p53R2, which maintains increased catalase activity and thereby protects against endogenous ROS. After genotoxic stress, high levels of p53 and PIG3 cooperate to inhibit catalase activity, leading to a shift in the oxidant/antioxidant balance toward an oxidative status, which could augment apoptotic cell death. These results highlight the essential role of catalase in p53-mediated ROS regulation and suggest that the p53/p53R2–catalase and p53/PIG3–catalase pathways are critically involved in intracellular ROS regulation under physiological conditions and during the response to DNA damage, respectively. PMID:22918438

  16. Spectrophotometric assay of catalase with perborate as substrate

    Energy Technology Data Exchange (ETDEWEB)

    Thomson, J.F.; Nance, S.L.; Tollaksen, S.L.

    1978-01-01

    A spectrophotometric assay for catalase has been developed in which sodium perborate, rather than hydrogen peroxide, is used as the substrate. The method is convenient, rapid, and readily adapted to the measurement of catalase in subcellular fractions.

  17. Interactions between carpenter bees and orchid bees (Hymenoptera: Apidae in flowers of Bertholletia excelsa Bonpl. (Lecythidaceae Interações entre abelhas carpinteiras e abelhas das orquídeas (Hymenoptera: Apidae em flores de Bertholletia excelsa Bonpl. (Lecythidaceae

    Directory of Open Access Journals (Sweden)

    Charles Fernando dos Santos

    2012-03-01

    Full Text Available Competition between two species of bees for the same type of floral resource may generate antagonistic behavior between them, especially in cultivated areas where food resources are limited, seasonally and locally. In this study, was tested the hypothesis of antagonism between two solitary bee species of the family Apidae, Eulaema mocsaryi (Euglossini and Xylocopa frontalis (Xylocopini, visiting the Brazil nut flowers (Bertholletia excelsa: Lecythidaceae in a central Amazonia agricultural area. The visitation time was analyzed to detect the possible temporal overlap in the foraging of these bees. Furthermore, was analyzed their interspecific interactions for manipulating flower species visited by an opponent species, as well as attempts to attack this opponent. The individuals of Xylocopa frontalis visited the Brazil nut flowers before Eulaema mocsaryi, although the peak visitation of both did not presented significant differences. Neither of the species manipulated flowers recently visited by opponent species, and there were practically no antagonistic interactions between them. Thus, X. frontalis and E. mocsaryi shared the same food source in the flowers of B. excelsa due to differences in their time of visits and non-aggressive way of interacting with the opponent. This result has important implications for pollinating the Brazil nut, and a possible management of X. frontalis and E. mocsaryi, since these two were the most abundant pollinators in the studied locality.A competição entre duas espécies de abelhas por um mesmo tipo de recurso floral pode gerar comportamentos antagônicos entre elas, principalmente, dentro de áreas cultivadas, onde o recurso alimentar é limitado sazonalmente e localmente. No presente trabalho, foi testada a hipótese de antagonismo entre duas espécies de abelhas solitárias da família Apidae, Eulaema mocsaryi (Euglossini e Xylocopa frontalis (Xylocopini em flores da castanheira do Brasil (Bertholletia

  18. Chromatin remodeling regulates catalase expression during cancer cells adaptation to chronic oxidative stress.

    Science.gov (United States)

    Glorieux, Christophe; Sandoval, Juan Marcelo; Fattaccioli, Antoine; Dejeans, Nicolas; Garbe, James C; Dieu, Marc; Verrax, Julien; Renard, Patricia; Huang, Peng; Calderon, Pedro Buc

    2016-10-01

    Regulation of ROS metabolism plays a major role in cellular adaptation to oxidative stress in cancer cells, but the molecular mechanism that regulates catalase, a key antioxidant enzyme responsible for conversion of hydrogen peroxide to water and oxygen, remains to be elucidated. Therefore, we investigated the transcriptional regulatory mechanism controlling catalase expression in three human mammary cell lines: the normal mammary epithelial 250MK primary cells, the breast adenocarcinoma MCF-7 cells and an experimental model of MCF-7 cells resistant against oxidative stress resulting from chronic exposure to H 2 O 2 (Resox), in which catalase was overexpressed. Here we identify a novel promoter region responsible for the regulation of catalase expression at -1518/-1226 locus and the key molecules that interact with this promoter and affect catalase transcription. We show that the AP-1 family member JunB and retinoic acid receptor alpha (RARα) mediate catalase transcriptional activation and repression, respectively, by controlling chromatin remodeling through a histone deacetylases-dependent mechanism. This regulatory mechanism plays an important role in redox adaptation to chronic exposure to H 2 O 2 in breast cancer cells. Our study suggests that cancer adaptation to oxidative stress may be regulated by transcriptional factors through chromatin remodeling, and reveals a potential new mechanism to target cancer cells. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. A dinuclear manganese(II) complex with the [Mn(2)(mu-O(2)CCH(3))(3)](+) core: synthesis, structure, characterization, electroinduced transformation, and catalase-like activity.

    Science.gov (United States)

    Romero, Isabel; Dubois, Lionel; Collomb, Marie-Noëlle; Deronzier, Alain; Latour, Jean-Marc; Pécaut, Jacques

    2002-04-08

    catalase-like activity has shown that the same species are present in the reaction mixture albeit in slightly different proportions. 2 operates probably along a mechanism different from that of 3 and 5, and the formation of 3 competes with the disproportionation reaction catalyzed by 2. Indeed a solution of 2 exhibits the same activity as 3 for the disproportionation reaction of a second batch of H(2)O(2) indicating that 3 is formed in the course of the reaction.

  20. 21 CFR 184.1034 - Catalase (bovine liver).

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Catalase (bovine liver). 184.1034 Section 184.1034... Listing of Specific Substances Affirmed as GRAS § 184.1034 Catalase (bovine liver). (a) Catalase (bovine liver) (CAS Reg. No. 81457-95-6) is an enzyme preparation obtained from extracts of bovine liver. It is...

  1. 21 CFR 173.135 - Catalase derived from Micrococcus lysodeikticus.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Catalase derived from Micrococcus lysodeikticus... FOOD FOR HUMAN CONSUMPTION Enzyme Preparations and Microorganisms § 173.135 Catalase derived from Micrococcus lysodeikticus. Bacterial catalase derived from Micrococcus lysodeikticus by a pure culture...

  2. Fluorimetry as a Simple and Sensitive Method for Determination of Catalase

    Directory of Open Access Journals (Sweden)

    Mehdi Hedayati

    2014-02-01

    Full Text Available Background: Catalase enzyme plays an important role in the anti-oxidation defense of body so it is important to measure its activity. Nowadays catalase activity measurement is performed by expensive imported kits in various scientific fields. The purpose of this study was to design a sensitive fluorimetry method for measuring catalase activity with improved sensitivity, accuracy and speed. Materials and Methods: In this study, the reaction of hydrogen peroxide with peroxidase (as a reaction accelerator was used in fluorimetry for catalase activity measuring in serum samples in order to increase the sensitivity of the assay. The sensitivity and intra- and inter-assay accuracy, verification test, recovery and parallelism tests, comparison method and correlation and coherence investigation methods were also performed. In order to increase the accuracy and speed of reading, the assay was performed in microplates and reading was done in fluorimetry plates. Results: The percentage of intra- and inter-assay variation coefficients were measured 3.8- 6.6 % and 4.1-7.3%, respectively. Comparison of the results of mentioned method for 50 serum samples with common colorimetric method showed a good correlation (0.917. In assessing the accuracy, the recovery percent was obtained 91% to 107%. The test sensitivity was measured 0.02 IU/ml. Conclusion: The fluorimetry method by microplate reading has a sufficient precision, accuracy and efficiency for catalase activity measuring as well as speed of measurement. Thus it can be an alternative method to conventional imported colorimetric methods.

  3. ICAM-1 targeted catalase encapsulated PLGA-b-PEG nanoparticles against vascular oxidative stress.

    Science.gov (United States)

    Sari, Ece; Tunc-Sarisozen, Yeliz; Mutlu, Hulya; Shahbazi, Reza; Ucar, Gulberk; Ulubayram, Kezban

    2015-01-01

    Targeted delivery of therapeutics is the favourable idea, whereas it is possible to distribute the therapeutically active drug molecule only to the site of action. For this purpose, in this study, catalase encapsulated poly(D,L-lactide-co-glycolide)-block-poly(ethylene glycol) (PLGA-b-PEG) nanoparticles were developed and an endothelial target molecule (anti-ICAM-1) was conjugated to this carrier system in order to decrease the oxidative stress level in the target site. According to the enzymatic activity results, initial catalase activity of nanoparticles was increased from 27.39 U/mg to up to 45.66 U/mg by adding 5 mg/mL bovine serum albumin (BSA). After 4 h, initial catalase activity was preserved up to 46.98% while free catalase retained less than 4% of its activity in proteolytic environment. Furthermore, FITC labelled anti-ICAM-1 targeted catalase encapsulated nanoparticles (anti-ICAM-1/CatNPs) were rapidly taken up by cultured endothelial cells and concomitantly endothelial cells were resistant to H2O2 induced oxidative impairment.

  4. Catalase as a sulfide-sulfur oxido-reductase: An ancient (and modern? regulator of reactive sulfur species (RSS

    Directory of Open Access Journals (Sweden)

    Kenneth R. Olson

    2017-08-01

    Full Text Available Catalase is well-known as an antioxidant dismutating H2O2 to O2 and H2O. However, catalases evolved when metabolism was largely sulfur-based, long before O2 and reactive oxygen species (ROS became abundant, suggesting catalase metabolizes reactive sulfide species (RSS. Here we examine catalase metabolism of H2Sn, the sulfur analog of H2O2, hydrogen sulfide (H2S and other sulfur-bearing molecules using H2S-specific amperometric electrodes and fluorophores to measure polysulfides (H2Sn; SSP4 and ROS (dichlorofluorescein, DCF. Catalase eliminated H2Sn, but did not anaerobically generate H2S, the expected product of dismutation. Instead, catalase concentration- and oxygen-dependently metabolized H2S and in so doing acted as a sulfide oxidase with a P50 of 20 mmHg. H2O2 had little effect on catalase-mediated H2S metabolism but in the presence of the catalase inhibitor, sodium azide (Az, H2O2 rapidly and efficiently expedited H2S metabolism in both normoxia and hypoxia suggesting H2O2 is an effective electron acceptor in this reaction. Unexpectedly, catalase concentration-dependently generated H2S from dithiothreitol (DTT in both normoxia and hypoxia, concomitantly oxidizing H2S in the presence of O2. H2S production from DTT was inhibited by carbon monoxide and augmented by NADPH suggesting that catalase heme-iron is the catalytic site and that NADPH provides reducing equivalents. Catalase also generated H2S from garlic oil, diallyltrisulfide, thioredoxin and sulfur dioxide, but not from sulfite, metabisulfite, carbonyl sulfide, cysteine, cystine, glutathione or oxidized glutathione. Oxidase activity was also present in catalase from Aspergillus niger. These results show that catalase can act as either a sulfide oxidase or sulfur reductase and they suggest that these activities likely played a prominent role in sulfur metabolism during evolution and may continue do so in modern cells as well. This also appears to be the first observation of catalase

  5. Catalase as a sulfide-sulfur oxido-reductase: An ancient (and modern?) regulator of reactive sulfur species (RSS).

    Science.gov (United States)

    Olson, Kenneth R; Gao, Yan; DeLeon, Eric R; Arif, Maaz; Arif, Faihaan; Arora, Nitin; Straub, Karl D

    2017-08-01

    Catalase is well-known as an antioxidant dismutating H2O2 to O2 and H2O. However, catalases evolved when metabolism was largely sulfur-based, long before O2 and reactive oxygen species (ROS) became abundant, suggesting catalase metabolizes reactive sulfide species (RSS). Here we examine catalase metabolism of H2Sn, the sulfur analog of H2O2, hydrogen sulfide (H2S) and other sulfur-bearing molecules using H2S-specific amperometric electrodes and fluorophores to measure polysulfides (H2Sn; SSP4) and ROS (dichlorofluorescein, DCF). Catalase eliminated H2Sn, but did not anaerobically generate H2S, the expected product of dismutation. Instead, catalase concentration- and oxygen-dependently metabolized H2S and in so doing acted as a sulfide oxidase with a P50 of 20mmHg. H2O2 had little effect on catalase-mediated H2S metabolism but in the presence of the catalase inhibitor, sodium azide (Az), H2O2 rapidly and efficiently expedited H2S metabolism in both normoxia and hypoxia suggesting H2O2 is an effective electron acceptor in this reaction. Unexpectedly, catalase concentration-dependently generated H2S from dithiothreitol (DTT) in both normoxia and hypoxia, concomitantly oxidizing H2S in the presence of O2. H2S production from DTT was inhibited by carbon monoxide and augmented by NADPH suggesting that catalase heme-iron is the catalytic site and that NADPH provides reducing equivalents. Catalase also generated H2S from garlic oil, diallyltrisulfide, thioredoxin and sulfur dioxide, but not from sulfite, metabisulfite, carbonyl sulfide, cysteine, cystine, glutathione or oxidized glutathione. Oxidase activity was also present in catalase from Aspergillus niger. These results show that catalase can act as either a sulfide oxidase or sulfur reductase and they suggest that these activities likely played a prominent role in sulfur metabolism during evolution and may continue do so in modern cells as well. This also appears to be the first observation of catalase reductase

  6. Novel nonsense mutation in the katA gene of a catalase-negative Staphylococcus aureus strain.

    Science.gov (United States)

    Lagos, Jaime; Alarcón, Pedro; Benadof, Dona; Ulloa, Soledad; Fasce, Rodrigo; Tognarelli, Javier; Aguayo, Carolina; Araya, Pamela; Parra, Bárbara; Olivares, Berta; Hormazábal, Juan Carlos; Fernández, Jorge

    2016-01-01

    We report the first description of a rare catalase-negative strain of Staphylococcus aureus in Chile. This new variant was isolated from blood and synovial tissue samples of a pediatric patient. Sequencing analysis revealed that this catalase-negative strain is related to ST10 strain, which has earlier been described in relation to S. aureus carriers. Interestingly, sequence analysis of the catalase gene katA revealed presence of a novel nonsense mutation that causes premature translational truncation of the C-terminus of the enzyme leading to a loss of 222 amino acids. Our study suggests that loss of catalase activity in this rare catalase-negative Chilean strain is due to this novel nonsense mutation in the katA gene, which truncates the enzyme to just 283 amino acids. Copyright © 2015 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

  7. A Eukaryote without Catalase-Containing Microbodies : Neurospora crassa Exhibits a Unique Cellular Distribution of Its Four Catalases

    NARCIS (Netherlands)

    Schliebs, Wolfgang; Würtz, Christian; Kunau, Wolf-Hubert; Veenhuis, Marten; Rottensteiner, Hanspeter; Wuertz, Christian

    2006-01-01

    Microbodies usually house catalase to decompose hydrogen peroxide generated within the organelle by the action of various oxidases. Here we have analyzed whether peroxisomes (i.e., catalase-containing microbodies) exist in Neurospora crassa. Three distinct catalase isoforms were identified by native

  8. Reduction of hydrogen peroxide accumulation and toxicity by a catalase from Mycoplasma iowae.

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    Rachel E Pritchard

    Full Text Available Mycoplasma iowae is a well-established avian pathogen that can infect and damage many sites throughout the body. One potential mediator of cellular damage by mycoplasmas is the production of H2O2 via a glycerol catabolic pathway whose genes are widespread amongst many mycoplasma species. Previous sequencing of M. iowae serovar I strain 695 revealed the presence of not only genes for H2O2 production through glycerol catabolism but also the first documented mycoplasma gene for catalase, which degrades H2O2. To test the activity of M. iowae catalase in degrading H2O2, we studied catalase activity and H2O2 accumulation by both M. iowae serovar K strain DK-CPA, whose genome we sequenced, and strains of the H2O2-producing species Mycoplasma gallisepticum engineered to produce M. iowae catalase by transformation with the M. iowae putative catalase gene, katE. H2O2-mediated virulence by M. iowae serovar K and catalase-producing M. gallisepticum transformants were also analyzed using a Caenorhabditis elegans toxicity assay, which has never previously been used in conjunction with mycoplasmas. We found that M. iowae katE encodes an active catalase that, when expressed in M. gallisepticum, reduces both the amount of H2O2 produced and the amount of damage to C. elegans in the presence of glycerol. Therefore, the correlation between the presence of glycerol catabolism genes and the use of H2O2 as a virulence factor by mycoplasmas might not be absolute.

  9. Studies on Microbody Development in Wounded Sweet Potato Root Tissue : Proposal for the Post-Translational Transport of Catalase into Preexisting Microbodies

    OpenAIRE

    Muneharu, ESAKA; Takeshi, TAKAHASHI; Tadashi, Asahi; Laboratory of Biochemistry, Faculty of Agriculture, Nagoya University

    1982-01-01

    Pure microbody fractions could be prepared in considerable yields from sweet potato root tissue slices incubated for 16 hr and 3 days. The ratio of catalase activity to phospholipid content in the fraction from slices incubated for 3 days was about 3 times that from slices incubated for 16 hr. Total catalase activity in the former slices was about twice that in the latter. This suggests that catalase synthesized during incubation ofthe slices is transported into microbodies preexisting in int...

  10. Optimization of catalase biosynthesis in submerged cultures of Aspergillus niger mutant.

    Science.gov (United States)

    Gromada, A; Fiedurek, J

    1997-01-01

    The effect of some medium components, viscous substances and metabolic inhibitors, on catalase production by mutant Aspergillus niger has been studied in shake culture. Altering the composition of the basal medium, particularly substituting NaNO3 for KNO3, and peptone for yeast extract brought an increase in extra- and intracellular catalase activity by 1.5- and 3-fold, respectively. The addition of 2.0-6.0 mg sodium alginate or pectin/ml as viscous additive to the medium, containing glucose as carbon source, increased the medium viscosity and catalase production in shake culture by about 2.8- to 3.0-fold. The highest yield of extracellular catalase activity of A. niger was obtained in the presence of sodium orthovanadate and Triton X-100, which improved the activity of this enzyme by about 1.5-2.2-fold. A significant increase in intracellular catalase activity was observed in the presence of hematin, Tween 80 and sodium orthovanadate (1.7-, 1.6- and 1.4-fold respectively). The time course of growth and enzyme production by A. niger in the optimized medium is also reported.

  11. Novel Role of Endogenous Catalase in Macrophage Polarization in Adipose Tissue.

    Science.gov (United States)

    Park, Ye Seul; Uddin, Md Jamal; Piao, Lingjuan; Hwang, Inah; Lee, Jung Hwa; Ha, Hunjoo

    2016-01-01

    Macrophages are important components of adipose tissue inflammation, which results in metabolic diseases such as insulin resistance. Notably, obesity induces a proinflammatory phenotypic switch in adipose tissue macrophages, and oxidative stress facilitates this switch. Thus, we examined the role of endogenous catalase, a key regulator of oxidative stress, in the activity of adipose tissue macrophages in obese mice. Catalase knockout (CKO) exacerbated insulin resistance, amplified oxidative stress, and accelerated macrophage infiltration into epididymal white adipose tissue in mice on normal or high-fat diet. Interestingly, catalase deficiency also enhanced classical macrophage activation (M1) and inflammation but suppressed alternative activation (M2) regardless of diet. Similarly, pharmacological inhibition of catalase activity using 3-aminotriazole induced the same phenotypic switch and inflammatory response in RAW264.7 macrophages. Finally, the same phenotypic switch and inflammatory responses were observed in primary bone marrow-derived macrophages from CKO mice. Taken together, the data indicate that endogenous catalase regulates the polarization of adipose tissue macrophages and thereby inhibits inflammation and insulin resistance.

  12. Catalase coupled gold nanoparticles: Comparison between carbodiimide and biotin-streptavidin methods

    Science.gov (United States)

    Chirra, Hariharasudhan D.; Sexton, Travis; Biswal, Dipti; Hersh, Louis B.; Hilt, J. Zach

    2011-01-01

    The use of proteins for therapeutic applications requires the protein to maintain sufficient activity for the period of in vivo treatment. Many proteins exhibit a short half-life in vivo and, thus, require delivery systems for them to be applied as therapeutics. The relative biocompatibility and the ability to form functionalized bioconjugates via simple chemistry make gold nanoparticles excellent candidates as protein delivery systems. Herein, two protocols for coupling proteins to gold nanoparticles were compared. In the first, the strong biomolecular binding between biotin and streptavidin was used to couple catalase to the surface of gold nanoparticles. In the second protocol, the formation of an amide bond between carboxylic acid coated gold nanoparticles and free surface amines of catalase using carbodiimide chemistry was performed. The stability and kinetics of the different steps involved in these protocols were studied using UV-Visible spectroscopy, dynamic light scattering, and transmission electron microscopy. The addition of mercaptoundecanoic acid in conjugation with (N-(6-(biotinamido)hexyl)-3′-(2′-pyridyldithio)-propionamide increased the stability of biotinylated gold nanoparticles. Although the carbodiimide chemistry based bioconjugation approach exhibited a decrease in catalase activity, the carbodiimide chemistry based bioconjugation approach resulted in more active catalase per gold nanoparticle compared to that of mercaptoundecanoic acid stabilized biotinylated gold nanoparticles. Both coupling protocols resulted in gold nanoparticles loaded with active catalase. Thus, these gold nanoparticle systems and coupling protocols represent promising methods for the application of gold nanoparticles for protein delivery. PMID:21232642

  13. The role and regulation of catalase in respiratory tract opportunistic bacterial pathogens.

    Science.gov (United States)

    Eason, Mia M; Fan, Xin

    2014-09-01

    Respiratory tract bacterial pathogens are the etiologic agents of a variety of illnesses. The ability of these bacteria to cause disease is imparted through survival within the host and avoidance of pathogen clearance by the immune system. Respiratory tract pathogens are continually bombarded by reactive oxygen species (ROS), which may be produced by competing bacteria, normal metabolic function, or host immunological responses. In order to survive and proliferate, bacteria have adapted defense mechanisms to circumvent the effects of ROS. Bacteria employ the use of anti-oxidant enzymes, catalases and catalase-peroxidases, to relieve the effects of the oxidative stressors to which they are continually exposed. The decomposition of ROS has been shown to provide favorable conditions in which respiratory tract opportunistic bacterial pathogens such as Haemophilus influenzae, Mycobacterium tuberculosis, Legionella pneumophila, and Neisseria meningitidis are able to withstand exposure to highly reactive molecules and yet survive. Bacteria possessing mutations in the catalase gene have a decreased survival rate, yet may be able to compensate for the lack of catalatic activity if peroxidatic activity is present. An incomplete knowledge of the mechanisms by which catalase and catalase-peroxidases are regulated still persists, however, in some bacterial species, a regulatory factor known as OxyR has been shown to either up-regulate or down-regulate catalase gene expression. Yet, more research is still needed to increase the knowledge base in relation to this enzyme class. As with this review, we focus on major respiratory tract opportunistic bacterial pathogens in order to elucidate the function and regulation of catalases. The importance of the research could lead to the development of novel treatments against respiratory bacterial infections. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Cardiac-Specific Overexpression of Catalase Attenuates Lipopolysaccharide-Induced Myocardial Contractile Dysfunction: Role of Autophagy

    Science.gov (United States)

    Turdi, Subat; Han, Xuefeng; Huff, Anna F.; Roe, Nathan D.; Hu, Nan; Gao, Feng; Ren, Jun

    2012-01-01

    Lipopolysaccharide (LPS) from Gram-negative bacteria is a major initiator of sepsis, leading to cardiovascular collapse. Accumulating evidence has indicated a role of reactive oxygen species (ROS) in cardiovascular complication in sepsis. This study was designed to examine the effect of cardiac-specific overexpression of catalase in LPS-induced cardiac contractile dysfunction and the underlying mechanism(s) with a focus on autophagy. Catalase transgenic and wild-type FVB mice were challenged with LPS (6 mg/kg) and cardiac function was evaluated. Levels of oxidative stress, autophagy, apoptosis and protein damage were examined using fluorescence microscopy, Western blot, TUNEL assay, caspase-3 activity and carbonyl formation. Kaplan-Meier curve was constructed for survival following LPS treatment. Our results revealed a lower mortality in catalase mice compared with FVB mice following LPS challenge. LPS injection led to depressed cardiac contractile capacity as evidenced by echocardiography and cardiomyocyte contractile function, the effect of which was ablated by catalase overexpression. LPS treatment induced elevated TNF-α level, autophagy, apoptosis (TUNEL, caspase-3 activation, cleaved caspase-3), production of ROS and O2−, and protein carbonyl formation, the effects of which were significantly attenuated by catalase overexpression. Electron microscopy revealed focal myocardial damage characterized by mitochondrial injury following LPS treatment, which was less severe in catalase mice. Interestingly, LPS-induced cardiomyocyte contractile dysfunction was prevented by antioxidant NAC and the autophagy inhibitor 3-methyladenine. Taken together, our data revealed that catalase protects against LPS-induced cardiac dysfunction and mortality, which may be associated with inhibition of oxidative stress and autophagy. PMID:22902401

  15. Pollination Requirements and the Foraging Behavior of Potential Pollinators of Cultivated Brazil Nut (Bertholletia excelsa Bonpl. Trees in Central Amazon Rainforest

    Directory of Open Access Journals (Sweden)

    M. C. Cavalcante

    2012-01-01

    Full Text Available This study was carried out with cultivated Brazil nut trees (Bertholletia excelsa Bonpl., Lecythidaceae in the Central Amazon rainforest, Brazil, aiming to learn about its pollination requirements, to know the floral visitors of Brazil nut flowers, to investigate their foraging behavior and to determine the main floral visitors of this plant species in commercial plantations. Results showed that B. excelsa is predominantly allogamous, but capable of setting fruits by geitonogamy. Nineteen bee species, belonging to two families, visited and collected nectar and/or pollen throughout the day, although the number of bees decreases steeply after 1000 HR. Only 16, out of the 19 bee species observed, succeeded entering the flower and potentially acted as pollinators. However, due to the abundance, flower frequency and foraging behavior of floral visitors, it was concluded that only the species Eulaema mocsaryi and Xylocopa frontalis could be considered relevant potential pollinators.

  16. Synergistic Roles of Helicobacter pylori Methionine Sulfoxide Reductase and GroEL in Repairing Oxidant-damaged Catalase*

    Science.gov (United States)

    Mahawar, Manish; Tran, ViLinh; Sharp, Joshua S.; Maier, Robert J.

    2011-01-01

    Hypochlorous acid (HOCl) produced via the enzyme myeloperoxidase is a major antibacterial oxidant produced by neutrophils, and Met residues are considered primary amino acid targets of HOCl damage via conversion to Met sulfoxide. Met sulfoxide can be repaired back to Met by methionine sulfoxide reductase (Msr). Catalase is an important antioxidant enzyme; we show it constitutes 4–5% of the total Helicobacter pylori protein levels. msr and katA strains were about 14- and 4-fold, respectively, more susceptible than the parent to killing by the neutrophil cell line HL-60 cells. Catalase activity of an msr strain was much more reduced by HOCl exposure than for the parental strain. Treatment of pure catalase with HOCl caused oxidation of specific MS-identified Met residues, as well as structural changes and activity loss depending on the oxidant dose. Treatment of catalase with HOCl at a level to limit structural perturbation (at a catalase/HOCl molar ratio of 1:60) resulted in oxidation of six identified Met residues. Msr repaired these residues in an in vitro reconstituted system, but no enzyme activity could be recovered. However, addition of GroEL to the Msr repair mixture significantly enhanced catalase activity recovery. Neutrophils produce large amounts of HOCl at inflammation sites, and bacterial catalase may be a prime target of the host inflammatory response; at high concentrations of HOCl (1:100), we observed loss of catalase secondary structure, oligomerization, and carbonylation. The same HOCl-sensitive Met residue oxidation targets in catalase were detected using chloramine-T as a milder oxidant. PMID:21460217

  17. Functional and structural changes of human erythrocyte catalase induced by cimetidine: proposed model of binding.

    Science.gov (United States)

    Yazdi, Fatemeh; Minai-Tehrani, Dariush; Jahngirvand, Mahboubeh; Almasirad, Ali; Mousavi, Zahra; Masoud, Masoudeh; Mollasalehi, Hamidreza

    2015-06-01

    In erythrocyte, catalase plays an important role to protect cells from hydrogen peroxide toxicity. Hydrogen peroxide is a byproduct compound which is produced during metabolic pathway of cells. Cimetidine, a histamine H2 receptor antagonist, is used for gastrointestinal tract diseases and prevents the extra release of gastric acid. In this study, the effect of cimetidine on the activity of human erythrocyte catalase was investigated. Erythrocytes were broken by hypotonic solution. The supernatant was used for catalase assay and kinetics study. Lineweaver-Burk plot was performed to determine the type of inhibition. The kinetics data revealed that cimetidine inhibited the catalase activity by mixed inhibition. The IC50 (1.54 μM) and Ki (0.45 μM) values of cimetidine determined that the drug was bound to the enzyme with high affinity. Circular dichroism and fluorescence measurement showed that the binding of cimetidine to the enzyme affected the content of secondary structure of the enzyme as well as its conformational changes. Docking studies were carried out to detect the site in which the drug was bound to the enzyme. Molecular modeling and energy calculation of the binding showed that the cyanoguanidine group of the drug connected to Asp59 via two hydrogen bonds, while the imidazole group of the drug interacted with Phe64 in the enzyme by a hydrophobic interaction. In conclusion, cimetidine could bind to human erythrocyte catalase, and its interaction caused functional and conformational changes in the enzyme.

  18. Hydrogen peroxide scavenger, catalase, alleviates ion transport dysfunction in murine colitis.

    Science.gov (United States)

    Barrett, Kim E; McCole, Declan F

    2016-11-01

    Reactive oxygen species (ROS) such as hydrogen peroxide (H2 O2 ) contribute to epithelial damage and ion transport dysfunction (key events in inflammatory diarrhoea) in inflammatory bowel disease (IBD). The aim of this study was to identify if H2 O2 mediates suppression of colonic ion transport function in the murine dextran sulfate sodium (DSS) colitis model by using the H2 O2 degrading enzyme, catalase. Colitis was induced by administering DSS (4%) in drinking water for 5 days followed by 3 days on normal H2 O. Mice were administered either pegylated catalase or saline at day -1, 0 and +1 of DSS treatment. Ion transport responses to the Ca2+ -dependent agonist, carbachol (CCh), or the cAMP-dependent agonist, forskolin, were measured across distal colonic mucosa mounted in Ussing chambers. Parameters of DSS-induced inflammation (loss in body weight, decreased colon length, altered stool consistency), were only partially alleviated by catalase while histology was only minimally improved. However, catalase significantly reversed the DSS-induced reduction in baseline ion transport as well as colonic Isc responses to CCh. However, ion transport responses to forskolin were not significantly restored. Catalase also reduced activation of ERK MAP kinase in the setting of colitis, and increased expression of the Na+ -K+ -2Cl- cotransporter, NKCC1, consistent with restoration of ion transport function. Ex vivo treatment of inflamed colonic mucosae with catalase also partially restored ion transport function. Therefore, catalase partially prevents, and rescues, the loss of ion transport properties in DSS colitis even in the setting of unresolved tissue inflammation. These findings indicate a prominent role for ROS in ion transport dysfunction in colitis and may suggest novel strategies for the treatment of inflammatory diarrhoea. © 2016 John Wiley & Sons Australia, Ltd.

  19. The monofunctional catalase KatE of Xanthomonas axonopodis pv. citri is required for full virulence in citrus plants.

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    María Laura Tondo

    Full Text Available BACKGROUND: Xanthomonas axonopodis pv. citri (Xac is an obligate aerobic phytopathogen constantly exposed to hydrogen peroxide produced by normal aerobic respiration and by the plant defense response during plant-pathogen interactions. Four putative catalase genes have been identified in silico in the Xac genome, designated as katE, catB, srpA (monofunctional catalases and katG (bifunctional catalase. METHODOLOGY/PRINCIPAL FINDINGS: Xac catalase activity was analyzed using native gel electrophoresis and semi-quantitative RT-PCR. We demonstrated that the catalase activity pattern was regulated in different growth stages displaying the highest levels during the stationary phase. KatE was the most active catalase in this phase of growth. At this stage cells were more resistant to hydrogen peroxide as was determined by the analysis of CFU after the exposition to different H(2O(2 concentrations. In addition, Xac exhibited an adaptive response to hydrogen peroxide, displaying higher levels of catalase activity and H(2O(2 resistance after treatment with sub-lethal concentrations of the oxidant. In the plant-like medium XVM2 the expression of KatE was strongly induced and in this medium Xac was more resistant to H(2O(2. A XackatE mutant strain was constructed by insertional mutagenesis. We observed that catalase induction in stationary phase was lost meanwhile the adaptive response to peroxide was maintained in this mutant. Finally, the XackatE strain was assayed in planta during host plant interaction rendering a less aggressive phenotype with a minor canker formation. CONCLUSIONS: Our results confirmed that in contrast to other Xanthomonas species, Xac catalase-specific activity is induced during the stationary phase of growth in parallel with the bacterial resistance to peroxide challenge. Moreover, Xac catalases expression pattern is modified in response to any stimuli associated with the plant or the microenvironment it provides. The catalase Kat

  20. Ectopic catalase expression in mitochondria by adeno-associated virus enhances exercise performance in mice.

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    Dejia Li

    2009-08-01

    Full Text Available Oxidative stress is thought to compromise muscle contractility. However, administration of generic antioxidants has failed to convincingly improve performance during exhaustive exercise. One possible explanation may relate to the inability of the supplemented antioxidants to effectively eliminate excessive free radicals at the site of generation. Here, we tested whether delivering catalase to the mitochondria, a site of free radical production in contracting muscle, could improve treadmill performance in C57Bl/6 mice. Recombinant adeno-associated virus serotype-9 (AV.RSV.MCAT was generated to express a mitochondria-targeted catalase gene. AV.RSV.MCAT was delivered to newborn C57Bl/6 mouse circulation at the dose of 10(12 vector genome particles per mouse. Three months later, we observed a approximately 2 to 10-fold increase of catalase protein and activity in skeletal muscle and the heart. Subcellular fractionation western blot and double immunofluorescence staining confirmed ectopic catalase expression in the mitochondria. Compared with untreated control mice, absolute running distance and body weight normalized running distance were significantly improved in AV.RSV.MCAT infected mice during exhaustive treadmill running. Interestingly, ex vivo contractility of the extensor digitorum longus muscle was not altered. Taken together, we have demonstrated that forced catalase expression in the mitochondria enhances exercise performance. Our result provides a framework for further elucidating the underlying mechanism. It also raises the hope of applying similar strategies to remove excessive, pathogenic free radicals in certain muscle diseases (such as Duchenne muscular dystrophy and ameliorate muscle disease.

  1. Freezability of water buffalo spermatozoa is improved with the addition of catalase in cryodiluent.

    Science.gov (United States)

    Ali, L; Hassan Andrabi, S M; Ahmed, H; Hussain Shah, A A

    Catalase enzyme is usually distributed in mammalian seminal plasma, where it decomposes hydrogen peroxide into water and oxygen and enhances sperm survivability. To evaluate the effect of catalase (0, 100, 200 or 300 IU/ml) added in tris-citric acid (TCA) based extender on motion characteristics, viability and DNA integrity of bubaline spermatozoa at post dilution (PD) and post thawing (PT) stages of cryopreservation. Collection of semen was done in four Nili-Ravi bulls with an artificial vagina (42 degree C). Qualified semen samples from each bull were further subdivided into four aliquots for dilution with the experimental TCA extender containing either 0.0 (T1), 100 IU (T2), 200 IU (T3) or 300 IU (T4) catalase (activity12660 U/mg). At PT, mean computer progressive motility, average path velocity, straight line velocity, curvilinear velocity, visual motility and DNA integrity were higher (P catalase fortified treatment groups as compared with control. Regarding plasma membrane integrity and supra-vital plasma membrane integrity, at PT the mean values were higher (P catalase at a concentration of 300IU/ml in TCA cryodiluent improved the freezability of water buffalo spermatozoa.

  2. Forchlorfenuron detection based on its inhibitory effect towards catalase immobilized on boron nitride substrate.

    Science.gov (United States)

    Xu, Qin; Cai, Lijuan; Zhao, Huijie; Tang, Jiaqian; Shen, Yuanyuan; Hu, Xiaoya; Zeng, Haibo

    2015-01-15

    An enzymatic procedure based on a catalase biosensor for the detection of forchlorfenuron (CPPU) has been reported in this work. Catalase was immobilized on boron nitride (BN) sheets dispersed in chitosan by adsorption. The immobilized catalase exhibited direct electron transfer character and excellent electrocatalytic activity towards H2O2 reduction. After introducing CPPU into the H2O2 containing phosphate buffer solution, the catalase-catalyzed H2O2 reduction current decreased. By measuring the current decrease, CPPU can be determined in the range of 0.5-10.0 µM with the detection limit of 0.07 μM. The non-competitive inhibition behavior of CPPU towards catalase was verified by the Lineweaver-Burk plots. Long stability character has been ascribed to this biosensor. Possible use of this biosensor in flow systems is illustrated. The proposed biosensor has been successfully applied to CPPU determination in fruits samples with satisfactory results. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Assessment of catalase activity, lipid peroxidation, chlorophyll-a, and growth rate in the freshwater green algae Pseudokirchneriella subcapitata exposed to copper and zinc Evaluación de la actividad de la catalasa, peroxidación lipídica, clorofila-a y tasa de crecimiento en la alga verde de agua dulce Pseudokirchneriella subcapitata expuesta a cobre y zinc

    Directory of Open Access Journals (Sweden)

    Paulina Soto

    2011-07-01

    Full Text Available In this work, the effect of copper and zinc on green alga Pseudokirchneriella subcapitata was evaluated through catalase activity, lipid peroxidation by TBARS essay, growth rate, and the chlorophyll-a concentration. Catalase activity increased significantly (P En este trabajo, se evaluó el efecto del cobre y zinc en la alga verde Pseudokirchneriella subcapitata a través de la actividad catalasa, peroxidación lipídica por el ensayo TBARS, tasa de crecimiento y concentración de clorofila-a. La actividad catalasa aumentó significativamente (P < 0,05 en comparación al control en 0,1 mg L-1 y 0,075 mg L-1 de cobre y zinc respectivamente, mientras que el daño en la membrana celular expresado en nanomols/10(6 células de malondialdehído aumentó significativamente en 0,025 mg L-1 y 0,1 mg L-1 de cobre y zinc respectivamente. Por otra parte, hubo una disminución significativa (P < 0,05 en la concentración de clorofila-a en ambos metales a 0,075 mgL-1. Los resultados mostrados en actividad catalasa, peroxidación lipídica y concentración de clorofila-a son parámetros más sensibles que la tasa de crecimiento a los metales.

