These are representative sample records from related to your search topic.
For comprehensive and current results, perform a real-time search at

A rapid and transient ROS generation by cadmium triggers apoptosis via caspase-dependent pathway in HepG2 cells and this is inhibited through N-acetylcysteine-mediated catalase upregulation  

SciTech Connect

Although reactive oxygen species (ROS) have been implicated in cadmium (Cd)-induced hepatotoxicity, the role of ROS in this pathway remains unclear. Therefore, we attempted to determine the molecular mechanisms relevant to Cd-induced cell death in HepG2 cells. Cd was found to induce apoptosis in the HepG2 cells in a time- and dose-dependent fashion, as confirmed by DNA fragmentation analysis and TUNEL staining. In the early stages, both rapid and transient ROS generation triggered apoptosis via Fas activation and subsequent caspase-8-dependent Bid cleavage, as well as by calpain-mediated mitochondrial Bax cleavage. The timing of Bid activation was coincided with the timing at which the mitochondrial transmembrane potential (MMP) collapsed as well as the cytochrome c (Cyt c) released into the cytosol. Furthermore, mitochondrial permeability transition (MPT) pore inhibitors, such as cyclosporin A (CsA) and bongkrekic acid (BA), did not block Cd-induced ROS generation, MMP collapse and Cyt c release. N-acetylcysteine (NAC) pretreatment resulted in the complete inhibition of the Cd-induced apoptosis via catalase upregulation and subsequent Fas downregulation. NAC treatment also completely blocked the Cd-induced intracellular ROS generation, MMP collapse and Cyt c release, indicating that Cd-induced mitochondrial dysfunction may be regulated indirectly by ROS-mediated signaling pathway. Taken together, a rapid and transient ROS generation by Cd triggers apoptosis via caspase-dependent pathway and subsequent mitochondrial pathway. NAC inhibits Cd-induced apoptosis through the blocking of ROS generation as well as the catalase upregulation.

Oh, Seon-Hee [Research Center for Resistant Cells, College of Medicine, Chosun University, Seosuk-dong, Dong-gu, Gwangju 501-759 (Korea, Republic of); Lim, Sung-Chul [Research Center for Resistant Cells, College of Medicine, Chosun University, Seosuk-dong, Dong-gu, Gwangju 501-759 (Korea, Republic of) and Department of Pathology, College of Medicine, Chosun University, Seosuk-dong, Dong-gu, Gwangju 501-759 (Korea, Republic of)]. E-mail:



Catalase Test Protocol  

NSDL National Science Digital Library

The catalase test is used to detect the presence of the enzyme catalase in bacteria. Catalase serves to neutralize the bactericidal effects of hydrogen peroxide. Its concentration in bacteria has been correlated with pathogenicity. This enzymatic test is essential in the scheme of identification for gram-positive organisms and certain gram-negative organisms. It is a primary test used in the differentiation of staphylococci and streptococci.

American Society For Microbiology;



Cancer and Human Liver Catalase  

Microsoft Academic Search

SUMMARY Data presented in the present paper indicate that human liver catalase depression is related to weight loss. A statistical study was first made to determine the catalase activity in correlation of the iodotitrimetric and spectrophotometric methods for biopsy and autopsy samples from cancer and cancer-free patients. Cancer patients had a 2~ per cent lower liver catalase activity than cancer-free




In vitro assembly of catalase.  


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

Baureder, Michael; Barane, Elisabeth; Hederstedt, Lars



High Dietary Fat Selectively Increases Catalase Expression within Cardiac Mitochondria*  

PubMed Central

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

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



Molecular evolution of maize catalases and their relationship to other eukaryotic and prokaryotic catalases  

Microsoft Academic Search

We have compared the nucleotide and protein sequences of the three maize catalase genes with other plant catalases to reconstruct\\u000a the evolutionary relationship among these catalases. These sequences were also compared with other eukaryotic and prokaryotic\\u000a catalases. Phylogenies based on distances and parsimony analysis show that all plant catalases derive from a common ancestral\\u000a catalase gene and can be divided

Lingqiang Guan; John G. Scandalios



The Role of Catalase in Pulmonary Fibrosis  

Microsoft Academic Search

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

Nao Odajima; Tomoko Betsuyaku; Katsura Nagai; Chinatsu Moriyama; Da-Hong Wang; Tomoko Takigawa; Keiki Ogino; Masaharu Nishimura



Catalase activity and innate immune response of Caenorhabditis elegans against the heavy metal toxin lead.  


The heavy metal lead-induced oxidative stress on Caenorhabditis elegans was examined at the level of catalase activity and on innate immunity. Stress-induced C. elegans was exposed to Pseudomonas aeruginosa PA14::GFP for monitoring the impact at the physiological level. Role of catalase on the innate-immune responses of C. elegans was examined. PA14::GFP did not colonize lead pretreated C. elegans intestinal cells significantly compared to untreated controls, indicating stress-mediated upregulation of host-immunity. Semiquantitative PCR analyses of lead-exposed and PA14-infected C. elegans mRNA showed significant upregulation of candidate antimicrobial enzyme gene lys-7 after 24 h of exposures. Upregulation of metallothionein(mtl-1) when compared to mtl-2 in response to the lead suggesting active detoxification of metal by mtl-1. Exogenously provided Catalase (0.4-3.2 U) induced significant upregulation of lys-7 compared to controls. lys-7 upregulation during lead exposure was reconfirmed by real-time PCR. Confocal microscopy and fluorescence spectrophotometer analyses indicated that the lead pretreated C. elegans was significantly less colonized by PA14::GFP when compared to controls. Relative expression of ctl-1 and ctl-2 mRNA was measured using real time PCR and found to be regulated during lead exposures. Over all, the upregulation of antimicrobial gene expression appears to be correlated with the level of catalase during stress emphasizing their key roles in defensive mechanism(s). These results provide a link between the stress and related immune responses which can be explored in higher systems. PMID:21656642

Vigneshkumar, Balasubramanian; Pandian, Shunmugiah Karutha; Balamurugan, Krishnaswamy



Sirt1 protects against oxidative stress-induced renal tubular cell apoptosis by the bidirectional regulation of catalase expression  

SciTech Connect

NAD{sup +}-dependent protein deacetylase Sirt1 regulates cellular apoptosis. We examined the role of Sirt1 in renal tubular cell apoptosis by using HK-2 cells, proximal tubular cell lines with or without reactive oxygen species (ROS), H{sub 2}O{sub 2}. Without any ROS, Sirt1 inhibitors enhanced apoptosis and the expression of ROS scavenger, catalase, and Sirt1 overexpression downregulated catalase. When apoptosis was induced with H{sub 2}O{sub 2}, Sirt1 was upregulated with the concomitant increase in catalase expression. Sirt1 overexpression rescued H{sub 2}O{sub 2}-induced apoptosis through the upregulation of catalase. H{sub 2}O{sub 2} induced the nuclear accumulation of forkhead transcription factor, FoxO3a and the gene silencing of FoxO3a enhanced H{sub 2}O{sub 2}-induced apoptosis. In conclusion, endogenous Sirt1 maintains cell survival by regulating catalase expression and by preventing the depletion of ROS required for cell survival. In contrast, excess ROS upregulates Sirt1, which activates FoxO3a and catalase leading to rescuing apoptosis. Thus, Sirt1 constitutes a determinant of renal tubular cell apoptosis by regulating cellular ROS levels.

Hasegawa, Kazuhiro [Department of Internal Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 1608582 (Japan); Wakino, Shu [Department of Internal Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 1608582 (Japan)], E-mail:; Yoshioka, Kyoko; Tatematsu, Satoru; Hara, Yoshikazu; Minakuchi, Hitoshi; Washida, Naoki; Tokuyama, Hirobumi; Hayashi, Koichi; Itoh, Hiroshi [Department of Internal Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 1608582 (Japan)



Catalases play differentiated roles in the adaptation of a fungal entomopathogen to environmental stresses.  