  4. Inhibitors of Catalase-Amyloid Interactions Protect Cells from β-Amyloid-Induced Oxidative Stress and Toxicity*

    Science.gov (United States)

    Habib, Lila K.; Lee, Michelle T. C.; Yang, Jerry

    2010-01-01

    Compelling evidence shows a strong correlation between accumulation of neurotoxic β-amyloid (Aβ) peptides and oxidative stress in the brains of patients afflicted with Alzheimer disease (AD). One hypothesis for this correlation involves the direct and harmful interaction of aggregated Aβ peptides with enzymes responsible for maintaining normal, cellular levels of reactive oxygen species (ROS). Identification of specific, destructive interactions of Aβ peptides with cellular anti-oxidant enzymes would represent an important step toward understanding the pathogenicity of Aβ peptides in AD. This report demonstrates that exposure of human neuroblastoma cells to cytotoxic preparations of aggregated Aβ peptides results in significant intracellular co-localization of Aβ with catalase, an anti-oxidant enzyme responsible for catalyzing the degradation of the ROS intermediate hydrogen peroxide (H2O2). These catalase-Aβ interactions deactivate catalase, resulting in increased cellular levels of H2O2. Furthermore, small molecule inhibitors of catalase-amyloid interactions protect the hydrogen peroxide-degrading activity of catalase in Aβ-rich environments, leading to reduction of the co-localization of catalase and Aβ in cells, inhibition of Aβ-induced increases in cellular levels of H2O2, and reduction of the toxicity of Aβ peptides. These studies, thus, provide evidence for the important role of intracellular catalase-amyloid interactions in Aβ-induced oxidative stress and propose a novel molecular strategy to inhibit such harmful interactions in AD. PMID:20923778

  5. Specific Function of the Met-Tyr-Trp Adduct Radical and Residues Arg-418 and Asp-137 in the Atypical Catalase Reaction of Catalase-Peroxidase KatG*

    Science.gov (United States)

    Zhao, Xiangbo; Khajo, Abdelahad; Jarrett, Sanchez; Suarez, Javier; Levitsky, Yan; Burger, Richard M.; Jarzecki, Andrzej A.; Magliozzo, Richard S.

    2012-01-01

    Catalase activity of the dual-function heme enzyme catalase-peroxidase (KatG) depends on several structural elements, including a unique adduct formed from covalently linked side chains of three conserved amino acids (Met-255, Tyr-229, and Trp-107, Mycobacterium tuberculosis KatG numbering) (MYW). Mutagenesis, electron paramagnetic resonance, and optical stopped-flow experiments, along with calculations using density functional theory (DFT) methods revealed the basis of the requirement for a radical on the MYW-adduct, for oxyferrous heme, and for conserved residues Arg-418 and Asp-137 in the rapid catalase reaction. The participation of an oxyferrous heme intermediate (dioxyheme) throughout the pH range of catalase activity is suggested from our finding that carbon monoxide inhibits the activity at both acidic and alkaline pH. In the presence of H2O2, the MYW-adduct radical is formed normally in KatG[D137S] but this mutant is defective in forming dioxyheme and lacks catalase activity. KatG[R418L] is also catalase deficient but exhibits normal formation of the adduct radical and dioxyheme. Both mutants exhibit a coincidence between MYW-adduct radical persistence and H2O2 consumption as a function of time, and enhanced subunit oligomerization during turnover, suggesting that the two mutations disrupting catalase turnover allow increased migration of the MYW-adduct radical to protein surface residues. DFT calculations showed that an interaction between the side chain of residue Arg-418 and Tyr-229 in the MYW-adduct radical favors reaction of the radical with the adjacent dioxyheme intermediate present throughout turnover in WT KatG. Release of molecular oxygen and regeneration of resting enzyme are thereby catalyzed in the last step of a proposed catalase reaction. PMID:22918833

  6. HIF-mediated increased ROS from reduced mitophagy and decreased catalase causes neocytolysis.

    Science.gov (United States)

    Song, Jihyun; Yoon, Donghoon; Christensen, Robert D; Horvathova, Monika; Thiagarajan, Perumal; Prchal, Josef T

    2015-08-01

    During prolonged hypoxia, hypoxia-inducible factors (HIFs) mediate an increase in erythropoiesis, leading to an increased red blood cell (RBC) mass and polycythemia. Upon return to normoxia, the increased RBC mass is abruptly overcorrected by the preferential destruction of hypoxia-formed young RBCs, a phenomenon termed neocytolysis. The molecular and biochemical mechanisms involved in neocytolysis are unknown. We developed a murine model of neocytolysis by exposing mice to 12 % oxygen for 10 days followed by return to normoxia. Upon return to normoxia, there was excessive accumulation of reactive oxygen species (ROS) in RBCs from an increased reticulocyte mitochondrial mass correlating with decreased Bnip3L transcripts (Bnip3L mediates reticulocyte mitophagy) and reduced catalase activity. During hypoxia, upregulated miR-21 resulted in low catalase activity in young RBCs. Furthermore, neocytolysis was attenuated by antioxidants and plasma catalase and blunted in mice that had constitutively high expression of HIFs. Among human neonates studied, we report data supporting the existence of neocytolysis during the first week of life. Together, these experiments indicate that the major mechanisms causing neocytolysis involve (1) production of young RBCs with low catalase during hypoxia and (2) lysis of the young RBCs after return to normoxia, mediated by ROS from an increased mitochondrial mass. We report a mouse model of neocytolysis. Neocytolysis is caused by excessive ROS formation mediated by HIF. ROS is generated from increased mitochondria in reticulocytes. Hypoxia-generated RBCs have low catalase and are preferentially destroyed. Reduced catalase is regulated by increased microRNA-21.

  7. Purification, cloning, expression, and biochemical characterization of a monofunctional catalase, KatP, from Pigmentiphaga sp. DL-8.

    Science.gov (United States)

    Dong, Weiliang; Hou, Ying; Li, Shuhuan; Wang, Fei; Zhou, Jie; Li, Zhoukun; Wang, Yicheng; Huang, Fei; Fu, Lei; Huang, Yan; Cui, Zhongli

    2015-04-01

    Catalases are essential components of the cellular equipment used to cope with oxidative stress. The monofunctional catalase KatP was purified from Pigmentiphaga sp. using ammonium sulfate precipitation (ASP), diethylaminoethyl ion exchange chromatography (IEC), and hydrophobic interaction chromatography (HIC). The purified catalase formed polymer with an estimated monomer molecular mass of 54kDa, which were resolved by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and zymogram analysis. KatP exhibited a specific catalytic activity of 73,000U/mg, which was higher than that of catalase-1 of Comamonas terrigena N3H (55,900U/mg). Seven short tryptic fragments of this catalase were obtained by electrospray ionization quadrupole time-of-flight mass spectrometry (ESI-Q-TOF MS/MS), and the gene, katP, was cloned by PCR amplification and overexpressed in Escherichia coli BL21 (DE3). Based on the complete amino acid sequence, KatP was identified as a clade 3 monofunctional catalase. The specific activities of recombinant KatP for hydrogen peroxide (690,000U/mg) increased 9-fold over that of the parent strain. The Km and Vmax of recombinant KatP were 9.48mM and 81.2mol/minmg, respectively. The optimal pH and temperature for KatP were 7.0 and 37°C, respectively, and the enzyme displayed abroad pH-stable range of 4.0-11.0. The enzyme was inhibited by Zn(2+), Cu(2+), Cr(2+), and Mn(2+), whereas Fe(3+) and Mg(2+) stimulated KatP enzymatic activity. Interestingly, the catalase activity of recombinant KatP displayed high stability under different temperature and pH conditions, suggesting that KatP is a potential candidate for the production of catalase. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Heterologous expression and characterization of a new heme-catalase in Bacillus subtilis 168.

    Science.gov (United States)

    Philibert, Tuyishime; Rao, Zhiming; Yang, Taowei; Zhou, Junping; Huang, Genshu; Irene, Komera; Samuel, Niyomukiza

    2016-06-01

    Reactive oxygen species (ROS) is an inherent consequence to all aerobically living organisms that might lead to the cells being lethal and susceptible to oxidative stress. Bacillus pumilus is characterized by high-resistance oxidative stress that stimulated our interest to investigate the heterologous expression and characterization of heme-catalase as potential biocatalyst. Results indicated that recombinant enzyme significantly exhibited the high catalytic activity of 55,784 U/mg expressed in Bacillus subtilis 168 and 98.097 µmol/min/mg peroxidatic activity, the apparent K m of catalytic activity was 59.6 ± 13 mM with higher turnover rate (K cat = 322.651 × 10(3) s(-1)). The pH dependence of catalatic and peroxidatic activity was pH 7.0 and pH 4.5 respectively with temperature dependence of 40 °C and the recombinant heme-catalase exhibited a strong Fe(2+) preference. It was further revealed that catalase KatX2 improved the resistance oxidative stress of B. subtilis. These findings suggest that this B. pumilus heme-catalase can be considered among the industrially relevant biocatalysts due to its exceptional catalytic rate and high stability and it can be a potential candidate for the improvement of oxidative resistance of industrially produced strains.

  9. RAPD fingerprint to appraise the genetic fidelity of in vitro propagated Araucaria excelsa R. Br. var. glauca plantlets.

    Science.gov (United States)

    Sarmast, Mostafa Khoshhal; Salehi, Hassan; Ramezani, Amin; Abolimoghadam, Ali Asghar; Niazi, Ali; Khosh-Khui, Morteza

    2012-03-01

    Randomly amplified polymorphic DNA (RAPD) was used as a tool to assess the genetic fidelity of in vitro propagated Araucaria excelsa R. Br. var. glauca with explants taken from orthotropic stem along with their related mother plants after treatment with kinetin, 2iP, BA (0.02-0.26 mg/l) and TDZ (0.001-1 mg/l) to produce axillary shoots. TDZ and kinetin induced more shoot and higher length per explant. Results showed a total of 1,676 fragments were generated with 12 RAPD primers in micropropagated plants and their donor mother plants. The number of loci ranged from 6 in OPB 12-18 in OPY 07 with a size ranging from 250 bp in OPH 19-3500 bp in OPH 11. Cluster analysis of RAPD data using UPGMA (unweighted pair group method with arithmetic average) revealed more than 92% genetic similarities between tissue cultured plants and their corresponding mother plant measured by the Jaccard's similarity coefficient. Similarity matrix and PCoA (two dimensional principal coordinate analysis) resulted in the same affinity. Primers had shown 36% polymorphism. However, careful monitoring of tissue culture derived plants might be needed to determine that rooted shoots are adventitious in origin.

  10. Peroxisomal catalase deficiency modulates yeast lifespan depending on growth conditions

    NARCIS (Netherlands)

    Kawalek, Adam; Lefevre, Sophie D.; Veenhuis, Marten; van der Klei, Ida J.

    We studied the role of peroxisomal catalase in chronological aging of the yeast Hansenula polymorpha in relation to various growth substrates. Catalase-deficient (cat) cells showed a similar chronological life span (CLS) relative to the wild-type control upon growth on carbon and nitrogen sources

  11. Spectrophotometric assay of catalase with perborate as substrate

    Energy Technology Data Exchange (ETDEWEB)

    Thomson, J.R.; Nance, S.L.; Tollaksen, S.L.

    1978-01-01

    A spectrophotometric assay for catalase in mouse liver fractions has been developed in which sodium perborate, rather than hydrogen peroxide, is used as the substrate. The method is convenient, rapid, and readily adapted to the measurement of catalase in subcellular fractions.

  12. Vascular endothelium-specific overexpression of human catalase in cloned pigs.

    Science.gov (United States)

    Whyte, J J; Samuel, M; Mahan, E; Padilla, J; Simmons, G H; Arce-Esquivel, A A; Bender, S B; Whitworth, K M; Hao, Y H; Murphy, C N; Walters, E M; Prather, R S; Laughlin, M H

    2011-10-01

    The objective of this study was to develop transgenic Yucatan minipigs that overexpress human catalase (hCat) in an endothelial-specific manner. Catalase metabolizes hydrogen peroxide (H(2)O(2)), an important regulator of vascular tone that contributes to diseases such as atherosclerosis and preeclampsia. A large animal model to study reduced endothelium-derived H(2)O(2) would therefore generate valuable translational data on vascular regulation in health and disease. Yucatan minipig fetal fibroblasts stably co-transfected with human catalase (Tie2-hCat) and eGFP expression constructs were isolated into single-cell populations. The presence of the Tie2-hCat transgene in individual colonies of fibroblasts was determined by PCR. Transgenic fibroblasts were used for nuclear transfer into enucleated oocytes by electrofusion. A minimum of 140 cloned embryos were transferred per surrogate sow (n = 4). All four surrogates maintained pregnancies and piglets were delivered by cesarean section. Nine male piglets from three of the four litters carried the Tie2-hCat transgene. Expression of human catalase mRNA and overall elevated catalase protein in isolated umbilical endothelial cells from transgenic piglets were verified by RT-PCR and western blot, respectively, and endothelial localization was confirmed by immunohistochemistry. Increased enzymatic activity of catalase in transgenic versus wild-type endothelial cells was inferred based on significantly reduced levels of H(2)O(2) in culture. The similarities in swine and human cardiovascular anatomy and physiology will make this pig model a valuable source of information on the putative role of endothelium-derived H(2)O(2) in vasodilation and in the mechanisms underlying vascular health and disease.

  13. Catalase therapy corrects oxidative stress-induced pathophysiology in incipient diabetic retinopathy.

    Science.gov (United States)

    Giordano, Courtney R; Roberts, Robin; Krentz, Kendra A; Bissig, David; Talreja, Deepa; Kumar, Ashok; Terlecky, Stanley R; Berkowitz, Bruce A

    2015-05-01

    Preclinical studies have highlighted retinal oxidative stress in the pathogenesis of diabetic retinopathy. We evaluated whether a treatment designed to enhance cellular catalase reduces oxidative stress in retinal cells cultured in high glucose and in diabetic mice corrects an imaging biomarker responsive to antioxidant therapy (manganese-enhanced magnetic resonance imaging [MEMRI]). Human retinal Müller and pigment epithelial cells were chronically exposed to normal or high glucose levels and treated with a cell-penetrating derivative of the peroxisomal enzyme catalase (called CAT-SKL). Hydrogen peroxide (H2O2) levels were measured using a quantitative fluorescence-based assay. For in vivo studies, streptozotocin (STZ)-induced diabetic C57Bl/6 mice were treated subcutaneously once a week for 3 to 4 months with CAT-SKL; untreated age-matched nondiabetic controls and untreated diabetic mice also were studied. MEMRI was used to analytically assess the efficacy of CAT-SKL treatment on diabetes-evoked oxidative stress-related pathophysiology in vivo. Similar analyses were performed with difluoromethylornithine (DFMO), an irreversible inhibitor of ornithine decarboxylase. After catalase transduction, high glucose-induced peroxide production was significantly lowered in both human retinal cell lines. In diabetic mice in vivo, subnormal intraretinal uptake of manganese was significantly improved by catalase supplementation. In addition, in the peroxisome-rich liver of treated mice catalase enzyme activity increased and oxidative damage (as measured by lipid peroxidation) declined. On the other hand, DFMO was largely without effect in these in vitro or in vivo assays. This proof-of-concept study raises the possibility that augmentation of catalase is a therapy for treating the retinal oxidative stress associated with diabetic retinopathy.

  14. Catalase expression is modulated by vancomycin and ciprofloxacin and influences the formation of free radicals in Staphylococcus aureus cultures

    DEFF Research Database (Denmark)

    Wang, Ying; Hougaard, Anni Bygvrå; Paulander, Wilhelm Erik Axel

    2015-01-01

    was detected in broth medium without bacterial cells present and it was mitigated by iron chelation or by addition of catalase, which catalyzes the decomposition of hydrogen peroxide to water and oxygen. This suggests that the signal originates from hydroxyl radicals formed by the Fenton reaction, in which...... compared to the level seen with untreated bacterial cells. However, S. aureus cells express catalase, and the antibiotic-mediated increase in hydroxyl radical formation was correlated with reduced katA expression and catalase activity in the presence of either antibiotic. Therefore, our results show...... that in S. aureus, bactericidal antibiotics modulate catalase expression, which in turn influences the formation of free radicals in the surrounding broth medium. If similar regulation is found in other bacterial species, it might explain why bactericidal antibiotics are perceived as inducing formation...

  15. Aspectos silviculturais da castanha-do-brasil (Bertholletia excelsa em sistemas agroflorestais na Amazônia Central Silvicultural aspects of Brazil nut (Bertholletia excelsa in agroforestry systems in Central Amazonia

    Directory of Open Access Journals (Sweden)

    Joanne Régis Costa

    2009-01-01

    Full Text Available Este estudo avaliou o desempenho da castanha-do-brasil (Bertholletia excelsa em sistemas agroflorestais implantados em ecossistema de terra firme na Amazônia Central. Foram avaliados 3 sítios de sistemas agroflorestais multi-estratificados, implantados em 1992, em áreas de pastagens degradadas, situadas no km 54 da BR-174, no Campo Experimental da Embrapa Amazônia Ocidental, em Manaus (AM. Os sistemas foram implantados após o processo tradicional de derruba e queima da vegetação secundária estabelecida em pastagens submetidas por 6 anos ao pastejo intensivo e abandonadas por 4 anos, em média, ao processo de regeneração natural. O desempenho da espécie com 12 anos de idade foi avaliado por meio do diâmetro à altura do peito (DAP, da altura total, da taxa de sobrevivência e das variáveis morfométricas "Diâmetro da Copa", "Proporção de Copa", "Grau de Esbeltez", "índice de Saliência", "índice de Abrangência" e "Forma de Copa". Os indivíduos atingiram altura total média de 20,9 m e DAP de 37,9 cm, com incremento médio anual de 1,74 m e 3,16cm, respectivamente. A porcentagem média de sobrevivência foi de 78%, cuja mortalidade foi relacionada às ventanias e raios. Os resultados indicaram a eficiência dessa espécie para reabilitar áreas degradadas e confirmaram-na como uma espécie adequada para formar sistemas agroflorestais.This study evaluated the development of Brasil nut (Bertholletia excelsa in agroforestry systems established on non-flooding plateaus in Central Amazonia. Three multi-strata agroforestry systems established in 1992 in degraded pastures, located at the Experiment Station of Embrapa Amazonia Ocidental, BR-174 highway, km 54, Manaus, Amazonas, were evaluated. The area had been intensively managed as pasture for six years, then abandoned for four years, and reopened with traditional slash and burn practices to plant the agroforestry systems. Species development was evaluated with measurements of

  16. Induction and inactivation of catalase and superoxide dismutase of Escherichia coli by ozone

    Energy Technology Data Exchange (ETDEWEB)

    Whiteside, C.; Hassan, H.M.

    1987-09-01

    Oxyradicals have been implicated in ozone (O/sub 3/) toxicity and in other oxidant stress. In this study, we investigated the effects of O/sub 3/ on the biosynthesis of the antioxidant enzymes catalase and superoxide dismutase in Escherichia coli to determine their role in the defense against ozone toxicity. Inhibition of growth and loss of viability were observed in cultures exposed to ozone. Results also showed an increase in the activities of catalase and superoxide dismutase in cultures exposed to ozone, which was shown to be due to true induction rather than activation of preexisting apoproteins. Cessation of O/sub 3/ exposure resulted in 30 min of continual high rate of catalase biosynthesis followed by a gradual decrease in the level of the enzyme approaching that of control cultures. This decrease was attributed to a concomitant cessation of de novo enzyme synthesis and dilution of preexisting enzyme by cellular growth. Ozonation of cell-free extracts showed that superoxide dismutase and catalase are subject to oxidative inactivation by ozone. In vivo induction of these enzymes may represent an adaptive response evolved to protect cells against ozone toxicity.

  17. Screening of agricultural wastes as a medium production of catalase for enzymatic fuel cell by Neurospora crassa InaCC F226

    Science.gov (United States)

    Santoso, Pugoh; Yopi

    2017-12-01

    Explorations of local microorganisms from Indonesia that can produce of catalase are still limited. Neurospora crassa is a fungus which resulting of two kinds of catalase, namely catalase-1 and catalase-3. We studied the production of catalase by Neurospora crassa (no. F226) from Indonesia Culture Collection (InaCC) in Solid State Fermentation (SSF). Among four screened agro wastes (corn cob, rice straw, oil palm empty fruit bunches, and bagasse), rice straw and oil palm empty fruit bunches (OPEFB) were remarked as the most promising substrate suited for the excellent growth and adequate production of catalase. Based on the result, the method of solid state fermentation was suitable to production of catalase. It is caused that the medium served to maintain microbial growth and metabolism. The filamentous filament is more suitable for living on solid media because it has a high tolerance to low water activity, and it has a high potential to excrete hydrolytic enzymes that caused of its morphology. The filamentous filament morphology allows the fungus to form colonies and penetrate the solid substrates in order to obtain nutrients. The results showed that the highest catalase activity was obtained on rice straw and oil palm empty fruit bunches medium with catalase activity of 39.1 U/mL and 37,7 U/mL in 50% moisture content medium, respectively. Optimization of humidity and pH medium in the rice straw were investigated which is the highest activity obtained in 30% moisture content and pH medium of 6. The catalase activity was reached in the value of 53.761 U/mL and 56.903 U/mL by incubated 48 hours and 96 hours, respectively.

  18. Brain catalase mediates potentiation of social recognition memory produced by ethanol in mice.

    Science.gov (United States)

    Manrique, Héctor M; Miquel, Marta; Aragon, Carlos M G

    2005-09-01

    The involvement of catalase in ethanol-induced locomotion has been clearly proven. However, studies addressing the role of this enzyme in the effects that ethanol exerts on memory are lacking. In the present study, the social recognition test (SRT) was used to evaluate ethanol effects on memory. In this test, the reduction in investigation time of a juvenile conspecific, when this social stimulus is presented for the second time, is considered a reliable index of memory. Exploration ratios (ER) were calculated to evaluate the recognition capacity of mice. Ethanol (0.0, 0.5, 1.0 or 1.5g/kg, i.p.) was administered immediately after the first juvenile presentation, and 2h later the juvenile was re-exposed to the adult. Additionally, adult mice received aminotriazole (AT) or sodium azide (two catalase inhibitors) 5h or 30 min before juvenile presentation, respectively. Ethanol (1.0 and 1.5g/kg) was able to reduce ER, indicating an improving effect on memory. This improvement was prevented by either AT or sodium azide pre-treatment. However, neither AT nor sodium azide attenuated the memory-enhancing capacity of NMDA or nicotine, suggesting a specific interaction between catalase inhibitors and ethanol in their effects on memory. The present results suggest that brain catalase activity could mediate the memory-enhancing capacity of ethanol and add further support to the idea that this enzyme mediates some of the psychopharmacological effects produced by ethanol.

  19. A study of the inhibition of catalase by dipotassium trioxohydroxytetrafluorotriborate K₂[B₃O₃F₄OH].

    Science.gov (United States)

    Islamovic, Safija; Galic, Borivoj; Milos, Mladen

    2014-10-01

    In the development of boronic acid-based enzyme inhibitors as potential pharmaceutical drugs, dipotassium trioxohydroxytetrafluorotriborate K2[B3O3F4OH] was listed as a promising new therapeutic for treatment of these diseases. The catalase-mediated conversion of hydrogen peroxide, in the presence and absence of K2[B3O3F4OH] was studied. The kinetics conformed to the Michaelis-Menten model. Lineweaver-Burk plots were linear and plotted the family of straight lines intersected on the abscissa indicating non-competitive inhibition of the catalase. It appears that in the absence of inhibitor, catalase operates the best at conditions around pH 7.1 and in the presence of K2[B3O3F4OH] the optimum is around pH 6.2. The uncatalyzed reaction of hydrogen peroxide decomposition generally has a value of activation energy of 75 kJ mole(-1), whereas catalase, in the absence of inhibitor, lowers the value to 11.2 kJ mole(-1), while in the presence 69 mmoles L(-1) of K2[B3O3F4OH] it was 37.8 kJ mole(-1).

  20. Amyloid-beta binds catalase with high affinity and inhibits hydrogen peroxide breakdown.

    OpenAIRE

    Milton, N G

    1999-01-01

    Amyloid-beta (Abeta) specifically bound purified catalase with high affinity and inhibited catalase breakdown of H(2)O(2). The Abeta-induced catalase inhibition involved formation of the inactive catalase Compound II and was reversible. CatalaseAbeta interactions provide rapid functional assays for the cytotoxic domain of Abeta and suggest a mechanism for some of the observed actions of Abeta plus catalase in vitro.

  1. Differential effects of catalase on apoptosis induction in human promonocytic cells. Relationships with heat-shock protein expression.

    Science.gov (United States)

    Sancho, Patricia; Troyano, Alfonso; Fernández, Carlos; De Blas, Elena; Aller, Patricio

    2003-03-01

    The administration of the H(2)O(2)-specific scavenger catalase attenuated the generation of apoptosis by the antitumor drugs etoposide, camptothecin, doxorubicin, and cisplatin in U-937 human promonocytic cells. By contrast, the antioxidant potentiated the generation of apoptosis by the inducers of the stress response, heat shock and cadmium, in this and other myeloid cell types. Catalase also increased the heat shock-provoked stimulation of caspase-3 and -9 activities, as well as the release of cytochrome c from mitochondria to the cytosol. The potentiation of cell death by catalase correlated with its capacity to inhibit the stress response, as demonstrated by the suppression of 70- or 27-kDa heat-shock protein expression and the inhibition of heat-shock transcription factor 1 binding activity. Conversely, the toxicity of catalase plus heat shock was attenuated when the cells were preconditioned with a soft heating, which elevated the 70-kDa heat-shock protein levels. By contrast with catalase, the antioxidants superoxide dismutase and probucol did not inhibit heat-shock protein expression or affect apoptosis in U-937 cells. Finally, it was observed that the antitumor drugs did not activate the stress response in U-937 cells and that catalase failed to inhibit HSP expression and to potentiate apoptosis in heat shock-treated RPMI 8866 lymphoblastic cells. Taken together, these results provide the first demonstration of a proapoptotic action of catalase, suggest that H(2)O(2) is a critical regulator of both apoptosis and the stress response, and corroborate the antiapoptotic action of heat-shock proteins in myeloid cells.

  2. A Laboratory Experiment of the Purification of Catalase.

    Science.gov (United States)

    Busquets, Montserrat; Franco, Rafael

    1986-01-01

    Describes a simple method for purifying catalase for the study of proteins. Procedures are systematically and diagramatically presented. Also identifies polyacrylamide gel electrophoresis, kinetic studies, and apparent molecular weight determination as possible techniques to be used in studying proteins. (ML)

  3. Purification and Properties of Catalase from Sweet Potato Root Microbodies

    OpenAIRE

    Muneharu, ESAKA; Tadashi, Asahi; Laboratory of Biochelnistry, Faculty of Agriculture, Nagoya University

    1982-01-01

    Catalase was isolated in a pure form from sweet potato root microbodies by simple procedures including ammonium sulfate fractionation and Sepharose 6B column chromatography. A single protein band was detected after polyacrylamide gel electrophoresis of the purified preparation. The catalase consisted of polypeptides with a molecular weight of 60,000 when analyzed by sodium dodecylsulfate-polyacrylamide gel electrophoresis, while the molecular weight of the enzyme was about 240,000 when estima...

  4. Overexpression of Catalase Enhances Benzo(a)pyrene Detoxification in Endothelial Microsomes.

    Science.gov (United States)

    Yang, Fang; Yang, Hong; Ramesh, Aramandla; Goodwin, J Shawn; Okoro, Emmanuel U; Guo, ZhongMao

    2016-01-01

    We previously reported that overexpression of catalase upregulated xenobiotic- metabolizing enzyme (XME) expression and diminished benzo(a)pyrene (BaP) intermediate accumulation in mouse aortic endothelial cells (MAECs). Endoplasmic reticulum (ER) is the most active organelle involved in BaP metabolism. To examine the involvement of ER in catalase-induced BaP detoxification, we compared the level and distribution of XMEs, and the profile of BaP intermediates in the microsomes of wild-type and catalase transgenic endothelial cells. Our data showed that endothelial microsomes were enriched in cytochrome P450 (CYP) 1A1, CYP1B1 and epoxide hydrolase 1 (EH1), and contained considerable levels of quinone oxidoreductase-1 (NQO1) and glutathione S-transferase-pi (GSTP). Treatment of wild-type MAECs with 1μM BaP for 2 h increased the expression of microsomal CYP1A1, 1B1 and NQO1 by ~300, 64 and 116%, respectively. However, the same treatment did not significantly alter the expression of EH1 and GSTP. Overexpression of catalase did not significantly increase EH1, but upregulated BaP-induced expression of microsomal CYP1A1, 1B1, NQO1 and GSTP in the following order: 1A1>NQO1>GSTP>1B1. Overexpression of catalase did not alter the distribution of each of these enzymes in the microsomes. In contrast to our previous report showing lower level of BaP phenols versus BaP diols/diones in the whole-cell, this report demonstrated that the sum of microsomal BaP phenolic metabolites were ~60% greater than that of the BaP diols/diones after exposure of microsomes to BaP. Overexpression of catalase reduced the concentrations of microsomal BaP phenols and diols/diones by ~45 and 95%, respectively. This process enhanced the ratio of BaP phenol versus diol/dione metabolites in a potent manner. Taken together, upregulation of phase II XMEs and CYP1 proteins, but not EH1 in the ER might be the mechanism by which overexpression of catalase reduces the levels of all the BaP metabolites, and

  5. Pseudomonas syringae Catalases Are Collectively Required for Plant Pathogenesis

    Science.gov (United States)

    Guo, Ming; Block, Anna; Bryan, Crystal D.; Becker, Donald F.

    2012-01-01

    The bacterial pathogen Pseudomonas syringae pv. tomato DC3000 must detoxify plant-produced hydrogen peroxide (H2O2) in order to survive in its host plant. Candidate enzymes for this detoxification include the monofunctional catalases KatB and KatE and the bifunctional catalase-peroxidase KatG of DC3000. This study shows that KatG is the major housekeeping catalase of DC3000 and provides protection against menadione-generated endogenous H2O2. In contrast, KatB rapidly and substantially accumulates in response to exogenous H2O2. Furthermore, KatB and KatG have nonredundant roles in detoxifying exogenous H2O2 and are required for full virulence of DC3000 in Arabidopsis thaliana. Therefore, the nonredundant ability of KatB and KatG to detoxify plant-produced H2O2 is essential for the bacteria to survive in plants. Indeed, a DC3000 catalase triple mutant is severely compromised in its ability to grow in planta, and its growth can be partially rescued by the expression of katB, katE, or katG. Interestingly, our data demonstrate that although KatB and KatG are the major catalases involved in the virulence of DC3000, KatE can also provide some protection in planta. Thus, our results indicate that these catalases are virulence factors for DC3000 and are collectively required for pathogenesis. PMID:22797762

  6. Improving of catalase stability properties by encapsulation in alginate/Fe3O4 magnetic composite beads for enzymatic removal of H2O2.

    Science.gov (United States)

    Doğaç, Yasemin Ispirli; Çinar, Mürvet; Teke, Mustafa

    2015-01-01

    The aim of this study was enhancing of stability properties of catalase enzyme by encapsulation in alginate/nanomagnetic beads. Amounts of carrier (10-100 mg) and enzyme concentrations (0.25-1.5 mg/mL) were analyzed to optimize immobilization conditions. Also, the optimum temperature (25-50°C), optimum pH (3.0-8.0), kinetic parameters, thermal stability (20-70°C), pH stability (4.0-9.0) operational stability (0-390 min), and reusability were investigated for characterization of the immobilized catalase system. The optimum pH levels of both free and immobilized catalase were 7.0. At the thermal stability studies, the magnetic catalase beads protected 90% activity, while free catalase maintained only 10% activity at 70°C. The thermal profile of magnetic catalase beads was spread over a large area. Similarly, this system indicated the improving of the pH stability. The reusability, which is especially important for industrial applications, was also determined. Thus, the activity analysis was done 50 times in succession. Catalase encapsulated magnetic alginate beads protected 83% activity after 50 cycles.

  7. Distribution of a Nocardia brasiliensis Catalase Gene Fragment in Members of the Genera Nocardia, Gordona, and Rhodococcus

    Science.gov (United States)

    Vera-Cabrera, Lucio; Johnson, Wendy M.; Welsh, Oliverio; Resendiz-Uresti, Francisco L.; Salinas-Carmona, Mario C.

    1999-01-01

    An immunodominant protein from Nocardia brasiliensis, P61, was subjected to amino-terminal and internal sequence analysis. Three sequences of 22, 17, and 38 residues, respectively, were obtained and compared with the protein database from GenBank by using the BLAST system. The sequences showed homology to some eukaryotic catalases and to a bromoperoxidase-catalase from Streptomyces violaceus. Its identity as a catalase was confirmed by analysis of its enzymatic activity on H2O2 and by a double-staining method on a nondenaturing polyacrylamide gel with 3,3′-diaminobenzidine and ferricyanide; the result showed only catalase activity, but no peroxidase. By using one of the internal amino acid sequences and a consensus catalase motif (VGNNTP), we were able to design a PCR assay that generated a 500-bp PCR product. The amplicon was analyzed, and the nucleotide sequence was compared to the GenBank database with the observation of high homology to other bacterial and eukaryotic catalases. A PCR assay based on this target sequence was performed with primers NB10 and NB11 to confirm the presence of the NB10-NB11 gene fragment in several N. brasiliensis strains isolated from mycetoma. The same assay was used to determine whether there were homologous sequences in several type strains from the genera Nocardia, Rhodococcus, Gordona, and Streptomyces. All of the N. brasiliensis strains presented a positive result but only some of the actinomycetes species tested were positive in the PCR assay. In order to confirm these findings, genomic DNA was subjected to Southern blot analysis. A 1.7-kbp band was observed in the N. brasiliensis strains, and bands of different molecular weight were observed in cross-reacting actinomycetes. Sequence analysis of the amplicons of selected actinomycetes showed high homology in this catalase fragment, thus demonstrating that this protein is highly conserved in this group of bacteria. PMID:10325357

  8. Antioxidant catalase rescues against high fat diet-induced cardiac dysfunction via an IKKβ-AMPK-dependent regulation of autophagy.

    Science.gov (United States)

    Liang, Lei; Shou, Xi-Ling; Zhao, Hai-Kang; Ren, Gu-Qun; Wang, Jian-Bang; Wang, Xi-Hui; Ai, Wen-Ting; Maris, Jackie R; Hueckstaedt, Lindsay K; Ma, Ai-Qun; Zhang, Yingmei

    2015-02-01

    Autophagy, a conservative degradation process for long-lived and damaged proteins, participates in a variety of biological processes including obesity. However, the precise mechanism of action behind obesity-induced changes in autophagy still remains elusive. This study was designed to examine the role of the antioxidant catalase in high fat diet-induced changes in cardiac geometry and function as well as the underlying mechanism of action involved with a focus on autophagy. Wild-type (WT) and transgenic mice with cardiac overexpression of catalase were fed low or high fat diet for 20 weeks prior to assessment of myocardial geometry and function. High fat diet intake triggered obesity, hyperinsulinemia, and hypertriglyceridemia, the effects of which were unaffected by catalase transgene. Myocardial geometry and function were compromised with fat diet intake as manifested by cardiac hypertrophy, enlarged left ventricular end systolic and diastolic diameters, fractional shortening, cardiomyocyte contractile capacity and intracellular Ca²⁺ mishandling, the effects of which were ameliorated by catalase. High fat diet intake promoted reactive oxygen species production and suppressed autophagy in the heart, the effects of which were attenuated by catalase. High fat diet intake dampened phosphorylation of inhibitor kappa B kinase β(IKKβ), AMP-activated protein kinase (AMPK) and tuberous sclerosis 2 (TSC2) while promoting phosphorylation of mTOR, the effects of which were ablated by catalase. In vitro study revealed that palmitic acid compromised cardiomyocyte autophagy and contractile function in a manner reminiscent of fat diet intake, the effect of which was significantly alleviated by inhibition of IKKβ, activation of AMPK and induction of autophagy. Taken together, our data revealed that the antioxidant catalase counteracts against high fat diet-induced cardiac geometric and functional anomalies possibly via an IKKβ-AMPK-dependent restoration of myocardial

  9. Docosahexaenoic acid inhibits IL-6 expression via PPARγ-mediated expression of catalase in cerulein-stimulated pancreatic acinar cells.

    Science.gov (United States)

    Song, Eun Ah; Lim, Joo Weon; Kim, Hyeyoung

    2017-07-01

    Cerulein pancreatitis mirrors human acute pancreatitis. In pancreatic acinar cells exposed to cerulein, reactive oxygen species (ROS) mediate inflammatory signaling by Janus kinase (JAK) 2/signal transducer and activator of transcription (STAT) 3, and cytokine induction. Docosahexaenoic acid (DHA) acts as an agonist of peroxisome proliferator activated receptor γ (PPARγ), which mediates the expression of some antioxidant enzymes. We hypothesized that DHA may induce PPARγ-target catalase expression and reduce ROS levels, leading to the inhibition of JAK2/STAT3 activation and IL-6 expression in cerulein-stimulated acinar cells. Pancreatic acinar AR42J cells were treated with DHA in the presence or absence of the PPARγ antagonist GW9662, or treated with the PPARγ agonist troglitazone, and then stimulated with cerulein. Expression of IL-6 and catalase, ROS levels, JAK2/STAT3 activation, and nuclear translocation of PPARγ were assessed. DHA suppressed the increase in ROS, JAK2/STAT3 activation, and IL-6 expression induced nuclear translocation of PPARγ and catalase expression in cerulein-stimulated AR42J cells. Troglitazone inhibited the cerulein-induced increase in ROS and IL-6 expression, but induced catalase expression similar to DHA in AR42J cells. GW9662 abolished the inhibitory effect of DHA on cerulein-induced increase in ROS and IL-6 expression in AR42J cells. DHA-induced expression of catalase was suppressed by GW9662 in cerulein-stimulated AR42J cells. Thus, DHA induces PPARγ activation and catalase expression, which inhibits ROS-mediated activation of JAK2/STAT3 and IL-6 expression in cerulein-stimulated pancreatic acinar cells. Copyright © 2017. Published by Elsevier Ltd.

  10. A Review on Direct Electrochemistry of Catalase for Electrochemical Sensors

    Directory of Open Access Journals (Sweden)

    Periasamy Arun Prakash

    2009-03-01

    Full Text Available Catalase (CAT is a heme enzyme with a Fe(III/II prosthetic group at its redox centre. CAT is present in almost all aerobic living organisms, where it catalyzes the disproportionation of H2O2 into oxygen and water without forming free radicals. In order to study this catalytic mechanism in detail, the direct electrochemistry of CAT has been investigated at various modified electrode surfaces with and without nanomaterials. The results show that CAT immobilized on nanomaterial modified electrodes shows excellent catalytic activity, high sensitivity and the lowest detection limit for H2O2 determination. In the presence of nanomaterials, the direct electron transfer between the heme group of the enzyme and the electrode surface improved significantly. Moreover, the immobilized CAT is highly biocompatible and remains extremely stable within the nanomaterial matrices. This review discusses about the versatile approaches carried out in CAT immobilization for direct electrochemistry and electrochemical sensor development aimed as efficient H2O2 determination. The benefits of immobilizing CAT in nanomaterial matrices have also been highlighted.

  11. N-glycosylation-negative catalase: a useful tool for exploring the role of hydrogen peroxide in the endoplasmic reticulum.

    Science.gov (United States)

    Lortz, S; Lenzen, S; Mehmeti, I

    2015-03-01

    Disulfide bond formation during protein folding of nascent proteins is associated with the generation of H2O2 in the endoplasmic reticulum (ER). Approaches to quantifying H2O2 directly within the ER failed because of the oxidative environment in the ER lumen, and ER-specific catalase expression to detoxify high H2O2 concentrations resulted in an inactive protein owing to N-glycosylation. Therefore, the N-glycosylation motifs at asparagine-244 and -439 of the human catalase protein were deleted by site-directed mutagenesis. The ER-targeted expression of these variants revealed that the deletion of the N-glycosylation motif only at asparagine-244 (N244) was associated with the maintenance of full enzymatic activity in the ER. Expression of catalase N244 in the ER (ER-Catalase N244) was ER-specific and protected the cells significantly against exogenously added H2O2. With the expression of ER-Catalase N244, a highly effective H2O2 inactivation within the ER was achieved for the first time. Catalase has a high H2O2-inactivation capacity without the need of reducing cofactors, which might interfere with the ER redox homeostasis, and is not involved in protein folding. With these characteristics ER-Catalase N244 is an ideal tool to explore the impact of ER-generated H2O2 on the generation of disulfide bonds or to study the induction of ER-stress pathways through protein folding overload and accumulation of H2O2. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. Cardiac-specific catalase overexpression rescues anthrax lethal toxin-induced cardiac contractile dysfunction: role of oxidative stress and autophagy

    Directory of Open Access Journals (Sweden)

    Kandadi Machender R

    2012-11-01

    Full Text Available Abstract Background Lethal and edema toxins secreted by Bacillus anthracis during anthrax infection were found to incite serious cardiovascular complications. However, the underlying mechanisms in anthrax lethal toxin-induced cardiac anomalies remain unknown. This study was designed to evaluate the impact of antioxidant enzyme catalase in anthrax lethal toxin-induced cardiomyocyte contractile dysfunction. Methods Wild type (WT and cardiac-specific catalase overexpression mice were challenged with lethal toxin (2 μg/g, intraperotineally (i.p.. Cardiomyocyte contractile and intracellular Ca2+ properties were assessed 18 h later using an IonOptix edge-detection system. Proteasome function was assessed using chymotrypsin-like and caspase-like activities. GFP-LC3 puncta and Western blot analysis were used to evaluate autophagy and protein ubiquitination. Results Lethal toxin exposure suppressed cardiomyocyte contractile function (suppressed peak shortening, maximal velocity of shortening/re-lengthening, prolonged duration of shortening/re-lengthening, and impaired intracellular Ca2+ handling, the effects of which were alleviated by catalase. In addition, lethal toxin triggered autophagy, mitochondrial and ubiquitin-proteasome defects, the effects of which were mitigated by catalase. Pretreatment of cardiomyocytes from catalase mice with the autophagy inducer rapamycin significantly attenuated or ablated catalase-offered protection against lethal toxin-induced cardiomyocyte dysfunction. On the other hand, the autophagy inhibitor 3-MA ablated or significantly attenuated lethal toxin-induced cardiomyocyte contractile anomalies. Conclusions Our results suggest that catalase is protective against anthrax lethal toxin-induced cardiomyocyte contractile and intracellular Ca2+ anomalies, possibly through regulation of autophagy and mitochondrial function.

  13. Catalase and alternative oxidase cooperatively regulate programmed cell death induced by beta-glucan elicitor in potato suspension cultures.

    Science.gov (United States)

    Mizuno, Masashi; Tada, Yasuomi; Uchii, Kimitaka; Kawakami, Sachiko; Mayama, Shigeyuki

    2005-04-01

    In potato (Solanum tuberosum L.) suspension cells, the expression of the gene encoding alternative oxidase (AOX) and H2O2 accumulation were induced by treatment with beta-glucan elicitor. The inhibition of catalase activity enhanced both AOX mRNA expression and the production of H2O2, whereas the ascorbate peroxidase inhibitor did not have any effect on these responses. Simultaneous inhibition of catalase and AOX activities in elicited cells dramatically increased H2O2 accumulation, leading to the disruption of mitochondrial membrane potential (deltapsi(m)) and programmed cell death (PCD). The results demonstrate, for the first time, that not only AOX but also catalase plays a central role in the suppression of mitochondrial deltapsi(m) breakdown and PCD induced by beta-glucan elicitor.

  14. Insight into the role of catalases in salt stress in potato (Solanum tuberosum L.

    Directory of Open Access Journals (Sweden)

    M'Hamdi M.

    2009-01-01

    Full Text Available In order to investigate a possible link between catalase (CAT activity and salinity tolerance, an in vitro and in vivo study of the behavior of transgenic lines of potato (cv. ‘Désirée’ under salt stress conditions was carried out. Three groups of transgenic lines and non transformed control (DWT were used in this study: lines expressing a bacterial catalase gene and lines repressing catalase activity by either co-suppression or anti-sense strategies. Various concentrations of NaCl were tested: in vitro 0, 25, 50 and 75 mM and in vivo 25, 50 and 75 mM. The results of this work show that the genetic modification of CAT activity affects the multiplication rate of vitroplants, as well as vegetative and physiological growth parameters under salt stress conditions. At 25, 50 and 75 mM of NaCl, over-expression (line KatE16 and repression of CAT increased and reduced respectively the multiplication rate of vitroplants. Differences between the transgenic lines and the wild type were evident in tuber yield and leaf chlorophyll content. These parameters were significantly increased in CAT over-expressing and slightly decreased in SU3 line repressed in CAT under 25 mM of salt stress. A stability of the potential quantum yield (Fv/Fm was observed in the lines over-expressing the CAT at 25, 50 and 75 mM of NaCl. The repression of CAT was associated with a decrease of Fv/Fm value at 50 mM of NaCl. These results show that catalases contribute to salinity tolerance mechanisms in potato.

  15. Molecular identification and characterisation of catalase and catalase-like protein genes in urease-positive thermophilic Campylobacter (UPTC).

    Science.gov (United States)

    Nakajima, T; Kuribayashi, T; Moore, J E; Millar, B C; Yamamoto, S; Matsuda, Motoo

    2016-01-01

    Thermophilic Campylobacter are important bacterial pathogens of foodborne diseases worldwide. These organisms' physiology requires a microaerophilic atmosphere. To date, little is known about the protective catalase mechanism in urease-positive thermophilic campylobacters (UPTC); hence, it was the aim of this study to identify and characterise catalase and catalase-like protein genes in these organisms. Catalase (katA) and catalase (Kat)-like protein genes from the Japanese UPTC CF89-12 strain were molecularly analysed and compared with C. lari RM2100 and other C. lari and thermophilic Campylobacter reference isolates. A possible open reading frame of 1,422 base pairs, predicted to encode a peptide of 474 amino acid residues, with calculated molecular weight of 52.7 kilo Daltons for katA, was identified within UPTC CF89-12. A probable ribosome binding site, two putative promoters and a putative ρ-independent transcription terminator were also identified within katA. A similar katA cluster also existed in the C. lari RM2100 strain, except that this strain carries no DcuB genes. However, the Kat-like protein gene or any other homologue(s) were never identified in the C. lari RM2100 strain, or in C. jejuni and C. upsaliensis. This study demonstrates the presence of catalase/catalase-like protein genes in UPTC organisms. These findings are significant in that they suggest that UPTC organisms have the protective genetic capability of helping protect the organisms from toxic oxygen stress, which may help them to survive in physiologically harsh environments, both within human and animal hosts, as well as in the natural environment.

  16. Metformin affects macrophages' phenotype and improves the activity of glutathione peroxidase, superoxide dismutase, catalase and decreases malondialdehyde concentration in a partially AMPK-independent manner in LPS-stimulated human monocytes/macrophages.

    Science.gov (United States)

    Bułdak, Łukasz; Łabuzek, Krzysztof; Bułdak, Rafał Jakub; Kozłowski, Michał; Machnik, Grzegorz; Liber, Sebastian; Suchy, Dariusz; Duława-Bułdak, Anna; Okopień, Bogusław

    2014-06-01

    Diabetic patients experience accelerated atherosclerosis. Metformin is a cornerstone of the current therapy of type 2 diabetes. Macrophages are the key cells associated with the development of atherosclerotic plaques. Therefore, our aim was to assess the in vitro effects of metformin on macrophages and its influence on the mechanisms involved in the development of atherosclerosis. Peripheral blood mononuclear cells were obtained from the group including 16 age-matched healthy non-smoking volunteers aged 18-40 years. Monocytes were further incubated with metformin, LPS and compound C--a pharmacological inhibitor of AMPK. The impact of metformin on oxidative stress markers, antioxidative properties, inflammatory cytokines and phenotypical markers of macrophages was studied. We showed that macrophages treated with metformin expressed less reactive oxygen species (ROS), which resulted from increased antioxidative potential. Furthermore, a reduction in inflammatory cytokines was observed. We also observed a phenotypic shift toward the alternative activation of macrophages that was induced by metformin. All the aforementioned results resulted from AMPK activation, but a residual activity of metformin after AMPK blockade was still noticeable even after inhibition of AMPK by compound C. Authors believe that metformin-based therapy, a cornerstone in diabetes therapy, not only improves the prognosis of diabetics by reducing blood glucose but also by reducing oxidative stress, inflammatory cytokine production and the shift toward alternative activation of macrophages. Copyright © 2014 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  17. Catalase-Negative Staphylococcus lugdunensis Strain with a Novel Point Mutation in the Catalase Gene Isolated from a Patient with Chronic Suppurative Otitis Media

    OpenAIRE

    Lu, Yong; Wang, Yiping; Ling, Buzhi; Xianfu KE; Ying, Jianfei; Yu, Yanhong; He, Mingyang; Li, Xiangyang

    2013-01-01

    This report describes the results of the sequence analysis of a methicillin-susceptible strain of catalase-negative Staphylococcus lugdunensis. Molecular characterization of the deduced sequence revealed a novel point mutation in the catalase gene. To our knowledge, this is the first report of a catalase-negative S. lugdunensis strain, although catalase-negative isolates of Staphylococcus aureus and Staphylococcus epidermidis have been previously reported.

  18. Lower Serum Catalase Level is Associated with Preterm Labor among Pregnant Women at Sanglah Hospital Denpasar, Bali-Indonesia

    Directory of Open Access Journals (Sweden)

    I Ketut Surya Negara

    2016-09-01

    Full Text Available Background: Preterm labor is still become a serious health problem in Obstetric and Perinatology with no sensitive biomarker currently approved. Several studies show that decrease antioxidant activity may play significant role in preterm labor. However, only few studies had been conducted to evaluate blood catalase level in preterm labor and assess its role in preterm labor. Objective: The aim this study was to identify the differences of maternal serum catalase level in preterm labor compared with preterm pregnancy. Methods: An observational analytic cross sectional study was conducted from February to December 2014 using pregnant women with 28-36 weeks’ gestational age. Blood catalase level was evaluated by colorimetric method and the data was analyzed by SPPS for Windows 17.0 program. Results: 12 subjects were enrolled and divided into preterm and control group. No significant differences between mean age, gestational age, and parity between preterm and control group. However, blood catalase level was significantly lower in preterm group compared with control group (81.82 ± 20.38 vs 159.38 ± 35.79; p=0.001. Conclusion: Serum maternal catalase level were significantly lower in preterm labor compared with preterm normal pregnancy.

  19. IDENTIFICATION AND CHARACTERIZATION OF THE CATALASE GENE PyCAT FROM THE RED ALGA PYROPIA YEZOENSIS (BANGIALES, RHODOPHYTA)(1).

    Science.gov (United States)

    Li, Xian C; Xing, Yong Z; Jiang, Xue; Qiao, Jing; Tan, Hai L; Tian, Yu; Zhou, Bin

    2012-06-01

    Catalase is an antioxidant enzyme that plays a significant role in protection against oxidative stress by reducing hydrogen peroxide. The full-length catalase cDNA sequence as isolated from expressed sequence tags (ESTs) of Pyropia yezoensis (Ueda) M. S. Hwang et H. G. Choi (PyCAT) through rapid amplification of cDNA ends (RACE) was identified and characterized. It encoded a polypeptide of 529 amino acids, which shared 36%-44% similarity with other known catalase proteins. Phylogenetic analysis revealed that PyCAT was closer to the catalases from plants than from other organisms. The PyCAT mRNA expression was investigated using real-time PCR to determine life-cycle-specific expression and the expression pattern during desiccation. The mRNA expression level in gametophytes was significantly higher than in sporophytes, and the mRNA expression level of PyCAT was significantly up-regulated during the desiccation process. The recombinant PyCAT protein was purified and analyzed biochemically. The recombinant PyCAT protein exhibited high enzymatic activity (28,000 U·mg(-1) ) with high thermal stability and a broad pH range. All these results indicate that the PyCAT is a typical member of the plant and algal catalase family and may play a significant role in minimizing the effect of oxidative damage in P. yezoensis during desiccation. © 2012 Phycological Society of America.

  20. Spectroscopy, calorimetry and molecular simulation studies on the interaction of catalase with copper ion.

    Science.gov (United States)

    Hao, Fang; Jing, Mingyang; Zhao, Xingchen; Liu, Rutao

    2015-02-01

    In this research, the binding mechanism of Cu(2+) to bovine liver catalase (BLC) was studied by fluorescence spectroscopy, ultraviolet-visible (UV-vis) absorption spectroscopy, circular dichroism (CD) spectroscopy, isothermal titration calorimetry (ITC) and molecular docking methods. The cellar experiment was firstly carried out to investigate the inhibition effect of catalase. During the fluorescence quenching study, after correcting the inner filter effect (IFE), the fluorescence of BLC was found to be quenched by Cu(2+). The quenching mechanism was determined by fluorescence lifetime measurement, and was confirmed to be the dynamic mode. The secondary structure content of BLC was changed by the addition of Cu(2+), as revealed by UV-vis absorption and CD spectra, which further induces the decrease in BLC activity. Molecular simulation study indicates that Cu(2+) is located between two β-sheets and two random coils of BLC near to the heme group, and interacts with His 74 and Ser 113 residues near a hydrophilic area. The decrease of α-helix and the binding of His 74 are considered to be the major reason for the inhibition of BLC activity caused by Cu(2+). The ITC results indicate that the binding stoichiometry of Cu(2+) to catalase is 11.4. Moreover, the binding of Cu(2+) to BLC destroyed H-bonds, which was confirmed by the CD result. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Catalase in Leishmaniinae: With me or against me?

    Science.gov (United States)

    Kraeva, Natalya; Horáková, Eva; Kostygov, Alexei Y; Kořený, Luděk; Butenko, Anzhelika; Yurchenko, Vyacheslav; Lukeš, Julius

    2017-06-01

    The catalase gene is a virtually ubiquitous component of the eukaryotic genomes. It is also present in the monoxenous (i.e. parasitizing solely insects) trypanosomatids of the subfamily Leishmaniinae, which have acquired the enzyme by horizontal gene transfer from a bacterium. However, as shown here, the catalase gene was secondarily lost from the genomes of all Leishmania sequenced so far. Due to the potentially key regulatory role of hydrogen peroxide in the inter-stagial transformation of Leishmania spp., this loss seems to be a necessary prerequisite for the emergence of a complex life cycle of these important human pathogens. Hence, in this group of protists, the advantages of keeping catalase were uniquely outweighed by its disadvantages. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Relación entre la frecuencia fundamental propia de una tabla de Iroko (Clorophora excelsa) y sus dimensiones . Aplicación a la txalaparta

    OpenAIRE

    Gambra Uriz, Anai

    2009-01-01

    Estudi científic sobre l’acústica d’una taula doblement recolzada i la seva aplicació a la txalaparta. Després d’un experiment destructor amb Iroko (Clorophora excelsa) es va trobar la relació matemàtica que definia la freqüència fonamental pròpia d’una taula en funció de la seva pròpia longitud. Es van estudiar els principis acústics que definien el so de la txalaparta a demés de proposar un model de txalaparta afinada basat en les relacions obtingudes. S’estableixen unes bases d’experiment...

  3. Catalase protects Aedes aegypti from oxidative stress and increases midgut infection prevalence of Dengue but not Zika.

    Science.gov (United States)

    Oliveira, José Henrique M; Talyuli, Octávio A C; Goncalves, Renata L S; Paiva-Silva, Gabriela Oliveira; Sorgine, Marcos Henrique F; Alvarenga, Patricia Hessab; Oliveira, Pedro L

    2017-04-01

    Digestion of blood in the midgut of Aedes aegypti results in the release of pro-oxidant molecules that can be toxic to the mosquito. We hypothesized that after a blood meal, the antioxidant capacity of the midgut is increased to protect cells against oxidative stress. Concomitantly, pathogens present in the blood ingested by mosquitoes, such as the arboviruses Dengue and Zika, also have to overcome the same oxidative challenge, and the antioxidant program induced by the insect is likely to influence infection status of the mosquito and its vectorial competence. We found that blood-induced catalase mRNA and activity in the midgut peaked 24 h after feeding and returned to basal levels after the completion of digestion. RNAi-mediated silencing of catalase (AAEL013407-RB) reduced enzyme activity in the midgut epithelia, increased H2O2 leakage and decreased fecundity and lifespan when mosquitoes were fed H2O2. When infected with Dengue 4 and Zika virus, catalase-silenced mosquitoes showed no alteration in infection intensity (number of plaque forming units/midgut) 7 days after the infectious meal. However, catalase knockdown reduced Dengue 4, but not Zika, infection prevalence (percent of infected midguts). Here, we showed that blood ingestion triggers an antioxidant response in the midgut through the induction of catalase. This protection facilitates the establishment of Dengue virus in the midgut. Importantly, this mechanism appears to be specific for Dengue because catalase silencing did not change Zika virus prevalence. In summary, our data suggest that redox balance in the midgut modulates mosquito vectorial competence to arboviral infections.

  4. Heterosis for superoxide dismutase, peroxidase and catalase ...

    Indian Academy of Sciences (India)

    and the direction of heterosis for SOD, POX and CAT activ- ity; and identify promising parents and single cross-hybrids. (SCHs) having better inbuilt defense systems which could be used for breeding antioxidant-rich cabbage. Materials and methods. Sixteen cabbage genotypes (all inbreds) which included five female, viz.

  5. Studies to reveal the nature of interactions between catalase and curcumin using computational methods and optical techniques.

    Science.gov (United States)

    Mofidi Najjar, Fayezeh; Ghadari, Rahim; Yousefi, Reza; Safari, Naser; Sheikhhasani, Vahid; Sheibani, Nader; Moosavi-Movahedi, Ali Akbar

    2017-02-01

    Curcumin is an important antioxidant compound, and is widely reported as an effective component for reducing complications of many diseases. However, the detailed mechanisms of its activity remain poorly understood. We found that curcumin can significantly increase catalase activity of BLC (bovine liver catalase). The mechanism of curcumin action was investigated using a computational method. We suggested that curcumin may activate BLC by modifying the bottleneck of its narrow channel. The molecular dynamic simulation data showed that placing curcumin on the structure of enzyme can increase the size of the bottleneck in the narrow channel of BLC, and readily allow the access of substrate to the active site. Because of the increase of the distance between amino acids of the bottleneck in the presence of curcumin, the entrance space of substrate increased from 250Å3 to 440Å3. In addition, the increase in emission of intrinsic fluorescence of BLC in presence of curcumin demonstrated changes in tertiary structure of catalase, and possibility of less quenching. We also used circular dichroism (CD) spectropolarimetry to determine how curcumin may alter the enzyme secondary structure. Catalase spectra in the presence of various concentrations of curcumin showed an increase in the amount of α-helix content. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Juniperus excelsa Bieb.

    African Journals Online (AJOL)

    USER

    2010-04-05

    Apr 5, 2010 ... the best quality in terms of the measured criteria can be grown in 11 cm x 30 cm pots. In respect to the .... statistical model used in comparison of tested pot lengths and growth media is ..... Multi-criteria analysis for locating new.

  7. Trinuclear manganese complexes of unsymmetrical polypodal diamino N3O3 ligands with an unusual [Mn3(μ-OR)4]5+ triangular core: synthesis, characterization, and catalase activity.

    Science.gov (United States)

    Ledesma, Gabriela N; Anxolabéhère-Mallart, Elodie; Rivière, Eric; Mallet-Ladeira, Sonia; Hureau, Christelle; Signorella, Sandra R

    2014-03-03

    Two new tri-Mn(III) complexes of general formula [Mn3L2(μ-OH)(OAc)]ClO4 (H3L = 1-[N-(2-pyridylmethyl),N-(2-hydroxybenzyl)amino]-3-[N'-(2-hydroxybenzyl),N'-(4-X-benzyl)amino]propan-2-ol; 1ClO4, X = Me; 2ClO4, X = H) have been prepared and characterized. X-ray diffraction analysis of 1ClO4 reveals that the complex cation possesses a Mn3(μ-alkoxo)2(μ-hydroxo)(μ-phenoxo)(4+) core, with the three Mn atoms bound to two fully deprotonated N3O3 chelating L(3-), one exogenous acetato ligand, and one hydroxo bridge, the structure of which is retained upon dissolution in acetonitrile or methanol. The three Mn atoms occupy the vertices of a nearly isosceles triangle (Mn1···Mn3 = 3.6374(12) Å, Mn2···Mn3 3.5583(13) Å, and Mn1···Mn2 3.2400(12) Å), with one substitution-labile site on the apical Mn ion occupied by terminally bound monodentate acetate. Temperature-dependent magnetic susceptibility studies indicate the presence of predominant antiferromagnetic intramolecular interactions between Mn(III) ions in 1ClO4. Complexes 1ClO4 and 2ClO4 decompose H2O2 at comparable rates upon initial binding of peroxide through acetate substitution, with retention of core structure during catalysis. Kinetic and spectroscopic studies suggest that these complexes employ the [Mn-(μ-oxo/aquo)-Mn](4+) moiety to activate peroxide, with the additional (μ-alkoxo)(μ-phenoxo)Mn(μ-alkoxo) metallobridge carrying out a structural function.

  8. Catalase epitopes vaccine design for Helicobacter pylori: A ...

    African Journals Online (AJOL)

    Jane

    2011-08-15

    Aug 15, 2011 ... Among predicted epitopes, three epitopes were selected including, MVNKDVKQTT, VLLQSTWFL and FHPFDVTKI. Three candidates out of 51catalase antigen epitopes had the highest score for reactivating with MHC II MHC in propred software. The candidate epitopes for vaccine design should be rather a ...

  9. Catalase epitopes vaccine design for Helicobacter pylori : A ...

    African Journals Online (AJOL)

    Three candidates out of 51catalase antigen epitopes had the highest score for reactivating with MHC II MHC in propred software. The candidate epitopes for vaccine design should be rather a composition of considering epitopes: MVNKDVKQTTKKVLLQSTWFLKKFHPFDVTKI. In this manner, 39 of 51 alleles of MHC class ІІ ...

  10. Catalase in Leishmaniinae: With me or against me?

    Czech Academy of Sciences Publication Activity Database

    Kraeva, N.; Horáková, Eva; Kostygov, A.Y.; Kořený, Luděk; Butenko, A.; Yurchenko, V.; Lukeš, Julius

    2017-01-01

    Roč. 50, JUN (2017), s. 121-127 ISSN 1567-1348 R&D Projects: GA ČR(CZ) GA16-18699S Institutional support: RVO:60077344 Keywords : Catalase * Leishmania * Trypanosomatids * Gene loss Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.885, year: 2016

  11. The nature of plant growth-promoting effects of a pseudoalteromonad associated with the marine algae Laminaria japonica and linked to catalase excretion.

    Science.gov (United States)

    Dimitrieva, G Y; Crawford, R L; Yüksel, G U

    2006-05-01

    The goal of this study was to identify a marine algae-associated bacterium isolated from Laminaria japonica and investigate this microorganism's growth-promoting effects on plants. The bacterium, identified as Pseudoalteromonas porphyrae, was determined to display a biostimulatory activity for seed germination and shoot growth in several agricultural plants and also for growth in ginseng callus cell culture. This biostimulatory activity was linked to a catalase enzyme that was excreted in the maximal amount during the transition from logarithmic growth phase to stationary growth phase. In addition, selected shifts in growth temperature and medium salinity affected the amount of enzyme excreted. The purified catalase was determined to be composed of identical subunits. The catalase of interest displayed significantly higher biostimulatory activity than the catalase from bovine liver. The catalase investigated in this study is unique in that it promotes growth in and possibly contributes to stress tolerance of plants. The catalase of interest has the potential for use in treatments that aim to improve percent seed germination as well as obtaining tall shoots in a shorter time period.

  12. Catalase activity in healthy and inflamed pulp tissues of permanent ...

    African Journals Online (AJOL)

    2015-11-02

    Nov 2, 2015 ... Erzurum 25240, Erzurum, Turkey. E‑mail: damla.ozsu@hotmail.com. Introduction. Many cell ... Atatürk University Dentistry Faculty, Erzurum, Turkey. The patients included had to comply with the ... grooved with a fissure bur and then split in half with cutting pliers to extirpate of pulp specimens. The inflamed ...

  13. Efficacy of cryotherapy plus topical Juniperus excelsa M. Bieb cream versus cryotherapy plus placebo in the treatment of Old World cutaneous leishmaniasis: A triple-blind randomized controlled clinical trial.

    Science.gov (United States)

    Parvizi, Mohammad Mahdi; Handjani, Farhad; Moein, Mahmoodreza; Hatam, Gholamreza; Nimrouzi, Majid; Hassanzadeh, Jafar; Hamidizadeh, Nasrin; Khorrami, Hamid Reza; Zarshenas, Mohammad Mehdi

    2017-10-01

    Cutaneous leishmaniasis is one of the highly prevalent endemic diseases in the Middle East and North Africa. Many treatment modalities have been recommended for this condition but success rates remain limited. Herbal remedies have also been used for treatment but evidence-based clinical trials with these products are sparse. In-vitro and in-vivo studies have shown the anti-leishmanial and curative effects of extract of fruits and leaves of Juniperus excelsa (J. excelsa). The aim of this study was to determine the efficacy of topical J. excelsa M. Bieb extract as an adjuvant to cryotherapy for the treatment of human CL. This study was designed as a two-arm triple-blind randomized placebo-controlled clinical trial using a parallel design. Seventy-two patients with clinical diagnosis of CL confirmed by leishmania smears were allocated to receive either a topical formulation of leaf of J. excelsa extract (group A) or placebo (group B) for 3 months. Both groups received cryotherapy as baseline standard treatment. Patients were evaluated before and weekly after the intervention was initiated until complete cure. Overall, 82% of patients in group A, experienced complete cure and 9% of them had partial cure. On the other hand, 34% in group B reported complete cure, while 14% of them had partial cure at the end of treatment protocol with a significant difference between the two groups (Pcryotherapy for accelerating the time to cure in addition to increasing the complete cure rate in CL. ClinicalTrials.gov IRCT2015082523753N1.

  14. Structure of catalase determined by MicroED

    Science.gov (United States)

    Nannenga, Brent L; Shi, Dan; Hattne, Johan; Reyes, Francis E; Gonen, Tamir

    2014-01-01

    MicroED is a recently developed method that uses electron diffraction for structure determination from very small three-dimensional crystals of biological material. Previously we used a series of still diffraction patterns to determine the structure of lysozyme at 2.9 Å resolution with MicroED (Shi et al., 2013). Here we present the structure of bovine liver catalase determined from a single crystal at 3.2 Å resolution by MicroED. The data were collected by continuous rotation of the sample under constant exposure and were processed and refined using standard programs for X-ray crystallography. The ability of MicroED to determine the structure of bovine liver catalase, a protein that has long resisted atomic analysis by traditional electron crystallography, demonstrates the potential of this method for structure determination. DOI: http://dx.doi.org/10.7554/eLife.03600.001 PMID:25303172

  15. X-ray diffraction study of Penicillium Vitale catalase in the complex with aminotriazole

    Energy Technology Data Exchange (ETDEWEB)

    Borovik, A. A.; Grebenko, A. I.; Melik-Adamyan, V. R., E-mail: mawr@ns.crys.ras.ru [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)

    2011-07-15

    The three-dimensional structure of the enzyme catalase from Penicillium vitale in a complex with the inhibitor aminotriazole was solved and refined by protein X-ray crystallography methods. An analysis of the three-dimensional structure of the complex showed that the inhibition of the enzyme occurs as a result of the covalent binding of aminotriazole to the amino-acid residue His64 in the active site of the enzyme. An investigation of the three-dimensional structure of the complex resulted in the amino-acid residues being more precisely identified. The binding sites of saccharide residues and calcium ions in the protein molecule were found.

  16. Isonicotinic Acid Hydrazide Conversion to Isonicotinyl-NAD by Catalase-peroxidases*

    OpenAIRE

    Wiseman, Ben; Carpena, Xavi; Feliz, Miguel; Donald, Lynda J.; Pons, Miquel; Fita, Ignacio; Loewen, Peter C

    2010-01-01

    Activation of the pro-drug isoniazid (INH) as an anti-tubercular drug in Mycobacterium tuberculosis involves its conversion to isonicotinyl-NAD, a reaction that requires the catalase-peroxidase KatG. This report shows that the reaction proceeds in the absence of KatG at a slow rate in a mixture of INH, NAD+, Mn2+, and O2, and that the inclusion of KatG increases the rate by >7 times. Superoxide, generated by either Mn2+- or KatG-catalyzed reduction of O2, is an essential intermediate in the r...

  17. Overexpression of Catalase Diminishes Oxidative Cysteine Modifications of Cardiac Proteins.

    Directory of Open Access Journals (Sweden)

    Chunxiang Yao

    Full Text Available Reactive protein cysteine thiolates are instrumental in redox regulation. Oxidants, such as hydrogen peroxide (H2O2, react with thiolates to form oxidative post-translational modifications, enabling physiological redox signaling. Cardiac disease and aging are associated with oxidative stress which can impair redox signaling by altering essential cysteine thiolates. We previously found that cardiac-specific overexpression of catalase (Cat, an enzyme that detoxifies excess H2O2, protected from oxidative stress and delayed cardiac aging in mice. Using redox proteomics and systems biology, we sought to identify the cysteines that could play a key role in cardiac disease and aging. With a 'Tandem Mass Tag' (TMT labeling strategy and mass spectrometry, we investigated differential reversible cysteine oxidation in the cardiac proteome of wild type and Cat transgenic (Tg mice. Reversible cysteine oxidation was measured as thiol occupancy, the ratio of total available versus reversibly oxidized cysteine thiols. Catalase overexpression globally decreased thiol occupancy by ≥1.3 fold in 82 proteins, including numerous mitochondrial and contractile proteins. Systems biology analysis assigned the majority of proteins with differentially modified thiols in Cat Tg mice to pathways of aging and cardiac disease, including cellular stress response, proteostasis, and apoptosis. In addition, Cat Tg mice exhibited diminished protein glutathione adducts and decreased H2O2 production from mitochondrial complex I and II, suggesting improved function of cardiac mitochondria. In conclusion, our data suggest that catalase may alleviate cardiac disease and aging by moderating global protein cysteine thiol oxidation.

  18. The relevance of the non-canonical PTS1 of peroxisomal catalase

    NARCIS (Netherlands)

    Williams, Chris; Aksam, Eda Bener; Gunkel, Katja; Veenhuis, Marten; van der Klei, Ida J.

    Catalase is sorted to peroxisomes via a C-terminal peroxisomal targeting signal 1 (PTS1), which binds to the receptor protein Pex5. Analysis of the C-terminal sequences of peroxisomal catalases from various species indicated that catalase never contains the typical C-terminal PTS1 tripeptide-SKL,

  19. Rapid catalase supplemental test for identification of members of the family Enterobacteriaceae.

    OpenAIRE

    Chester, B; Moskowitz, L B

    1987-01-01

    A simple, rapid, semiquantitative slide catalase test useful for differentiating members of the family Enterobacteriaceae is described. Judging by the time required for appearance of oxygen bubbles in 3% hydrogen peroxide, the immediate catalase reactors were Yersinia, Serratia, Proteus, Morganella, Providencia, Cedecea, and Hafnia spp. The delayed catalase reactors were Escherichia, Shigella, Klebsiella, Enterobacter, Salmonella, Citrobacter, Edwardsiella, Kluyvera, and Tatumella spp. This i...

  20. The effect of deep eutectic solvents on catalytic function and structure of bovine liver catalase.

    Science.gov (United States)

    Harifi-Mood, Ali Reza; Ghobadi, Roohollah; Divsalar, Adeleh

    2017-02-01

    Aqueous solutions of reline and glyceline, the most common deep eutectic solvents, were used as a medium for Catalase reaction. By some spectroscopic methods such as UV-vis, fluorescence and circular dichroism (CD) function and structure of Catalase were investigated in aqueous solutions of reline and glyceline. These studies showed that the binding affinity of the substrate to the enzyme increased in the presence of 100mM glyceline solution, which contrasts with reline solution that probably relates to instructive changes in secondary structure of protein. Meanwhile, enzyme remained nearly 70% and 80% active in this concentration of glyceline and reline solutions respectively. In the high concentration of DES solutions, enzyme became mainly inactive but surprisingly stayed in nearly 40% active in choline chloride solution, which is the common ion species in reline and glyceline solvents. It is proposed that the chaotropic nature of choline cation might stop the reducing trend of activity in concentrated choline chloride solutions but this instructive effect is lost in aqueous deep eutectic solvents. In this regard, the presence of various concentrations of deep eutectic solvents in the aqueous media of human cells would be an activity adjuster for this important enzyme in its different operation conditions. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. The use of glucose oxidase and catalase for the enzymatic reduction of the potential ethanol content in wine.

    Science.gov (United States)

    Röcker, Jessica; Schmitt, Matthias; Pasch, Ludwig; Ebert, Kristin; Grossmann, Manfred

    2016-11-01

    Due to the increase of sugar levels in wine grapes as one of the impacts of climate change, alcohol reduction in wines becomes a major focus of interest. This study combines the use of glucose oxidase and catalase activities with the aim of rapid conversion of glucose into non-fermentable gluconic acid. The H2O2 hydrolysing activity of purified catalase is necessary in order to stabilize glucose oxidase activity. After establishing the adequate enzyme ratio, the procedure was applied in large-scale trials (16L- and 220L-scale) of which one was conducted in a winery under industrial wine making conditions. Both enzyme activity and wine flavour were clearly influenced by the obligatory aeration in the different trials. With the enzyme treatment an alcohol reduction of 2%vol. was achieved after 30h of aeration. However the enzyme treated wines were significantly more acidic and less typical. Copyright © 2016. Published by Elsevier Ltd.

  2. Novel immobilization process of a thermophilic catalase: efficient purification by heat treatment and subsequent immobilization at high temperature.

    Science.gov (United States)

    Xu, Juan; Luo, Hui; López, Claudia; Xiao, Jing; Chang, Yanhong

    2015-10-01

    The main goal of the present work is to investigate a novel process of purification and immobilization of a thermophilic catalase at high temperatures. The catalase, originated from Bacillus sp., was overexpressed in a recombinant Escherichia coli BL21(DE3)/pET28-CATHis and efficiently purified by heat treatment, achieving a threefold purification. The purified catalase was then immobilized onto an epoxy support at different temperatures (25, 40, and 55 °C). The immobilizate obtained at higher temperatures reached its maximum activity in a shorter time than that obtained at lower temperatures. Furthermore, immobilization at higher temperatures required a lower ionic strength than immobilization at lower temperatures. The characteristics of immobilized enzymes prepared at different temperatures were investigated. The high-temperature immobilizate (55 °C) showed the highest thermal stability, followed by the 40 °C immobilizate. And the high-temperature immobilizate (55 °C) had slightly higher operational stability than the 25 °C immobilizate. All of the immobilized catalase preparations showed higher stability than the free enzyme at alkaline pH 10.0, while the alkali resistance of the 25 °C immobilizate was slightly better than that of the 40 and 55 °C immobilizates.

  3. Antioxidant Activity of Leaves and Fruits of Iranian Conifers

    Directory of Open Access Journals (Sweden)

    S. A. Emami

    2007-01-01

    Full Text Available Cupressus semipervirens var. horizontalis, Cupressus semipervirens var. semipervirens, Cupressus semipervirens cv. Cereifeormis, Juniperus communis subsp. hemisphaerica, Juniperus excelsa subsp. excelsa, Juniperus excelsa subsp. polycarpos, Juniperus foetidissima, Juniperus oblonga, Juniperus sabina, Platycladus orientalis and Taxus baccata are Iranian conifers. The antioxidant activity of leaves and fruits of these 11 different taxons were evaluated. The leaves of both male and female, and fruits of these plants were collected from different areas of the country. Methanol extract of leaves and fruits of these taxons were prepared. Antioxidant activity of each extracts was measured using two different tests of the ferric thiocyanate method and thiobarbituric acid. Results indicated that the methanol extracts of leaves, of male and female, and fruits of all these species (27 samples possessed antioxidant activity when tested with both methods. The antioxidant activity was then compared with those of α-tocopherol (a natural antioxidant and butylated hydroxytoluene (a synthetic antioxidant. Methanol extract of fruits of C. semipervirens cv. Cereifeormis showed the highest antioxidant activity while the methanol extract of leaves of C. semipervirens var. semipervirens possessed the lowest antioxidant activity. However, our finding showed that most of the tested extracts were showing strong antioxidant activity even higher than α-tocopherol.