The catalase family of Beauveria bassiana (fungal entomopathogen) consists of catA (spore-specific), catB (secreted), catP (peroxisomal), catC (cytoplasmic) and catD (secreted peroxidase/catalase), which were distinguished in phylogeny and structure and functionally characterized by constructing single-gene disrupted and rescued mutants for enzymatic and multi-phenotypic analyses. Total catalase activity decreased 89% and 56% in ?catB and ?catP, corresponding to the losses of upper and lower active bands gel-profiled for all catalases respectively, but only 9-12% in other knockout mutants. Compared with wild type and complement mutants sharing similar enzymatic and phenotypic parameters, all knockout mutants showed significant (9-56%) decreases in the antioxidant capability of their conidia (active ingredients of mycoinsecticides), followed by remarkable phenotypic defects associated with the fungal biocontrol potential. These defects included mainly the losses of 40% thermotolerance (45°C) in ?catA, 46-48% UV-B resistance in ?catA and ?catD, and 33-47% virulence to Spodoptera litura larvae in ?catA, ?catP and ?catD respectively. Moreover, the drastic transcript upregulation of some other catalase genes observed in the normal culture of each knockout mutant revealed functionally complimentary effects among some of the catalase genes, particularly between catB and catC whose knockout mutants displayed little or minor phenotypic changes. However, the five catalase genes functioned redundantly in mediating the fungal tolerance to either hyperosmotic or fungicidal stress. The differentiated roles of five catalases in regulating the B.?bassiana virulence and tolerances to oxidative stress, high temperature and UV-B irradiation provide new insights into fungal adaptation to stressful environment and host invasion. PMID:22891860

Wang, Zheng-Liang; Zhang, Long-Bin; Ying, Sheng-Hua; Feng, Ming-Guang



Catalase and NO CATALASE ACTIVITY1 Promote Autophagy-Dependent Cell Death in ArabidopsisC W OPEN  

E-print Network

Catalase and NO CATALASE ACTIVITY1 Promote Autophagy-Dependent Cell Death in ArabidopsisC W OPEN be detoxified by antioxidative enzymes, including catalases. We previously isolated catalase-deficient mutants triggered by the bacterial effector avrRpm1. To test if catalase deficiency likewise affected both

Schierup, Mikkel Heide


Immobilization of bovine catalase onto magnetic nanoparticles.  


The scope of this study is to achieve carrier-bound immobilization of catalase onto magnetic particles (Fe?O? and Fe?O?NiO? · H?O) to specify the optimum conditions of immobilization. Removal of H2O2 and the properties of immobilized sets were also investigated. To that end, adsorption and then cross-linking methods onto magnetic particles were performed. The optimum immobilization conditions were found for catalase: immobilization time (15 min for Fe?O?; 10 min for Fe2O?NiO? · H?O), the initial enzyme concentration (1 mg/mL), amount of magnetic particles (25 mg), and glutaraldehyde concentration (3%). The activity reaction conditions (optimum temperature, optimum pH, pH stability, thermal stability, operational stability, and reusability) were characterized. Also kinetic parameters were calculated by Lineweaver-Burk plots. The optimum pH values were found to be 7.0, 7.0, and 8.0 for free enzyme, Fe?O?-immobilized catalases, and Fe?O?NiO? · H?O-immobilized catalases, respectively. All immobilized catalase systems displayed the optimum temperature between 25 and 35°C. Reusability studies showed that Fe?O?-immobilized catalase can be used 11 times with 50% loss in original activity, while Fe2O?NiO? · H?O-immobilized catalase lost 67% of activity after the same number of uses. Furthermore, immobilized catalase systems exhibited improved thermal and pH stability. The results transparently indicate that it is possible to have binding between enzyme and magnetic nanoparticles. PMID:23876136

Do?aç, Yasemin ?spirli; Teke, Mustafa



cDNA cloning, characterization and expression analysis of the antioxidant enzyme gene, catalase, of Chinese shrimp Fenneropenaeus chinensis.  


Catalase is an important antioxidant protein that protects organisms against various oxidative stresses by eliminating hydrogen peroxide. The full-length catalase cDNA of Chinese shrimp Fenneropenaeus chinensis was cloned from the hepatopancreas using degenerate primers by the method of 3' and 5' rapid amplification of cDNA ends PCR. The cDNA sequence consists of 1892 bp with a 1560 bp open reading frame, encoding 520 amino acids with high identity to invertebrate, vertebrate and even bacterial catalases. The sequence includes the catalytic residues His71, Asn144, and Tyr354. The molecular mass of the predicted protein is 58824.04 Da with an estimated pI of 6.63. Sequence comparison showed that the deduced amino acid sequence of F. chinensis catalase shares 96%, 73%, 71% and 70% identity with that of Pacific white shrimp Litopenaeus vannamei, Abalone Haliotis discus hannai, Zhikong scallop Chlamys farreri and Human Homo sapiens, respectively. Catalase transcripts were detected in hepatopancreas, hemocytes, lymphoid organ, intestine, ovary, muscle and gill by real-time PCR. The variation of catalase mRNA transcripts in hemocytes and hepatopancreas was also quantified by real-time PCR and the result indicated that the catalase showed up-regulated expression trends in hemocytes at 14 h and in hepatopancreas at 37 h after injection with white spot syndrome virus (WSSV). PMID:18353680

Zhang, Qingli; Li, Fuhua; Zhang, Xiaojun; Dong, Bo; Zhang, Jiquan; Xie, Yusu; Xiang, Jianhai



[Noncovalent immobilization of catalase on antibodies adsorbed on carbon fabric].  


Catalase was immobilized on an immunosorbent prepared by anticatalase adsorption on an activated carbon fabric (ACF), and its kinetic parameters were determined. The immobilized catalase activity depended on the binding capacity of anticatalase. Under the optimum conditions (6 micrograms/mg anticatalase, 5.24 nM catalase) the immobilized catalase activity was 1.5-ford higher as compared to soluble catalase. Antibodies stabilized soluble catalase, but decreased its thermostability on immobilization of immunocomplexes on ACF. Noncovalent immobilization of catalase on adsorbed antibodies opens up the way to the use of this approach for immobilization of other oligomeric enzymes. PMID:7984550

Litvinchuk, A V; Morozova, A A; Savenkova, M I; Metelitsa, D I



Discovery of Catalases in Members of the Chlamydiales Order  

PubMed Central

Catalase is an important virulence factor for survival in macrophages and other phagocytic cells. In Chlamydiaceae, no catalase had been described so far. With the sequencing and annotation of the full genomes of Chlamydia-related bacteria, the presence of different catalase-encoding genes has been documented. However, their distribution in the Chlamydiales order and the functionality of these catalases remain unknown. Phylogeny of chlamydial catalases was inferred using MrBayes, maximum likelihood, and maximum parsimony algorithms, allowing the description of three clade 3 and two clade 2 catalases. Only monofunctional catalases were found (no catalase-peroxidase or Mn-catalase). All presented a conserved catalytic domain and tertiary structure. Enzymatic activity of cloned chlamydial catalases was assessed by measuring hydrogen peroxide degradation. The catalases are enzymatically active with different efficiencies. The catalase of Parachlamydia acanthamoebae is the least efficient of all (its catalytic activity was 2 logs lower than that of Pseudomonas aeruginosa). Based on the phylogenetic analysis, we hypothesize that an ancestral class 2 catalase probably was present in the common ancestor of all current Chlamydiales but was retained only in Criblamydia sequanensis and Neochlamydia hartmannellae. The catalases of class 3, present in Estrella lausannensis and Parachlamydia acanthamoebae, probably were acquired by lateral gene transfer from Rhizobiales, whereas for Waddlia chondrophila they likely originated from Legionellales or Actinomycetales. The acquisition of catalases on several occasions in the Chlamydiales suggests the importance of this enzyme for the bacteria in their host environment. PMID:23729651

Rusconi, Brigida



Protective Role of Catalase in Pseudomonas aeruginosa Biofilm Resistance to Hydrogen Peroxide  

PubMed Central

The role of the two known catalases in Pseudomonas aeruginosa in protecting planktonic and biofilm cells against hydrogen peroxide (H2O2) was investigated. Planktonic cultures and biofilms formed by the wild-type strain PAO1 and the katA and katB catalase mutants were compared for their susceptibility to H2O2. Over the course of 1 h, wild-type cell viability decreased steadily in planktonic cells exposed to a single dose of 50 mM H2O2, whereas biofilm cell viability remained at approximately 90% when cells were exposed to a flowing stream of 50 mM H2O2. The katB mutant, lacking the H2O2-inducible catalase KatB, was similar to the wild-type strain with respect to H2O2 resistance. The katA mutant possessed undetectable catalase activity. Planktonic katA mutant cultures were hypersusceptible to a single dose of 50 mM H2O2, while biofilms displayed a 10-fold reduction in the number of culturable cells after a 1-h exposure to 50 mM H2O2. Catalase activity assays, activity stains in nondenaturing polyacrylamide gels, and lacZ reporter genes were used to characterize the oxidative stress responses of planktonic cultures and biofilms. Enzyme assays and catalase activity bands in nondenaturing polyacrylamide gels showed significant KatB catalase induction occurred in biofilms after a 20-min exposure to H2O2, suggesting that biofilms were capable of a rapid adaptive response to the oxidant. Reporter gene data obtained with a katB::lacZ transcriptional reporter strain confirmed katB induction and that the increase in total cellular catalase activity was attributable to KatB. Biofilms upregulated the reporter in the constant presence of 50 mM H2O2, while planktonic cells were overwhelmed by a single 50 mM dose and were unable to make detectable levels of ?-galactosidase. The results of this study demonstrated the following: the constitutively expressed KatA catalase is important for resistance of planktonic and biofilm P. aeruginosa to H2O2, particularly at high H2O2 concentrations; KatB is induced in both planktonic and biofilm cells in response to H2O2 insult, but plays a relatively small role in biofilm resistance; and KatB is important to either planktonic cells or biofilm cells for acquired antioxidant resistance when initial levels of H2O2 are sublethal. PMID:10508094

Elkins, James G.; Hassett, Daniel J.; Stewart, Philip S.; Schweizer, Herbert P.; McDermott, Timothy R.