  4. [Fermentation production of microbial catalase and its application in textile industry].

    Science.gov (United States)

    Zhang, Dongxu; Du, Guocheng; Chen, Jian

    2010-11-01

    Microbial catalase is an important industrial enzyme that catalyzes the decomposition of hydrogen peroxide to water and oxygen. This enzyme has great potential of application in food, textile and pharmaceutical industries. The production of microbial catalase has been significantly improved thanks to advances in bioprocess engineering and genetic engineering. In this paper, we review the progresses in fermentation production of microbial catalase and its application in textile industry. Among these progresses, we will highlight strain isolation, substrate and environment optimization, enzyme induction, construction of engineering strains and application process optimization. Meanwhile, we also address future research trends for microbial catalase production and its application in textile industry. Molecular modification (site-directed mutagenesis and directed revolution) will endue catalase with high pH and temperature stabilities. Improvement of catalase production, based on the understanding of induction mechanism and the process control of recombinant stain fermentation, will further accelerate the application of catalase in textile industry.

  5. Sobrevivência e Frutificação de Bertholletia excelsa Bonpl. em Áreas Desmatadas em Oriximiná, Pará

    Directory of Open Access Journals (Sweden)

    Ricardo Scoles

    Full Text Available RESUMO Analisaram-se as condições biológicas (sobrevivência, reprodução, rebrotação e estrutura de populações de castanheira (Bertholletia excelsa Bonpl. nas margens de estradas em áreas desmatadas (Oriximiná, Pará. Identificaram-se 441 árvores de castanheira (Diâmetro à Altura do Peito – DAP > 10 cm. De cada árvore, coletaram-se as coordenadas geográficas, dados dendrométricos e registrou-se o estado vital e reprodutivo, assim como evidências de perturbação e rebrotamento. Cerca de 75% das castanheiras foram encontradas em estado morto. A estrutura populacional das árvores vivas é envelhecida (DAP médio, 159 ± 0,55 cm, com baixa presença de jovens improdutivos (4,6%. Pouco mais da metade das castanheiras adultas sobreviventes (DAP > 40 cm apresentou evidências de frutificação. As árvores com frutos apresentaram uma área de copa significativamente maior que as improdutivas. São necessárias medidas urgentes de conservação e reflorestamento da população de castanheiras na região do estudo, em conformidade da legislação ambiental vigente.

  6. Molecular Cloning and Expression Analysis of a Catalase Gene (NnCAT) from Nelumbo nucifera.

    Science.gov (United States)

    Dong, Chen; Zheng, Xingfei; Diao, Ying; Wang, Youwei; Zhou, Mingquan; Hu, Zhongli

    2015-11-01

    Rapid amplification cDNA end (RACE) assay was established to achieve the complete cDNA sequence of a catalase gene (NnCAT) from Nelumbo nucifera. The obtained full-length cDNA was 1666 bp in size and contained a 1476-bp open reading frame. The 3D structural model of NnCAT was constructed by homology modeling. The putative NnCAT possessed all the main characteristic amino acid residues and motifs of catalase (CAT) protein family, and the phylogenetic analysis revealed that NnCAT grouped together with high plants. Moreover, recombinant NnCAT showed the CAT activity (758 U/mg) at room temperature, holding high activity during temperature range of 20-50 °C, then the optimal pH of recombinant protein was assessed from pH 4 to pH 11. Additionally, real-time PCR assay demonstrated that NnCAT mRNA was expressed in various tissues of N. nucifera, with the highest expression in young leaf and lowest level in the root, and mRNA level of NnCAT was significantly augmented in response to short-time mechanical wounding. Different expression pattern of NnCAT gene suggested that NnCAT probably played a defensive role in the initial stages of oxidative stress, regulating the level of reactive oxygen species (ROS) by extracellular stimuli such as short-time mechanical wounding.

  7. A new PANI biosensor based on catalase for cyanide determination.

    Science.gov (United States)

    Özcan, Hakkı Mevlüt; Aydin, Tuba

    2016-01-01

    Cyanide is one of the most widespread of compounds measured in environmental analysis due to their toxic effects on environment and health. We report a highly sensitive, reliable, selective amperometric sensor for determination of cyanide, using a polyaniline conductive polymer. The enzyme catalase was immobilized by electropolymerization. The steps during the immobilization were controlled by electrochemical impedance spectroscopy. Optimum pH, temperature, aniline concentration, enzyme concentration, and the number of scans obtained during electropolymerization, were investigated. In addition, the cyanide present in artificial waste water samples was determined. In the characterization studies of the biosensor, some parameters such as reproducibility and storage stability, were analyzed.

  8. Sequential alterations in the micro-localization of catalase in mouse liver after treatment with hypolipidemic drugs.

    Science.gov (United States)

    Klucis, E; Crane, D; Masters, C

    1984-11-01

    A comparative study has been carried out on the micro-localization of catalase in mouse tissues subsequent to treatment with a representative range of hypolipidemic drugs. A commonality of effect was shown by clofibrate (ethyl-alpha-p-chlorophenoxyisobutyrate), Wy-14,643 (4-chloro-6-[2,3 xylidino)-2-pyrimidinylthio] acetic acid), RMI-15,414 (5-tetradecyloxy-2-furancarboxylic acid) and aspirin (acetyl salicylic acid), in that treatments with each of these drugs was associated with the release of peroxisomal catalase into the cytoplasmic compartment of liver and kidney. It was also noticeable that this increased cytosolic activity was characterized by the presence of an 'aged' form of the enzyme with different mobility and activity characteristics to that of the peroxisomal enzyme. Possible molecular bases for these effects and their relationship to peroxisomal biogenesis are discussed.

  9. Investigation of the simultaneous production of superoxide dismutase and catalase enzymes from Rhodotorula glutinis under different culture conditions.

    Science.gov (United States)

    Unlü, Ayşe Ezgi; Takaç, Serpil

    2012-10-01

    The simultaneous production production of superoxide (SOD) and catalase (CAT) from Rhodotorula glutinis was studied. The effects of temperature, initial medium pH, and carbon source on the enzyme activities were investigated. Temperature and carbon sources were found to have significant effects on the enzyme activities. 10°C provided the highest specific CAT and SOD activities as 22.6 U/mg protein and 170 U/mg protein, respectively. Glycerol was found to be the best carbon source for enzyme activities, providing 113 U/mg protein for CAT and 125 U/mg protein for SOD, which were also the highest activities obtained in the present study.

  10. Covalent immobilization of catalase onto spacer-arm attached modified florisil: characterization and application to batch and plug-flow type reactor systems.

    Science.gov (United States)

    Alptekin, Ozlem; Tükel, S Seyhan; Yildirim, Deniz; Alagöz, Dilek

    2011-12-10

    Catalase was covalently immobilized onto florisil via glutaraldehyde (GA) and glutaraldehyde+6-amino hexanoic acid (6-AHA) (as a spacer arm). Immobilizations of catalase onto modified supports were optimized to improve the efficiency of the overall immobilization procedures. The V(max) values of catalase immobilized via glutaraldehyde (CIG) and catalase immobilized via glutaraldehyde+6-amino hexanoic acid (CIG-6-AHA) were about 0.6 and 3.4% of free catalase, respectively. The usage of 6-AHA as a spacer arm caused about 40 folds increase in catalytic efficiency of CIG-6-AHA (8.3 × 10⁵ M⁻¹ s⁻¹) as compared to that of CIG (2.1 × 10⁴ M⁻¹ s⁻¹). CIG and CIG-6-AHA retained 67 and 35% of their initial activities at 5 °C and 71 and 18% of their initial activities, respectively at room temperature at the end of 6 days. Operational stabilities of CIG and CIG-6-AHA were investigated in batch and plug-flow type reactors. The highest total amount of decomposed hydrogen peroxide (TAD-H₂O₂) was determined as 219.5 μmol for CIG-6-AHA in plug-flow type reactor. Copyright © 2011 Elsevier Inc. All rights reserved.

  11. Partial characterization and expression of leaf catalase in the CAM-inducible halophyte Mesembryanthemum crystallinum L.

    Science.gov (United States)

    Niewiadomska, Ewa; Miszalski, Zbigniew

    2008-04-01

    Catalase (CAT; EC 1.11.1.6) isolated from leaves of the halophytic plant Mesembryanthemum crystallinum is characterized by a high apparent molecular mass of about 320kDa, and high resistance to denaturing agents (10% ME). SDS-treatment breaks active oligomeric CAT into the less active and putatively dimeric form of 160kDa apparent molecular mass. Three subunits are resolved after denaturing PAGE: 79, 74 and 62kDa. Higher molecular masses of subunits coincide with increased activity of CAT. M. crystallinum leaf CAT reveals a diel variation in the resistance to denaturing factors and the stability of CAT is increased in a light-dependent manner both in C(3)- and in CAM-induced plants. Unchanged level of leaf CAT transcripts is documented in the diurnal cycle of C(3) plants and after salinity-induced crassulacean acid metabolism (CAM).

  12. Catalase degradation in sunflower cotyledons during peroxisome transition from glyoxysomal to leaf peroxisomal function. [Helianthus annuus

    Energy Technology Data Exchange (ETDEWEB)

    Eising, R.; Gerhardt, B.

    1987-06-01

    First order rate constant for the degradation (degradation constants) of catalase in the cotyledons of sunflower (Helianthus annuus L.) were determined by measuring the loss of catalase containing /sup 14/C-labeled heme. During greening of the cotyledons, a period when peroxisomes change from glyoxysomal to leaf peroxisomal function, the degradation of glyoxysomal catalase is significantly slower than during all other stages of cotyledon development in light or darkness. The degradation constant during the transition stage of peroxisome function amounts to 0.205 day/sup -1/ in contrast to the constants ranging from 0.304 day/sup -1/ to 0.515 day/sup -1/ during the other developmental stages. Density labeling experiments comprising labeling of catalase with /sup 2/H/sub 2/O and its isopycnic centrifugation on CsCl gradients demonstrated that the determinations of the degradation constants were not substantially affected by reutilization of /sup 14/C-labeled compounds for catalase synthesis. The degradation constants for both glyoxysomal catalase and catalase synthesized during the transition of peroxisome function do not differ. This was shown by labeling the catalases with different isotopes and measuring the isotope ratio during the development of the cotyledons. The results are inconsistent with the concept that an accelerated and selective degradation of glyoxysomes underlies the change in peroxisome function. The data suggest that catalase degradation is at least partially due to an individual turnover of catalase and does not only result from a turnover of the whole peroxisomes.

  13. Cyanobacterial Mn-catalase 'KatB': Molecular link between salinity and oxidative stress resistance.

    Science.gov (United States)

    Chakravarty, Dhiman; Banerjee, Manisha; Waghmare, Namrata; Ballal, Anand

    2016-01-01

    Catalases are ubiquitous enzymes that detoxify H 2 O 2 in virtually all organisms exposed to oxygen. The filamentous, nitrogen-fixing cyanobacterium, Anabaena PCC 7120, shows the presence of 2 genes ( katA and katB ) that encode Mn-catalases. We have recently shown that pre-treatment of Anabaena with NaCl causes substantial induction of the KatB protein, which consequently leads to increased oxidative stress resistance in that cyanobacterium. Interestingly, when compared to the wild-type, the katB mutant shows decreased growth and impaired photosynthetic activity in the presence of NaCl. Furthermore, the NaCl-treated katB mutant is extremely sensitive to H 2 O 2 . In this study, the ultrastructural changes occurring in the katB mutant and the wild-type Anabaena cells are analyzed to understand the cellular basis of the above-mentioned protective phenomena. Other data show that a wide variety of osmolytes induce katB expression in Anabaena , indicating that katB is a genuine osmo-inducible gene. These results have important biotechnological implications for the development of novel cyanobacterial biofertilzers and transgenic plants with improved resistance to salinity.

  14. Isonicotinic acid hydrazide conversion to Isonicotinyl-NAD by catalase-peroxidases.

    Science.gov (United States)

    Wiseman, Ben; Carpena, Xavi; Feliz, Miguel; Donald, Lynda J; Pons, Miquel; Fita, Ignacio; Loewen, Peter C

    2010-08-20

    Activation of the pro-drug isoniazid (INH) as an anti-tubercular drug in Mycobacterium tuberculosis involves its conversion to isonicotinyl-NAD, a reaction that requires the catalase-peroxidase KatG. This report shows that the reaction proceeds in the absence of KatG at a slow rate in a mixture of INH, NAD(+), Mn(2+), and O(2), and that the inclusion of KatG increases the rate by >7 times. Superoxide, generated by either Mn(2+)- or KatG-catalyzed reduction of O(2), is an essential intermediate in the reaction. Elimination of the peroxidatic process by mutation slows the rate of reaction by 60% revealing that the peroxidatic process enhances, but is not essential for isonicotinyl-NAD formation. The isonicotinyl-NAD(*+) radical is identified as a reaction intermediate, and its reduction by superoxide is proposed. Binding sites for INH and its co-substrate, NAD(+), are identified for the first time in crystal complexes of Burkholderia pseudomallei catalase-peroxidase with INH and NAD(+) grown by co-crystallization. The best defined INH binding sites were identified, one in each subunit, on the opposite side of the protein from the entrance to the heme cavity in a funnel-shaped channel. The NAD(+) binding site is approximately 20 A from the entrance to the heme cavity and involves interactions primarily with the AMP portion of the molecule in agreement with the NMR saturation transfer difference results.

  15. Isonicotinic Acid Hydrazide Conversion to Isonicotinyl-NAD by Catalase-peroxidases*

    Science.gov (United States)

    Wiseman, Ben; Carpena, Xavi; Feliz, Miguel; Donald, Lynda J.; Pons, Miquel; Fita, Ignacio; Loewen, Peter C.

    2010-01-01

    Activation of the pro-drug isoniazid (INH) as an anti-tubercular drug in Mycobacterium tuberculosis involves its conversion to isonicotinyl-NAD, a reaction that requires the catalase-peroxidase KatG. This report shows that the reaction proceeds in the absence of KatG at a slow rate in a mixture of INH, NAD+, Mn2+, and O2, and that the inclusion of KatG increases the rate by >7 times. Superoxide, generated by either Mn2+- or KatG-catalyzed reduction of O2, is an essential intermediate in the reaction. Elimination of the peroxidatic process by mutation slows the rate of reaction by 60% revealing that the peroxidatic process enhances, but is not essential for isonicotinyl-NAD formation. The isonicotinyl-NAD•+ radical is identified as a reaction intermediate, and its reduction by superoxide is proposed. Binding sites for INH and its co-substrate, NAD+, are identified for the first time in crystal complexes of Burkholderia pseudomallei catalase-peroxidase with INH and NAD+ grown by co-crystallization. The best defined INH binding sites were identified, one in each subunit, on the opposite side of the protein from the entrance to the heme cavity in a funnel-shaped channel. The NAD+ binding site is ∼20 Å from the entrance to the heme cavity and involves interactions primarily with the AMP portion of the molecule in agreement with the NMR saturation transfer difference results. PMID:20554537

  16. The Thr-His Connection on the Distal Heme of Catalase-Related Hemoproteins: A Hallmark of Reaction with Fatty Acid Hydroperoxides.

    Science.gov (United States)

    Mashhadi, Zahra; Newcomer, Marcia E; Brash, Alan R

    2016-11-03

    This review focuses on a group of heme peroxidases that retain the catalase fold in structure, yet show little or no reaction with hydrogen peroxide. Instead of having a role in oxidative defense, these enzymes are involved in secondary metabolite biosynthesis. The prototypical enzyme is catalase-related allene oxide synthase, an enzyme that converts a specific fatty acid hydroperoxide to the corresponding allene oxide (epoxide). Other catalase-related enzymes form allylic epoxides, aldehydes, or a bicyclobutane fatty acid. In all catalases (including these relatives), a His residue on the distal face of the heme is absolutely required for activity. Its immediate neighbor in sequence as well as in 3 D space is conserved as Val in true catalases and Thr in the fatty acid hydroperoxide-metabolizing enzymes. Thr-His on the distal face of the heme is critical in switching the substrate specificity from H2 O2 to fatty acid hydroperoxide. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Cj1386 Is an Ankyrin-Containing Protein Involved in Heme Trafficking to Catalase in Campylobacter jejuni

    Science.gov (United States)

    Flint, Annika; Sun, Yi-Qian

    2012-01-01

    Campylobacter jejuni, a microaerophilic bacterium, is the most frequent cause of human bacterial gastroenteritis. C. jejuni is exposed to harmful reactive oxygen species (ROS) produced during its own normal metabolic processes and during infection from the host immune system and from host intestinal microbiota. These ROS will damage DNA and proteins and cause peroxidation of lipids. Consequently, identifying ROS defense mechanisms is important for understanding how Campylobacter survives this environmental stress during infection. Construction of a ΔCj1386 isogenic deletion mutant and phenotypic assays led to its discovery as a novel oxidative stress defense gene. The ΔCj1386 mutant has an increased sensitivity toward hydrogen peroxide. The Cj1386 gene is located directly downstream from katA (catalase) in the C. jejuni genome. A ΔkatAΔ Cj1386 double deletion mutant was constructed and exhibited a sensitivity to hydrogen peroxide similar to that seen in the ΔCj1386 and ΔkatA single deletion mutants. This observation suggests that Cj1386 may be involved in the same detoxification pathway as catalase. Despite identical KatA abundances, catalase activity assays showed that the ΔCj1386 mutant had a reduced catalase activity relative to that of wild-type C. jejuni. Heme quantification of KatA protein from the ΔCj1386 mutant revealed a significant decrease in heme concentration. This indicates an important role for Cj1386 in heme trafficking to KatA within C. jejuni. Interestingly, the ΔCj1386 mutant had a reduced ability to colonize the ceca of chicks and was outcompeted by the wild-type strain for colonization of the gastrointestinal tract of neonate piglets. These results indicate an important role for Cj1386 in Campylobacter colonization and pathogenesis. PMID:22081390

  18. Temporal variation for the expression of catalase in Drosophila melanogaster: correlations between rates of enzyme synthesis and levels of translatable catalase-messenger RNA.

    Science.gov (United States)

    Bewley, G C; Mackay, W J; Cook, J L

    1986-08-01

    Two variants that alter the temporal expression of catalase have been isolated from a set of third chromosome substitution lines. Each variant has been mapped to a cytogenetic interval flanked by the visible markers st (3-44.0) and cu (3-50.0) at a map position of 47.0, which is within or near the interval 75D-76A previously identified as containing the catalase structural gene on the bases of dosage responses to segmental aneuploidy. Each variant operates by modulating the rate of enzyme synthesis and the level of translatable catalase-mRNA.

  19. Efeitos de nitrogênio, fósforo e potássio no crescimento de Rhapis excelsa (Thunberg Henry ex. Rehder (Palmeira-Ráfia Effects of nitrogen, phosphorus and potassium on early growth of seedlings of Rhapis Excelsa (Thunberg Henry ex. Rehder (Lady Palm

    Directory of Open Access Journals (Sweden)

    Petterson Baptista da Luz

    2006-06-01

    Full Text Available Rhapis excelsa é uma das palmeiras ornamentais mais cultivadas no mundo, indicadas principalmente para vasos e áreas de sombra. A maioria das palmeiras apresenta crescimento lento. O objetivo deste estudo é acelerar o processo de produção de mudas. Analisaram-se os efeitos da adubação realizada com nitrogênio, fósforo e potássio, sob o crescimento da espécie, ao longo de 8 meses. As mudas com altura de 3,80 cm foram plantadas em substrato constituído de partes iguais de terra e vermiculita. Realizaram-se aplicações semanais de NPK, diretamente no solo, na concentração de 10 mg.L-1 de substrato, utilizando-se como fonte: MAP (P, sulfato de amônio (N e cloreto de potássio (K. Os tratamentos foram constituídos de todas as combinações possíveis destes nutrientes, mais uma testemunha. O experimento foi mantido em casa-de-vegetação com nebulização. Avaliaram-se os resultados com base na produção de matéria seca da parte aérea e das raízes, área foliar, diâmetro do caule, número de folhas e altura do estipe. O nutriente que proporcionou um maior desenvolvimento e crescimento da palmeira Rhapis excelsa foi o nitrogênio, influenciando de forma positiva na maioria dos parâmetros analisados. Verificou-se melhor desenvolvimento das mudas com a aplicação de N, independente da combinação com P e ou K.Rhapis excelsa is one of the most cultivated ornamental palms of the world, indicated for cultivation in pots and under shadow. Most of the palm trees present slow growth. The objective of this study was to investigate the influence of fertilization on acceleration of palm seedlings production. The effects of nitrogen, phosphorus and potassium fertilizers on the growth of seedlings of this specie, during 8 months, were investigated in this work. Seedlings with 3.80 cm of height were cultivated in a substrate constituted of equal parts of soil and vermiculite. Applications of NPK were made weekly, at the concentration of 10

  20. Effect of vitamin C and lipoic acid on streptozotocin-induced diabetes gene expression: mRNA and protein expressions of Cu-Zn SOD and catalase.

    Science.gov (United States)

    Sadi, Gökhan; Yilmaz, Okkes; Güray, Tülin

    2008-02-01

    The involvement of oxidative stress in the pathogenesis of diabetes mellitus has been confirmed by numerous studies. In this study, the expression of two antioxidant enzymes, superoxide dismutase (SOD), and catalase which are involved in the detoxification of reactive oxygen species was studied in the streptozotocin-induced diabetic rat liver tissues. The enzyme assays showed a significant decrease in both enzymes activities compared to control animals. The RT-PCR and Western-blot analysis results demonstrated that this decrease in activity is regulated at the level of gene expression, as both catalase and Cu-Zn SOD mRNA and protein expressions were also suppressed. Supplementing the animals with vitamin C, a powerful antioxidant increased both SOD and catalase activities with no change in both mRNA and protein expressions suggesting a role of post-translational modification. However, even though mRNA expressions of both catalase and Cu-Zn SOD were not changed, the protein levels increased in parallel to activities in the case of another antioxidant, alpha-lipoic acid. An increase in the rate of translation, without changing the rate of transcription indicates a translational effect of lipoic acid in changing the activities of antioxidant enzymes to prevent the oxidative damage in diabetes.

  1. In vitro and in vivo inhibitory effects of some fungicides on catalase produced and purified from white-rot fungus Phanerochaete chrysosporium.

    Science.gov (United States)

    Kavakçıoğlu, Berna; Tarhan, Leman

    2014-10-01

    In this study, in vitro and in vivo effects of some commonly used fungicides, antibiotics, and various chemicals on isolated and purified catalase from Phanerochaete chrysosporium were investigated. The catalase was purified 129.10-fold by using 60% ammonium sulfate and 60% ethanol precipitations, DEAE-cellulose anion exchange and Sephacryl-S-200 gel filtration chromatographies from P. chrysosporium growth in carbon- and nitrogen-limited medium for 12 days. The molecular weight of native purified catalase from P. chrysosporium was found to be 290 ± 10 kDa, and sodium dodecyl sulfate (SDS)-PAGE results indicated that enzyme consisted of four apparently identical subunits, with a molecular weight of 72.5 ± 2.5 kDa. Kinetic characterization studies showed that optimum pH and temperature, Km and Vmax values of the purified catalase which were stable in basic region and at comparatively high temperatures were 7.5, 30°C, 289.86 mM, and 250,000 U/mg, respectively. The activity of purified catalase from P. chrysosporium was significantly inhibited by dithiothreitol (DTT), 2-mercaptoethanol, iodoacetamide, EDTA, and sodium dodecyl sulfate (SDS). It was found that while antibiotics had no inhibitory effects, 45 ppm benomyl, 144 ppm captan, and 47.5 ppm chlorothalonil caused 14.52, 10.82, and 38.86% inhibition of purified catalase, respectively. The inhibition types of these three fungicides were found to be non-competitive inhibition with the Ki values of 1.158, 0.638, and 0.145 mM and IC50 values of 0.573, 0.158, 0.010 mM, respectively. The results of in vivo experiments also showed that benomyl, captan and chlorothalonil caused 15.25, 1.96, and 36.70% activity decreases after 24-h treatments compared to that of the control.

  2. siRNA-based Analysis of the Abrogation of the Protective Function of Membrane-associated Catalase of Tumor Cells.

    Science.gov (United States)

    Bauer, Georg

    2017-02-01

    Tumor cells, in contrast to non-malignant cells, show sustained expression of membrane-associated NADPH oxidase-1 and therefore generate extracellular superoxide anions and their dismutation product H2O2 In order to prevent intercellular reactive oxygen species/reactive nitrogen species (ROS/RNS)-dependent apoptosis-inducing signaling, tumor cells need to express membrane-associated catalase that interferes with HOCl and nitric oxide/peroxynitrite signaling. Catalase is attached to tumor cells through the activity of transglutaminase-2 and is prevented from superoxide anion-dependent inhibition through coexpression of membrane-associated superoxide dismutase. Therefore, specific inhibition of membrane-associated catalase should reactivate intercellular ROS/RNS-dependent apoptosis-inducing signaling. These processes are analyzed here through small interfering RNA-mediated knockdown of essential signaling compounds. This allows to establish a rather comprehensive picture of intercellular ROS/RNS signaling that may be instrumental for future therapeutic approaches. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  3. Enhanced hippocampus-dependent memory and reduced anxiety in mice over-expressing human catalase in mitochondria.

    Science.gov (United States)

    Olsen, Reid H J; Johnson, Lance A; Zuloaga, Damian G; Limoli, Charles L; Raber, Jacob

    2013-04-01

    Oxidative stress (OS) and reactive oxygen species (ROS) play a modulatory role in synaptic plasticity and signaling pathways. Mitochondria (MT), a major source of ROS because of their involvement in energy metabolism, are important for brain function. MT-generated ROS are proposed to be responsible for a significant proportion of OS and are associated with developmental abnormalities and aspects of cellular aging. The role of ROS and MT function in cognition of healthy individuals is relatively understudied. In this study, we characterized behavioral and cognitive performance of 5- to 6-month-old mice over-expressing mitochondrial catalase (MCAT). MCAT mice showed enhancements in hippocampus-dependent spatial learning and memory in the water maze and contextual fear conditioning, and reduced measures of anxiety in the elevated zero maze. Catalase activity was elevated in MCAT mice in all brain regions examined. Measures of oxidative stress (glutathione, protein carbonyl content, lipid peroxidation, and 8-hydroxyguanine) did not significantly differ between the groups. The lack of differences in these markers of oxidative stress suggests that the differences observed in this study may be due to altered redox signaling. Catalase over-expression might be sufficient to enhance cognition and reduce measures of anxiety even in the absence of alteration in levels of OS. © 2013 International Society for Neurochemistry.

  4. Catalase Expression Is Modulated by Vancomycin and Ciprofloxacin and Influences the Formation of Free Radicals in Staphylococcus aureus Cultures.

    Science.gov (United States)

    Wang, Ying; Hougaard, Anni B; Paulander, Wilhelm; Skibsted, Leif H; Ingmer, Hanne; Andersen, Mogens L

    2015-09-01

    Detection of free radicals in biological systems is challenging due to their short half-lives. We have applied electron spin resonance (ESR) spectroscopy combined with spin traps using the probes PBN (N-tert-butyl-α-phenylnitrone) and DMPO (5,5-dimethyl-1-pyrroline N-oxide) to assess free radical formation in the human pathogen Staphylococcus aureus treated with a bactericidal antibiotic, vancomycin or ciprofloxacin. While we were unable to detect ESR signals in bacterial cells, hydroxyl radicals were observed in the supernatant of bacterial cell cultures. Surprisingly, the strongest signal was detected in broth medium without bacterial cells present and it was mitigated by iron chelation or by addition of catalase, which catalyzes the decomposition of hydrogen peroxide to water and oxygen. This suggests that the signal originates from hydroxyl radicals formed by the Fenton reaction, in which iron is oxidized by hydrogen peroxide. Previously, hydroxyl radicals have been proposed to be generated within bacterial cells in response to bactericidal antibiotics. We found that when S. aureus was exposed to vancomycin or ciprofloxacin, hydroxyl radical formation in the broth was indeed increased compared to the level seen with untreated bacterial cells. However, S. aureus cells express catalase, and the antibiotic-mediated increase in hydroxyl radical formation was correlated with reduced katA expression and catalase activity in the presence of either antibiotic. Therefore, our results show that in S. aureus, bactericidal antibiotics modulate catalase expression, which in turn influences the formation of free radicals in the surrounding broth medium. If similar regulation is found in other bacterial species, it might explain why bactericidal antibiotics are perceived as inducing formation of free radicals. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  5. Multiple abiotic stress tolerance of the transformants yeast cells and the transgenic Arabidopsis plants expressing a novel durum wheat catalase.

    Science.gov (United States)

    Feki, Kaouthar; Kamoun, Yosra; Ben Mahmoud, Rihem; Farhat-Khemakhem, Ameny; Gargouri, Ali; Brini, Faiçal

    2015-12-01

    Catalases are reactive oxygen species scavenging enzymes involved in response to abiotic and biotic stresses. In this study, we described the isolation and functional characterization of a novel catalase from durum wheat, designed TdCAT1. Molecular Phylogeny analyses showed that wheat TdCAT1 exhibited high amino acids sequence identity to other plant catalases. Sequence homology analysis showed that TdCAT1 protein contained the putative calmodulin binding domain and a putative conserved internal peroxisomal targeting signal PTS1 motif around its C-terminus. Predicted three-dimensional structural model revealed the presence of four putative distinct structural regions which are the N-terminal arm, the β-barrel, the wrapping and the α-helical domains. TdCAT1 protein had the heme pocket that was composed by five essential residues. TdCAT1 gene expression analysis showed that this gene was induced by various abiotic stresses in durum wheat. The expression of TdCAT1 in yeast cells and Arabidopsis plants conferred tolerance to several abiotic stresses. Compared with the non-transformed plants, the transgenic lines maintained their growth and accumulated more proline under stress treatments. Furthermore, the amount of H2O2 was lower in transgenic lines, which was due to the high CAT and POD activities. Taken together, these data provide the evidence for the involvement of durum wheat catalase TdCAT1 in tolerance to multiple abiotic stresses in crop plants. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  6. Investigation on the toxic interaction of superparamagnetic iron oxide nanoparticles with catalase

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Zehua [Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, China–America CRC for Environment and Health, Shandong Province, Shandong University, 27# Shanda South Road, Jinan 250100 (China); Liu, Hongwei [Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, China–America CRC for Environment and Health, Shandong Province, Shandong University, 27# Shanda South Road, Jinan 250100 (China); Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China); Hu, Xinxin; Song, Wei [Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, China–America CRC for Environment and Health, Shandong Province, Shandong University, 27# Shanda South Road, Jinan 250100 (China); Liu, Rutao, E-mail: rutaoliu@sdu.edu.cn [Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, China–America CRC for Environment and Health, Shandong Province, Shandong University, 27# Shanda South Road, Jinan 250100 (China)

    2015-03-15

    Superparamagnetic iron oxide nanoparticles (SPIONs) have been investigated for various applications in targeted drug delivery and magnetic resonance imaging. Given their clinical relevance, there is a need to understand these particles' potential cytotoxic effects and possible mechanisms of cytotoxicity. Using a variety of spectroscopic techniques, we investigated the interaction of SPIONs with catalase (CAT) in an aqueous environment. Catalase is an important enzyme that protects cells and tissues from oxidative damage by reactive oxygen species (ROS). Therefore, in this work, CAT served as a model protein for examining the physiological effects of SPIONs due to is function in eliminating H{sub 2}O{sub 2}. Synchronous fluorescence spectroscopy results showed that SPIONs have little effect on tryptophan residues in CAT. Data from circular dichroism (CD) and UV–vis spectroscopies showed that CAT α-helical content decreased from 32.4% to 29.1% in the presence of SPIONs. Moreover, a ca. 10% decrease in CAT activity was observed in the presence of SPIONs at a 20:1 particle:protein ratio. These results show that SPIONs can interact with proteins to alter both their structure and function. Further studies with CAT or other toxicologically relevant enzymes may be used for elucidating the mechanisms of SPION cytotoxicity. - Highlights: • This work established the binding mode of SPIONs with CAT on molecular level. • The interaction mechanism was explored by multiple spectroscopic techniques. • SPIONs can loosen the skeleton of protein and increase the exposure of amide moieties in the hydrophobic pocket. • SPIONs can inhibit CAT activity and trigger conformational changes in CAT.

  7. Investigation of Catalase, Proxidase and Total Protein Level in Some Cold Treated Grapevine Cultivars Cold Stress Response

    Directory of Open Access Journals (Sweden)

    M. Karimi Alavijeh

    2016-02-01

    Full Text Available Chilling is an important environmental stress that influences the yield and quality of many agricultural crops. Different plants use different systems to endure this stress and minimize its effects. One of these systems is enzymatic reaction. To find out more about responses of different grapevine species and cultivars to the low temperature conditions, their enzymatic changes were evaluated in a factorial experiment based on randomized complete design with 3 replication during different periods after chilling stress. Leaf samples of plants under cold stress had been taken and maintained in -80 °C until enzyme extraction. Low temperature around 4 °C is sufficient to induce genes that produce chilling acclimatization proteins. In the present study, leaf samples were collected from the plants that were kept at 4 °C during different time intervals, and then total proteins as well as two main antioxidant enzymes (catalase and guaiacolperoxidase activities were measured. Results showed that as temperature decreased, enzymatic activities were increased in six Iranian grapevine cultivars (‘Atabaki’, ‘Khalili-Danedar’, ‘Shahroodi’, ‘Rajabi-Siah’, ‘Askari’ and ‘Bidane-Sefid’ as well as ‘Riparia’, an American species. The highest enzymatic activities of catalase and ceroxidase were recorded in ‘Khalili-Danedar’ and ‘Riparia’. However,the lowest activities were recorded in ‘Rajabi-Siah’, ‘Bidane-Sefid’ and ‘Shahroodi’. For all studied cultivars, peroxidase showed its highest activity at 12 h after chilling stress, then remained constant, while, the highest activity of catalase were recorded at 8 h. In addition, cold stress increased the total protein content for all studied cultivars, in which ‘Khalili-Danedar’ had the highest protein content amongstudied cultivars. Also, the highest proteins content were recorded at 12 h after exposing plants to cold.

  8. Production and characterisation of monoclonal antibodies against native and disassembled human catalase

    NARCIS (Netherlands)

    Wiemer, E. A.; Ofman, R.; Middelkoop, E.; de Boer, M.; Wanders, R. J.; Tager, J. M.

    1992-01-01

    Catalase isolated from human erythrocytes was used to immunise mice, in order to generate hybridomas producing specific monoclonal antibodies to the enzyme. Hybridomas secreting anti-(catalase) antibodies were identified by a modified enzyme-linked immunosorbent assay (ELISA) using either

  9. Location of catalase in crystalline peroxisomes of methanol-grown Hansenula polymorpha

    NARCIS (Netherlands)

    Keizer, Ineke; Roggenkamp, Rainer; Harder, Willem; Veenhuis, Marten

    1992-01-01

    We have studied the intraperoxisomal location of catalase in peroxisomes of methanol-grown Hansenula polymorpha by (immuno)cytochemical means. In completely crystalline peroxisomes, in which the crystalline matrix is composed of octameric alcohol oxidase (AO) molecules, most of the catalase protein

  10. Enhanced alkaline catalase production by Serratia marcescens FZSF01: Enzyme purification, characterization, and recombinant expression

    Directory of Open Access Journals (Sweden)

    Xianbo Jia

    2017-11-01

    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.

  11. Purification, biochemical characterization, and implications of an alkali-tolerant catalase from the spacecraft-associated and oxidation-resistant Acinetobacter gyllenbergii 2P01AA.

    Science.gov (United States)

    Muster, N; Derecho, I; Dallal, F; Alvarez, R; McCoy, K B; Mogul, R

    2015-04-01

    Herein, we report on the purification, characterization, and sequencing of catalase from Acinetobacter gyllenbergii 2P01AA, an extremely oxidation-resistant bacterium that was isolated from the Mars Phoenix spacecraft assembly facility. The Acinetobacter are dominant members of the microbial communities that inhabit spacecraft assembly facilities and consequently may serve as forward contaminants that could impact the integrity of future life-detection missions. Catalase was purified by using a 3-step chromatographic procedure, where mass spectrometry provided respective subunit and intact masses of 57.8 and 234.6 kDa, which were consistent with a small-subunit tetrameric catalase. Kinetics revealed an extreme pH stability with no loss in activity between pH 5 and 11.5 and provided respective kcat/Km and kcat values of ∼10(7) s(-1) M(-1) and 10(6) s(-1), which are among the highest reported for bacterial catalases. The amino acid sequence was deduced by in-depth peptide mapping, and structural homology suggested that the catalases from differing strains of A. gyllenbergii differ only at residues near the subunit interfaces, which may impact catalytic stability. Together, the kinetic, alkali-tolerant, and halotolerant properties of the catalase from A. gyllenbergii 2P01AA are significant, as they are consistent with molecular adaptations toward the alkaline, low-humidity, and potentially oxidizing conditions of spacecraft assembly facilities. Therefore, these results support the hypothesis that the selective pressures of the assembly facilities impact the microbial communities at the molecular level, which may have broad implications for future life-detection missions.

  12. The peroxisomal import receptor PEX5 functions as a stress sensor, retaining catalase in the cytosol in times of oxidative stress.

    Science.gov (United States)

    Walton, Paul A; Brees, Chantal; Lismont, Celien; Apanasets, Oksana; Fransen, Marc

    2017-10-01

    Accumulating evidence indicates that peroxisome functioning, catalase localization, and cellular oxidative balance are intimately interconnected. Nevertheless, it remains largely unclear why modest increases in the cellular redox state especially interfere with the subcellular localization of catalase, the most abundant peroxisomal antioxidant enzyme. This study aimed at gaining more insight into this phenomenon. Therefore, we first established a simple and powerful approach to study peroxisomal protein import and protein-protein interactions in living cells in response to changes in redox state. By employing this approach, we confirm and extend previous observations that Cys-11 of human PEX5, the shuttling import receptor for peroxisomal matrix proteins containing a C-terminal peroxisomal targeting signal (PTS1), functions as a redox switch that modulates the protein's activity in response to intracellular oxidative stress. In addition, we show that oxidative stress affects the import of catalase, a non-canonical PTS1-containing protein, more than the import of a reporter protein containing a canonical PTS1. Furthermore, we demonstrate that changes in the local redox state do not affect PEX5-substrate binding and that human PEX5 does not oligomerize in cellulo, not even when the cells are exposed to oxidative stress. Finally, we present evidence that catalase retained in the cytosol can protect against H2O2-mediated redox changes in a manner that peroxisomally targeted catalase does not. Together, these findings lend credit to the idea that inefficient catalase import, when coupled with the role of PEX5 as a redox-regulated import receptor, constitutes a cellular defense mechanism to combat oxidative insults of extra-peroxisomal origin. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Singlet oxygen treatment of tumor cells triggers extracellular singlet oxygen generation, catalase inactivation and reactivation of intercellular apoptosis-inducing signaling.

    Science.gov (United States)

    Riethmüller, Michaela; Burger, Nils; Bauer, Georg

    2015-12-01

    Intracellular singlet oxygen generation in photofrin-loaded cells caused cell death without discrimination between nonmalignant and malignant cells. In contrast, extracellular singlet oxygen generation caused apoptosis induction selectively in tumor cells through singlet oxygen-mediated inactivation of tumor cell protective catalase and subsequent reactivation of intercellular ROS-mediated apoptosis signaling through the HOCl and the NO/peroxynitrite signaling pathway. Singlet oxygen generation by extracellular photofrin alone was, however, not sufficient for optimal direct inactivation of catalase, but needed to trigger the generation of cell-derived extracellular singlet oxygen through the interaction between H2O2 and peroxynitrite. Thereby, formation of peroxynitrous acid, generation of hydroxyl radicals and formation of perhydroxyl radicals (HO2(.)) through hydroxyl radical/H2O2 interaction seemed to be required as intermediate steps. This amplificatory mechanism led to the formation of singlet oxygen at a sufficiently high concentration for optimal inactivation of membrane-associated catalase. At low initial concentrations of singlet oxygen, an additional amplification step needed to be activated. It depended on singlet oxygen-dependent activation of the FAS receptor and caspase-8, followed by caspase-8-mediated enhancement of NOX activity. The biochemical mechanisms described here might be considered as promising principle for the development of novel approaches in tumor therapy that specifically direct membrane-associated catalase of tumor cells and thus utilize tumor cell-specific apoptosis-inducing ROS signaling. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  14. Singlet oxygen treatment of tumor cells triggers extracellular singlet oxygen generation, catalase inactivation and reactivation of intercellular apoptosis-inducing signaling☆

    Science.gov (United States)

    Riethmüller, Michaela; Burger, Nils; Bauer, Georg

    2015-01-01

    Intracellular singlet oxygen generation in photofrin-loaded cells caused cell death without discrimination between nonmalignant and malignant cells. In contrast, extracellular singlet oxygen generation caused apoptosis induction selectively in tumor cells through singlet oxygen-mediated inactivation of tumor cell protective catalase and subsequent reactivation of intercellular ROS-mediated apoptosis signaling through the HOCl and the NO/peroxynitrite signaling pathway. Singlet oxygen generation by extracellular photofrin alone was, however, not sufficient for optimal direct inactivation of catalase, but needed to trigger the generation of cell-derived extracellular singlet oxygen through the interaction between H2O2 and peroxynitrite. Thereby, formation of peroxynitrous acid, generation of hydroxyl radicals and formation of perhydroxyl radicals (HO2.) through hydroxyl radical/H2O2 interaction seemed to be required as intermediate steps. This amplificatory mechanism led to the formation of singlet oxygen at a sufficiently high concentration for optimal inactivation of membrane-associated catalase. At low initial concentrations of singlet oxygen, an additional amplification step needed to be activated. It depended on singlet oxygen-dependent activation of the FAS receptor and caspase-8, followed by caspase-8-mediated enhancement of NOX activity. The biochemical mechanisms described here might be considered as promising principle for the development of novel approaches in tumor therapy that specifically direct membrane-associated catalase of tumor cells and thus utilize tumor cell-specific apoptosis-inducing ROS signaling. PMID:26225731

  15. Purification of camel liver catalase by zinc chelate affinity chromatography and pH gradient elution: An enzyme with interesting properties.

    Science.gov (United States)

    Chafik, Abdelbasset; Essamadi, Abdelkhalid; Çelik, Safinur Yildirim; Mavi, Ahmet

    2017-12-01

    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, β-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. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Human Islet Amyloid Polypeptide Fibril Binding to Catalase: A Transmission Electron Microscopy and Microplate Study

    Directory of Open Access Journals (Sweden)

    Nathaniel G. N. Milton

    2010-01-01

    Full Text Available The diabetes-associated human islet amyloid polypeptide (IAPP is a 37-amino-acid peptide that forms fibrils in vitro and in vivo. Human IAPP fibrils are toxic in a similar manner to Alzheimer's amyloid-β (Aβ and prion protein (PrP fibrils. Previous studies have shown that catalase binds to Aβ fibrils and appears to recognize a region containing the Gly-Ala-Ile-Ile sequence that is similar to the Gly-Ala-Ile-Leu sequence found in human IAPP residues 24-27. This study presents a transmission electron microscopy (TEM—based analysis of fibril formation and the binding of human erythrocyte catalase to IAPP fibrils. The results show that human IAPP 1-37, 8-37, and 20-29 peptides form fibrils with diverse and polymorphic structures. All three forms of IAPP bound catalase, and complexes of IAPP 1-37 or 8-37 with catalase were identified by immunoassay. The binding of biotinylated IAPP to catalase was high affinity with a KD of 0.77nM, and could be inhibited by either human or rat IAPP 1-37 and 8-37 forms. Fibrils formed by the PrP 118-135 peptide with a Gly-Ala-Val-Val sequence also bound catalase. These results suggest that catalase recognizes a Gly-Ala-Ile-Leu—like sequence in amyloid fibril-forming peptides. For IAPP 1-37 and 8-37, the catalase binding was primarily directed towards fibrillar rather than ribbon-like structures, suggesting differences in the accessibility of the human IAPP 24-27 Gly-Ala-Ile-Leu region. This suggests that catalase may be able to discriminate between different structural forms of IAPP fibrils. The ability of catalase to bind IAPP, Aβ, and PrP fibrils demonstrates the presence of similar accessible structural motifs that may be targets for antiamyloid therapeutic development.

  17. Detection of Catalase as a major protein target of the lipid peroxidation product 4-HNE and the lack of its genetic association as a risk factor in SLE

    Directory of Open Access Journals (Sweden)

    Matsumoto Hiroyuki

    2008-07-01

    C → T, -262 bp polymorphism in the promoter region of catalase were non-significant (p > 0.05 in our data, which suggested that this SNP is not associated with SLE. Conclusion Our results indicate that catalase is one of the proteins modified due to oxidative stress. However, catalase may not be a susceptibility gene for SLE. Nonetheless, catalase is oxidatively modified among SLE patients. This suggests a possible role between oxidative modification of catalase and its affects on enzymatic activity in SLE. An oxidatively modified catalase could be one of the reasons for lower enzymatic activity among SLE subjects, which in turn could favor the accumulation of deleterious hydrogen peroxide. Furthermore, HNE-products are potential neoantigens and could be involved in the pathogenesis of SLE. Decrease in catalase activity could affect the oxidant-antioxidant balance. Chronic disturbance of this balance in patients with SLE may work favorably for the premature onset of atherogenesis with severe vascular effect.

  18. Peroxide reduction by a metal-dependent catalase in Nostoc punctiforme (cyanobacteria).

    Science.gov (United States)

    Hudek, L; Torriero, A A J; Michalczyk, A A; Neilan, B A; Ackland, M L; Bräu, Lambert

    2017-05-01

    This study investigated the role of a novel metal-dependent catalase (Npun_R4582) that reduces hydrogen peroxide in the cyanobacterium Nostoc punctiforme. Quantitative real-time PCR showed that npun_R4582 relative mRNA levels were upregulated by over 16-fold in cells treated with either 2 μM added Co, 0.5 μM added Cu, 500 μM Mn, 1 μM Ni, or 18 μM Zn. For cells treated with 60 μM H2O2, no significant alteration in Npun_R4582 relative mRNA levels was detected, while in cells treated with Co, Cu, Mn, Ni, or Zn and 60 μM peroxide, relative mRNA levels were generally above control or peroxide only treated cells. Disruption or overexpression of npun_R4582 altered sensitivity to cells exposed to 60 μM H2O2 and metals for treatments beyond the highest viable concentrations, or in a mixed metal solution for Npun_R4582- cells. Moreover, overexpression of npun_R4582 increased cellular peroxidase activity in comparison with wild-type and Npun_R4582- cells, and reduced peroxide levels by over 50%. The addition of cobalt, manganese, nickel, and zinc increased the capacity of Npun_R4582 to reduce the rate or total levels of peroxide produced by cells growing under photooxidative conditions. The work presented confirms the function of NpunR4582 as a catalase and provides insights as to how cells reduce potentially lethal peroxide levels produced by photosynthesis. The findings also show how trace elements play crucial roles as enzymatic cofactors and how the role of Npun_R4582 in hydrogen peroxide breakdown is dependent on the type of metal and the level available to cells.

  19. Interaction of chromium(III) or chromium(VI) with catalase and its effect on the structure and function of catalase: An in vitro study.

    Science.gov (United States)

    Chen, Linfeng; Zhang, Jing; Zhu, Yaxian; Zhang, Yong

    2018-04-01

    Heavy metal chromium (Cr) poses a severe health risk to humans via food chain contamination. In this study, the interactions of either trivalent chromium (Cr(III)) or hexavalent chromium (Cr(VI)) with catalase (CAT) were investigated via multi-spectroscopic studies and computational simulations. The fluorescence analysis showed that Cr(III) and Cr(VI) quenched the fluorescence of CAT through a dynamic and a static quenching mechanism, respectively. The binding constant of Cr(VI) with CAT was 3.44×10(4)lmol(-1) at 298K. Other detailed binding characterizations of the Cr(VI)-CAT complex were also obtained using spectra analysis and molecular docking. Synchronous fluorescence, UV-vis and circular dichroism (CD) spectral studies showed that either Cr(III) or Cr(VI) induced conformational changes of CAT, but the degree of influence was different. The response of CAT activity to Cr(III) or Cr(VI) was found to be variable depending on their valence states and concentrations. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. PRODUÇÃO DE FRUTOS DE URUCURIZEIROS, Attalea excelsa Mart. (ARECACEAE, EM FLORESTA DE VÁRZEA NO ESTUÁRIO DO RIO AMAZONAS

    Directory of Open Access Journals (Sweden)

    Adelson Rocha Dantas

    2014-12-01

    Full Text Available O objetivo deste trabalho foi avaliar a produção de frutos de Attalea excelsa, visando facilitar a definição dos estoques disponíveis para gerar estratégias de manejo e conservação da espécie. O estudo foi desenvolvido na floresta de várzea do Campo Experimental da Embrapa Amapá, em Mazagão-AP, como parte do projeto Florestam (ecologia e manejo para uso múltiplo de várzeas do estuário amazônico. Em 2011 foi realizado inventário de 100% de todos os indivíduos com CAP 30 cm em área de 56 ha. De 213 indivíduos inventariados, foram selecionados, aleatoriamente, 36 para monitoramento da produção de frutos. Foram determinados o comprimento, diâmetro e massa dos cachos e dos frutos. Também foi avaliado o rendimento das partes constituintes (bráctea, endocarpo, mesocarpo e pirênio dos frutos. Foram realizadas análises de agrupamentos, correlações e estatística descritiva das variáveis ligadas à produção. A produção média de cachos foi de 1,5, variando de 1 a 4 cachos/urucurizeiro. Um cacho produz, em média, 415 ± 222 frutos, variando de 96 a 1.102 frutos/cacho. Os frutos são alongados, pois possuem comprimento médio (72,5 mm maior do que o diâmetro (45,6. O mesocarpo apresentou um baixo percentual de rendimento (24,8%, com valores semelhantes ao endocarpo (24,2%. O pirênio é a maior parte constituinte (45,1% do fruto. Um urucurizeiro produz em média 629 ± 387 frutos, com elevada variação na produção. A análise de agrupamento em função dos atributos da quantidade e biometria dos frutos revelou de cinco a sete grupos de matrizes distintas, permitindo a seleção de matrizes com maior produção. Palavras-chave: biometria, produto não-madeireiro, seleção de matrizes, Amapá, projeto Florestam. DOI: http://dx.doi.org/10.18561/2179-5746/biotaamazonia.v4n4p108-114

  1. Structural characterization of the Ser324Thr variant of the catalase-peroxidase (KatG) from Burkholderia pseudomallei.

    Science.gov (United States)

    Deemagarn, Taweewat; Carpena, Xavier; Singh, Rahul; Wiseman, Ben; Fita, Ignacio; Loewen, Peter C

    2005-01-07

    The Ser315Thr variant of the catalase-peroxidase KatG from Mycobacterium tuberculosis imparts resistance to the pro-drug isonicotinic acid hydrazide (isoniazid) through a failure to convert it to the active drug, isonicotinoyl-NAD. The equivalent variant in KatG from Burkholderia pseudomallei, Ser324Thr, has been constructed, revealing catalase and peroxidase activities that are similar to those of the native enzyme. The other activities of the variant protein, including the NADH oxidase, the isoniazid hydrazinolysis and isonicotinoyl-NAD synthase activities are reduced by 60-70%. The crystal structure of the variant differs from that of the native enzyme in having the methyl group of Thr324 situated in the entrance channel to the heme cavity, in a modified water matrix in the entrance channel and heme cavity, in lacking the putative perhydroxy modification on the heme, in the multiple locations of a few side-chains, and in the presence of an apparent perhydroxy modification on the indole nitrogen atom of the active-site Trp111. The position of the methyl group of Thr324 creates a constriction or narrowing of the channel leading to the heme cavity, providing an explanation for the lower reactivity towards isoniazid and the slower rate of isonicotinoyl-NAD synthesis.

  2. Over-Expression of Catalase in Myeloid Cells Confers Acute Protection Following Myocardial Infarction

    Directory of Open Access Journals (Sweden)

    E. Bernadette Cabigas

    2014-05-01

    Full Text Available Cardiovascular disease is the leading cause of death in the United States and new treatment options are greatly needed. Oxidative stress is increased following myocardial infarction and levels of antioxidants decrease, causing imbalance that leads to dysfunction. Therapy involving catalase, the endogenous scavenger of hydrogen peroxide (H2O2, has been met with mixed results. When over-expressed in cardiomyocytes from birth, catalase improves function following injury. When expressed in the same cells in an inducible manner, catalase showed a time-dependent response with no acute benefit, but a chronic benefit due to altered remodeling. In myeloid cells, catalase over-expression reduced angiogenesis during hindlimb ischemia and prevented monocyte migration. In the present study, due to the large inflammatory response following infarction, we examined myeloid-specific catalase over-expression on post-infarct healing. We found a significant increase in catalase levels following infarction that led to a decrease in H2O2 levels, leading to improved acute function. This increase in function could be attributed to reduced infarct size and improved angiogenesis. Despite these initial improvements, there was no improvement in chronic function, likely due to increased fibrosis. These data combined with what has been previously shown underscore the need for temporal, cell-specific catalase delivery as a potential therapeutic option.

  3. Sunflower cotyledons cope with copper stress by inducing catalase subunits less sensitive to oxidation.

    Science.gov (United States)

    Pena, Liliana B; Azpilicueta, Claudia E; Gallego, Susana M

    2011-07-01

    Copper is an essential trace element for living organisms, in excess, can be toxic to the cell because of its capacity to generate reactive oxygen species (ROS). Catalase (CAT) catalyzes the dismutation of hydrogen peroxide into water and dioxygen and in plants it is located in peroxisomes and glyoxysomes. Different metals can induce changes in CAT activity, but the mechanism underlying its changes is unclear. After 4h of treatment with 5 and 10 μM CuCl(2) a decrease in the specific CAT activity was detected in sunflower cotyledons of post-germinative heterotrophic seedlings. At 8h of treatment, 5 μM Cu(2+) produced an induction of CAT activity while only a complete recovery to control values was observed for 10 μM Cu(2+) treated seedlings. These activity variations were not related to the level of CAT protein expression, but they did correlate with the oxidative state of the CAT protein. This indicates that the mechanism of CAT inactivation by Cu(2+) involves oxidation of the protein structure. The level of the mRNA of CATA3 and CATA4 increased with the presence of the metal after 4h of exposure. These CAT genes code for the synthesis of CAT subunits less sensitive to oxidation, which would prevent the copper-induced oxidative inactivation of CAT. Copyright © 2011 Elsevier GmbH. All rights reserved.

  4. Catalase improves saccharification of lignocellulose by reducing lytic polysaccharide monooxygenase-associated enzyme inactivation.

    Science.gov (United States)

    Scott, Brian R; Huang, Hong Zhi; Frickman, Jesper; Halvorsen, Rune; Johansen, Katja S

    2016-03-01

    Efficient enzymatic saccharification of plant cell wall material is key to industrial processing of agricultural and forestry waste such as straw and wood chips into fuels and chemicals. Saccharification assays were performed on steam-pretreated wheat straw under ambient and O2-deprived environments and in the absence and presence of a lytic polysaccharide monooxygenase (LPMO) and catalase. A kinetic model was used to calculate catalytic rate and first-order inactivation rate constants of the cellulases from reaction progress curves. The addition of a LPMO significantly (P catalase significantly reduced (P catalase can be used to protect these mixtures from inactivation.

  5. VCP Is an integral component of a novel feedback mechanism that controls intracellular localization of catalase and H2O2 Levels.

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    Katsuhiro Murakami

    Full Text Available Catalase is a key antioxidant enzyme that catalyzes the decomposition of hydrogen peroxide (H2O2 to water and oxygen, and it appears to shuttle between the cytoplasm and peroxisome via unknown mechanisms. Valosin-containing protein (VCP belongs to the AAA class of ATPases and is involved in diverse cellular functions, e.g. cell cycle and protein degradation, etc. Here we show that VCP and PEX19, a protein essential for peroxisome biogenesis, interact with each other. Knockdown of either VCP or PEX19 resulted in a predominantly cytoplasmic redistribution of catalase, and loss of VCP ATPase activity also increased its cytoplasmic redistribution. Moreover, VCP knockdown decreased intracellular ROS levels in normal and H2O2-treated cells, and an oxidation-resistant VCP impaired the ROS-induced cytoplasmic redistribution of catalase. These observations reveal a novel feedback mechanism, in which VCP can sense H2O2 levels, and regulates them by controlling the localization of catalase.

  6. Comportamento da castanha-do-brasil (Bertholletia excelsa e da cupiúba (Goupia glabra em sistema agrosilvicultural na região da Confiança, Cantá - Roraima Behavior of castanha-do-brasil (Bertholletia excelsa and cupiúba (Goupia glabra in an agrosilvicultural system in Confiança region, Cantá - Roraima State

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    Liane Marise Moreira Ferreira

    2009-01-01

    Full Text Available O presente trabalho objetivou estudar o desempenho das espécies castanha-do-brasil (Bertholetia excelsa e cupiúba (Goupia glabra e o ajuste de uma função de crescimento e uma equação para estimar o diâmetro de copa em um modelo de sistema agroflorestal - SAF implantado em 1995 no Campo Experimental Confiança, Cantá, Estado de Roraima. Foram medidas 71 árvores de castanheira e 50 de cupiúbas totalizando 121 árvores, sendo tomados o CAP (circunferência a 1,30 m do solo, altura total, altura de inserção da copa, diâmetro da copa e dados qualitativos como sobrevivência, qualidade do fuste, bifurcações e aspectos fitossanitários como doenças ou pragas. Das 71 árvores de castanheira avaliadas 20 (27,8% produziram frutos. A cupiúba apresentou alta porcentagem de indivíduos com bifurcação (cerca de 87,5%. A análise estatística indicou a função de Backman como a de melhor ajuste para as espécies observadas e com base nas equações construídas para estimar o diâmetro da copa em função do DAP pode-se fazer inferências sobre o espaço vital necessário para atingir uma determinada dimensão. Ambas as espécies apresentaram potencial silvicultural para recuperação de áreas alteradas em sistemas agroflorestais ou plantios homogêneos.The aim of this present work was to study the behavior of castanha-do-brasil (Bertholletia excelsa and cupiúba (Goupia glabra and also set a growing function and an equation for estimating the crown diameter in an agroforestry system model, installed in Confiança Experimental Station, Cantá, Roraima, Brazil, in 1995. We measured quantitative data, such as diameter basal height, total height, crown insertion height, crown diameter and qualitative data like survival, bole quality and phytosanitary aspects such as disease or pests. We analyzed the silvicultural behavior and estimated equation at the crown diameter in function of DBH, and adjusted a growing function for the cupiuba and

  7. Influência de diferentes sombreamentos e nutrição foliar no desenvolvimento de mudas de Palmeiras Ráfia Rhapis excelsa (Thunberg Henry ex. Rehder Influence of differents shading and fertilizer foliar in development of seedlings of lady palm Rhapis excelsa (Thunberg Henry ex. Rehder

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    Antônio José Arantes Meirelles

    2007-12-01

    Full Text Available A palmeira ráfia (Rhapis excelsa, possui elevado valor comercial, sendo utilizada na composição de vasos e jardins, principalmente em interiores. No entanto, poucas são as informações sobre sua exigência em adubação ou mesmo sobre as condições ótimas de sombreamento. Para sombreamento, além do tradicional sombrite, estão disponíveis atualmente no mercado as malhas fotoconversoras, que estimulam o desenvolvimento das espécies vegetais. Objetivou-se nesse trabalho avaliar a influência de diferentes porcentagens e tipos de sombreamentos e a nutrição foliar no desenvolvimento de mudas desta palmeira. Utilizaram-se plantas com aproximadamente 4 anos, em vaso contendo terra, areia e esterco (1:1:1, acrescido de 10 g de superfosfato simples por litro de substrato. Determinou-se o incremento em altura e o número de folhas aos 105 e 195 dias. Foi determinado também o número e altura dos brotos, largura do folíolo e altura final das plantas aos 195 dias. Em relação à adubação foliar, não foi observado efeito dessa sobre o desenvolvimento das mudas. As malhas para sombreamento também não exerceram efeitos significativos na altura final de plantas, indicando que o desenvolvimento das mudas de palmeira ráfia pode ser realizado sob qualquer tipo de sombreamento.Lady palm (Rhapis excelsa has high commercial value, specially in ornaments of vases and gardens located on shade. However, the information about its requirements in fertilizer and great terms of shading are little. To shade, the common used material is shade net black. The color shade net stimulate the vegetal growth and it is recently used in the commercial system. The aim of this work was to evaluate the influence of different percents and types of shades and foliar fertilizer in development of seedlings this palm. The plants used in this experiment were cultivated in recipients with soil, organic matter and sand (1:1:1, with the addition of 10 g of fertilizer by

  8. Regeneración Natural del Roble Negro (Colombobalanus excelsa, Fagaceae en Dos Poblaciones de la Cordillera Oriental de los Andes, Colombia Natural Regeneration of Black Oak (Colombobalanus excelsa, Fagaceae in Two Populations from the Cordillera Oriental of the Colombian Andes

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    César Augusto Parra Aldana

    2011-12-01

    Full Text Available Colombobalanus excelsa es una especie endémica de la zona andina de Colombia, con cuatro poblaciones aisladas que forman rodales homogéneos denominados robledales negros. Se encuentra en categoría vulnerable de amenaza, debido principalmente a la conversión del bosque para usos agropecuarios; observaciones en campo indican que la regeneración natural bajo su propia cobertura es escasa. Se propone responder las siguientes preguntas: 1. ¿La estructura del bosque evidencia deficiencias en la regeneración natural de dos poblaciones de roble negro localizadas en la cordillera oriental de los Andes? 2. ¿El reclutamiento de fhmoreno@unal.edu.co está limitado por la disponibilidad y viabilidad de las semillas en las dos poblaciones estudiadas? Con este objetivo se establecieron 16 transectos permanentes de 0,1 ha para evaluar la estructura de adultos (DAP>10 cm y de la regeneración natural. Durante un año se realizó monitoreo sobre las épocas de fructificación, lluvia de semillas, germinación y banco de semillas. Los resultados muestran un suministro extremadamente bajo de renuevos y propágulos de roble negro, lo cual potencialmente puede poner en riesgo la persistencia de estos bosques. Esta situación obedece a diversos factores involucrados en el proceso de regeneración: desde baja producción de semillas de los árboles adultos, altos niveles de depredación pre-dispersión, alta proporción de semillas vacías, baja viabilidad de las semillas sanas, hasta alta mortalidad de las semillas sanas y viables que llegan al suelo. Si bien todos estos factores actúan en cascada, el último de ellos es quizás el que ejerce un efecto más dramático en el bajo éxito reproductivo de esta especie.Colombobalanus excelsa is an endemic species of the Andean region of Colombia, with four isolated populations, forming pure stands called black oak forests. It has been classified in the threat category ''Vulnerable'', mainly due to conversion of

  9. Characterization of OxyR as a negative transcriptional regulator that represses catalase production in Corynebacterium diphtheriae.

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    Ju-Sim Kim

    Full Text Available Corynebacterium diphtheriae and Corynebacterium glutamicum each have one gene (cat encoding catalase. In-frame Δcat mutants of C. diphtheriae and C. glutamicum were hyper-sensitive to growth inhibition and killing by H(2O(2. In C. diphtheriae C7(β, both catalase activity and cat transcription decreased ~2-fold during transition from exponential growth to early stationary phase. Prototypic OxyR in Escherichia coli senses oxidative stress and it activates katG transcription and catalase production in response to H(2O(2. In contrast, exposure of C. diphtheriae C7(β to H(2O(2 did not stimulate transcription of cat. OxyR from C. diphtheriae and C. glutamicum have 52% similarity with E. coli OxyR and contain homologs of the two cysteine residues involved in H(2O(2 sensing by E. coli OxyR. In-frame ΔoxyR deletion mutants of C. diphtheriae C7(β, C. diphtheriae NCTC13129, and C. glutamicum were much more resistant than their parental wild type strains to growth inhibition by H(2O(2. In the C. diphtheriae C7(β ΔoxyR mutant, cat transcripts were about 8-fold more abundant and catalase activity was about 20-fold greater than in the C7(β wild type strain. The oxyR gene from C. diphtheriae or C. glutamicum, but not from E. coli, complemented the defect in ΔoxyR mutants of C. diphtheriae and C. glutamicum and decreased their H(2O(2 resistance to the level of their parental strains. Gel-mobility shift, DNaseI footprint, and primer extension assays showed that purified OxyR from C. diphtheriae C7(β bound, in the presence or absence of DTT, to a sequence in the cat promoter region that extends from nucleotide position -55 to -10 with respect to the +1 nucleotide in the cat ORF. These results demonstrate that OxyR from C. diphtheriae or C. glutamicum functions as a transcriptional repressor of the cat gene by a mechanism that is independent of oxidative stress induced by H(2O(2.

  10. Ascorbate peroxidase and catalase cooperate for protection against hydrogen peroxide generated in potato tubers during low-temperature storage.

    Science.gov (United States)

    Mizuno, M; Kamei, M; Tsuchida, H

    1998-04-01

    We investigated the behavior of the antioxidant enzymes, superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APx), in potato tubers during storage at low temperature. SOD activity increased temporarily within 3 weeks and was higher at 1 degree C than at 20 degrees C. APx activity also increased more at low (1 degree C) than at higher temperatures (5 and 20 degrees C). The contents of ascorbic acid (AsA), which is the substrate of APx, decreased immediately within 3 weeks and then gradually decreased until 15 weeks. The activity of CAT, the other enzyme which can scavenge hydrogen peroxide, decreased once in the first six weeks and thereafter increased to 15 weeks. Thus, the enhancement of the active oxygen-scavenging system that was induced by low temperature in potato tubers could result not only in a decrease of AsA but also in combined increases in APx and CAT activity whose manners were different.

  11. Sistema de amostragem para quantificar a produção de sementes de Bertholletia excelsa H.B.K (castanha do Brasil) na região de Oriximiná - PA

    OpenAIRE

    Barbeiro, Laercio da Silveira Soares

    2012-01-01

    Orientador : Prof. Dr. Sylvio Péllico Netto Co-orientadora : Profª. Drª. Ana Paula Dalla Côrte Dissertação (mestrado) - Universidade Federal do Paraná, Setor de Ciências Agrárias, Programa de Pós-Graduação em Engenharia Florestal. Defesa: Curitiba, 27/04/2012 Inclui referências Área de concentração : Manejo florestal Resumo: Bertholletia excelsa, conhecida popularmente como castanha do Brasil é uma espécie chave para aliar a conservação e o manejo sustentável da floresta amazôn...

  12. HUMAN CATALASE IS IMPORTED AND ASSEMBLED IN PEROXISOMES OF SACCHAROMYCES-CEREVISIAE

    NARCIS (Netherlands)

    DEHOOP, MJ; HOLTMAN, WL; AB, G

    To study the conservation of peroxisomal targeting signals, we have determined the intracellular localization of human peroxisomal catalase when expressed in yeast. Using immunofluorescence, differential centrifugation and immuno-electron microscopy, we show that the protein is targeted to the

  13. Elevated catalase expression in a fungal pathogen is a double-edged sword of iron.

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    Arnab Pradhan

    2017-05-01

    Full Text Available Most fungal pathogens of humans display robust protective oxidative stress responses that contribute to their pathogenicity. The induction of enzymes that detoxify reactive oxygen species (ROS is an essential component of these responses. We showed previously that ectopic expression of the heme-containing catalase enzyme in Candida albicans enhances resistance to oxidative stress, combinatorial oxidative plus cationic stress, and phagocytic killing. Clearly ectopic catalase expression confers fitness advantages in the presence of stress, and therefore in this study we tested whether it enhances fitness in the absence of stress. We addressed this using a set of congenic barcoded C. albicans strains that include doxycycline-conditional tetON-CAT1 expressors. We show that high basal catalase levels, rather than CAT1 induction following stress imposition, reduce ROS accumulation and cell death, thereby promoting resistance to acute peroxide or combinatorial stress. This conclusion is reinforced by our analyses of phenotypically diverse clinical isolates and the impact of stochastic variation in catalase expression upon stress resistance in genetically homogeneous C. albicans populations. Accordingly, cat1Δ cells are more sensitive to neutrophil killing. However, we find that catalase inactivation does not attenuate C. albicans virulence in mouse or invertebrate models of systemic candidiasis. Furthermore, our direct comparisons of fitness in vitro using isogenic barcoded CAT1, cat1Δ and tetON-CAT1 strains show that, while ectopic catalase expression confers a fitness advantage during peroxide stress, it confers a fitness defect in the absence of stress. This fitness defect is suppressed by iron supplementation. Also high basal catalase levels induce key iron assimilatory functions (CFL5, FET3, FRP1, FTR1. We conclude that while high basal catalase levels enhance peroxide stress resistance, they place pressure on iron homeostasis through an

  14. Elevated catalase expression in a fungal pathogen is a double-edged sword of iron.

    Science.gov (United States)

    Pradhan, Arnab; Herrero-de-Dios, Carmen; Belmonte, Rodrigo; Budge, Susan; Lopez Garcia, Angela; Kolmogorova, Aljona; Lee, Keunsook K; Martin, Brennan D; Ribeiro, Antonio; Bebes, Attila; Yuecel, Raif; Gow, Neil A R; Munro, Carol A; MacCallum, Donna M; Quinn, Janet; Brown, Alistair J P

    2017-05-01

    Most fungal pathogens of humans display robust protective oxidative stress responses that contribute to their pathogenicity. The induction of enzymes that detoxify reactive oxygen species (ROS) is an essential component of these responses. We showed previously that ectopic expression of the heme-containing catalase enzyme in Candida albicans enhances resistance to oxidative stress, combinatorial oxidative plus cationic stress, and phagocytic killing. Clearly ectopic catalase expression confers fitness advantages in the presence of stress, and therefore in this study we tested whether it enhances fitness in the absence of stress. We addressed this using a set of congenic barcoded C. albicans strains that include doxycycline-conditional tetON-CAT1 expressors. We show that high basal catalase levels, rather than CAT1 induction following stress imposition, reduce ROS accumulation and cell death, thereby promoting resistance to acute peroxide or combinatorial stress. This conclusion is reinforced by our analyses of phenotypically diverse clinical isolates and the impact of stochastic variation in catalase expression upon stress resistance in genetically homogeneous C. albicans populations. Accordingly, cat1Δ cells are more sensitive to neutrophil killing. However, we find that catalase inactivation does not attenuate C. albicans virulence in mouse or invertebrate models of systemic candidiasis. Furthermore, our direct comparisons of fitness in vitro using isogenic barcoded CAT1, cat1Δ and tetON-CAT1 strains show that, while ectopic catalase expression confers a fitness advantage during peroxide stress, it confers a fitness defect in the absence of stress. This fitness defect is suppressed by iron supplementation. Also high basal catalase levels induce key iron assimilatory functions (CFL5, FET3, FRP1, FTR1). We conclude that while high basal catalase levels enhance peroxide stress resistance, they place pressure on iron homeostasis through an elevated cellular demand

  15. Revealing mechanisms of selective, concentration-dependent potentials of 4-hydroxy-2-nonenal to induce apoptosis in cancer cells through inactivation of membrane-associated catalase.

    Science.gov (United States)

    Bauer, Georg; Zarkovic, Neven

    2015-04-01

    Tumor cells generate extracellular superoxide anions and are protected against superoxide anion-mediated intercellular apoptosis-inducing signaling by the expression of membrane-associated catalase. 4-Hydroxy-2-nonenal (4-HNE), a versatile second messenger generated during lipid peroxidation, has been shown to induce apoptosis selectively in malignant cells. The findings described in this paper reveal the strong, concentration-dependent potential of 4-HNE to specifically inactivate extracellular catalase of tumor cells both indirectly and directly and to consequently trigger apoptosis in malignant cells through superoxide anion-mediated intercellular apoptosis-inducing signaling. Namely, 4-HNE caused apoptosis selectively in NOX1-expressing tumor cells through inactivation of their membrane-associated catalase, thus reactivating subsequent intercellular signaling through the NO/peroxynitrite and HOCl pathways, followed by the mitochondrial pathway of apoptosis. Concentrations of 4-HNE of 1.2 µM and higher directly inactivated membrane-associated catalase of tumor cells, whereas at lower concentrations, 4-HNE triggered a complex amplificatory pathway based on initial singlet oxygen formation through H2O2 and peroxynitrite interaction. Singlet-oxygen-dependent activation of the FAS receptor and caspase-8 increased superoxide anion generation by NOX1 and amplification of singlet oxygen generation, which allowed singlet-oxygen-dependent inactivation of catalase. 4-HNE and singlet oxygen cooperate in complex autoamplificatory loops during this process. The finding of these novel anticancer pathways may be useful for understanding the role of 4-HNE in the control of malignant cells and for the optimization of ROS-dependent therapeutic approaches including antioxidant treatments. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Cytotoxic and antioxidant capacity of camel milk peptides: Effects of isolated peptide on superoxide dismutase and catalase gene expression

    Directory of Open Access Journals (Sweden)

    Masoud Homayouni-Tabrizi

    2017-07-01

    Full Text Available Peptides from natural sources such as milk are shown to have a wide spectrum of biological activities. In this study, three peptides with antioxidant capacity were identified from camel milk protein hydrolysate. Pepsin and pancreatin were used for hydrolysis of milk proteins. Ultrafiltration and reverse-phase high-performance liquid chromatography were used for the concentration and purification of the hydrolysate, respectively. Sequences of the three peptides, which were determined by matrix-assisted laser desorption/ionization time-of-flight spectrophotometry, were LEEQQQTEDEQQDQL [molecular weight (MW: 1860.85 Da, LL-15], YLEELHRLNAGY (MW: 1477.63 Da, YY-11, and RGLHPVPQ (MW: 903.04 Da, RQ-8. The 3-(4,5-dimethylthia-zol-2-yl-2,5-diphenyltetrazolium bromide assay was used to evaluate the cytotoxicity of these chemically synthesized peptides against HepG2 cells. In vitro analysis showed antioxidant properties and radical scavenging activities of these peptides on 2,2-diphenyl-1-picrylhydrazyl, 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid+, O2–, and OH– free radicals. HepG2 cells were treated with YY-11 peptide for 48 hours, and the expression of superoxide dismutase and catalase genes was examined using real-time polymerase chain reaction. The results revealed a significant increase in the expression of superoxide dismutase and catalase genes in treated HepG2 cells.

  17. Wild-type catalase peroxidase vs G279D mutant type: Molecular basis of Isoniazid drug resistance in Mycobacterium tuberculosis.

    Science.gov (United States)

    Singh, Aishwarya; Singh, Aditi; Grover, Sonam; Pandey, Bharati; Kumari, Anchala; Grover, Abhinav

    2018-01-30

    Mycobacterium tuberculosis katG gene is responsible for production of an enzyme catalase peroxidase that peroxidises and activates the prodrug Isoniazid (INH), a first-line antitubercular agent. INH interacts with catalase peroxidase enzyme within its heme pocket and gets converted to an active form. Mutations occurring in katG gene are often linked to reduced conversion rates for INH. This study is focussed on one such mutation occurring at residue 279, where glycine often mutates to aspartic acid (G279D). In the present study, several structural analyses were performed to study the effect of this mutation on functionality of KatG protein. On comparison, mutant protein exhibited a lower docking score, smaller binding cavity and reduced affinity towards INH. Molecular dynamics analysis revealed the mutant to be more rigid and less compact than the native protein. Essential dynamics analysis determined correlated motions of residues within the protein structure. G279D mutant was found to have many residues that showed related motions and an undesirable effect on the functionality of protein. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Comparison of Lipid Peroxidation and Catalase Response in Invasive Dreissenid Mussels Exposed to Single and Multiple Stressors.

    Science.gov (United States)

    Nowicki, Carly J; Kashian, Donna R

    2018-02-14

    Dreissenid mussels, Dreissena bugensis (quagga mussel) and D. polymorpha (zebra mussel), are prolific invasive species to the freshwaters of the United States and Western Europe. In the Great Lakes, D. polymorpha initially dominated the system since their invasion in the mid-1980 s; however, recently D. bugensis has displaced D. polymorpha as the dominant species. Dreissena bugensis has several competitive advantages over D. polymorpha, including greater tolerances to deeper and colder waters and lower respiration rates. However, physiological differences between the species remain largely unknown. The oxidative stress response is a mechanism used by all organisms to mitigate environmental stress by reducing oxygen radicals in the body, and comparing this mechanism between similar species can be a useful for understanding how different species compete in aquatic environments. We compared oxidative stress biomarkers (lipid peroxidation and catalase activity) in mussels following exposure to four stressors (e.g., high densities, temperature, hypoxia, and polychlorinated biphenyls) independently and in combinations of two stressors. Overall, D. bugensis had lower lipid peroxidation and catalase activity than D. polymorpha when exposed to single stressors; however, in multiple stressors treatments D. bugensis had increased lipid peroxidation, especially with high temperatures and PCBs. The lower lipid damage in D. bugensis compared to D. polymorpha under single stressor conditions may come at the cost of the ability to respond to multiple stressors. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  19. Isolation and characterization of a catalase gene "HuCAT3" from pitaya (Hylocereus undatus) and its expression under abiotic stress.