Breaking of Seed Dormancy by Catalase Inhibition  

Microsoft Academic Search

Germination of some dormant seeds is promoted by solutions of thiourea, sodium nitrite, and hydroxylamine salts. The promotions are accompanied by irreversible inhibition of catalase (EC in extracts from the seeds. The seeds are also promoted in germination by catechol and pyrogallol solutions. These effects are recorded for lettuce (Lactuca sativa L. cv. Grand Rapids) and pigweed (Amaranthus albus

S. B. Hendricks; R. B. Taylorson



Structural features of peroxisomal catalase from the yeast Hansenula polymorpha.  


The reactive oxygen species hydrogen peroxide is a byproduct of the ?-oxidation process that occurs in peroxisomes. Since reactive oxygen species can cause serious damage to biomolecules, a number of scavengers control their intracellular levels. One such scavenger that is present in the peroxisome is the oxidoreductase catalase. In this study, the crystal structure of heterologously expressed peroxisomal catalase from the thermotolerant yeast Hansenula polymorpha has been determined at 2.9?Å resolution. H. polymorpha catalase is a typical peroxisomal catalase; it is tetrameric and is highly similar to catalases from other organisms. However, its hydrogen peroxide-degrading activity is higher than those of a number of other catalases for which structural data are available. Structural superimpositions indicate that the nature of the major channel, the path for hydrogen peroxide to the active site, varies from those seen in other catalase structures, an observation that may account for the high activity of H. polymorpha catalase. PMID:21795810

Peña-Soler, Esther; Vega, M Cristina; Wilmanns, Matthias; Williams, Chris



21 CFR 173.135 - Catalase derived from Micrococcus lysodeikticus.  

Code of Federal Regulations, 2014 CFR

...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) SECONDARY DIRECT FOOD ADDITIVES PERMITTED IN FOOD FOR HUMAN CONSUMPTION Enzyme Preparations and Microorganisms § 173.135 Catalase derived from Micrococcus lysodeikticus. Bacterial catalase...



21 CFR 173.135 - Catalase derived from Micrococcus lysodeikticus.  

Code of Federal Regulations, 2013 CFR

...CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) SECONDARY DIRECT FOOD ADDITIVES PERMITTED IN FOOD FOR HUMAN CONSUMPTION Enzyme Preparations and Microorganisms § 173.135 Catalase derived from Micrococcus lysodeikticus. Bacterial catalase...



21 CFR 173.135 - Catalase derived from Micrococcus lysodeikticus.  

Code of Federal Regulations, 2012 CFR

...CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) SECONDARY DIRECT FOOD ADDITIVES PERMITTED IN FOOD FOR HUMAN CONSUMPTION Enzyme Preparations and Microorganisms § 173.135 Catalase derived from Micrococcus lysodeikticus. Bacterial catalase...



21 CFR 173.135 - Catalase derived from Micrococcus lysodeikticus.  

Code of Federal Regulations, 2010 CFR

...CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) SECONDARY DIRECT FOOD ADDITIVES PERMITTED IN FOOD FOR HUMAN CONSUMPTION Enzyme Preparations and Microorganisms § 173.135 Catalase derived from Micrococcus lysodeikticus. Bacterial catalase...



21 CFR 173.135 - Catalase derived from Micrococcus lysodeikticus.  

Code of Federal Regulations, 2011 CFR

...CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) SECONDARY DIRECT FOOD ADDITIVES PERMITTED IN FOOD FOR HUMAN CONSUMPTION Enzyme Preparations and Microorganisms § 173.135 Catalase derived from Micrococcus lysodeikticus. Bacterial catalase...




E-print Network

Page 1 HYDROGEN PEROXIDE INDUCED OXIDATION OF PEROXISOMAL MALATE SYNTHASE AND CATALASE. Pria Anand1-6100 E-mail: Short title: Oxidation of Peroxisomal Malate Synthase and Catalase * Revised Manuscript (Unmarked) Click here to view linked References #12;Page 2 Abbreviations CAT , catalase; MS

Simha, Rahul


Breaking of seed dormancy by catalase inhibition.  

PubMed Central

Germination of some dormant seeds is promoted by solutions of thiourea, sodium nitrite, and hydroxylamine salts. The promotions are accompanied by irreversible inhibition of catalase (EC in extracts from the seeds. The seeds are also promoted in germination by catechol and pyrogallol solutions. These effects are recorded for lettuce (Lactuca sativa L. cv. Grand Rapids) and pigweed (Amaranthus albus L.) seeds. The results indicae that metabolically derived hydrogen peroxide, spared from decomposition by catalase inhibition, oxidizes reduced NADPH required as the oxidant in the pentose pathway of glucose use. The metabolic system for such use of H2O2 involves the enzymes, peroxidase (EC and pyridine nucleotide quinone oxidoreductase (EC, which are present in the dormant seed prior to imbibition of water. PMID:235126

Hendricks, S B; Taylorson, R B



Gamma-irradiation-induced intercellular adhesion molecule-1 (ICAM-1) expression is associated with catalase: activation of Ap-1 and JNK.  


The ionizing radiation used in cancer therapy frequently produces damage to normal tissues and induces complex responses, including inflammation. The upregulation of the intercellular adhesion molecule-1 (ICAM-1) in response to numerous inducing factors is associated with inflammation. Therefore, this study examined the molecular mechanisms responsible for ICAM-1 expression induced by gamma-irradiation (gammaIR). ICAM-1 mRNA and cell surface expression were induced in A549 human lung epithelial cells after exposing them to gammaIR. Catalase expression and activity were also increased in gammaIR-treated cells. Treatment of the gammaIR-treated cells with catalase resulted in a significant increase in the ICAM-1 cell surface expression level. The catalase inhibitor 3-amino-1,2,4-triazole (AT) reduced the level of ICAM-1. Electrophoretic mobility shift assay (EMSA) analysis showed that activating protein 1 (AP-1) was activated by gammaIR, whereas NF-kappaB was not. Specific Jun N-terminal kinase (JNK) inhibition attenuated the upregulation of gammaIR stimulated ICAM-1. Western blot analysis revealed a marked elevation in activation of JNK. In addition, pretreatment with AT resulted in a decrease in the level of JNK phosphorylation and AP-1 activation. Overall, data suggest that induction of ICAM-1 expression by gammaIR is associated with catalase. Furthermore, catalase, JNKs, and AP-1 activation induce ICAM-1 upregulation through a sequential process. PMID:17062505

Son, Eun-Wha; Rhee, Dong-Kwon; Pyo, Suhkneung



Role of oxyradicals in the inactivation of catalase by ozone  

SciTech Connect

The antioxidant enzymes, catalase and superoxide dismutase, are inactivated upon exposure to ozone. In this study, the mechanism of this inactivation was examined using catalase as a model system. The data show that the inactivation of catalase is dependent on ozone concentration, time of exposure, and pH. Loss of catalase activity is accompanied with loss of the heme spectra. Tiron, desferal-Mn, trolox-c, and pyruvate protect the enzyme against ozone inactivation. SOD is less effective due to its inactivation by ozone. On the other hand, alcohols do not provide significant protection. The data suggest the possible involvement of superoxide radicals in the inactivation of catalase by ozone.

Whiteside, C.; Hassan, H.M. (North Carolina State Univ., Raleigh (USA))



Molecular Characterization of a Catalase from Hydra vulgaris  

PubMed Central

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

Dash, Bhagirathi; Phillips, Timothy D.



Inhibition of catalase activity in vitro by diesel exhaust particles  

SciTech Connect

The effect of diesel exhaust particles (DEP) on the activity of catalase, an intracellular anti-oxidant, was investigated because H{sub 2}O{sub 2} is a cytotoxic oxidant, and catalase released from alveolar cells is an important antioxidant in the epithelial lining fluid in the lung. DEP inhibited the activity of bovine liver catalase dose-dependently, to 25-30% of its original value. The inhibition of catalase by DEP was observed only in the presence of anions such as Cl{sup {minus}}, Br{sup {minus}}, or thiocyanate. Other anions, such as CH{sub 3}COO{sup {minus}} or SO{sub 4}{sup {minus}}, and cations such as K{sup +}, Na{sup +}, Mg{sup 2+}, or Fe{sup 2+}, did not affect the activity of catalase, even in the presence of DEP extract. Catalase from guinea pig alveolar cells and catalase from red blood cells were also inhibited by DEP extracts, as was catalase from bovine liver. These results suggest that DEP taken up in the lung and located on alveolar spaces might cause cell injury by inhibiting the activity of catalase in epithelial lining fluid, enhancing the toxicity of H{sub 2}O{sub 2} generated from cells in addition to that of O{sub 2}{sup {minus}} generated by the chemical reaction of DEP with oxygen. 10 refs., 6 figs.

Mori, Yoki; Murakami, Sumika; Sagae, Toshiyuki [Health Sciences Univ. of Hokkaido (Japan)] [and others] [Health Sciences Univ. of Hokkaido (Japan); and others



Catalase-positive microbial detection by using different ultrasonic parameters  

NASA Astrophysics Data System (ADS)

A method for rapid detection of catalase enzyme activity using ultrasonic parameters is presented in this work. It is based on the detection of the hydrolysis of hydrogen peroxide molecule into water and oxygen induced by the enzyme catalase. A special medium was made to amplify changes produced by catalase enzyme during the hydrolysis process. Enzymatic process can be monitored by means of ultrasonic parameters such as wave amplitude, time of flight (TOF), and backscattering measurements which are sensitive to oxygen bubble production. It is shown that catalase activity of the order of 10-3unit/ml can be detected using different ultrasonic parameters. The sensitivity provided by them is discussed.

Shukla, S. K.; Durán, C.; Elvira, L.



Upregulation of Opioid Receptors  

Microsoft Academic Search

\\u000a It is well established that chronic exposure to opioid receptor antagonists can result in opioid receptor upregulation. The\\u000a phenomenon of antagonist-induced receptor upregulation is not unique to the opioid system but is common to many receptor systems\\u000a including adenergic, cholinergic, serotinergic, and dopaminergic receptors. Chronic administration of naloxone or naltrexone\\u000a reliably produces increases in binding to opioid receptors both in

Ellen M. Unterwald; Richard D. Howells


Regulation of catalase enzyme activity by cell signaling molecules.  


Mitogenic cell proliferation requires a rapid and transient H2O2 generation, which is blocked by catalase or PKA activators. Previously, we observed that anemic HIV(+) individuals expressed acidic pIs of catalase in RBC with significantly high activities [Mol Cell Biochem 165: 77-81, 1996]. These findings led us to hypothesize that cell signaling molecules regulate catalase to control cell mitogenesis. To test the hypothesis, we determined (i) whether RBC counts correlate with their catalase activities, (ii) whether protein kinases and phosphatases alter catalase activity in vitro, and (iii) whether protein kinase activators increase catalase activity to suppress proliferation of cultured cells. The results indicated that RBC counts inversely correlated with RBC catalase activities in both HIV(+) (r: -0.6769, r2: 0.4582, n: 69 male, p < 0.0001) and HIV(-) (r: -0.3827, r2: 0.1464, n: 177 male, p < 0.0001) populations. Catalytic PKA, PKC and Casein Kinase II, but none of PKG, Ca2+/calmodulin kinase II and p34cdc/cyclinB, rapidly elevated catalase activity in vitro by up to 2-fold. Whereas a major CAT subunit (60 kDa) showed immunoreactive phosphoserine and phosphothreonine, the kinases- and gamma-32P-ATP-dependent phosphorylation occurred with a minor component (110 kDa). Among PKC isozymes examined, PKCzeta was the most effective modulator followed by PKCgamma, and protein phosphatase 1gamma and 2A decreased the catalase activity. PKA and PKCzeta activators of forskolin and okadaic acid increased catalase activity and 110 kDa expression in NIH3T3 cells up to 2.4-fold and suppressed the cell growth, showing an inverse correlation of the indices (r: -0.9286, r2: 0.8622, n: 18, p < 0.0001). Taken together, these results suggest for the first time that catalase is under the regulation of cell signaling molecules and capable of modulating mitogenic cell proliferation. PMID:12487379

Yano, Sumio; Yano, Noriko



Genes important for catalase activity in Enterococcus faecalis.  


Little in general is known about how heme proteins are assembled from their constituents in cells. The Gram-positive bacterium Enterococcus faecalis cannot synthesize heme and does not depend on it for growth. However, when supplied with heme in the growth medium the cells can synthesize two heme proteins; catalase (KatA) and cytochrome bd (CydAB). To identify novel factors important for catalase biogenesis libraries of E. faecalis gene insertion mutants were generated using two different types of transposons. The libraries of mutants were screened for clones deficient in catalase activity using a colony zymogram staining procedure. Analysis of obtained clones identified, in addition to katA (encoding the catalase enzyme protein), nine genes distributed over five different chromosomal loci. No factors with a dedicated essential role in catalase biogenesis or heme trafficking were revealed, but the results indicate the RNA degradosome (srmB, rnjA), an ABC-type oligopeptide transporter (oppBC), a two-component signal transducer (etaR), and NADH peroxidase (npr) as being important for expression of catalase activity in E. faecalis. It is demonstrated that catalase biogenesis in E. faecalis is independent of the CydABCD proteins and that a conserved proline residue in the N-terminal region of KatA is important for catalase assembly. PMID:22590595

Baureder, Michael; Hederstedt, Lars



Low Catalase Levels in the Epidermis of Patients with Vitiligo  

Microsoft Academic Search

Suction blister roofs taken from the involve and uninvolved epidermis of patients with vitiligo showed a consistent reduction in level of catalase compared to normal healthy controls of matched photo-skin types (Fitzpatrick classification). A decrease in catalase activity is expected to increase the concentration of hydrogen peroxide in the epidermis of these patients. Hydrogen peroxide function as a reversible inhibitor

Karin U. Schallreuter; John M. Wood; Jürgen Berger




Technology Transfer Automated Retrieval System (TEKTRAN)

Catalase activity was measured in various cob tissues during maize ear development because of its role in maintaining reactive oxygen homeostasis during biotic and abiotic stress. Catalase activity was determined in immature and mature embryos, pericarp, and rachis tissues of maize lines that are re...


Evidence against specific binding of salicylic acid to plant catalase  

Microsoft Academic Search

It was demonstrated that salicylic acid (SA) not only binds to catalase from differentiated higher plants and plant cell suspension cultures but also to those of fungi and animals. SA bound specifically to iron-containing enzymes, such as catalase, aconitase, lipoxidase and peroxidase, while not to iron-free plant enzymes. On the grounds of these experiments, the claim is further challenged that

Martina Rüffer; Boris Steipe; Meinhart H. Zenk



Catalase Deficiency Accelerates Diabetic Renal Injury Through Peroxisomal Dysfunction  

PubMed Central

Mitochondrial reactive oxygen species (ROS) play an important role in diabetes complications, including diabetic nephropathy (DN). Plasma free fatty acids (FFAs) as well as glucose are increased in diabetes, and peroxisomes and mitochondria participate in FFA oxidation in an interconnected fashion. Therefore, we investigated whether deficiency of catalase, a major peroxisomal antioxidant, accelerates DN through peroxisomal dysfunction and abnormal renal FFA metabolism. Diabetes was induced by multiple injections of low-dose streptozotocin into catalase knock-out (CKO) and wild-type (WT) C57BL/6 mice. Murine mesangial cells (MMCs) transfected with catalase small interfering RNA followed by catalase overexpression were used to further elucidate the role of endogenous catalase. Despite equivalent hyperglycemia, parameters of DN, along with markers of oxidative stress, were more accelerated in diabetic CKO mice than in diabetic WT mice up to 10 weeks of diabetes. CKO mice and MMCs showed impaired peroxisomal/mitochondrial biogenesis and FFA oxidation. Catalase deficiency increased mitochondrial ROS and fibronectin expression in response to FFAs, which were effectively restored by catalase overexpression or N-acetylcysteine. These data provide unprecedented evidence that FFA-induced peroxisomal dysfunction exacerbates DN and that endogenous catalase plays an important role in protecting the kidney from diabetic stress through maintaining peroxisomal and mitochondrial fitness. PMID:22315314

Hwang, Inah; Lee, Jiyoun; Huh, Joo Young; Park, Jehyun; Lee, Hi Bahl; Ho, Ye-Shih; Ha, Hunjoo



Catalases of bacteria isolated from thai fermented foods  

Microsoft Academic Search

Hydrogen peroxide production is found in 75% of L. plantarum, 73% L. pentosus, 93% Lactobacilli, 50% Pediococci and 38% Staphylococci (all were isolated from different Thai fermented foods). The heme dependent catalase activity is found in 70% of L. plantarum, 90% L. pentosus, all 3 strains of L. sake and all 11 strains of Pediococci and true catalase in all

P. Thiravattanamontri; S. Tanasupawat; W. Noonpakdee; R. Valyasevi



Investigating Catalase Activity Through Hydrogen Peroxide Decomposition by Bacteria Biofilms in Real Time Using Scanning  

E-print Network

Investigating Catalase Activity Through Hydrogen Peroxide Decomposition by Bacteria Biofilms University, Las Cruces, New Mexico 88003, United States *S Supporting Information ABSTRACT: Catalase activity electrochemical microscopy (SECM). The catalase activity, in units of micromoles hydrogen peroxide decomposed per

Nishiguchi, Michele


Contribution of catalase to hydrogen peroxide resistance in Enterococcus faecalis.  