    Science.gov (United States)

    Nie, Qiong; Gao, Guo-Li; Fan, Qing-jie; Qiao, Guang; Wen, Xiao-Peng; Liu, Tao; Peng, Zhi-Jun; Cai, Yong-Qiang

    2015-05-25

    Abiotic stresses usually cause H2O2 accumulation, with harmful effects, in plants. Catalase may play a key protective role in plant cells by detoxifying this excess H2O2. Pitaya (Hylocereus undatus) shows broad ecological adaptation due to its high tolerance to abiotic stresses, e.g. drought, heat and poor soil. However, involvement of the pitaya catalase gene (HuCAT) in tolerance to abiotic stresses is unknown. In the present study, a full-length HuCAT3 cDNA (1870 bp) was isolated from pitaya based on our previous microarray data and RACE method. The cDNA sequence and deduced amino acid sequence shared 73-77% and 75-80% identity with other plant catalases, respectively. HuCAT3 contains conserved catalase family domain and catalytic sites. Pairwise comparison and phylogenetic analysis indicated that HuCAT3 is most similar to Eriobotrya japonica CAT, followed by Dimocarpus longan CAT and Nicotiana tabacum CAT1. Expression profile analysis demonstrated that HuCAT3 is mainly expressed in green cotyledons and mature stems, and was regulated by H2O2, drought, cold and salt stress, whereas, its expression patterns and maximum expression levels varied with stress types. HuCAT activity increased as exposure to the tested stresses, and the fluctuation of HuCAT activity was consistent with HuCAT3 mRNA abundance (except for 0.5 days upon drought stress). HuCAT3 mRNA elevations and HuCAT activities changes under cold stress were also in conformity with the cold tolerances among the four genotypes. The obtained results confirmed a major role of HuCAT3 in abiotic stress response of pitaya. This may prove useful in understanding pitaya's high tolerance to abiotic stresses at molecular level. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. The oxidation of chiral alcohols catalyzed by catalase in organic solvents

    Energy Technology Data Exchange (ETDEWEB)

    Magner, E.; Klibanov, A.M. [Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Chemistry

    1995-04-20

    The catalytic properties of bovine liver catalase have been investigated in organic solvents. In tetrahydrofuran, dioxane, and acetone (all containing 1% to 3% of water), the enzyme breaks down tert-butyl hydroperoxide several fold faster than in pure water. Furthermore, the rate of catalase-catalyzed production of tert-butanol from tert-butyl hydroperoxide increases more than 400-fold upon transition from aqueous buffer to ethanol as the reaction medium. The mechanistic rationale for this striking effect is that in aqueous buffer the rate-limiting step of the enzymatic process involves the reduction of catalase`s compound 1 by tert-butyl hydroperoxide. In ethanol, an additional step in the reaction scheme becomes available in which ethanol, greatly outcompeting the hydroperoxide, is oxidized by compound 1 regenerating the free enzyme. In solvents, such as acetonitrile or tetrahydrofuran, which themselves are not oxidizable by compound 1, catalase catalyzes the oxidation of numerous primary and secondary alcohols with tert-butyl hydroperoxide to the corresponding aldehydes or ketones. The enzymatic oxidation of some chiral alcohols (2,3-butanediol, citronellol, and menthol) under these conditions occurs enantioselectively. Examination of the enantioselectivity for the oxidation of 2,3-butanediol in a series of organic solvents reveals a considerable solvent dependence.

  1. Targeting catalase but not peroxiredoxins enhances arsenic trioxide-induced apoptosis in K562 cells.

    Directory of Open Access Journals (Sweden)

    Li-Li Song

    Full Text Available Despite considerable efficacy of arsenic trioxide (As2O3 in acute promyelocytic leukemia (APL treatment, other non-APL leukemias, such as chronic myeloid leukemia (CML, are less sensitive to As2O3 treatment. However, the underlying mechanism is not well understood. Here we show that relative As2O3-resistant K562 cells have significantly lower ROS levels than As2O3-sensitive NB4 cells. We compared the expression of several antioxidant enzymes in these two cell lines and found that peroxiredoxin 1/2/6 and catalase are expressed at high levels in K562 cells. We further investigated the possible role of peroxirdoxin 1/2/6 and catalase in determining the cellular sensitivity to As2O3. Interestingly, knockdown of peroxiredoxin 1/2/6 did not increase the susceptibility of K562 cells to As2O3. On the contrary, knockdown of catalase markedly enhanced As2O3-induced apoptosis. In addition, we provide evidence that overexpression of BCR/ABL cannot increase the expression of PRDX 1/2/6 and catalase. The current study reveals that the functional role of antioxidant enzymes is cellular context and treatment agents dependent; targeting catalase may represent a novel strategy to improve the efficacy of As2O3 in CML treatment.

  2. Catalase, a remarkable enzyme: targeting the oldest antioxidant enzyme to find a new cancer treatment approach.

    Science.gov (United States)

    Glorieux, Christophe; Calderon, Pedro Buc

    2017-09-26

    This review is centered on the antioxidant enzyme catalase and will present different aspects of this particular protein. Among them: historical discovery, biological functions, types of catalases and recent data with regard to molecular mechanisms regulating its expression. The main goal is to understand the biological consequences of chronic exposure of cells to hydrogen peroxide leading to cellular adaptation. Such issues are of the utmost importance with potential therapeutic extrapolation for various pathologies. Catalase is a key enzyme in the metabolism of H2O2 and reactive nitrogen species, and its expression and localization is markedly altered in tumors. The molecular mechanisms regulating the expression of catalase, the oldest known and first discovered antioxidant enzyme, are not completely elucidated. As cancer cells are characterized by an increased production of reactive oxygen species (ROS) and a rather altered expression of antioxidant enzymes, these characteristics represent an advantage in terms of cell proliferation. Meanwhile, they render cancer cells particularly sensitive to an oxidant insult. In this context, targeting the redox status of cancer cells by modulating catalase expression is emerging as a novel approach to potentiate chemotherapy.

  3. Evaluation of Salivary Vitamin C and Catalase in HIV Positive and Healthy HIV Negative Control Group.

    Science.gov (United States)

    Ahmadi-Motamayel, Fatemeh; Vaziri-Amjad, Samaneh; Goodarzi, Mohammad Taghi; Poorolajal, Jalal

    2017-01-01

    Saliva is a complex oral biologic fluid secreted by major and minor salivary glands. Saliva has immunological, enzymatic and antioxidant defense mechanisms. Infection with human immunodeficiency virus (HIV) is a life-threatening disease. The aim of this study was to evaluate salivary vitamin C and catalase levels in HIV-positive patients in comparison to a healthy control group. Forty-nine HIV-infected individuals and 49 healthy subjects were selected. Five mL of unstimulated saliva was collected in 5 minutes using a sterilized Falcon tube with Navazesh method. Catalase and vitamin C levels were assessed by spectrophotometric assay. Data were analyzed with STATA 12. Salivary catalase levels were 7.99±2.40 and 8.37±1.81 in the case and control groups, respectively. Catalase level was lower in the case group but the difference was not statistically significant (P=0.380). Salivary vitamin C levels in the case and control groups were 3.76±1.92 and 4.87±2.20, respectively (P=0.009). HIV can alter salivary antioxidant capacity as well as vitamin C and catalase levels. Saliva may reflect serum antioxidative changes in these patients. Therefore, further research is necessary on salivary and serum oxidants and the antioxidant changes. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  4. Bioaccumulation of fullerene (C60) and corresponding catalase elevation in Lumbriculus variegatus.

    Science.gov (United States)

    Wang, Jiafan; Wages, Mike; Yu, Shuangying; Maul, Jonathan D; Mayer, Greg; Hope-Weeks, Louisa; Cobb, George P

    2014-05-01

    Fullerene (C(60)), with its unique physical properties and nanometer size, has been mass-produced for many applications in recent decades. The increased likelihood of direct release into the environment has raised interest in understanding both the environmental fate and corresponding biological effects of fullerenes to living organisms. Because few studies have emphasized fullerene uptake and resulting biochemical responses by living organisms, a toxicity screening test and a 28-d bioaccumulation test for Lumbriculus variegatus were performed. No mortality was observed in the range of 0.05 mg C(60) /kg dry sediment to 11.33 mg C(60) /kg dry sediment. A biota-sediment accumulation factor of micron-sized fullerene agglomerates (µ-C(60)) was 0.032 ± 0.008 at day 28, which is relatively low compared with pyrene (1.62 ± 0.22). Catalase (CAT) activity, an oxidative stress indicator, was elevated significantly on day 14 for L. variegatus exposed to µ-C(60) (p = 0.034). This peak CAT activity corresponded to the highest body residues observed in the present study, 199 ± 80 µg C(60) /kg dry weight sediment. Additionally, smaller C(60) agglomerate size increased bioaccumulation potential in L. variegatus. The relationship between C(60) body residue and the increased CAT activity followed a linear regression. All results suggest that C(60) has a lower bioaccumulation potential than pyrene but a higher potential to induce oxidative stress in L. variegatus. © 2014 SETAC.

  5. Catalase inhibition accelerates dormancy release and sprouting in potato (Solanum tuberosum L. tubers

    Directory of Open Access Journals (Sweden)

    Mohammed Bajji

    2007-01-01

    Full Text Available The involvement of hydrogen peroxide (H2O2 metabolism in dormancy release and sprouting of potato (Solanum tuberosum L. tubers has been investigated using three complementary approaches. In the first approach, the evolution of the sprouting kinetics, H2O2 content and antioxidant enzyme activities were examined during tuber storage. The most important changes occurred at the « bud/sprout » level. In particular, dormancy release was accompanied by a transient but remarkable increase in H2O2 content. In the second approach, the effect of a catalase (CAT, EC 1.11.1.6 inhibitor (thiourea or of exogenous H2O2 application on tuber sprouting behaviour was assessed. Both treatments resulted in a reduction of the dormancy period and in rapid and synchronised sprouting of the treated tubers when compared to the control as well as in increased sprout number per tuber. In the third approach, the effect of CAT inhibition on potato tuber dormancy and sprouting was evaluated using the transgenic technology. Plants partially repressed in their CAT activity were produced and, once again, CAT inhibition resulted in acceleration of the sprouting kinetics and in increased sprout number of the transgenic tubers compared to those from the wild type. It thus appears that tuber dormancy and sprouting can be controlled in potato by the manipulation of H2O2 metabolism via the inhibition of CAT activity. The possible mechanisms whereby CAT inhibitors or H2O2 overcome dormancy and promote sprouting in the potato tuber are discussed in relation to what is known in other plant models (seeds and fruit tree buds.

  6. Study on the role of catalase for uptake of metallic mercury Part 3 In vitro oxidation of metallic mercury by catalase and hydrogen peroxide generated by several oxidase system

    OpenAIRE

    劒持,堅志

    1984-01-01

    In vitro oxidation of metallic mercury by catalase and hydrogen peroxide generated by the glucose-glucose oxidase system, D-alanine-D-amino acid oxidase system and xanthine-xanthine oxidase-superoxide dismutase system was investigated. In vitro oxidation of metallic mercury by catalase and hydrogen peroxide generated by the reaction with glucose and glucose oxidase was observed in erythrocytes and crystalline beef liver catalase solution. The uptake depended on the concentration of glucose ox...

  7. Morphometric characterisation of solitary trees of Bertholletia excelsa H.B.K. In the southeast Roraima = Caracterização morfométrica de árvores solitárias de Bertholletia excelsa H.B.K. no sudeste de Roraima

    Directory of Open Access Journals (Sweden)

    Luiz Fernandes Silva Dionisio

    2017-06-01

    Full Text Available In order to manage native forest species, it is necessary to know both the characteristics and dynamics of the trees over time, as well as their morphometric relationship to improve silvicultural techniques. The aim of this study was to evaluate the morphometric characteristics of solitary Brazil nut trees (Bertholletia excelsa H.B.K, in the towns of São João da Baliza and Caroebe, in the State of Roraima. The inventory evaluated 49 individuals with a diameter at breast height (DAP ≥10 cm. The following morphometric variables were evaluated: diameter at breast height, measured 1.30 m from ground level; total height (HT, commercial trunk height (HC; crown diameter (DC, crown length (CC, crown ratio (PC, crown area (AC, degree of slenderness (GE, salience index (s, crown cover index (ia and crown shape index (fc. To study interdimensional relationships, the morphometric variables were related to the DAP using regression analysis. It was found that 32.9% of individuals presented a mean value for ht of 16.05 m and a DAP of 49.75 cm, with values for ac, cc and pc of 12.61 m2 , 8.18 m and 51.29 m respectively. The results showed a statistically significant relationship between DAP and HT, CC, PC, IS, FC and AC. The length, crown ratio and crown diameter showed a wide range of variation. The crown shape revealed that Brazil nut trees have crowns that are more elongated. It is possible to fit the significant mathematical models as a function of DAP. More-efficient measures are needed to ensure the full protection of these isolated individuals. = Para manejar espécies florestais nativas, é necessário conhecer tanto as características quanto a dinâmica das árvores ao longo do tempo, bem como suas relações morfométricas a fim de aperfeiçoar as técnicas silviculturais. Assim, objetivou-se com o presente trabalho avaliar as características morfométricas de árvores solitárias de castanheira-do-brasil (Bertholletia excelsa H.B.K, nos munic

  8. Desenvolvimento de Rhapis excelsa (Thunberg Henry Ex. Rehder (Palmeira-Ráfia: Influência da altura do recipiente na formação de mudas Development of Rhapis excelsa (Thunberg Henry Ex. Rehder (Palm-Ráfia: influence of the height of the recipient in the formation of seedlings

    Directory of Open Access Journals (Sweden)

    Petterson Baptista da Luz

    2006-02-01

    Full Text Available Rhapis excelsa, originária do sul da China, é uma das palmeiras ornamentais mais cultivadas no mundo, principalmente em vaso. Objetivou-se com esta pesquisa investigar a influência da altura do vaso no desenvolvimento da espécie. Para tanto, mudas de dois anos de idade, apresentando 10 cm de altura e sistema radicular com 10 cm de comprimento, foram transplantadas para recipientes de PVC com 10 cm de diâmetro e 20, 25, 30, 35 e 40 cm de altura, que se constituíram em tratamentos. O substrato utilizado foi uma mistura de casca de pinho, vermiculita e solo argiloso (2:1:1, adubado com 45 g de Osmocote (15:10:10. Os parâmetros avaliados foram: altura da planta, diâmetro do colo, número de folhas, número de perfilhos emitidos, avaliados aos 6, 12 e 18 meses após a instalação do experimento. Aos 18 meses foram tomados também o peso da matéria seca da parte aérea e o peso da matéria seca das raízes. O delineamento experimental foi inteiramente casualizado, com cinco repetições com duas plantas. Houve diferença significativa para a variável altura de plantas, aos 6 meses, sendo que o recipiente de 40 cm de altura apresentou o pior resultado. Não houve diferença significativa entre as variáveis analisadas aos 12 meses de investigação. Já aos 18 meses, houve diferenças significativas entre os tratamentos para as variáveis altura da planta e diâmetro do colo, sendo o recipiente de 40 cm inferior aos demais em relação à altura da planta e o de 25 cm superior quanto ao diâmetro do colo. A utilização do recipiente com 25 cm de altura revelou-se interessante pela qualidade das plantas formadas e em relação a aspectos econômicos da produção.Rhapis excelsa is one the most important ornamental palm cultivated in the world, mainly as vase plant, being indigenous to China. The aim of this research was to investigate the influence of vase height on the development of the species. Two years-old seedlings with 10 cm height

  9. PprM is necessary for up-regulation of katE1, encoding the major catalase of Deinococcus radiodurans, under unstressed culture conditions.

    Science.gov (United States)

    Jeong, Sun-Wook; Seo, Ho Seong; Kim, Min-Kyu; Choi, Jong-Il; Lim, Heon-Man; Lim, Sangyong

    2016-06-01

    Deinococcus radiodurans is a poly-extremophilic organism, capable of tolerating a wide variety of different stresses, such as gamma/ultraviolet radiation, desiccation, and oxidative stress. PprM, a cold shock protein homolog, is involved in the radiation resistance of D. radiodurans, but its role in the oxidative stress response has not been investigated. In this study, we investigated the effect of pprM mutation on catalase gene expression. pprM disruption decreased the mRNA and protein levels of KatE1, which is the major catalase in D. radiodurans, under normal culture conditions. A pprM mutant strain (pprM MT) exhibited decreased catalase activity, and its resistance to hydrogen peroxide (H2O2) decreased accordingly compared with that of the wild-type strain. We confirmed that RecG helicase negatively regulates katE1 under normal culture conditions. Among katE1 transcriptional regulators, the positive regulator drRRA was not altered in pprM (-), while the negative regulators perR, dtxR, and recG were activated more than 2.5-fold in pprM MT. These findings suggest that PprM is necessary for KatE1 production under normal culture conditions by down-regulation of katE1 negative regulators.

  10. Environmental Lead Exposure, Catalase Gene, and Markers of Antioxidant and Oxidative Stress Relation to Hypertension: An Analysis Based on the EGAT Study

    Science.gov (United States)

    Kaojarern, Sukhumpun; Chanprasertyothin, Suwannee; Panpunuan, Pachara; Petchpoung, Krittaya; Tatsaneeyapant, Aninthita; Yoovathaworn, Krongtong; Sura, Thunyachai; Kaojarern, Sming; Sritara, Piyamit

    2015-01-01

    Lead has been linked to the development of hypertension via oxidative stress. Catalase plays an important role in the disposal of hydrogen peroxide in erythrocyte and its activity was determined by CAT gene. The aims of this study were to investigate (1) the association between blood levels of antioxidant markers such as catalase, superoxide dismutase, glutathione, glutathione peroxidase, oxidative stress-marker (malondialdehyde), and blood lead level and (2) the influence of genetic polymorphism of CAT gene (rs769217) on change in blood pressure in general population of EGAT study project. This is a cross-sectional study of 332 normotensive, 432 prehypertensive, and 222 hypertensive male subjects. Hypertensive subjects had significantly higher blood lead level (5.28 μg/dL) compared to normotensive (4.41 μg/dL) and prehypertensive (4.55 μg/dL) subjects (P < 0.05). These significant findings are also found in MDA levels. Moreover, individuals with TT genotype in hypertensive group had significantly higher blood lead and MDA levels (6.06 μg/dL and 9.67 μmol/L) than those with CC genotype (5.32 μg/dL and 8.31 μmol/L, P < 0.05). Our findings suggested that decreased blood catalase activity in this polymorphism together with low level lead exposure induced lipid peroxidation may be responsible for hypertension. PMID:25793211

  11. Induction of Viable but Nonculturable Salmonella in Exponentially Grown Cells by Exposure to a Low-Humidity Environment and Their Resuscitation by Catalase.

    Science.gov (United States)

    Morishige, Yuta; Koike, Atsushi; Tamura-Ueyama, Ai; Amano, Fumio

    2017-02-01

    Salmonella is a major cause of foodborne disease that sometimes occurs in massive outbreaks around the world. This pathogen is tolerant of low-humidity conditions. We previously described a method for induction of viable but nonculturable (VBNC) Salmonella enterica serovar Enteritidis by treatment with hydrogen peroxide (H2O2) and subsequent resuscitation with 0.3 mM sodium pyruvate. Here, we report a new method for the induction of the VBNC state in Salmonella Enteritidis cells, one involving dehydration. Exposure of Salmonella Enteritidis cells to dehydration stress under poor nutritional conditions (0.9% [wt/vol] NaCl) and 10 to 20% relative humidity at room temperature decreased the presence of culturable population to 0.0067%, but respiratory and glucose uptake active populations were maintained at 0.46 and 1.12%, respectively, meaning that approximately 1% may have entered the VBNC state. Furthermore, these VBNC cells could be resuscitated to acquire culturability by incubation with catalase in M9 minimal medium without glucose in a manner dependent on the dose of catalase but not sodium pyruvate. These results suggest that a low-humidity environment could cause Salmonella Enteritidis cells to enter the VBNC state and the cells could then be resuscitated for growth by treatment with catalase, suggesting a potential risk of Salmonella Enteritidis to survive in low water activity foods in the VBNC state and to start regrowth for foodborne illness.

  12. Insights into the selective binding and toxic mechanism of microcystin to catalase

    Science.gov (United States)

    Hu, Yuandong; Da, Liangjun

    2014-03-01

    Microcystin is a sort of cyclic nonribosomal peptides produced by cyanobacteria. It is cyanotoxin, which can be very toxic for plants and animals including humans. The present study evaluated the interaction of microcystin and catalase, under physiological conditions by means of fluorescence, three-dimensional (3D) fluorescence, circular dichroism (CD), Fourier Transform infrared (FT-IR) spectroscopy, and enzymatic reactionkinetic techniques. The fluorescence data showed that microcystin could bind to catalase to form a complex. The binding process was a spontaneous molecular interaction procedure, in which electrostatic interactions played a major role. Energy transfer and fluorescence studies proved the existence of a static binding process. Additionally, as shown by the three-dimensional fluorescence, CD and FT-IR results, microcystin could lead to conformational and microenvironmental changes of the protein, which may affect the physiological functions of catalase. The work provides important insights into the toxicity mechanism of microcystin in vivo.

  13. Catalase-dependent H2O2 consumption by cardiac mitochondria and redox-mediated loss in insulin signaling.

    Science.gov (United States)

    Rindler, Paul M; Cacciola, Angela; Kinter, Michael; Szweda, Luke I

    2016-11-01

    We have recently demonstrated that catalase content in mouse cardiac mitochondria is selectively elevated in response to high dietary fat, a nutritional state associated with oxidative stress and loss in insulin signaling. Catalase and various isoforms of glutathione peroxidase and peroxiredoxin each catalyze the consumption of H2O2 Catalase, located primarily within peroxisomes and to a lesser extent mitochondria, has a low binding affinity for H2O2 relative to glutathione peroxidase and peroxiredoxin. As such, the contribution of catalase to mitochondrial H2O2 consumption is not well understood. In the current study, using highly purified cardiac mitochondria challenged with micromolar concentrations of H2O2, we found that catalase contributes significantly to mitochondrial H2O2 consumption. In addition, catalase is solely responsible for removal of H2O2 in nonrespiring or structurally disrupted mitochondria. Finally, in mice fed a high-fat diet, mitochondrial-derived H2O2 is responsible for diminished insulin signaling in the heart as evidenced by reduced insulin-stimulated Akt phosphorylation. While elevated mitochondrial catalase content (∼50%) enhanced the capacity of mitochondria to consume H2O2 in response to high dietary fat, the selective increase in catalase did not prevent H2O2-induced loss in cardiac insulin signaling. Taken together, our results indicate that mitochondrial catalase likely functions to preclude the formation of high levels of H2O2 without perturbing redox-dependent signaling. Copyright © 2016 the American Physiological Society.

  14. Some Aspects of Catalase Induction in Baker's Yeast (Saccharomyces cerevisiae)

    Science.gov (United States)

    Freeland, P. W.

    1974-01-01

    Described are experiments for demonstrating essential features of substrate-induced enzyme synthesis based on the Jacob-Monod model, and for showing that the activity of certain genes can be modified by environmental temperature. (RH)

  15. Isolation and characterization of a novel catalase-negative, urease-positive Campylobacter from cattle faeces

    DEFF Research Database (Denmark)

    Atabay, H.I.; Corry, J.E.L.; On, S.L.W.

    1997-01-01

    characteristics typical for Campylobacter species. However, they were unusual in that they produced urease and copious H2S in triple sugar iron (TSI) medium, but did not produce catalase. They did not grow aerobically. None of the strains grew on modified cefoperazone charcoal deoxycholate agar (m......CCDA). Macrorestriction profiles of chromosomal DNA were prepared for 15 strains using pulsed-field gel electrophoresis (PFGE). Twelve of 15 profiles were identical and all appeared to be closely related. These catalase-negative, urease-positive campylobacters (CNUPC) represent a group not previously reported...

  16. Extraction of superoxide dismutase, catalase, and carbonic anhydrase from stroma-free red blood cell hemolysate for the preparation of the nanobiotechnological complex of polyhemoglobin-superoxide dismutase-catalase-carbonic anhydrase.

    Science.gov (United States)

    Guo, C; Gynn, M; Chang, T M S

    2015-06-01

    We report a novel method to simultaneously extract superoxide dismutase (SOD), catalase (CAT), and carbonic anhydrase (CA) from the same sample of red blood cells (RBCs). This avoids the need to use expensive commercial enzymes, thus enabling a cost-effective process for large-scale production of a nanobiotechnological polyHb-SOD-CAT-CA complex, with enhancement of all three red blood cell functions. An optimal concentration of phosphate buffer for ethanol-chloroform treatment results in good recovery of CAT, SOD, and CA after extraction. Different concentrations of the enzymes can be used to enhance the activity of polyHb-SOD-CAT-CA to 2, 4, or 6 times that of RBC.

  17. Spectroscopic and kinetic investigation of the reactions of peroxyacetic acid with Burkholderia pseudomallei catalase-peroxidase, KatG.

    Science.gov (United States)

    Ivancich, Anabella; Donald, Lynda J; Villanueva, Jacylyn; Wiseman, Ben; Fita, Ignacio; Loewen, Peter C

    2013-10-15

    Catalase-peroxidases or KatGs can utilize organic peroxyacids and peroxides instead of hydrogen peroxide to generate the high-valent ferryl-oxo intermediates involved in the catalase and peroxidase reactions. In the absence of peroxidatic one-electron donors, the ferryl intermediates generated with a low excess (10-fold) of peroxyacetic acid (PAA) slowly decay to the ferric resting state after several minutes, a reaction that is demonstrated in this work by both stopped-flow UV-vis absorption measurements and EPR spectroscopic characterization of Burkholderia pseudomallei KatG (BpKatG). EPR spectroscopy showed that the [Fe(IV)═O Trp330(•+)], [Fe(IV)═O Trp139(•)], and [Fe(IV)═O Trp153(•)] intermediates of the peroxidase-like cycle of BpKatG ( Colin, J. Wiseman, B. Switala, J. Loewen, P. C. Ivancich, A. ( 2009 ) J. Am. Chem. Soc. 131 , 8557 - 8563 ), formed with a low excess of PAA at low temperature, are also generated with a high excess (1000-fold) of PAA at room temperature. However, under high excess conditions, there is a rapid conversion to a persistent [Fe(IV)═O] intermediate. Analysis of tryptic peptides of BpKatG by mass spectrometry before and after treatment with PAA showed that specific tryptophan (including W330, W139, and W153), methionine (including Met264 of the M-Y-W adduct), and cysteine residues are either modified with one, two, or three oxygen atoms or could not be identified in the spectrum because of other undetermined modifications. It was concluded that these oxidized residues were the source of electrons used to reduce the excess of PAA to acetic acid and return the enzyme to the ferric state. Treatment of BpKatG with PAA also caused a loss of catalase activity towards certain substrates, consistent with oxidative disruption of the M-Y-W adduct, and a loss of peroxidase activity, consistent with accumulation of the [Fe(IV)═O] intermediate and the oxidative modification of the W330, W139, and W153. PAA, but not H2O2 or tert

  18. Functional analysis of an extracellular catalase of Botrytis cinerea

    NARCIS (Netherlands)

    Schouten, A.; Tenberge, K.B.; Vermeer, J.; Stewart, J.; Wagemakers, L.; Williamson, B.; Kan, van J.A.L.

    2002-01-01

    There is evidence that the necrotrophic fungal pathogen Botrytis cinerea is exposed to oxidative processes within plant tissues. The pathogen itself also generates active oxygen species and H2O2 as pathogenicity factors. Our aim was to study how the pathogen may defend itself against cellular damage

  19. The Therapeutic Effects of a Medicinal Plant Mixture in Capsule Form on Catalase Levels in the Semen of Men with Oligospermia

    Directory of Open Access Journals (Sweden)

    Alizadeh Hasti

    2015-01-01

    Full Text Available Objective: In the present study, the therapeutic effects of mixed herbs (onion, ginger, basil, cinnamon, orange peel, yellow and red watermelon seeds, and carrot seed on catalase levels in the semen of men with oligospermia were evaluated. About 50% of recognized infertility factors are male-related factors, and are mainly the result of oligospermia, astenospermia, and teratozoospermia. Materials and Methods: The study participants included 40 males with oligospermia and infertility. The studied medicine were 700 mg capsules containing onion, ginger, basil, cinnamon, orange peel, yellow and red watermelon seeds, and carrot seed (100 mg of each. Catalase activity was measured by Aebi method. Results: A significant increase was observed in catalase level in semen as a result of using the medicinal plant mixture (P < 0.001. Conclusion: Free radicals play an important role in male infertility. Antioxidants can prevent the damaging effects they have on sperm. Oxidative stress reduction can increase the chances of natural fertility or assisted reproductive technology (ART. Medicinal plants have low costs, complications, and easy availability, and cause an increase in semen plasma antioxidants and subsequent improvement in semen parameters. Thus, they can be the source of new hopes for the treatment of infertility.

  20. Fenton reaction-mediated fluorescence quenching of N-acetyl-L-cysteine-protected gold nanoclusters: analytical applications of hydrogen peroxide, glucose, and catalase detection.

    Science.gov (United States)

    Deng, Hao-Hua; Wu, Gang-Wei; He, Dong; Peng, Hua-Ping; Liu, Ai-Lin; Xia, Xing-Hua; Chen, Wei

    2015-11-21

    Given the importance of hydrogen peroxide (H2O2) in many biological processes and its wide application in various industries, the demand for sensitive, accurate, and economical H2O2 sensors is high. In this study, we used Fenton reaction-stimulated fluorescence quenching of N-acetyl-L-cysteine-protected gold nanoclusters (NAC-AuNCs) as a reporter system for the determination of H2O2. After the experimental conditions were optimized, the sensing platform enabled the analysis of H2O2 with a limit of detection (LOD) as low as 0.027 μM. As the glucose oxidase cascade leads to the generation of H2O2 and catalase catalyzes the decomposition of H2O2, these two biocatalytic procedures can be probed by the Fenton reaction-mediated quenching of NAC-AuNCs. The LOD for glucose was found to be 0.18 μM, and the linear range was 0.39-27.22 μM. The LOD for catalase was 0.002 U mL(-1), and the linear range was 0.01-0.3 U mL(-1). Moreover, the proposed sensing methods were successfully applied for human serum glucose detection and the non-invasive determination of catalase activity in human saliva, demonstrating their great potential for practical applications.

  1. Tailoring nutritional and process variables for hyperproduction of catalase from a novel isolated bacterium Geobacillus sp. BSS-7.

    Science.gov (United States)

    Kauldhar, Baljinder Singh; Sooch, Balwinder Singh

    2016-01-14

    Catalase (EC 1.11.1.6) is one of the important industrial enzyme employed in diagnostic and analytical methods in the form of biomarkers and biosensors in addition to their enormous applications in textile, paper, food and pharmaceutical sectors. The present study demonstrates the utility of a newly isolated and adapted strain of genus Geobacillus possessing unique combination of several industrially important extremophilic properties for the hyper production of catalase. The bacterium can grow over a wide range of pH (3-12) and temperature (10-90 °C) with extraordinary capability to produce catalase. A novel extremophilic strain belonging to genus Geobacillus was exploited for the production of catalase by tailoring its nutritional requirements and process variables. One variable at a time traditional approach followed by computational designing was applied to customize the fermentation process. A simple fermentation media containing only three components namely sucrose (0.55 %, w/v), yeast extract (1.0 %, w/v) and BaCl2 (0.08 %, w/v) was designed for the hyperproduction of catalase. A controlled and optimum air supply caused a tremendous increase in the enzyme production on moving the bioprocess from the flask to bioreactor level. The present paper reports high quantum of catalase production (105,000 IU/mg of cells) in a short fermentation time of 12 h. To the best of our knowledge, there is no report in the literature that matches the performance of the developed protocol for the catalase production. This is the first serious study covering intracellular catalase production from thermophilic genus Geobacillus. An increase in intracellular catalase production by 214.72 % was achieved in the optimized medium when transferred from the shake flask to the fermenter level. The extraordinary high production of catalase from Geobacillus sp. BSS-7 makes the isolated strain a prospective candidate for bulk catalase production on an industrial scale.

  2. Mutation of Arabidopsis CATALASE2 results in hyponastic leaves by changes of auxin levels.

    Science.gov (United States)

    Gao, Xiang; Yuan, Hong-Mei; Hu, Ye-Qin; Li, Jing; Lu, Ying-Tang

    2014-01-01

    Auxin and H2 O2 play vital roles in plant development and environmental responses; however, it is unclear whether and how H2 O2 modulates auxin levels. Here, we investigate this question using cat2-1 mutant, which exhibits reduced catalase activity and accumulates high levels of H2 O2 under photorespiratory conditions. At a light intensity of 150 μmol m(-2) s(-1) , the mutant exhibited up-curled leaves that have increased H2 O2 contents and decreased auxin levels. At low light intensities (30 μmol m(-2) s(-1)), the leaves of the mutant were normal, but exhibited reduced H2 O2 contents and elevated auxin levels. These findings suggest that H2 O2 modulates auxin levels. When auxin was directly applied to cat2-1 leaves, the up-curled leaves curled downwards. In addition, transformation of cat2-1 plants with pCAT2:iaaM, which increases auxin levels, rescued the hyponastic leaf phenotype. Using qRT-PCR, we demonstrated that the transcription of auxin synthesis-related genes and of genes that regulate leaf curvature is suppressed in cat2-1. Furthermore, application of glutathione rescued the up-curled leaves of cat2-1 and increased auxin levels, but did not change H2 O2 levels. Thus, the hyponastic leaves of cat2-1 reveal crosstalk between H2 O2 and auxin signalling that is mediated by changes in glutathione redox status. © 2013 John Wiley & Sons Ltd.

  3. Catalase gene disruptant of the human pathogenic yeast Candida albicans is defective in hyphal growth, and a catalase-specific inhibitor can suppress hyphal growth of wild-type cells.

    Science.gov (United States)

    Nakagawa, Yoshiyuki

    2008-01-01

    Although the catalase gene (CAT1) disruptant of the human pathogenic yeast Candida albicans was viable under ordinary growth conditions, we previously found that it could not grow on YPD (yeast extract/peptone/dextrose) containing SDS or at higher growth temperatures. To investigate the pleiotrophic nature of the disruptant, we examined the effect of the catalase inhibitor 3-AT on the growth of wild-type strains. Surprisingly, the addition of 3-AT and SDS caused the wild-type cells to be non-viable on YPD plates. We found an additional phenotype of the catalase gene disruptant: it did not produce normal hyphae on Spider medium. Hyphal growth was observed in a CAP1 (Candida AP-1-like protein gene) disruptant, a HOG1 (high-osmolarity glycerol signaling pathway gene) disruptant, and the double CAP1/HOG1 disruptant, suggesting that the defect in hyphal formation by the catalase disruptant was independent of these genes. Addition of 3-AT and SDS to hyphae-inducing media suppressed growth of normal hyphae in the wild-type strain. The potential necessity for catalase action upon exposure to hyphae-inducing conditions was confirmed by the immediate elevation of the catalase gene message. In spite of the requirement for catalase during hyphal growth, the catalase gene disruptant was capable of forming germ tubes in medium containing serum.

  4. PaCATB, a secreted catalase protecting Podospora anserina against exogenous oxidative stress

    DEFF Research Database (Denmark)

    Zintel, Sandra; Bernhardt, Dominik; Rogowska-Wrzesinska, Adelina

    2011-01-01

    A differential mass spectrometry analysis of secreted proteins from juvenile and senescentPodospora anserina cultures revealed age-related differences in protein profiles. Among other proteins with decreased abundance in the secretome of senescent cultures a catalase, termed PaCATB, was identified...

  5. Time-resolved proton polarisation (TPP) images tyrosyl radical sites in bovine liver catalase.

    Science.gov (United States)

    Zimmer, Oliver; Jouve, Hélène M.; Stuhrmann, Heinrich B.

    2017-05-01

    A differentiation between dynamic polarised protons close to tyrosyl radical sites in catalase and those of the bulk is achieved by time-resolved polarised neutron scattering. Three radical sites, all of them being close to the molecular centre and the heme, appear to be equally possible. Among these is tyr-369 the radial site of which had previously been proven by EPR.

  6. Characterization and stability of D-amino acid oxidase and catalase ...

    African Journals Online (AJOL)

    amino acid oxidase (DAAO) and catalase (CAT) in the permeabilized cells, involved in a summary of our previous works. It was observed that the culture conditions, the permeabilization treatments, the enzyme leakage and pH value of solution ...

  7. Relações da dieta ovo-lácteo-vegetariana com o exercício físico e as enzimas antioxidantes superóxido dismutase e catalase

    Directory of Open Access Journals (Sweden)

    Mírian Rocha Váquez

    2011-06-01

    Full Text Available OBJETIVO: O objetivo deste trabalho foi estudar a influência da dieta ovo-lácteo-vegetariana e do exercício físico extenuante sobre as atividades das enzimas catalase e superóxido dismutase em dez indivíduos masculinos, jovens e saudáveis. MÉTODOS: O controle alimentar aplicou-se por quatro meses. Antes disso, foram recolhidas amostras de sangue em estado basal e cinco minutos após o exercício físico extenuante efetuado em esteira rolante. O mesmo procedimento foi aplicado após o controle alimentar. RESULTADOS: Os resultados mostraram que a dieta ovo-lácteo-vegetariana, em condições de repouso, reduziu de forma significativa a atividade da enzima catalase em 18,98% (pOBJECTIVE: This study aimed to study the influence of an ovolactovegetarian diet and strenuous physical exercise on the activity of the enzymes catalase and superoxide dismutase in 10 young, healthy men whose diet was controlled for four months. METHODS: Blood samples were collected at baseline and after the four-month period, before strenuous exercise and after 5 minutes of strenuous exercise on a treadmill. RESULTS: The results showed that the ovolactovegetarian diet reduced the activity of the enzyme catalase by 18.98% (p<0.05 and increased the activity of the enzyme superoxide dismutase by 77.84% (p<0.001 before strenuous exercise. After strenuous exercise, the ovolactovegetarian diet reduced the activity of the enzyme catalase by 26.11% (p<0.05 and did not affect the activity of the enzyme superoxide dismutase. CONCLUSION: The results indicate that a healthy ovolactovegetarian diet impacts the activity of both enzymes.