Enterococcus faecalis exhibits high resistance to oxidative stress. Several enzymes are responsible for this trait. The role of alkyl hydroperoxide reductase (Ahp), thiol peroxidase (Tpx), and NADH peroxidase (Npr) in oxidative stress defense was recently characterized. Enterococcus faecalis, in contrast to many other streptococci, contains a catalase (KatA), but this enzyme can only be formed when the bacterium is supplied with heme. We have used this heme dependency of catalase activity and mutants deficient in KatA and Npr to investigate the role of the catalase in resistance against exogenous and endogenous hydrogen peroxide stress. The results demonstrate that in the presence of environmental heme catalase contributes to the protection against toxic effects of hydrogen peroxide. PMID:22486165

Baureder, Michael; Reimann, Ronny; Hederstedt, Lars



A Laboratory Experiment of the Purification of Catalase.  

ERIC Educational Resources Information Center

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)

Busquets, Montserrat; Franco, Rafael



Recent insights into microbial catalases: Isolation, production and purification.  


Catalase, an oxidoreductase enzyme, works as a detoxification system inside living cells against reactive oxygen species formed as a by-product of different metabolic reactions. The enzyme is found in a wide range of aerobic and anaerobic organisms. Catalase has also been employed in various analytical and diagnostic methods in the form of biosensors and biomarkers in addition to its other applications in textile, paper, food and pharmaceutical industries. New applications for catalases are constantly emerging thanks to their high turnover rate, distinct evolutionary origin, relatively simple and well-defined reaction mechanisms. The following review provides comprehensive information on isolation, production and purification of catalases with different techniques from various microbial sources along with their types, structure, mechanism of action and applications. PMID:25261851

Sooch, Balwinder Singh; Kauldhar, Baljinder Singh; Puri, Munish



SOD and catalase inactivation by singlet oxygen and peroxyl radicals  

Microsoft Academic Search

Both superoxide dismutase and catalase are readily deactivated by singlet oxygen and by the radicals produced in the pyrolysis of 2,2?-azo-bis-(2-amidinpropano) under aerobic conditions. The rate constant for the loss of enzymatic activity induced by singlet oxygen are 3.9 × 107 and 2.5 × 107 M?1 sec?1 for SOD and catalase, respectively. The similarity between these values implies that in

J. A. Escobar; M. A. Rubio; E. A. Lissi



Cytochemical discrimination between catalases and peroxidases using diaminobenzidine  

Microsoft Academic Search

The influence on diaminobenzidine staining of four variables: prefixation in aldehyde, temperature and pH of incubation, and H2O2 concentration, was investigated in catalase-, as well as in peroxydase-containing material. Catalase from five different sources and five types of peroxidase were examine. It is conclude: (a) when cells are incubated without prior fixation, in a DAB medium at room temperature and

Frank Roels; Eddie Wisse; Betty Prest; Jannes Meulen



The catalase activity of diiron adenine deaminase  

SciTech Connect

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.

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.



Identification of catalase-like activity from Mycobacterium leprae and the relationship between catalase and isonicotinic acid hydrazide (INH).  


As Mycobacterium leprae proliferate inside macrophages, it has been speculated that catalase encoded by katG may protect the bacilli from deleterious effects of peroxide generated from the macrophage and may also play a crucial role in the survival of M. leprae in vivo. However, unlike that of M. tuberculosis, the katG of M. leprae has been reported to be a pseudogene, implicating that isoniazid, which is activated to a potent tuberculocidal agent by catalase, is unlikely to be of therapeutic benefit to leprosy patients. These results raise a question as to how M. leprae avoids H202-mediated killing inside macrophages. To understand the survival of M. leprae in macrophages, the present study attempted to detect catalase-like activity in M. leprae. Catalase-like activity was found in M. leprae cell lysate by the diaminobenzidine (DAB) staining method with non-denaturing polyacrylamide gel electrophoresis. An ammonium sulphate precipitation study revealed that the catalase-like activity was precipitable with 80% ammonium sulphate. The effect of isoniazid (INH) on M. leprae growth was also tested by RT-PCR and radiorespirometric assay to examine catalase-like activity in M. leprae, because INH was activated by catalase. It was found that the viability of M. leprae was decreased at a concentration of 20 microg/ml by radiorespirometric assay and it was inhibited at higher concentrations as determined by RT-PCR. These data suggest that a catalase-like activity other than that encoded by katG is present in M. leprae. PMID:11478670

Kang, T J; You, J C; Chae, G T



Multiple periplasmic catalases in phytopathogenic strains of Pseudomonas syringae.  


Phytopathogenic strains of Pseudomonas syringae are exposed to plant-produced, detrimental levels of hydrogen peroxide during invasion and colonization of host plant tissue. When P. syringae strains were investigated for their capacity to resist H2O2, they were found to contain 10- to 100-fold-higher levels of total catalase activity than selected strains belonging to nonpathogenic related taxa (Pseudomonas fluorescens and Pseudomonas putida) or Escherichia coli. Multiple catalase activities were identified in both periplasmic and cytoplasmic fluids of exponential- and stationary-phase P. syringae cells. Two of these activities were unique to the periplasm of P. syringae pv. glycinea. During the stationary growth phase, the specific activity of cytoplasmic catalases increased four- to eightfold. The specific activities of catalases in both fluids from exponential-phase cells increased in response to treatment with 0.25 to 10 mM H2O2 but decreased when higher H2O2 concentrations were used. In stationary-growth phase cultures, the specific activities of cytoplasmic catalases increased remarkably after treatment with 0.25 to 50 mM H2O2. The growth of P. syringae into stationary phase and H2O2 treatment did not induce synthesis of additional catalase isozymes. Only the stationary-phase cultures of all of the P. syringae strains which we tested were capable of surviving high H2O2 stress at concentrations up to 50 mM. Our results are consistent with the involvement of multiple catalase isozymes in the reduction of oxidative stress during plant pathogenesis by these bacteria. PMID:1514792

Klotz, M G; Hutcheson, S W



Protandim attenuates intimal hyperplasia in human saphenous veins cultured ex vivo via a catalase-dependent pathway.  


Human saphenous veins (HSVs) are widely used for bypass grafts despite their relatively low long-term patency. To evaluate the role of reactive oxygen species (ROS) signaling in intima hyperplasia (IH), an early stage pathology of vein-graft disease, and to explore the potential therapeutic effects of up-regulating endogenous antioxidant enzymes, we studied segments of HSV cultured ex vivo in an established ex vivo model of HSV IH. Results showed that HSV cultured ex vivo exhibit an ~3-fold increase in proliferation and ~3.6-fold increase in intimal area relative to freshly isolated HSV. Treatment of HSV during culture with Protandim, a nutritional supplement known to activate Nrf2 and increase the expression of antioxidant enzymes in several in vitro and in vivo models, blocks IH and reduces cellular proliferation to that of freshly isolated HSV. Protandim treatment increased the activity of SOD, HO-1, and catalase 3-, 7-, and 12-fold, respectively, and decreased the levels of superoxide (O(2)(•-)) and the lipid peroxidation product 4-HNE. Blocking catalase activity by cotreating with 3-amino-1,2,4-triazole abrogated the protective effect of Protandim on IH and proliferation. In conclusion, these results suggest that ROS-sensitive signaling mediates the observed IH in cultured HSV and that up-regulation of endogenous antioxidant enzymes can have a protective effect. PMID:21167278

Joddar, Binata; Reen, Rashmeet K; Firstenberg, Michael S; Varadharaj, Saradhadevi; McCord, Joe M; Zweier, Jay L; Gooch, Keith J



Improving catalase-based propelled motor endurance by enzyme encapsulation.  


Biocatalytic propulsion is expected to play an important role in the future of micromotors as it might drastically increase the number of available fuelling reactions. However, most of the enzyme-propelled micromotors so far reported still rely on the degradation of peroxide by catalase, in spite of being vulnerable to relatively high peroxide concentrations. To overcome this limitation, herein we present a strategy to encapsulate the catalase and to graft the resulting enzyme capsules on motor particles. Significant improvement of the stability in the presence of peroxide and other aggressive agents has been observed. PMID:24964766

Simmchen, Juliane; Baeza, Alejandro; Ruiz-Molina, Daniel; Vallet-Regí, Maria



Determination of Catalase Activity at Physiological Hydrogen Peroxide Concentrations  

Microsoft Academic Search

A method for the determination of catalase activity (EC in homogenates and cell suspensions is described by following the decomposition of H2O2at physiological H2O2levels. This first chemiluminescence assay for catalase activity is based on the reaction of luminol (5-amino-2,3-dihydro-1,4-phthalazinedione) and NaOCl. The chemiluminescence of this reaction specifically depends on the H2O2concentration and shows fast kinetics of less than 2

Sebastian Mueller; Hans-Dieter Riedel; Wolfgang Stremmel



Improving catalase-based propelled motor endurance by enzyme encapsulation  

NASA Astrophysics Data System (ADS)

Biocatalytic propulsion is expected to play an important role in the future of micromotors as it might drastically increase the number of available fuelling reactions. However, most of the enzyme-propelled micromotors so far reported still rely on the degradation of peroxide by catalase, in spite of being vulnerable to relatively high peroxide concentrations. To overcome this limitation, herein we present a strategy to encapsulate the catalase and to graft the resulting enzyme capsules on motor particles. Significant improvement of the stability in the presence of peroxide and other aggressive agents has been observed.Biocatalytic propulsion is expected to play an important role in the future of micromotors as it might drastically increase the number of available fuelling reactions. However, most of the enzyme-propelled micromotors so far reported still rely on the degradation of peroxide by catalase, in spite of being vulnerable to relatively high peroxide concentrations. To overcome this limitation, herein we present a strategy to encapsulate the catalase and to graft the resulting enzyme capsules on motor particles. Significant improvement of the stability in the presence of peroxide and other aggressive agents has been observed. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr02459a

Simmchen, Juliane; Baeza, Alejandro; Ruiz-Molina, Daniel; Vallet-Regí, Maria



21 CFR 184.1034 - Catalase (bovine liver).  

Code of Federal Regulations, 2010 CFR

...CAS Reg. No. 81457-95-6) is an enzyme preparation obtained from extracts of...purified liquid or powder. Its characterizing enzyme activity is catalase (EC 1.11.1...requirements and additional requirements for enzyme preparations in the Food...



21 CFR 184.1034 - Catalase (bovine liver).  

Code of Federal Regulations, 2014 CFR

...CAS Reg. No. 81457-95-6) is an enzyme preparation obtained from extracts of...purified liquid or powder. Its characterizing enzyme activity is catalase (EC 1.11.1...requirements and additional requirements for enzyme preparations in the Food...



21 CFR 184.1034 - Catalase (bovine liver).  

Code of Federal Regulations, 2013 CFR

...CAS Reg. No. 81457-95-6) is an enzyme preparation obtained from extracts of...purified liquid or powder. Its characterizing enzyme activity is catalase (EC 1.11.1...requirements and additional requirements for enzyme preparations in the Food...



21 CFR 184.1034 - Catalase (bovine liver).  

Code of Federal Regulations, 2012 CFR

...CAS Reg. No. 81457-95-6) is an enzyme preparation obtained from extracts of...purified liquid or powder. Its characterizing enzyme activity is catalase (EC 1.11.1...requirements and additional requirements for enzyme preparations in the Food...



21 CFR 184.1034 - Catalase (bovine liver).  

Code of Federal Regulations, 2011 CFR

...CAS Reg. No. 81457-95-6) is an enzyme preparation obtained from extracts of...purified liquid or powder. Its characterizing enzyme activity is catalase (EC 1.11.1...requirements and additional requirements for enzyme preparations in the Food...



Plasma catalase activity and malondialdehyde level in patients with cataract  

Microsoft Academic Search

Purpose Oxidative mechanisms play a major role in the aetiology and pathogenesis of cataract, especially in age-related cataract. Our study aims to investigate systemic oxidant and antioxidant markers in cataract patients.Methods The activity of erythrocyte catalase and the level of malondialdehyde in plasma were measured in 40 patients with cataract and 60 healthy control subjects. The malondialdehyde level, as an

N A Ate?; Ö Yildirim; L Tamer; A Ünlü; B Ercan; N Mu?lu; A Kanik; R Hatungil; U Atik



A gasometric method to determine erythrocyte catalase activity  

Microsoft Academic Search

We describe a new gasometric method to determine erythrocyte catalase activity by the measurement of the volume of oxygen pro- duced 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

A. J. S. Siqueira; J. O. Remião; A. M. P. Azevedo; C. R. J. Azambuja



Catalase-peroxidases (KatG) exhibit NADH oxidase activity.  


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. PMID:15280362

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



Decreased Mitochondrial Hydrogen Peroxide Release in Transgenic Drosophila melanogaster Expressing Intramitochondrial Catalase  

Microsoft Academic Search

The objective of this study was to develop strategies for manipulating oxidative stress transgenically in a multicellular organism. Ectopic catalase was introduced into the mitochondrial matrix, which is the main intracellular site of H2O2 formation and where catalase is normally absent. Transgenic Drosophila melanogaster were generated by microinjection of a P element construct, containing the genomic catalase sequence of Drosophila,

Linda K. Kwong; Robin J. Mockett; Anne-Cécile V. Bayne; William C. Orr; Rajindar S. Sohal



Plant Physiol. (1978) 61, 957-960 Effects of Inhibitors of Catalase on Photosynthesis and on  

E-print Network

Plant Physiol. (1978) 61, 957-960 Effects of Inhibitors of Catalase on Photosynthesis and on Catalase Activity in Unwashed Preparations of Intact Chloroplasts Received for publication October 6, 1977] 3RA, United Kingdom ABSTRACT The catalase activity ofunwashed preparations containing intact spinach

Allen, John F.


Structure of the Heme d of Penicillium vitale and Escherichia coli Catalases*  

E-print Network

Structure of the Heme d of Penicillium vitale and Escherichia coli Catalases* (Received-hydroxychlorin -spirolactone has been found in the crystal structures of Penicillium vitale catalase and Escherichia coli catalase hydroperoxidase II (HPII). The absolute stereochemistry of the two heme d chiral car- bon atoms


Crystal Structure of Proteus mirabilisPR Catalase With and Without Bound NADPH  

Microsoft Academic Search

A catalase from a peroxide resistant mutant ofProteus mirabilisbinds NADPH tightly. Interestingly, this enzyme can be stripped of NADPH without loss of the catalatic activity. It is the only known non-mammalian catalase able to bind NADPH. The structure without cofactor was solved by molecular replacment using the structure of beef liver catalase as a model. The structure was refined to

Patrice Gouet; Hélène-Marie Jouve; Otto Dideberg



Purification and properties of recombinant rat catalase produced in Escherichia coli.  


Catalase is a characteristic enzyme of peroxisomes. To study the molecular mechanisms of the biogenesis of peroxisomes and catalase in a less complex system than rat liver cells, we expressed recombinant rat catalase in Escherichia coli, which has no peroxisomes. The concentration of recombinant catalase produced in E. coli transformed with the expression vector carrying the complete coding region of rat catalase cDNA was about 0.1% of the total soluble protein. The recombinant catalase was purified by DEAE-cellulose column chromatography followed by acidic ethanol precipitations. The properties of rat liver catalase and those of the recombinant were similar with respect to molecular mass, catalytic properties, profiles of absorption spectra, and iron contents. The NH2-terminal amino acid sequence of the purified recombinant catalase, as determined by Edman degradation, was in complete agreement with the amino acid sequence predicted from the nucleotide sequence of rat catalase cDNA, except that the first initiator methionine was not detected. The COOH-terminal amino acid sequence was determined by carboxypeptidase A digestion and the sequence, -Ala-Asn-Leu-OH, matched the predicted COOH-terminal amino acid sequence of rat catalase. Recombinant rat catalase gave almost the same multiple protein bands on native polyacrylamide gel isoelectric focusing as observed with authentic rat liver catalase. PMID:2204616

Furuta, S; Hayashi, H



The grid sectioning technique: a study of catalase platelets.  