  8. Insecticidal potency of RNAi-based catalase knockdown in Rhynchophorus ferrugineus (Oliver) (Coleoptera: Curculionidae).

    Science.gov (United States)

    Al-Ayedh, Hassan; Rizwan-Ul-Haq, Muhammad; Hussain, Abid; Aljabr, Ahmed M

    2016-11-01

    Palm trees around the world are prone to notorious Rhynchophorus ferrugineus, which causes heavy losses of palm plantations. In Middle Eastern countries, this pest is a major threat to date palm orchards. Conventional pest control measures with the major share of synthetic insecticides have resulted in insect resistance and environmental issues. Therefore, in order to explore better alternatives, the RNAi approach was employed to knock down the catalase gene in fifth and tenth larval instars with different dsRNA application methods, and their insecticidal potency was studied. dsRNA of 444 bp was prepared to knock down catalase in R. ferrugineus. Out of the three dsRNA application methods, dsRNA injection into larvae was the most effective, followed by dsRNA application by artificial feeding. Both methods resulted in significant catalase knockdown in various tissues, especially the midgut. As a result, the highest growth inhibition of 123.49 and 103.47% and larval mortality of 80 and 40% were observed in fifth-instar larvae, whereas larval growth inhibition remained at 86.83 and 69.08% with larval mortality at 30 and 10% in tenth-instar larvae after dsRNA injection and artificial diet treatment. The topical application method was the least efficient, with the lowest larval growth inhibition of 57.23 and 45.61% and 0% mortality in fifth- and tenth-instar larvae. Generally, better results were noted at the high dsRNA dose of 5 µL. Catalase enzyme is found in most insect body tissues, and thus its dsRNA can cause broad-scale gene knockdown within the insect body, depending upon the application method. Significant larval mortality and growth inhibition after catalase knockdown in R. ferrugineus confirms its insecticidal potency and suggests a bright future for RNAi-based bioinsecticides in pest control. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  9. Significance of membrane bioreactor design on the biocatalytic performance of glucose oxidase and catalase: Free vs. immobilized enzyme systems

    DEFF Research Database (Denmark)

    Morthensen, Sofie Thage; Meyer, Anne S.; Jørgensen, Henning

    2017-01-01

    Membrane separation of xylose and glucose can be accomplished via oxidation of glucose to gluconic acid by enzymatic glucose oxidase catalysis. Oxygen for this reaction can be supplied via decomposition of hydrogen peroxide by enzymatic catalase catalysis. In order to maximize the biocatalytic...... productivity of glucose oxidase and catalase (gluconic acid yield per total amount of enzyme) the following system set-ups were compared: immobilization of glucose oxidase alone; co-immobilization of glucose oxidase and catalase; glucose oxidase and catalase free in the membrane bioreactor. Fouling......-induced enzyme immobilization in the porous support of an ultrafiltration membrane was used as strategy for entrapment of glucose oxidase and catalase. The biocatalytic productivity of the membrane reactor was found to be highly related to the oxygen availability, which in turn depended on the reactor...

  10. Catalase (KatA) plays a role in protection against anaerobic nitric oxide in Pseudomonas aeruginosa.

    Science.gov (United States)

    Su, Shengchang; Panmanee, Warunya; Wilson, Jeffrey J; Mahtani, Harry K; Li, Qian; Vanderwielen, Bradley D; Makris, Thomas M; Rogers, Melanie; McDaniel, Cameron; Lipscomb, John D; Irvin, Randall T; Schurr, Michael J; Lancaster, Jack R; Kovall, Rhett A; Hassett, Daniel J

    2014-01-01

    Pseudomonas aeruginosa (PA) is a common bacterial pathogen, responsible for a high incidence of nosocomial and respiratory infections. KatA is the major catalase of PA that detoxifies hydrogen peroxide (H2O2), a reactive oxygen intermediate generated during aerobic respiration. Paradoxically, PA displays elevated KatA activity under anaerobic growth conditions where the substrate of KatA, H2O2, is not produced. The aim of the present study is to elucidate the mechanism underlying this phenomenon and define the role of KatA in PA during anaerobiosis using genetic, biochemical and biophysical approaches. We demonstrated that anaerobic wild-type PAO1 cells yielded higher levels of katA transcription and expression than aerobic cells, whereas a nitrite reductase mutant ΔnirS produced ∼50% the KatA activity of PAO1, suggesting that a basal NO level was required for the increased KatA activity. We also found that transcription of the katA gene was controlled, in part, by the master anaerobic regulator, ANR. A ΔkatA mutant and a mucoid mucA22 ΔkatA bacteria demonstrated increased sensitivity to acidified nitrite (an NO generator) in anaerobic planktonic and biofilm cultures. EPR spectra of anaerobic bacteria showed that levels of dinitrosyl iron complexes (DNIC), indicators of NO stress, were increased significantly in the ΔkatA mutant, and dramatically in a ΔnorCB mutant compared to basal levels of DNIC in PAO1 and ΔnirS mutant. Expression of KatA dramatically reduced the DNIC levels in ΔnorCB mutant. We further revealed direct NO-KatA interactions in vitro using EPR, optical spectroscopy and X-ray crystallography. KatA has a 5-coordinate high spin ferric heme that binds NO without prior reduction of the heme iron (Kd ∼6 μM). Collectively, we conclude that KatA is expressed to protect PA against NO generated during anaerobic respiration. We proposed that such protective effects of KatA may involve buffering of free NO when potentially toxic concentrations of

  11. Catalase (KatA plays a role in protection against anaerobic nitric oxide in Pseudomonas aeruginosa.

    Directory of Open Access Journals (Sweden)

    Shengchang Su

    Full Text Available Pseudomonas aeruginosa (PA is a common bacterial pathogen, responsible for a high incidence of nosocomial and respiratory infections. KatA is the major catalase of PA that detoxifies hydrogen peroxide (H2O2, a reactive oxygen intermediate generated during aerobic respiration. Paradoxically, PA displays elevated KatA activity under anaerobic growth conditions where the substrate of KatA, H2O2, is not produced. The aim of the present study is to elucidate the mechanism underlying this phenomenon and define the role of KatA in PA during anaerobiosis using genetic, biochemical and biophysical approaches. We demonstrated that anaerobic wild-type PAO1 cells yielded higher levels of katA transcription and expression than aerobic cells, whereas a nitrite reductase mutant ΔnirS produced ∼50% the KatA activity of PAO1, suggesting that a basal NO level was required for the increased KatA activity. We also found that transcription of the katA gene was controlled, in part, by the master anaerobic regulator, ANR. A ΔkatA mutant and a mucoid mucA22 ΔkatA bacteria demonstrated increased sensitivity to acidified nitrite (an NO generator in anaerobic planktonic and biofilm cultures. EPR spectra of anaerobic bacteria showed that levels of dinitrosyl iron complexes (DNIC, indicators of NO stress, were increased significantly in the ΔkatA mutant, and dramatically in a ΔnorCB mutant compared to basal levels of DNIC in PAO1 and ΔnirS mutant. Expression of KatA dramatically reduced the DNIC levels in ΔnorCB mutant. We further revealed direct NO-KatA interactions in vitro using EPR, optical spectroscopy and X-ray crystallography. KatA has a 5-coordinate high spin ferric heme that binds NO without prior reduction of the heme iron (Kd ∼6 μM. Collectively, we conclude that KatA is expressed to protect PA against NO generated during anaerobic respiration. We proposed that such protective effects of KatA may involve buffering of free NO when potentially toxic

  12. Catalase (KatA) Plays a Role in Protection against Anaerobic Nitric Oxide in Pseudomonas aeruginosa

    Science.gov (United States)

    Su, Shengchang; Panmanee, Warunya; Wilson, Jeffrey J.; Mahtani, Harry K.; Li, Qian; VanderWielen, Bradley D.; Makris, Thomas M.; Rogers, Melanie; McDaniel, Cameron; Lipscomb, John D.; Irvin, Randall T.; Schurr, Michael J.; Lancaster, Jack R.; Kovall, Rhett A.; Hassett, Daniel J.

    2014-01-01

    Pseudomonas aeruginosa (PA) is a common bacterial pathogen, responsible for a high incidence of nosocomial and respiratory infections. KatA is the major catalase of PA that detoxifies hydrogen peroxide (H2O2), a reactive oxygen intermediate generated during aerobic respiration. Paradoxically, PA displays elevated KatA activity under anaerobic growth conditions where the substrate of KatA, H2O2, is not produced. The aim of the present study is to elucidate the mechanism underlying this phenomenon and define the role of KatA in PA during anaerobiosis using genetic, biochemical and biophysical approaches. We demonstrated that anaerobic wild-type PAO1 cells yielded higher levels of katA transcription and expression than aerobic cells, whereas a nitrite reductase mutant ΔnirS produced ∼50% the KatA activity of PAO1, suggesting that a basal NO level was required for the increased KatA activity. We also found that transcription of the katA gene was controlled, in part, by the master anaerobic regulator, ANR. A ΔkatA mutant and a mucoid mucA22 ΔkatA bacteria demonstrated increased sensitivity to acidified nitrite (an NO generator) in anaerobic planktonic and biofilm cultures. EPR spectra of anaerobic bacteria showed that levels of dinitrosyl iron complexes (DNIC), indicators of NO stress, were increased significantly in the ΔkatA mutant, and dramatically in a ΔnorCB mutant compared to basal levels of DNIC in PAO1 and ΔnirS mutant. Expression of KatA dramatically reduced the DNIC levels in ΔnorCB mutant. We further revealed direct NO-KatA interactions in vitro using EPR, optical spectroscopy and X-ray crystallography. KatA has a 5-coordinate high spin ferric heme that binds NO without prior reduction of the heme iron (Kd ∼6 μM). Collectively, we conclude that KatA is expressed to protect PA against NO generated during anaerobic respiration. We proposed that such protective effects of KatA may involve buffering of free NO when potentially toxic concentrations of

  13. Overexpressed Superoxide Dismutase and Catalase Act Synergistically to Protect the Repair of PSII during Photoinhibition in Synechococcus elongatus PCC 7942.

    Science.gov (United States)

    Sae-Tang, Penporn; Hihara, Yukako; Yumoto, Isao; Orikasa, Yoshitake; Okuyama, Hidetoshi; Nishiyama, Yoshitaka

    2016-09-01

    The repair of PSII under strong light is particularly sensitive to reactive oxygen species (ROS), such as the superoxide radical and hydrogen peroxide, and these ROS are efficiently scavenged by superoxide dismutase (SOD) and catalase. In the present study, we generated transformants of the cyanobacterium Synechococcus elongatus PCC 7942 that overexpressed an iron superoxide dismutase (Fe-SOD) from Synechocystis sp. PCC 6803; a highly active catalase (VktA) from Vibrio rumoiensis; and both enzymes together. Then we examined the sensitivity of PSII to photoinhibition in the three strains. In cells that overexpressed either Fe-SOD or VktA, PSII was more tolerant to strong light than it was in wild-type cells. Moreover, in cells that overexpressed both Fe-SOD and VktA, PSII was even more tolerant to strong light. However, the rate of photodamage to PSII, as monitored in the presence of chloramphenicol, was similar in all three transformant strains and in wild-type cells, suggesting that the overexpression of these ROS-scavenging enzymes might not protect PSII from photodamage but might protect the repair of PSII. Under strong light, intracellular levels of ROS fell significantly, and the synthesis de novo of proteins that are required for the repair of PSII, such as the D1 protein, was enhanced. Our observations suggest that overexpressed Fe-SOD and VktA might act synergistically to alleviate the photoinhibition of PSII by reducing intracellular levels of ROS, with resultant protection of the repair of PSII from oxidative inhibition. © The Author 2016. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  14. Enzyme activity in bioregulator-treated tomato ( Solanum ...

    African Journals Online (AJOL)

    activities of lipoxygenase (LOX), catalase, peroxidase, alcohol dehydrogenase and acid phosphatase determined. All treated genotypes showed high LOX activity with a range of 0.06 - 1.07 mmol.abs.units (A234). The NAA-treated NHLy13 genotype had complete loss of catalase activity after 210 s. Peroxidase activity was ...

  15. Enhancement of superoxide dismutase and catalase activity in juvenile brown shrimp, Farfantepenaeus californiensis (Holmes, 1900, fed β-1.3 glucan vitamin E, and β-carotene and infected with white spot syndrome virus Incremento de la actividad superóxido dismutasa y catalasa en juveniles de camarón café Farfantepenaeus californiensis (Holmes, 1900 alimentados con β-1,3 glucano vitamina E y β-caroteno e infectados con el virus de la mancha blanca

    Directory of Open Access Journals (Sweden)

    Rosario Pacheco

    2011-11-01

    Full Text Available The effect of dietary β-Ο-glucan, vitamin E, and β-carotene supplements in juvenile brown shrimp, Farfantepenaeus californiensis, inoculated with white spot syndrome virus (WSSV was evaluated. Groups of 30 organisms (weighing 1 ± 0.5 g were cultured in 60 L fiberglass tanks and fed daily with β-1.3-glucan (0.1%, vitamin E (0.01%, and β-carotene (0.01% for 23 days; the specimens were then inoculated with WSSV. The antioxidant activity of the enzymes superoxide dismutase (SOD and catalase (CAT were determined in the hepatopancreas and muscle at 0, 1, 6, 12, 24, and 48 h after inoculation. Shrimp fed with β-1.3-glucan, vitamin E, and β-carotene significantly increased SOD activity in the hepatopancreas and muscle at 12 and 24 h post-infection, respectively. Shrimp fed with vitamin E and β-1.3-glucan registered an increment in SOD activity from 12 to 48 h post-infection. Shrimp fed with β-carotene increased SOD activity before infection with WSSV, and shrimp fed with β-1.3-glucan and vitamin E increased CAT activity, also before infection. The CAT activity response in shrimp muscle increased with respect to the control group for all treatments tested from 1 to 6 h after inoculation with WSSV. The highest antioxidant response was registered in shrimp fed with vitamin E. Juvenile shrimp fed with vitamin E and later inoculated with WSSV registered 100% mortality at 72 h, but shrimp fed with β-Ο-glucan and β-carotene showed greater resistance to WSSV, with mortality at 144 h post-infection. This study demonstrated the capacity of juvenile Farfantepenaeus californiensis fed β-Ο-glucan, vitamin E, or β-carotene to increase the antioxidant response before and after viral infection.Se evaluó el efecto de β-1,3-glucano, vitamina E y β-caroteno en la dieta de juveniles de camarón café Farfantepenaeus californiensis inoculados con virus del síndrome de la mancha blanca (WSSV. Se colocaron grupos de 30 camarones (peso 1 ± 0,5 g en

  16. Comparative evaluation of the efficacy of ginger and orlistat on obesity management, pancreatic lipase and liver peroxisomal catalase enzyme in male albino rats.

    Science.gov (United States)

    Mahmoud, R H; Elnour, W A

    2013-01-01

    Obesity is a disease involving body weight gain. Several synthetic drugs of better efficacy are being introduced in the modern system of medicine. Orlistat is a pharmacological agent promoting weight loss in obese subjects via inhibiting of gastric and pancreatic lipase. Ginger (Zingiber officinale Roscoe, Zingiberacae) is one of the most commonly used spices around the world; it has long been used in traditional medicine as a cure for some diseases. To evaluate the effect of ginger and orlistat on rats fed high fat diet. Forty male Albino rats were either not treated (control), or fed high fat diet, or fed high fat diet with dietary orlistat supplementation (200 mg/kg diet), or fed high fat diet supplemented with 5% ginger powder. After four weeks of treatment, final body weight and food intake were determined. Blood samples were collected, lipid parameters, total bilirubin, pancreatic lipase were determined. Liver peroxisomes were isolated from rat livers and peroxisomal catalase activity was determined. Treatment with both ginger and orlistat had significant effect in reducing body weight, besides, supplementing diet with orlistat increase food intake. Both ginger and orlistat had the ability to reduce lipid profile, ginger had great effect in increasing HDL-cholesterol than orlistat. When compared to the control group, ginger treatment did not alter either total bilirubin or pancreatic lipase activity while orlistat clearly reduced their concentration. Orlistat supplementation induced a significant reduction in peroxisomal catalase level, while ginger has been reported to interfere with enzyme activity increasing its level. Ginger has a great ability to reduce body weight without inhibiting pancreatic lipase level, or affecting bilirubin concentration, with positive effect on increasing peroxisomal catalase level and HDL-cholesterol.

  17. Understanding the role of the catalase/peroxide genes in H2O2 resistance of E. coli serotype O157:H7 biofilms

    Science.gov (United States)

    Introduction: Escherichia coli serotype O157:H7 defenses against H2O2 include the peroxiredoxin AhpC and three catalases: KatG (catalase-peroxidase), KatE (catalase), and the plasmid-encoded KatP (catalase/peroxidase). AhpC, KatG, and KatP are induced by OxyR in exponential phase, while KatE is indu...

  18. Multifrequency EPR Studies of Manganese Catalases Provide a Complete Description of Proteinaceous Nitrogen Coordination

    OpenAIRE

    Stich, Troy A.; Whittaker, James W.; Britt, R. David

    2010-01-01

    Pulse electron paramagnetic resonance (EPR) spectroscopy is employed at two very different excitation frequencies, 9.77 and 30.67 GHz, in the study of the nitrogen coordination environment of the Mn(III)Mn(IV) state of the dimanganese-containing catalases from Lactobacillus plantarum and Thermus thermophilus. Consistent with previous studies, the lower-frequency results reveal one unique histidine nitrogen-Mn cluster interaction. For the first time, a second, more strongly hyperfine-coupled 1...

  19. High-catalase strains of Mycobacterium kansasii isolated from water in Texas.

    OpenAIRE

    Steadham, J E

    1980-01-01

    Isolation techniques with membrane-filtered potable water samples resulted in the isolation of potentially pathogenic high-catalase strains of Mycobacterium kansasii from 8 of 19 representative outlets in a small central Texas town. Mycobacterium gordonae was isolated from all samples, and Mycobacterium fortuitum was isolated from two samples. Data on chlorine levels are presented along with a possible explanation for the unusually high numbers of mycobacteria in these potable water samples. ...

  20. Prevalence of Catalase (-21 A/T Gene Variant in South Indian (Tamil Population

    Directory of Open Access Journals (Sweden)

    A. Lourdhu Mary

    2014-01-01

    Full Text Available Catalase, an endogenous antioxidant enzyme, is responsible for regulating reactive species levels. Several epidemiologic studies have suggested that single nucleotide polymorphism in catalase gene may be associated with many diseases. The genotype of CAT (-21 A/T point mutation in promoter region of catalase gene was determined by polymerase chain based restriction fragment length polymorphism analysis in the DNA of 100 healthy volunteers. The frequency of CAT (-21 A/T gene polymorphism AA, AT, and TT genotypes was found to be 7, 23, and 70 percent, respectively. The mutant “T” allele frequency was found to be 0.82 among the south Indian (Tamil population. Chi square analysis showed that the study population lies within the Hardy-Weinberg equilibrium. The wild type genotype (AA was found to be very low (7% and the mutant genotype (AT/TT was found to be more prevalent (93% among the south Indian population. This suggests that the high prevalence of mutant genotype may increase the susceptibility to oxidative stress associated diseases.

  1. α-Syntrophin stabilizes catalase to reduce endogenous reactive oxygen species levels during myoblast differentiation.

    Science.gov (United States)

    Moon, Jae Yun; Choi, Su Jin; Heo, Cheol Ho; Kim, Hwan Myung; Kim, Hye Sun

    2017-07-01

    α-Syntrophin is a component of the dystrophin-glycoprotein complex that interacts with various intracellular signaling proteins in muscle cells. The α-syntrophin knock-down C2 cell line (SNKD), established by infecting lentivirus particles with α-syntrophin shRNA, is characterized by a defect in terminal differentiation and increase in cell death. Since myoblast differentiation is accompanied by intensive mitochondrial biogenesis, the generation of intracellular reactive oxygen species (ROS) is also increased during myogenesis. Two-photon microscopy imaging showed that excessive intracellular ROS accumulated during the differentiation of SNKD cells as compared with control cells. The formation of 4-hydroxynonenal adduct, a byproduct of lipid peroxidation during oxidative stress, significantly increased in differentiated SNKD myotubes and was dramatically reduced by epigallocatechin-3-gallate, a well-known ROS scavenger. Among antioxidant enzymes, catalase was significantly decreased during differentiation of SNKD cells without changes at the mRNA level. Of interest was the finding that the degradation of catalase was rescued by MG132, a proteasome inhibitor, in the SNKD cells. This study demonstrates a novel function of α-syntrophin. This protein plays an important role in the regulation of oxidative stress from endogenously generated ROS during myoblast differentiation by modulating the protein stability of catalase. © 2017 Federation of European Biochemical Societies.

  2. Role of. pi. -cation radicals in the enzymatic cycles of peroxidases, catalases, and nitrite and sulfite reductases

    Energy Technology Data Exchange (ETDEWEB)

    Hanson, L K; Chang, C K; Davis, M S; Fajer, J

    1980-01-01

    Charge iterative extended Hueckel calculations, and magnetic and optical results on porphyrins, chlorins, and isobacteriochlorins (1) suggest that the catalytic cycles of the enzymes horseradish peroxidase, catalase, Neurospora crassa catalase, and nitrite and sulfite reductases proceed via ..pi..-cation radicals of their prosthetic groups; (2) offer distinguishing features for the optical and magnetic spectra of these radicals, pertinent to their detection as enzymatic intermediates; (3) reconcile the seemingly contradictory optical and NMR data on Compounds I of horseradish peroxidase; and (4) predict that the axial ligation of the heme differs for horseradish peroxidase and catalase.

  3. Benzothiazole Aniline Tetra(ethylene glycol) and 3-Amino-1,2,4-triazole Inhibit Neuroprotection against Amyloid Peptides by Catalase Overexpression in Vitro

    Science.gov (United States)

    2013-01-01

    Alzheimer’s disease, Familial British dementia, Familial Danish dementia, Type 2 diabetes mellitus, plus Creutzfeldt-Jakob disease are associated with amyloid fibril deposition and oxidative stress. The antioxidant enzyme catalase is a neuroprotective amyloid binding protein. Herein the effects of catalase overexpression in SH-SY5Y neuronal cells on the toxicity of amyloid-β (Aβ), amyloid-Bri (ABri), amyloid-Dan (ADan), amylin (IAPP), and prion protein (PrP) peptides were determined. Results showed catalase overexpression was neuroprotective against Aβ, ABri, ADan, IAPP, and PrP peptides. The catalase inhibitor 3-amino-1,2,4-triazole (3-AT) and catalase-amyloid interaction inhibitor benzothiazole aniline tetra(ethylene glycol) (BTA-EG4) significantly enhanced neurotoxicity of amyloid peptides in catalase overexpressing neuronal cells. This suggests catalase neuroprotection involves breakdown of hydrogen peroxide (H2O2) plus a direct binding interaction between catalase and the Aβ, ABri, ADan, IAPP, and PrP peptides. Kisspeptin 45–50 had additive neuroprotective actions against the Aβ peptide in catalase overexpressing cells. The effects of 3-AT had an intracellular site of action, while catalase-amyloid interactions had an extracellular component. These results suggest that the 3-AT and BTA-EG4 compounds may be able to inhibit endogenous catalase mediated neuroprotection. Use of BTA-EG4, or compounds that inhibit catalase binding to amyloid peptides, as potential therapeutics for Neurodegenerative diseases may therefore result in unwanted effects. PMID:23968537

  4. OxyR-regulated catalase CatB promotes the virulence in rice via detoxifying hydrogen peroxide in Xanthomonas oryzae pv. oryzae.

    Science.gov (United States)

    Yu, Chao; Wang, Nu; Wu, Maosen; Tian, Fang; Chen, Huamin; Yang, Fenghuan; Yuan, Xiaochen; Yang, Ching-Hong; He, Chenyang

    2016-11-08

    To facilitate infection, Xanthomonas oryzae pv. oryzae (Xoo), the bacterial blight pathogen of rice, needs to degrade hydrogen peroxide (H2O2) generated by the host defense response via a mechanism that is mediated by the transcriptional regulator OxyR. The catalase (CAT) gene catB has previously been shown to belong to the OxyR regulon in Xoo. However, its expression patterns and function in H2O2 detoxification and bacterial pathogenicity on rice remain to be elucidated. The catB gene encodes a putative catalase and is highly conserved in the sequenced strains of Xanthomonas spp. β-galactosidase analysis and electrophoretic mobility shift assays (EMSA) showed that OxyR positively regulated the transcription of catB by directly binding to its promoter region. The quantitative real-time PCR (qRT-PCR) assays revealed that the expression levels of catB and oxyR were significantly induced by H2O2. Deletion of catB or oxyR drastically impaired bacterial viability in the presence of extracellular H2O2 and reduced CAT activity, demonstrating that CatB and OxyR contribute to H2O2 detoxification in Xoo. In addition, ΔcatB and ΔoxyR displayed shorter bacterial blight lesions and reduced bacterial growth in rice compared to the wild-type stain, indicating that CatB and OxyR play essential roles in the virulence of Xoo. Transcription of catB is enhanced by OxyR in response to exogenous H2O2. CatB functions as an active catalase that is required for the full virulence of Xoo in rice.

  5. Ethanol-induced liver injury and changes in sulfur amino acid metabolomics in glutathione peroxidase and catalase double knockout mice.

    Science.gov (United States)

    Kim, Sun J; Lee, Joo W; Jung, Young S; Kwon, Do Y; Park, Hee K; Ryu, Chang S; Kim, Sang K; Oh, Goo T; Kim, Young C

    2009-06-01

    Oxidative stress via generation of reactive oxygen species is suggested to be the major mechanism of alcohol-induced liver injury. We investigated the effects of glutathione peroxidase-1 and catalase double deficiency (Gpx-1(-/-)/Cat(-/-)) on liver injury and changes in the sulfur amino acid metabolism induced by binge ethanol administration. Ethanol (5 g/kg) was administered orally to the wild-type and the Gpx-1(-/-)/Cat(-/-) mice every 12 h for a total of three doses. Mice were sacrificed 6 h after the final dose. The Gpx-1/Cat deficiency alone increased malondialdehyde levels in liver significantly. Hepatic methionine adenosyltransferase (MAT) activity and S-adenosylmethionine levels were decreased, however, glutathione contents were not changed. Ethanol administration to the Gpx-1(-/-)/Cat(-/-) mice increased the elevation of serum alanine aminotransferase activity, plasma homocysteine levels, hepatic fat accumulation and lipid peroxidation compared with the wild-type animals challenged with ethanol. Also the reduction of MAT activity and S-adenosylmethionine levels was enhanced, but MATI/III expression was increased significantly. The results indicate that Gpx-1 and Cat have critical roles in the protection of liver against binge ethanol exposure. Augmentation of ethanol-induced oxidative stress may be responsible for the impairment of the transsulfuration reactions and the aggravation of acute liver injury in the Gpx-1(-/-)/Cat(-/-) mice.

  6. In Vitro Effect of Sodium Fluoride on Malondialdehyde Concentration and on Superoxide Dismutase, Catalase, and Glutathione Peroxidase in Human Erythrocytes

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    José Gutiérrez-Salinas

    2013-01-01

    Full Text Available The aim of this paper was to describe the in vitro effect of sodium fluoride (NaF on the specific activity of the major erythrocyte antioxidant enzymes, as well as on the membrane malondialdehyde concentration, as indicators of oxidative stress. For this purpose, human erythrocytes were incubated with NaF (0, 7, 28, 56, and 100 μg/mL or NaF (100 μg/mL + vitamin E (1, 2.5, 5 and 10 μg/mL. The malondialdehyde (MDA concentration on the surface of the erythrocytes was determined, as were the enzymatic activities of superoxide dismutase (SOD, catalase (CAT, and glutathione peroxidase (GlPx. Our results demonstrated that erythrocytes incubated with increasing NaF concentrations had an increased MDA concentration, along with decreased activity of antioxidant enzymes. The presence of vitamin E partially reversed the toxic effects of NaF on erythrocytes. These findings suggest that NaF induces oxidative stress in erythrocytes in vitro, and this stress is partially reversed by the presence of vitamin E.

  7. Spatial distribution structure and volume of Colombian black oak forest (Colombobalanus excelsa (Lozano, Hern. Cam. & Henao, J.E. Nixon & Crepet National Natural Park Cueva de los Guácharos

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    David Eduardo Dávila

    2012-12-01

    Full Text Available The spatial distribution of Colombobalanus excelsa forests in the Cueva de los Guácharos Natural National Park and its buffer zone was determined. The forest’s structural parameters were determined by conducting a stratified forest inventory that consisted of four plots of 0.5 ha distributed in two strata. The first stratum was located in the park and the second in its buffer zone. Each strip consisted of plots of 20 x 50 m within which individuals with diameters at breast height = 10 cm DBH were measured for total height, crown diameter and the condition of each tree. Within each strip a 10 x 10 m subplot was used to assess individuals with DBH = 10 cm and heights greater than 3 m. In addition the number of seedlings of height = 0.3 m were counted in subplots of 5 x 5 m. Models were generated to estimate the height and volume as a function of DBH. We report a total of eight natural stands of black oak reaching 2000 ha of which 28.3 ha were found within the park. We report a density of 281.7 trees ha-1 with a basal area of 52.33 m2 ha-1 and a volume of 761.65 m3 ha-1. The form-factor for the species was of 0.76041. Six models were fitted to estimate the height and six for volume adjustments of 0.90 and 0.988, respectively.

  8. Identification of Scedosporium boydii catalase A1 gene, a reactive oxygen species detoxification factor highly expressed in response to oxidative stress and phagocytic cells.

    Science.gov (United States)

    Mina, Sara; Staerck, Cindy; d'Almeida, Sènan M; Marot, Agnès; Delneste, Yves; Calenda, Alphonse; Tabiasco, Julie; Bouchara, Jean-Philippe; Fleury, Maxime J J

    2015-12-01

    Scedosporium boydii is an opportunistic filamentous fungus which may be responsible for a large variety of infections in both immunocompetent and immunocompromised individuals. This fungus belongs to the Scedosporium apiospermum species complex which usually ranks second among the filamentous fungi colonizing the airways of patients with cystic fibrosis (CF). Species of the S. apiospermum complex are able to chronically colonize the CF airways suggesting pathogenic mechanisms allowing persistence and growth of these fungi in the respiratory tract. Few putative virulence factors have been purified and characterized so far in the S. apiospermum complex including a cytosolic Cu,Zn-superoxide dismutase (SOD) and a monofunctional catalase (catalase A1). Upon microbial infection, host phagocytes release reactive oxygen species (ROS), such as hydrogen peroxide, as part of the antimicrobial response. Catalases are known to protect pathogens against ROS by degradation of the hydrogen peroxide. Here, we identified the S. boydii catalase A1 gene (CATA1) and investigated its expression in response to the environmental conditions encountered in the CF airways and to the oxidative stress. Results showed that S. boydii CATA1 gene expression is not affected by hypoxia, hypercapnia or pH changes. In contrast, CATA1 gene was overexpressed in response to a chemically induced oxidative stress with a relative gene expression 37-fold higher in the presence of 250 μM H(2)O(2), 20-fold higher with 250 μM menadione and 5-fold higher with 2 mM paraquat. Moreover, S. boydii CATA1 gene expression progressively increased upon exposure to activated THP-1-derived macrophages, reaching a maximum after 12 h (26 fold). Activated HL60-derived neutrophils and activated human peripheral blood neutrophils more rapidly induced S. boydii CATA1 gene overexpression, a maximum gene expression level being reached at 75 min (17 fold) and 60 min (15 fold), respectively. In contrast expression of the gene

  9. Dendrometria de espécies nativas em plantios homogêneos no estado de Roraima: andiroba (Carapa guianensis Aubl, castanha-do-Brasil (Bertholletia excelsa Bonpl., ipê-roxo (Tabebuia avellanedae Lorentz ex Griseb e jatobá (Hymenaea courbaril L. Dendrometry of native species in homogeneous stands in the Roraima state: andiroba (Carapa guianensis Aubl, castanha-do-brasil (Bertholletia excelsa Bonpl, ipê-roxo (Tabebuia avellanedae Lorentz ex Griseb and jatobá (Hymenaea courbaril L.

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    Helio Tonini

    2005-09-01

    Full Text Available Estudou-se o crescimento e a seleção de equações para quatro espécies florestais nativas visando identificar espécies promissoras para o plantio em programas de reflorestamentos e em sistemas agroflorestais no Estado de Roraima. O crescimento da andiroba (Carapa guianensis Aubl., da castanha-do-brasil (Bertholletia excelsa Bonpl., do ipê-roxo (Tabebuia avellanedae Lorentz ex Griseb. e do jatobá (Hymenaea courbaril L., aos sete anos de idade, mostrou-se promissor atingindo incrementos médios anuais em volume comercial de 6.3; 14.6; 6.0 e 2.3 m³.ha-1.ano-1, respectivamente. Em relação ao crescimento em diâmetro, todas as espécies apresentaram incrementos médios anuais em diâmetro maiores do que 1 cm, sendo superiores aos observados para árvores crescendo em florestas naturais. A análise estatística, indicou a equação hipsométrica de Prodan como a de melhor ajuste para estimar a altura em função do diâmetro para as quatro espécies analisadas. No entanto, a análise gráfica indicou que a forma da curva altura/diâmetro variou com a espécie sendo necessário o ajuste em separado. O ajuste de equações de volume comercial com casca e fator de forma comercial mostraram ser necessário o ajuste de diferentes equações em função da espécie. A análise gráfica das curvas de volume comercial e fator de forma indicaram que as espécies diferiram em ambos os parâmetros, indicando que a utilização de um fator de forma médio para todas as espécies deve ser evitado, como forma de aumentar a precisão nas estimativas volumétricas.The growth and selection of equations for four native forest species was studied aiming to identify promising species for homogeneous stands, and agroflorestry systems in the Roraima state. The growth of andiroba (Carapa guianensis Aubl., castanha-do-brasil (Bertholletia excelsa Bonpl., ipê-roxo (Tabebuia avellanedae Lorentz ex Griseb and jatobá (Hymenaea courbaril L. to the seven years of age

  10. Increasing the endogenous NO level causes catalase inactivation and reactivation of intercellular apoptosis signaling specifically in tumor cells.

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    Bauer, Georg

    2015-12-01

    Tumor cells generate extracellular superoxide anions and are protected against intercellular apoptosis-inducing HOCl- and NO/peroxynitrite signaling through the expression of membrane-associated catalase. This enzyme decomposes H2O2 and thus prevents HOCl synthesis. It efficiently interferes with NO/peroxynitrite signaling through oxidation of NO and decomposition of peroxynitrite. The regulatory potential of catalase at the crosspoint of ROS and RNS chemical biology, as well as its high local concentration on the outside of the cell membrane of tumor cells, establish tight control of intercellular signaling and thus prevent tumor cell apoptosis. Therefore, inhibition of catalase or its inactivation by singlet oxygen reactivate intercellular apoptosis-inducing signaling. Nitric oxide and peroxynitrite are connected with catalase in multiple and meaningful ways, as (i) NO can be oxidated by compound I of catalase, (ii) NO can reversibly inhibit catalase, (iii) peroxynitrite can be decomposed by catalase and (iv) the interaction between peroxynitrite and H2O2 leads to the generation of singlet oxygen that inactivates catalase. Therefore, modulation of the concentration of free NO through addition of arginine, inhibition of arginase, induction of NOS expression or inhibition of NO dioxygenase triggers an autoamplificatory biochemical cascade that is based on initial formation of singlet oxygen, amplification of superoxide anion/H2O2 and NO generation through singlet oxygen dependent stimulation of the FAS receptor and caspase-8. Finally, singlet oxygen is generated at sufficiently high concentration to inactivate protective catalase and to reactivate intercellular apoptosis-inducing ROS signaling. This regulatory network allows to establish several pathways for synergistic interactions, like the combination of modulators of NO metabolism with enhancers of superoxide anion generation, modulators of NO metabolism that act at different targets and between modulators of

  11. KatG, the Bifunctional Catalase of Xanthomonas citri subsp. citri, Responds to Hydrogen Peroxide and Contributes to Epiphytic Survival on Citrus Leaves.

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    María Laura Tondo

    Full Text Available Xanthomonas citri subsp. citri (Xcc is the bacterium responsible for citrus canker. This bacterium is exposed to reactive oxygen species (ROS at different points during its life cycle, including those normally produced by aerobic respiration or upon exposition to ultraviolet (UV radiation. Moreover, ROS are key components of the host immune response. Among enzymatic ROS-detoxifying mechanisms, catalases eliminate H2O2, avoiding the potential damage caused by this specie. Xcc genome includes four catalase genes. In this work, we studied the physiological role of KatG, the only bifunctional catalase of Xcc, through the construction and characterization of a modified strain (XcckatG, carrying an insertional mutation in the katG gene. First, we evaluated the involvement of KatG in the bacterial adaptive response to H2O2. XcckatG cultures exhibited lower catalase activity than those of the wild-type strain, and this activity was not induced upon treatment with sub-lethal doses of H2O2. Moreover, the KatG-deficient mutant exhibited decreased tolerance to H2O2 toxicity compared to wild-type cells and accumulated high intracellular levels of peroxides upon exposure to sub-lethal concentrations of H2O2. To further study the role of KatG in Xcc physiology, we evaluated bacterial survival upon exposure to UV-A or UV-B radiation. In both conditions, XcckatG showed a high mortality in comparison to Xcc wild-type. Finally, we studied the development of bacterial biofilms. While structured biofilms were observed for the Xcc wild-type, the development of these structures was impaired for XcckatG. Based on these results, we demonstrated that KatG is responsible for Xcc adaptive response to H2O2 and a key component of the bacterial response to oxidative stress. Moreover, this enzyme plays an important role during Xcc epiphytic survival, being essential for biofilm formation and UV resistance.

  12. Mitochondrial-Targeted Catalase Protects Against High-Fat Diet-Induced Muscle Insulin Resistance by Decreasing Intramuscular Lipid Accumulation.