PubMed Central

The grid sectioning technique has been used to obtain the two missing principal axis projections of orthorhombic catalase platelets and to measure directly the unit cell c-value. The negatively stained platelets have a unit cell c-dimension of half that proposed by Unwin (1975) from powder X-ray diffraction. The precision of the grid sectioning technique in positioning sections along a specimen axis shows that the growth fault lines usually observed on negatively stained catalase platelets are rows of missing molecules filled with stain. From these sections conclusions are drawn concerning the action of negative stain on a specimen, the microtomy process, and the specimen/supporting film interaction. Finally the value of microtomy for detailed structural analysis of biological objects is emphasized. Images Fig. 1. Fig. 2. Fig. 3. Fig. 4. Fig. 5. Fig. 6. Fig. 7. PMID:7188250

Jésior, J C



Induction of glucose oxidase, catalase, and lactonase in Aspergillus niger  

Microsoft Academic Search

The induction of glucose oxidase, catalase, and lactonase activities was studied both in wild-type and in glucose oxidase regulatory and structural mutants of Aspergillus niger. The structural gene for glucose oxidase was isolated and used for Northern analysis and in transformation experiments using various gox mutations. Wild-type phenotype could be restored in the glucose oxidase-negative mutant (goxC) by transformation with

Cor F. B. Witteveen; Hetty C. van den Broeck; Frank A. C. van Engelenburg; Leo H. de Graaff; Marcel H. B. C. Hillebrand; Peter J. Schaap; Jaap Visser



Dual targeting of yeast catalase A to peroxisomes and mitochondria.  

PubMed Central

Yeast catalase A (Cta1p) contains two peroxisomal targeting signals (SSNSKF) localized at its C-terminus and within the N-terminal third of the protein, which both can target foreign proteins to peroxisomes. In the present study we demonstrated that Cta1p can also enter mitochondria, although the enzyme lacks a classical mitochondrial import sequence. Cta1p co-targeting was studied in a catalase A null mutant after growth on different carbon sources, and expression of a Cta1p-GFP (green fluorescent protein)-fusion protein or a Cta1p derivative containing either a c-Myc epitope (Cta1p(myc)) or a SKF-extended tag (Cta1p(myc-SKF)). Peroxisomal and mitochondrial co-import of catalase A were tested qualitatively by fluorescence microscopy and functional complementation of a Delta cta1 null mutation, and quantitatively by subcellular fractionation followed by Western blot analysis and enzyme activity assays. Efficient Cta1p import into peroxisomes was observed when cells were cultivated under peroxisome-inducing conditions (i.e. growth on oleate), whereas significant co-import of Cta1p-GFP into mitochondria occurred when cells were grown under respiratory conditions that favour oxygen stress and ROS (reactive oxygen species) accumulation within this organelle. In particular, when cells were grown on the non-fermentable carbon source raffinose, respiration is maximally enhanced, and catalase A was efficiently targeted to the mitochondrial matrix where it presumably functions as scavenger of H2O2 and mitochondrial-derived ROS. PMID:14998369

Petrova, Ventsislava Y; Drescher, Diane; Kujumdzieva, Anna V; Schmitt, Manfred J



Chitosan microspheres as immobilized dye affinity support for catalase adsorption  

Microsoft Academic Search

Chitosan microsphere (CS) was prepared by phase-inversion method as the support matrices. Cibacron Blue F3GA (CB) was covalently attached to the chitosan microspheres, and thus the novel dye-affinity adsorbent was obtained. These Cibacron Blue F3GA-attached chitosan microspheres (CB-CS) were used in the catalase (CAT) adsorption studies. The maximum CAT adsorption capacity of Cibacron Blue F3GA-attached chitosan microspheres was 28.4mg\\/g at

Jingling Shentu; Jianmin Wu; Weihua Song; Zhishen Jia



Progeric effects of catalase inactivation in human cells.  


Peroxisomes generate hydrogen peroxide, a reactive oxygen species, as part of their normal metabolism. A number of pathological situations exist in which the organelle's capacity to degrade the potentially toxic oxidant is compromised. It is the peroxidase, catalase, which largely determines the functional antioxidant capacity of the organelle, and it is this enzyme that is affected in aging, in certain diseases, and in response to exposure to specific chemical agents. To more tightly control the enzymatic activity of peroxisomal catalase and carefully document the effects of its impaired action on human cells, we employed the inhibitor 3-amino-1,2,4-triazole. We show that by chronically reducing catalase activity to approximately 38% of normal, cells respond in a dramatic manner, displaying a cascade of accelerated aging reactions. Hydrogen peroxide and related reactive oxygen species are produced, protein and DNA are oxidatively damaged, import into peroxisomes and organelle biogenesis is corrupted, and matrix metalloproteinases are hyper-secreted from cells. In addition, mitochondria are functionally impaired, losing their ability to maintain a membrane potential and synthesize reactive oxygen species themselves. These latter results suggest an important redox-regulated connection between the two organelle systems, a topic of considerable interest for future study. PMID:18634817

Koepke, Jay I; Wood, Christopher S; Terlecky, Laura J; Walton, Paul A; Terlecky, Stanley R



Progeric effects of catalase inactivation in human cells  

SciTech Connect

Peroxisomes generate hydrogen peroxide, a reactive oxygen species, as part of their normal metabolism. A number of pathological situations exist in which the organelle's capacity to degrade the potentially toxic oxidant is compromised. It is the peroxidase, catalase, which largely determines the functional antioxidant capacity of the organelle, and it is this enzyme that is affected in aging, in certain diseases, and in response to exposure to specific chemical agents. To more tightly control the enzymatic activity of peroxisomal catalase and carefully document the effects of its impaired action on human cells, we employed the inhibitor 3-amino-1,2,4-triazole. We show that by chronically reducing catalase activity to approximately 38% of normal, cells respond in a dramatic manner, displaying a cascade of accelerated aging reactions. Hydrogen peroxide and related reactive oxygen species are produced, protein and DNA are oxidatively damaged, import into peroxisomes and organelle biogenesis is corrupted, and matrix metalloproteinases are hyper-secreted from cells. In addition, mitochondria are functionally impaired, losing their ability to maintain a membrane potential and synthesize reactive oxygen species themselves. These latter results suggest an important redox-regulated connection between the two organelle systems, a topic of considerable interest for future study.

Koepke, Jay I.; Wood, Christopher S.; Terlecky, Laura J. [Department of Pharmacology, Wayne State University School of Medicine, 540 E. Canfield Avenue, Detroit, Michigan, 48201 (United States); Walton, Paul A. [Department of Anatomy and Cell Biology, University of Western Ontario, London, Ontario (Canada); Terlecky, Stanley R. [Department of Pharmacology, Wayne State University School of Medicine, 540 E. Canfield Avenue, Detroit, Michigan, 48201 (United States)], E-mail:



cDNA cloning, characterization and expression analysis of catalase in swimming crab Portunus trituberculatus: cDNA cloning and expression analysis of catalase gene of Portunus trituberculatus.  


Catalase is an important antioxidant protein that protects organisms against various oxidative stresses by eliminating hydrogen peroxide. In the present study, a full-length cDNA sequence of catalase was cloned from the haemocytes of swimming crab Portunus trituberculatus by a reverse-transcription polymerase chain reaction (RT-PCR) and rapid amplification of cDNA end method. The catalase cDNA sequence contained 1,851 bp with an open reading frame of 1,551 bp encoding 516 amino acid residues. The conserved catalytic active residues His-71, Asn-144 and Tyr-354 were predicted in the amino acid sequence of P. trituberculatus catalase. The deduced catalase protein had a calculated molecular mass of 58.5 kDa with an estimated isoelectric point of 6.90. Multiple alignment analysis revealed that the deduced amino acid sequence of catalase shared high identity of 68-95 % with those of other species. Quantitative real-time RT-PCR analysis revealed that P. trituberculatus catalase transcript was strongly detected in haemocytes, hepatopancreas, heart, stomach, intestine, gill, ovary and muscle. The expression level of catalase transcripts both in haemocytes and hepatopancreas changed rapidly and dynamically after Vibrio alginolyticus challenging. These facts indicate that catalase was perhaps involved in the acute response against invading bacteria and was an inducible protein involved in the host innate immune response through elimination of H(2)O(2) in crab. PMID:23073768

Chen, Ping; Li, Jitao; Liu, Ping; Gao, Baoquan; Wang, Qingyin; Li, Jian



Are Catalase ?844A/G Polymorphism and Activity Associated with Childhood Obesity?  