    Science.gov (United States)

    Lee, Hui-Young; Lee, Jae Sung; Alves, Tiago; Ladiges, Warren; Rabinovitch, Peter S; Jurczak, Michael J; Choi, Cheol Soo; Shulman, Gerald I; Samuel, Varman T

    2017-08-01

    We explored the role of reactive oxygen species (ROS) in the pathogenesis of muscle insulin resistance. We assessed insulin action in vivo with a hyperinsulinemic-euglycemic clamp in mice expressing a mitochondrial-targeted catalase (MCAT) that were fed regular chow (RC) or a high-fat diet (HFD) or underwent an acute infusion of a lipid emulsion. RC-fed MCAT mice were similar to littermate wild-type (WT) mice. However, HFD-fed MCAT mice were protected from diet-induced insulin resistance. In contrast, an acute lipid infusion caused muscle insulin resistance in both MCAT and WT mice. ROS production was decreased in both HFD-fed and lipid-infused MCAT mice and cannot explain the divergent response in insulin action. MCAT mice had subtly increased energy expenditure and muscle fat oxidation with decreased intramuscular diacylglycerol (DAG) accumulation, protein kinase C-θ (PKCθ) activation, and impaired insulin signaling with HFD. In contrast, the insulin resistance with the acute lipid infusion was associated with increased muscle DAG content in both WT and MCAT mice. These studies suggest that altering muscle mitochondrial ROS production does not directly alter the development of lipid-induced insulin resistance. However, the altered energy balance in HFD-fed MCAT mice protected them from DAG accumulation, PKCθ activation, and impaired muscle insulin signaling. © 2017 by the American Diabetes Association.

  13. MicroRNA-30b-Mediated Regulation of Catalase Expression in Human ARPE-19 Cells

    Science.gov (United States)

    Haque, Rashidul; Chun, Eugene; Howell, Jennifer C.; Sengupta, Trisha; Chen, Dan; Kim, Hana

    2012-01-01

    Background Oxidative injury to retinal pigment epithelium (RPE) and retinal photoreceptors has been linked to a number of retinal diseases, including age-related macular degeneration (AMD). Reactive oxygen species (ROS)-mediated gene expression has been extensively studied at transcriptional levels. Also, the post-transcriptional control of gene expression at the level of translational regulation has been recently reported. However, the microRNA (miRNA/miR)-mediated post-transcriptional regulation in human RPE cells has not been thoroughly looked at. Increasing evidence points to a potential role of miRNAs in diverse physiological processes. Methodology/Principal Findings We demonstrated for the first time in a human retinal pigment epithelial cell line (ARPE-19) that the post-transcriptional control of gene expression via miRNA modulation regulates human catalase, an important and potent component of cell's antioxidant defensive network, which detoxifies hydrogen peroxide (H2O2) radicals. Exposure to several stress-inducing agents including H2O2 has been reported to alter miRNA expression profile. Here, we demonstrated that a sublethal dose of H2O2 (200 µM) up-regulated the expression of miR-30b, a member of the miR-30 family, which inhibited the expression of endogenous catalase both at the transcript and protein levels. However, antisense (antagomirs) of miR-30b was not only found to suppress the miR-30b mimics-mediated inhibitions, but also to dramatically increase the expression of catalase even under an oxidant environment. Conclusions/Significance We propose that a microRNA antisense approach could enhance cytoprotective mechanisms against oxidative stress by increasing the antioxidant defense system. PMID:22880027

  14. A Simple and Accurate Method for Measuring Enzyme Activity.

    Science.gov (United States)

    Yip, Din-Yan

    1997-01-01

    Presents methods commonly used for investigating enzyme activity using catalase and presents a new method for measuring catalase activity that is more reliable and accurate. Provides results that are readily reproduced and quantified. Can also be used for investigations of enzyme properties such as the effects of temperature, pH, inhibitors,…

  15. Identification and characteristic analysis of the catalase gene from Locusta migratoria.

    Science.gov (United States)

    Zhang, Xueyao; Li, Yahong; Wang, Junxiu; Zhang, Tingting; Li, Tao; Dong, Wei; Ma, Enbo; Zhang, Jianzhen

    2016-09-01

    Catalase (CAT) is a ubiquitous antioxidant enzyme in almost all living organisms exposed to atmosphere, which involved in decomposing harmful hydrogen peroxide, into oxygen and water. In this study, a full-length cDNA (1524bp) encoding the catalase gene (LmCAT) from Locusta migratoria was cloned (accession number KT716445). The open reading frame of the LmCAT gene encoded 507 amino acids and shared 57.8%-97.8% amino acid identities with other insect CATs. The coding region was interrupted by 9 introns, while its promoter region contained 15 putative binding sites for 5 kinds of transcriptional regulation factors. For the stage-specific expression profile, LmCAT was highly expressed in the fourth-instar nymphs. For the tissue-specific expression profile, the LmCAT transcripts were highest in the fat bodies, and relatively abundant in the gastric caecum, Malpighian tubules, ovary and integument. Moreover, the result showed that quercetin could significantly induce the expression level of LmCAT. The expression of LmCAT could be silenced by RNAi, but the moralities were not significantly different between control and RNAi groups. Our results would provide valuable information for further study on the ROS regulation mechanism in insect. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. ATTEMPT IN CLASSIFICATION OF CATALASE-POSITIVE STAPHYLOCOCCI AND MICROCOCCI1

    Science.gov (United States)

    Mossel, D. A. A.

    1962-01-01

    Mossel, D. A. A. (Central Institute for Nutrition and Food Research T.N.O., Utrecht, The Nethrlands). Attempt in classification of catalase-positive staphylococci and micrococci. J. Bacteriol. 84:1140–1147. 1962.—About 390 strains of Staphylococcus aureus, isolated from clinical material, and about 190 strains of coagulase-negative staphylococci and micrococci from strictly nonclinical habitats were studied by the following recently recommended biochemical tests: anaerobic dissimilation (“fermentation”) of mannitol, gelatin liquefaction, type of growth on tellurite-glycine agar, hydrolysis of urea, and KCN tolerance. The latter three tests appeared either not specific for, or not positive for, most S. aureus strains. Virtually all strains of S. aureus were gelatin-positive, but 71% of the other types of cocci also liquefied gelatin. Rapid anaerobic breakdown of mannitol, however, was shown by ca. 95% of the strains of S. aureus, and late fermentation by an additional 3%. Of 105 obligately aerobic coagulase tive cocci (micrococci), none fermented mannitol; of 40 facultatively anaerobic, coagulase-negative cocci (staphylococci), only 7 (18%) fermented mannitol. Oxidative metabolism of mannitol occurred in only three (mannitol salt agar while 13% of the S. aureus strains tested were white. A key to the classification of catalase-positive cocci consistent with that currently used for Enterobacteriaceae has been based on these figures. PMID:13936221

  17. High level extracellular production of a recombinant alkaline catalase in E. coli BL21 under ethanol stress and its application in hydrogen peroxide removal after cotton fabrics bleaching.

    Science.gov (United States)

    Yu, Zhenxiao; Zheng, Hongchen; Zhao, Xingya; Li, Shufang; Xu, Jianyong; Song, Hui

    2016-08-01

    The effects of induction parameters, osmolytes and ethanol stress on the productivity of the recombinant alkaline catalase (KatA) in Escherichia coli BL21 (pET26b-KatA) were investigated. The yield of soluble KatA was significantly enhanced by 2% ethanol stress. And a certain amount of Triton X-100 supplementation could markedly improved extracellular ratio of KatA. A total soluble catalase activity of 78,762U/mL with the extracellular ratio of 92.5% was achieved by fed-batch fermentation in a 10L fermentor, which was the highest yield so far. The purified KatA showed high stability at 50°C and pH 6-10. Application of KatA for elimination of H2O2 after cotton fabrics bleaching led to less consumption of water, steam and electric power by 25%, 12% and 16.7% respectively without productivity and quality losing of cotton fabrics. Thus, the recombinant KatA is a promising candidate for industrial production and applications. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Scavenging of free radicals in gas-phase mainstream cigarette smoke by immobilized catalase at filter level.

    Science.gov (United States)

    Lu, Xin; Hua, Zhaozhe; Du, Guocheng; Ma, Xiaolong; Cao, Jianhua; Yang, Zhanping; Chen, Jian

    2008-03-01

    Catalase is well known as capable of inducing the decomposition of H(2)O(2). In this study, a kind of immobilized catalase (entrapped in cross-linked chitosan beads) was dispersed in conventional acetate filter as an antioxidant additive. Quantitative estimation of the free radicals in mainstream cigarette smoke (MCS) was performed to address the effect of this modified filter. It was found that the levels of PBN adduct and NO(*)/NO(2)(*) associated with the gas-phase mainstream cigarette smoke (GPCS) were efficiently decreased by approximately 40% through catalase filtering. Besides, the modified filter was found to lower the MCS-induced adverse biological effects including lipid peroxidation and mutagenicity. This was proved to be substantially attributed to the catalase-dependent breakdown of NO(*), which was stimulated by some of peroxides (most probably being H(2)O(2)), the dismutation products of tar particulate matters (TPM). These results highlighted a promising approach to reduce the smoking-associated health risks to passive smokers. Moreover, the mechanisms of catalase filtering may be helpful for the development of appropriate immobilized enzyme systems to be applied for reducing health risks associated with gaseous pollutants.

  19. A factor converting viable but nonculturable Vibrio cholerae to a culturable state in eukaryotic cells is a human catalase.

    Science.gov (United States)

    Senoh, Mitsutoshi; Hamabata, Takashi; Takeda, Yoshifumi

    2015-08-01

    In our previous work, we demonstrated that viable but nonculturable (VBNC) Vibrio cholerae O1 and O139 were converted to culturable by coculture with eukaryotic cells. Furthermore, we isolated a factor converting VBNC V. cholerae to culturable (FCVC) from a eukaryotic cell line, HT-29. In this study, we purified FCVC by successive column chromatographies comprising UNO Q-6 anion exchange, Bio-Scale CHT2-1 hydroxyapatite, and Superdex 200 10/300 GL. Homogeneity of the purified FCVC was demonstrated by SDS-PAGE. Nano-LC MS/MS analysis showed that the purified FCVC was a human catalase. An experiment of RNAi knockdown of catalase mRNA from HT-29 cells and treatment of the purified FCVC with a catalase inhibitor, 3-amino-1,2,4-triazole confirmed that the FCVC was a catalase. A possible role of the catalase in converting a VBNC V. cholerae to a culturable state in the human intestine is discussed. © 2015 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

  20. Frequency of polymorphism -262 c/t in catalase gene and oxidative damage in Slovak children with bronchial asthma.

    Science.gov (United States)

    Babusikova, Eva; Jesenak, Milos; Evinova, Andrea; Banovcin, Peter; Dobrota, Dusan

    2013-12-01

    Bronchial asthma is a complex disease in which genetic factors, environmental factors and oxidative damage are responsible for the initiation and modulation of disease progression. If antioxidant mechanisms fail, reactive oxygen species damage the biomolecules followed by progression of the disease. Catalase is one of the most important endogenous enzymatic antioxidants. In the present study, we examined the hypothesis that increased oxidative damage and polymorphism in the CAT gene (-262 promoter region, C/T) are associated with childhood bronchial asthma. Genotyping of the polymorphisms in the CAT gene in healthy (249) and asthmatic children (248) was performed using polymerase chain reaction-restriction fragment length polymorphism. Markers of oxidative damage: content of sulfhydryl groups and thiobarbituric acid-reactive substances were determined by spectrophotometry in children. The TT genotype of catalase was more frequent among the asthmatic patients (22.6%) than in healthy children (4.8%) (odds ratio=5.63; 95% confidence interval=2.93-10.81, Pbronchial asthma and in catalase TT genotype compared to other catalase genotypes of this gene. These results suggest that catalase polymorphism might participate in development of bronchial asthma and in enhanced oxidative damage in asthmatic children. Genetic variation of enzymatic antioxidants may modulate disease risk. Copyright © 2013 SEPAR. Published by Elsevier Espana. All rights reserved.

  1. Polyhemoglobin-superoxide dismutase-catalase-carbonic anhydrase: a novel biotechnology-based blood substitute that transports both oxygen and carbon dioxide and also acts as an antioxidant.

    Science.gov (United States)

    Bian, Yuzhu; Rong, Zhixia; Chang, Thomas Ming Swi

    2012-02-01

    Polyhemoglobin-superoxide dismutase-catalase-carbonic anhydrase (PolyHb-SOD-CAT-CA) is a therapeutic antioxidant that also transports both oxygen and carbon dioxide. This is formed by crosslinking Hb with SOD, CAT, and CA using glutaraldehyde. Crosslinking stroma-free Hb from red blood cell (RBC) reduces CA activity to 55%. Addition of more CA resulted in a preparation with the same CA activity as RBC. PolyHb in the complex acts as a buffer to prevent large pH changes as carbon dioxide is converted to carbonic acid. We then prepare and optimize a novel PolyHb-SOD-CAT-CA, a therapeutic antioxidant that also transports both oxygen and carbon dioxide.

  2. Efficient androst-1,4-diene-3,17-dione production by co-expressing 3-ketosteroid-Δ1 -dehydrogenase and catalase in Bacillus subtilis.

    Science.gov (United States)

    Shao, M; Sha, Z; Zhang, X; Rao, Z; Xu, M; Yang, T; Xu, Z; Yang, S

    2017-01-01

    3-ketosteroid-Δ1 -dehydrogenase (KSDD), a flavin adenine dinucleotide (FAD)-dependent enzyme involved in sterol metabolism, specifically catalyses the conversion of androst-4-ene-3,17-dione (AD) to androst-1,4-diene-3,17-dione (ADD). However, the low KSDD activity and the toxic effects of hydrogen peroxide (H2 O2 ) generated during the biotransformation of AD to ADD with FAD regeneration hinder its application on AD conversion. The aim of this work was to improve KSDD activity and eliminate the toxic effects of the generated H2 O2 to enhance ADD production. The ksdd gene obtained from Mycobacterium neoaurum JC-12 was codon-optimized to increase its expression level in Bacillus subtilis, and the KSDD activity reached 12·3 U mg-1 , which was sevenfold of that of codon-unoptimized gene. To improve AD conversion, catalase was co-expressed with KSDD in B. subtilis 168/pMA5-ksddopt -katA to eliminate the toxic effects of H2 O2 generated during AD conversion. Finally, under optimized bioconversion conditions, fed-batch strategy was carried out and the ADD yield improved to 8·76 g l-1 . This work demonstrates the potential to improve enzyme activity by codon-optimization and eliminate the toxic effects of H2 O2 by co-expressing catalase. This study showed the highest ADD productivity ever reported and provides a promising strain for efficient ADD production in the pharmaceutical industry. © 2016 The Society for Applied Microbiology.

  3. Identification of YfiH and the Catalase CatA As Polyphenol Oxidases of Aeromonas media and CatA as a Regulator of Pigmentation by Its Peroxyl Radical Scavenging Capacity

    Science.gov (United States)

    Chai, Baozhong; Qiao, Yunqian; Wang, He; Zhang, Xiaoming; Wang, Jiao; Wang, Choushi; Zhou, Ping; Chen, Xiangdong

    2017-01-01

    Pyomelanin is the major constituent of pigment in melanogenic Aeromonas strains of bacteria. However, eumelanin, synthesized from tyrosine via L-DOPA and polyphenol oxidases (PPOs), may also be present in this genus since L-DOPA is frequently detected in culture fluids of several species. To address this question, we used a deletion mutant of Aeromonas media strain WS, in which pyomelanin synthesis is completely blocked under normal culture conditions. When tyrosine was supplied to the medium, we observed residual melanin accumulation, which we interpret as evidence for existence of the DOPA-melanin pathway. We traced enzymatic activity in this bacterium using native-polyacrylamide gel electrophoresis. Two PPOs: YfiH, a laccase-like protein, and CatA, a catalase, were identified. However, neither protein was critical for the residual pigmentation in pyomelanin-deficient mutant. We speculate that eumelanin synthesis may require other unknown enzymes. Deletion of yfiH did not affect pigmentation in A. media strain WS, while deletion of the CatA-encoding gene katE resulted in a reduction of melanin accumulation, but it started 9 h earlier than in the wild-type. Since catalases regulate reactive oxygen species levels during melanogenesis, we speculated that CatA affects pigmentation through its peroxyl radical scavenging capacity. Consistent with this, expression of the catalases Hpi or Hpii from Escherichia coli in the katE deletion strain of A. media strain WS restored pigmentation to the wild-type level. Hpi and Hpii also exhibited PPO activity, suggesting that catalase may represent a new class of PPOs. PMID:29051758

  4. The catalase C-262T gene polymorphism and cancer risk: a systematic review and meta-analysis.

    Science.gov (United States)

    Shen, Yongchun; Li, Diandian; Tian, Panwen; Shen, Konglong; Zhu, Jing; Feng, Mei; Wan, Chun; Yang, Ting; Chen, Lei; Wen, Fuqiang

    2015-04-01

    Many studies suggest that catalase C-262T gene polymorphism is associated with cancer risk, but with inconsistent results. This study aimed to summarize the overall association between catalase C-262T polymorphism and cancer risk. Literature search was performed in PubMed, Embase, and other databases, studies regarding the association between catalase C-262T polymorphism and cancer risk were identified, and data were retrieved and analyzed by using Review Manager 5.0.24 and STATA 12.0. A total of 18 publications with 22 case-control studies, including 9777 cancer patients and 12,223 controls, met the inclusion criteria. Meta-analysis results showed significant association between catalase C-262 T polymorphism and cancer risk (TT vs CT + CC: odds ratio [OR] = 1.17, 95% confidence interval [CI] = 1.03-1.31, P = 0.01). Subgroup analyses stratified by cancer types suggested the catalase C-262T polymorphism was significantly associated with an increased prostate cancer risk (TT vs CT + CC: OR = 1.61, 95% CI = 1.17-2.22, P = 0.004); for subgroup analyses stratified by ethnicity, no associations between this polymorphism and Asians or whites were identified (CT + TT vs CC: OR = 1.11, 95% CI = 0.98-1.26, P = 0.09 for whites; OR = 1.19, 95% CI = 0.78-1.80, P = 0.42 for Asians). In summary, the catalase C-262T polymorphism may be a risk factor for cancer with cancer type-specific effects. Further studies should be performed to confirm these findings.

  5. Catalase-positive microperoxisomes in rat soleus and extensor digitorum longus muscle fiber types

    Science.gov (United States)

    Riley, Danny A.; Bain, James L. W.; Ellis, Stanley

    1988-01-01

    The size, distribution, and content of catalase-reactive microperoxisomes were investigated cytochemically in three types of muscle fibers from the soleus and the extensor digitorum longus (EDL) of male rats. Muscle fibers were classified on the basis of the mitochondrial content and distribution, the Z-band widths, and the size and shape of myofibrils as the slow-twitch oxidative (SO), the fast-twitch oxidative glycolytic (FOG), and the fast-twitch glycolytic (FG) fibers. It was found that both the EDL and soleus SO fibers possessed the largest microperoxisomes. A comparison of microperoxisome number per muscle fiber area or the microperoxisome area per fiber area revealed following ranking, starting from the largest number and the area-ratio values: soleus SO, EDL SO, EDL FOG, and EDL FG.

  6. Lipopolysaccharide-stimulated Leukocytes Contribute to Platelet Aggregative Dysfunction, Which is Attenuated by Catalase in Rats

    Directory of Open Access Journals (Sweden)

    Huei-Ping Dong

    2010-11-01

    Full Text Available Endotoxemia causes several hematological dysfunctions, including platelet degranulation or disseminated intravascular coagulation, which lead to thrombotic and hemorrhagic events. Here, we tested the hypothesis that bacterial lipopolysaccharide (LPS-stimulated leukocytes contribute to platelet aggregative dysfunction, and this function is attenuated by antioxidants. Plateletrich plasma (PRP was prepared from whole blood of normal and endotoxemic rats. The ability of platelet aggregation was measured by an aggregometer. LPS (50–100 μg/mL was incubated with PRP, whole blood and PRP with polymorphonuclear leukocytes (PMNs for 30 minutes, 60 minutes and 90 minutes, and platelet aggregation was detected. LPS-induced platelet aggregative dysfunction was undetectable in intact PRP which was isolated from normal whole blood, whereas it was detected in PRP isolated from endotoxemic rats and LPS-treated whole blood. Moreover, the effect of LPS-induced platelet aggregative dysfunction on intact PRP was observed when the PMNs were added. LPS-induced platelet aggregative dysfunction was significantly attenuated by catalase alone and in combination with NG-nitro-L-arginine methyl ester, but not by NG-nitro-L-arginine methyl ester alone. These results indicate that LPS-stimulated PMNs modulate platelet aggregation during LPS treatment and the effects are reversed by antioxidants. PMNs serve as an approach to understand LPS-induced platelet aggregative dysfunction during endotoxemia. During this process, the generation of reactive oxygen species, hydrogen peroxide especially, from LPS-stimulated PMNs could be an important potential factor in LPS-induced platelet aggregative dysfunction. Catalase contributes to the prevention of platelet dysfunction during LPS-induced sepsis.

  7. Fipronil induced oxidative stress involves alterations in SOD1 and catalase gene expression in male mice liver: Protection by vitamins E and C.

    Science.gov (United States)

    Badgujar, Prarabdh C; Chandratre, Gauri A; Pawar, Nitin N; Telang, A G; Kurade, N P

    2016-09-01

    In the present investigation, hepatic oxidative stress induced by fipronil was evaluated in male mice. We also investigated whether pretreatment with antioxidant vitamins E and C could protect mice against these effects. Several studies conducted in cell lines have shown fipronil as a potent oxidant; however, no information is available regarding its oxidative stress inducing potential in an animal model. Out of 8 mice groups, fipronil was administered to three groups at low, medium, and high dose based on its oral LD50 (2.5, 5, and 10 mg/kg). All three doses of fipronil caused a significant increase in the serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) level with concomitant increase in the absolute and relative weight of liver. High dose of fipronil caused significant down-regulation in the hepatic mRNA expression of superoxide dismutase 1 (SOD1) and catalase (0.412 ± 0.01 and 0.376 ± 0.05-fold, respectively) as well as an increase in the lipid peroxidation (LPO). Also, decrease in the activity of antioxidant enzymes; SOD, catalase, and glutathione-S-transferase (GST) and the content of nonantioxidant enzymes; glutathione and total thiol were recorded. Histopathological examination of liver revealed dose dependant changes such as severe fatty degeneration and vacuolation leading to hepatocellular necrosis. Prior administration of vitamin E or vitamin C against fipronil high dose caused decrease in lipid peroxidation and increased activity of antioxidant enzymes. Severe reduction observed in functional activities of antioxidant enzymes was aptly substantiated by down-regulation seen in their relative mRNA expression. Thus results of the present study imply that liver is an important target organ for fipronil and similar to in vitro reports, it induces oxidative stress in the mice liver, which in turn could be responsible for its hepatotoxic nature. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1147-1158, 2016. © 2015

  8. Ultrasensitive fluorescence immunoassay for detection of ochratoxin A using catalase-mediated fluorescence quenching of CdTe QDs

    Science.gov (United States)

    Huang, Xiaolin; Zhan, Shengnan; Xu, Hengyi; Meng, Xianwei; Xiong, Yonghua; Chen, Xiaoyuan

    2016-04-01

    Herein, for the first time we report an improved competitive fluorescent enzyme linked immunosorbent assay (ELISA) for the ultrasensitive detection of ochratoxin A (OTA) by using hydrogen peroxide (H2O2)-induced fluorescence quenching of mercaptopropionic acid-modified CdTe quantum dots (QDs). In this immunoassay, catalase (CAT) was labeled with OTA as a competitive antigen to connect the fluorescence signals of the QDs with the concentration of the target. Through the combinatorial use of H2O2-induced fluorescence quenching of CdTe QDs as a fluorescence signal output and the ultrahigh catalytic activity of CAT to H2O2, our proposed method could be used to perform a dynamic linear detection of OTA ranging from 0.05 pg mL-1 to 10 pg mL-1. The half maximal inhibitory concentration was 0.53 pg mL-1 and the limit of detection was 0.05 pg mL-1. These values were approximately 283- and 300-folds lower than those of horseradish peroxidase (HRP)-based conventional ELISA, respectively. The reported method is accurate, highly reproducible, and specific against other mycotoxins in agricultural products as well. In summary, the developed fluorescence immunoassay based on H2O2-induced fluorescence quenching of CdTe QDs can be used for the rapid and highly sensitive detection of mycotoxins or haptens in food safety monitoring.Herein, for the first time we report an improved competitive fluorescent enzyme linked immunosorbent assay (ELISA) for the ultrasensitive detection of ochratoxin A (OTA) by using hydrogen peroxide (H2O2)-induced fluorescence quenching of mercaptopropionic acid-modified CdTe quantum dots (QDs). In this immunoassay, catalase (CAT) was labeled with OTA as a competitive antigen to connect the fluorescence signals of the QDs with the concentration of the target. Through the combinatorial use of H2O2-induced fluorescence quenching of CdTe QDs as a fluorescence signal output and the ultrahigh catalytic activity of CAT to H2O2, our proposed method could be used to

  9. Ethanol induced attenuation of oxidative stress is unable to alter mRNA expression pattern of catalase, glutathione reductase, glutathione-S- transferase (GST1A), and superoxide dismutase (SOD3) enzymes in Japanese rice fish (Oryzias latipes) embryogenesis

    Science.gov (United States)

    Wu, Minghui; Shariat-Madar, Bahbak; Haron, Mona H.; Wu, Mengmeng; Khan, Ikhlas A.; Dasmahapatra, Asok K.

    2010-01-01

    Although the mechanism of ethanol toxicity during embryogenesis is unknown, our earlier studies on Japanese rice fish (Oryzias latipes) embryos indicated that the effects might be mediated through oxidative stress. In this study we have determined the oxidative stress and the mRNA content of four antioxidant enzymes (catalase, glutathione reductase, glutathione-S-transferase, and superoxide dismutase) during Japanese rice fish embryogenesis (from 0 day post-fertilization to hatching) and after exposing the embryos to ethanol (100 and 300 mM) for 48 h at three stages (0–2, 1–3 and 4–6 day post fertilization, dpf) of organogenesis. We observed that oxidative stress was minimal in blastula, gastrula or neurula stages, increased gradually with the advancement of morphogenesis and reached its maximum level in hatchlings. The antioxidant enzyme mRNAs were constitutively expressed throughout development; however, the expression pattern was not identical among the enzymes. Catalase and superoxide dismutase (SOD) mRNAs were minimal in the fertilized eggs, but increased significantly in 1 dpf and then either sharply dropped (SOD) or maintained a steady-state (catalase). Glutathione S-transferase (GST) was very high in fertilized eggs and sharply dropped 1 dpf and then gradually increased thereafter. Glutathione reductase (GR) maintained a steady-state throughout the development. Ethanol was able to attenuate oxidative stress in embryos exposed only to 300 mM 1–3 dpf; no significant difference with controls was observed in other ethanol-treated groups. The antioxidant enzyme mRNAs also remained unaltered after ethanol treatment. From these data we conclude that the attenuation of oxidative stress by ethanol is probably due to the inhibition of normal growth of the embryos rather than by inhibiting catalase, GST, GR or SOD- dependent activities. PMID:20965276

  10. Ethanol-induced attenuation of oxidative stress is unable to alter mRNA expression pattern of catalase, glutathione reductase, glutathione-S-transferase (GST1A), and superoxide dismutase (SOD3) enzymes in Japanese rice fish (Oryzias latipes) embryogenesis.

    Science.gov (United States)

    Wu, Minghui; Shariat-Madar, Bahbak; Haron, Mona H; Wu, Mengmeng; Khan, Ikhlas A; Dasmahapatra, Asok K

    2011-01-01

    Although the mechanism of ethanol toxicity during embryogenesis is unknown, our earlier studies on Japanese rice fish (Oryzias latipes) embryos indicated that the effects might be mediated through oxidative stress. In this study we have determined the oxidative stress and the mRNA content of four antioxidant enzymes (catalase, glutathione reductase, glutathione-S-transferase, and superoxide dismutase) during Japanese rice fish embryogenesis (from 0 day post-fertilization to hatching) and after exposing the embryos to ethanol (100 and 300 mM) for 48 h at three stages (0-2, 1-3 and 4-6 days post-fertilization, dpf) of organogenesis. We observed that oxidative stress was minimal in blastula, gastrula or neurula stages, increased gradually with the advancement of morphogenesis and reached its maximum level in hatchlings. The antioxidant enzyme mRNAs were constitutively expressed throughout development; however, the expression pattern was not identical among the enzymes. Catalase and superoxide dismutase (SOD) mRNAs were minimal in the fertilized eggs, but increased significantly in 1 dpf and then either sharply dropped (SOD) or maintained a steady-state (catalase). Glutathione-S-transferase (GST) was very high in fertilized eggs and sharply dropped 1 dpf and then gradually increased thereafter. Glutathione reductase (GR) maintained a steady-state throughout the development. Ethanol was able to attenuate oxidative stress in embryos exposed only to 300 mM 1-3 dpf; no significant difference with controls was observed in other ethanol-treated groups. The antioxidant enzyme mRNAs also remained unaltered after ethanol treatment. From these data we conclude that the attenuation of oxidative stress by ethanol is probably due to the inhibition of normal growth of the embryos rather than by inhibiting catalase, GST, GR or SOD-dependent activities. Published by Elsevier Inc.

  11. Effects of Aging and Oxidative Stress on Spermatozoa of Superoxide-Dismutase 1- and Catalase-Null Mice.

    Science.gov (United States)

    Selvaratnam, Johanna S; Robaire, Bernard

    2016-09-01

    Advanced paternal age is linked to complications in pregnancy and genetic diseases in offspring. Aging results in excess reactive oxygen species (ROS) and DNA damage in spermatozoa; this damage can be transmitted to progeny with detrimental consequences. Although there is a loss of antioxidants with aging, the impact on aging male germ cells of the complete absence of either catalase (CAT) or superoxide dismutase 1 (SOD1) has not been investigated. We used CAT-null (Cat(-/-)) and SOD1-null (Sod(-/-)) mice to determine whether loss of these antioxidants increases germ cell susceptibility to redox dysfunction with aging. Aging reduced fertility and the numbers of Sertoli and germ cells in all mice. Aged Sod(-/-) mice displayed an increased loss of fertility compared to aged wild-type mice. Treatment with the pro-oxidant SIN-10 increased ROS in spermatocytes of aged wild-type and Sod(-/-) mice, while aged Cat(-/-) mice were able to neutralize this ROS. The antioxidant peroxiredoxin 1 (PRDX1) increased with age in wild-type and Cat(-/-) mice but was consistently low in young and aged Sod(-/-) mice. DNA damage and repair markers (γ-H2AX and 53BP1) were reduced with aging and lower in young Sod(-/-) and Cat(-/-) mice. Colocalization of γ-H2AX and 53BP1 suggested active repair in young wild-type mice but reduced in young Cat(-/-) and in Sod(-/-) mice and with age. Oxidative DNA damage (8-oxodG) increased in young Sod(-/-) mice and with age in all mice. These studies show that aged Sod(-/-) mice display severe redox dysfunction, while wild-type and Cat(-/-) mice have compensatory mechanisms to partially alleviate oxidative stress and reduce age-related DNA damage in spermatozoa. Thus, SOD1 but not CAT is critical to the maintenance of germ cell quality with aging. © 2016 by the Society for the Study of Reproduction, Inc.

  12. Metal-based superoxide dismutase and catalase mimics reduce oxidative stress biomarkers and extend life span of Saccharomyces cerevisiae.

    Science.gov (United States)

    Ribeiro, Thales de P; Fonseca, Fernanda L; de Carvalho, Mariana D C; Godinho, Rodrigo M da C; de Almeida, Fernando Pereira; Saint'Pierre, Tatiana D; Rey, Nicolás A; Fernandes, Christiane; Horn, Adolfo; Pereira, Marcos D

    2017-01-15

    Aging is a natural process characterized by several biological changes. In this context, oxidative stress appears as a key factor that leads cells and organisms to severe dysfunctions and diseases. To cope with reactive oxygen species and oxidative-related damage, there has been increased use of superoxide dismutase (SOD)/catalase (CAT) biomimetic compounds. Recently, we have shown that three metal-based compounds {[Fe(HPClNOL)Cl2]NO3, [Cu(HPClNOL)(CH3CN)](ClO4)2 and Mn(HPClNOL)(Cl)2}, harboring in vitro SOD and/or CAT activities, were critical for protection of yeast cells against oxidative stress. In this work, treating Saccharomyces cerevisiae with these SOD/CAT mimics (25.0 µM/1 h), we highlight the pivotal role of these compounds to extend the life span of yeast during chronological aging. Evaluating lipid and protein oxidation of aged cells, it becomes evident that these mimics extend the life expectancy of yeast mainly due to the reduction in oxidative stress biomarkers. In addition, the treatment of yeast cells with these mimics regulated the amounts of lipid droplet occurrence, consistent with the requirement and protection of lipids for cell integrity during aging. Concerning SOD/CAT mimics uptake, using inductively coupled plasma mass spectrometry, we add new evidence that these complexes, besides being bioabsorbed by S. cerevisiae cells, can also affect metal homeostasis. Finally, our work presents a new application for these SOD/CAT mimics, which demonstrate a great potential to be employed as antiaging agents. Taken together, these promising results prompt future studies concerning the relevance of administration of these molecules against the emerging aging-related diseases such as Parkinson's, Alzheimer's and Huntington's. © 2017 The Author(s); published by Portland Press Limited on behalf of the Biochemical Society.

  13. A facile and efficient method of enzyme immobilization on silica particles via Michael acceptor film coatings: immobilized catalase in a plug flow reactor.

    Science.gov (United States)

    Bayramoglu, Gulay; Arica, M Yakup; Genc, Aysenur; Ozalp, V Cengiz; Ince, Ahmet; Bicak, Niyazi

    2016-06-01

    A novel method was developed for facile immobilization of enzymes on silica surfaces. Herein, we describe a single-step strategy for generating of reactive double bonds capable of Michael addition on the surfaces of silica particles. This method was based on reactive thin film generation on the surfaces by heating of impregnated self-curable polymer, alpha-morpholine substituted poly(vinyl methyl ketone) p(VMK). The generated double bonds were demonstrated to be an efficient way for rapid incorporation of enzymes via Michael addition. Catalase was used as model enzyme in order to test the effect of immobilization methodology by the reactive film surface through Michael addition reaction. Finally, a plug flow type immobilized enzyme reactor was employed to estimate decomposition rate of hydrogen peroxide. The highly stable enzyme reactor could operate continuously for 120 h at 30 °C with only a loss of about 36 % of its initial activity.

  14. Infantile Refsum disease: deficiency of catalase-containing particles (peroxisomes), alkyldihydroxyacetone phosphate synthase and peroxisomal beta-oxidation enzyme proteins

    NARCIS (Netherlands)

    Wanders, R. J.; Schutgens, R. B.; Schrakamp, G.; van den Bosch, H.; Tager, J. M.; Schram, A. W.; Hashimoto, T.; Poll-Thé, B. T.; Saudubrau, J. M.

    1986-01-01

    In recent years a number of biochemical abnormalities have been described in patients with the infantile form of Refsum disease, including the accumulation of very long chain fatty acids, trihydroxycoprostanoic acid and pipecolic acid. In this paper we show that catalase-containing particles

  15. Horizontal gene transfer confers adaptive advantages to phytopathogenic fungi: a case study of catalase-peroxidase in Fusarium verticillioides

    Science.gov (United States)

    Horizontal gene transfer (HGT), the exchange and stable integration of genetic material between different evolutionary lineages, is widely observed in fungi. We hypothesize that successful stabilization of HGT elements provides adaptive advantages (e.g., virulence). Catalase/peroxidases (KatGs) are ...

  16. Cloning and expression of the catalase-peroxidase gene from the hyperthermophilic archaeon Archaeoglobus fulgidus and characterization of the enzyme

    NARCIS (Netherlands)

    Kengen, S.W.M.; Bikker, F.; Vos, de W.M.; Oost, van der J.

    2001-01-01

    A putative perA gene from Archaeoglobus fulgidus was cloned and expressed in Escherichia coli BL21(DE3), and the recombinant catalase-peroxidase was purified to homogeneity. The enzyme is a homodimer with a subunit molecular mass of 85 kDa. UV-visible spectroscopic analysis indicated the presence of

  17. Teaching Enzymes to Pre-Service Science Teachers through POE (Predict, Observe, Explain) Method: The Case of Catalase

    Science.gov (United States)

    Güngör, Sema Nur; Özkan, Muhlis

    2016-01-01

    The aim of this study is to teach enzymes, which are one of the biology subjects in understanding which students have a big difficulty, to pre-service teachers through POE method in the case of catalase, which is an oxidoreductase. Descriptive analysis method was employed in this study in which 38 second grade pre-service teachers attending Uludag…

  18. Characterisation by Impedance Spectroscopy and Capacitance-Voltage of an EMIS Sensor Functionalized by Catalase for Nitrite Detection

    Directory of Open Access Journals (Sweden)

    A. ZAZOUA

    2014-05-01

    Full Text Available Impedance spectroscopy and capacitance-voltage (C-V methods are a rapidly developing electrochemical technique for the characterization of biomaterial–functionalized electrodes and biocatalytic transformations on the electrodes surface, and specifically for the transduction of biosensing events at electrodes. Such techniques have been used in our work as a tool for the characterization of a new nitrite biosensor for environmental applications based on the immobilization of catalase on insulator-semiconductor (IS systems (p-Si/SiO2/Si3N4. The principle of the developed biosensor includes the following: Catalase catalyzed the breakdown of H2O2 into H2O and O2. Nitrite was selected as an inhibitor of catalase. Under optimal conditions, i.e. buffer capacity corresponding to 3 mM phosphate buffer, the catalase enzyme insulator semiconductor sensors shows a high sensitivity to nitrite detection. In both cases, the responses of these biosensors based on nitrite additions are good with the detection limit around 10-11 M. It is expected that such an original and promising concept of inhibitor-based biosensors based on reactivation by inhibitive effects, will be useful for the development of environmental smart biosensors based on the integration of ENFET with the corresponding instrumentation in the same silicon chip.

  19. The Antitumor Effect of Single-domain Antibodies Directed Towards Membrane-associated Catalase and Superoxide Dismutase.

    Science.gov (United States)

    Bauer, Georg; Motz, Manfred

    2016-11-01

    Neutralizing single-domain antibodies directed towards catalase or superoxide dismutase (SOD) caused efficient reactivation of intercellular reactive oxygen species/reactive nitrogen species (ROS/RNS)-dependent apoptosis-inducing signaling specifically in human tumor cells. Single-domain antibodies targeted tumor cell-specific membrane-associated SOD and catalase, but not the corresponding intracellular enzymes. They were shown to be about 200-fold more effective than corresponding classical recombinant antigen-binding fragments and more than four log steps more efficient than monoclonal antibodies. Combined addition of single-domain antibodies against catalase and SOD caused a remarkable synergistic effect. Proof-of-concept experiments in immunocompromised mice using human tumor