PubMed Central

Abstract Catalase (CAT) is a peroxisomal antioxidant enzyme that is up-regulated upon oxidative stress. Previous studies have found associations between some single nucleotide polymorphisms (SNPs) located in the CAT promoter region in a variety of metabolic diseases. This is the first study that analyzes the association between erythrocyte CAT activity and candidate CAT SNPs with childhood obesity. The association study showed a significant positive association of the promoter variant ?844A/G with childhood obesity and biomarkers of obesity such as weight, body mass index (BMI), BMI Z-Score, and adipocyte fatty acid-binding protein, along with a tendency toward significance with insulin resistance biomarkers. In addition, CAT erythrocyte activity was found to be significantly lower in obese children, and it was significantly correlated with obesity and insulin resistance biomarkers. No association was found between erythrocyte CAT activity and the SNP ?844A/G. However, further in vitro and in vivo studies are needed to fully understand the role of CAT activity and SNPs in the development of insulin resistance in the setting of obesity. We hypothesize that CAT plays a role in early metabolic complications of obesity. Antioxid. Redox Signal. 19, 1970–1975. PMID:23641975

Rupérez, Azahara I.; Olza, Josune; Gil-Campos, Mercedes; Leis, Rosaura; Mesa, María D.; Tojo, Rafael; Cañete, Ramón; Gil, Ángel



Plating isolation of various catalase-negative microorganisms from soil  

NASA Technical Reports Server (NTRS)

A unique plating procedure was developed that allows isolation, but not enumeration, of representatives of the catalase-negative soil microflora. The numbers recovered, however, are low as compared to the numbers recovered when the modified dilution-to-extinction isolation procedure is used. The latter procedure provides prolonged inoculation in sealed tubes containing a nutritionally rich broth medium over small submerged agar slants. In contrast, the plating procedure utilizes nutritionally minimal media and the shorter incubations mandated by the inherent problems associated with plating.

Labeda, D. P.; Hunt, C. M.; Casida, L. E., Jr.



Restoration of peroxisomal catalase import in a model of human cellular aging.  


Peroxisomes play an important role in human cellular metabolism by housing enzymes involved in a number of essential biochemical pathways. Many of these enzymes are oxidases that transfer hydrogen atoms to molecular oxygen forming hydrogen peroxide. The organelle also contains catalase, which readily decomposes the hydrogen peroxide, a potentially damaging oxidant. Previous work has demonstrated that aging compromises peroxisomal protein import with catalase being particularly affected. The resultant imbalance in the relative ratio of oxidases to catalase was seen as a potential contributor to cellular oxidative stress and aging. Here we report that altering the peroxisomal targeting signal of catalase to the more effective serine-lysine-leucine (SKL) sequence results in a catalase molecule that more strongly interacts with its receptor and is more efficiently imported in both in vitro and in vivo assays. Furthermore, catalase-SKL monomers expressed in cells interact with endogenous catalase subunits resulting in altered trafficking of the latter molecules. A dramatic reduction in cellular hydrogen peroxide levels accompanies this increased peroxisomal import of catalase. Finally, we show that catalase-SKL stably expressed in cells by retroviral-mediated transduction repolarizes mitochondria and reduces the number of senescent cells in a population. These results demonstrate the utility of a catalase-SKL therapy for the restoration of a normal oxidative state in aging cells. PMID:17822396

Koepke, Jay I; Nakrieko, Kerry-Ann; Wood, Christopher S; Boucher, Krissy K; Terlecky, Laura J; Walton, Paul A; Terlecky, Stanley R



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

PubMed Central

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. PMID:25045672

Fu, Xinhua; Wang, Wei; Hao, Jianhua; Zhu, Xianglin; Sun, Mi



Dierential developmental expression and cell type specicity of Dictyostelium catalases and their response to oxidative stress and  

E-print Network

Di¡erential developmental expression and cell type speci¢city of Dictyostelium catalases the Dictyostelium catalase and Cu/Zn superoxide dismutase antioxidant enzymes. We show that there are two catalase oxidative damage. We found that exposure to H2O2 does not result in the induction of the catalase

Devreotes, Peter


Peroxisomal catalase deficiency modulates yeast lifespan depending on growth conditions.  


We studied the role of peroxisomal catalase in chronological aging of the yeastHansenula 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 that are not oxidized by peroxisomal enzymes. However, when media contained methylamine, which is oxidized by peroxisomal amine oxidase, the CLS of cat cells was significantly reduced. Conversely, the CLS of cat cells was enhanced relative to the wild-type control, when cells were grown on methanol, which is oxidized by peroxisomal alcohol oxidase. At these conditions strongly enhanced ROS levels were observed during the exponential growth phase of cat cells. This was paralleled by activation of the transcription factor Yap1, as well as an increase in the levels of the antioxidant enzymes cytochrome c peroxidase and superoxide dismutase. Upon deletion of the genes encoding Yap1 or cytochrome c peroxidase, the CLS extension of cat cells on methanol was abolished. These findings reveal for the first time an important role of enhanced cytochrome c peroxidase levels in yeast CLS extension. PMID:23425686

Kawa?ek, Adam; Lefevre, Sophie D; Veenhuis, Marten; van der Klei, Ida J



High Conformational Stability of Secreted Eukaryotic Catalase-peroxidases  

PubMed Central

Catalase-peroxidases (KatGs) are bifunctional heme enzymes widely spread in archaea, bacteria, and lower eukaryotes. Here we present the first crystal structure (1.55 Å resolution) of an eukaryotic KatG, the extracellular or secreted enzyme from the phytopathogenic fungus Magnaporthe grisea. The heme cavity of the homodimeric enzyme is similar to prokaryotic KatGs including the unique distal +Met-Tyr-Trp adduct (where the Trp is further modified by peroxidation) and its associated mobile arginine. The structure also revealed several conspicuous peculiarities that are fully conserved in all secreted eukaryotic KatGs. Peculiarities include the wrapping at the dimer interface of the N-terminal elongations from the two subunits and cysteine residues that cross-link the two subunits. Differential scanning calorimetry and temperature- and urea-mediated unfolding followed by UV-visible, circular dichroism, and fluorescence spectroscopy combined with site-directed mutagenesis demonstrated that secreted eukaryotic KatGs have a significantly higher conformational stability as well as a different unfolding pattern when compared with intracellular eukaryotic and prokaryotic catalase-peroxidases. We discuss these properties with respect to the structure as well as the postulated roles of this metalloenzyme in host-pathogen interactions. PMID:22822072

Zámocký, Marcel; García-Fernández, Queralt; Gasselhuber, Bernhard; Jakopitsch, Christa; Furtmüller, Paul G.; Loewen, Peter C.; Fita, Ignacio; Obinger, Christian; Carpena, Xavi



Comperative study of catalase immobilization on chitosan, magnetic chitosan and chitosan-clay composite beads.  


Catalase was immobilized on chitosan and modified chitosan. Studies were carried out on free-immobilized catalase concerning the determination of optimum temperature, pH, thermal, storage stability, reusability, and kinetic parameters. Optimum temperature and pH for free catalase and catalase immobilized were found as 35°C and 7.0, respectively. After 100 times of repeated tests, the immobilized catalases on chitosan-clay and magnetic chitosan maintain over 50% and 60% of the original activity, respectively. The ease of catalase immobilization on low-cost matrices and good stability upon immobilization in the present study make it a suitable product for further use in the food industry. PMID:23687952

Ba?ak, Esra; Aydemir, Tülin; Dinçer, Ay?e; Becerik, Seda Ç?nar



Fluorescence Spectrometry of the Interaction of Multi-Walled Carbon Nanotubes with Catalase  

NASA Astrophysics Data System (ADS)

The interaction of multi-walled carbon nanotubes (MWCNTs) with catalase is investigated using fluorescence and circular dichroism spectroscopic techniques. The results of the fluorescence experiments suggest that MWCNTs quench the intrinsic fluorescence of catalase via a static quenching mechanism. The circular dichroism spectral results reveal the unfolding of catalase with a significant decrease in the ?-helix content in the presence of MWCNTs, which indicates that the conformation of catalase is changed in the binding process, thereby remarkably decreasing its activity. The binding constants and the number of binding sites of the MWCNT to the catalase are calculated at different temperatures. The thermodynamic parameters, such as the changes in free energy (?G), enthalpy (?H), and entropy (?S), are calculated using thermodynamic equations. The fact that all negative values of ?G, ?H, and ?S are obtained suggests that the interaction of the MWCNTs with catalase is spontaneous, and that hydrogen bonding and van der Waals interactions play an important role in the binding process.

Fan, Y.; Li, Y.; Cai, H.; Li, J.; Miao, J.; Fu, D.; Yang, Q.



A bioinspired polymer-bound Mn-porphyrin as an artificial active center of catalase.  


The complex comprising a cationic Mn-porphyrin and carboxymethyl poly(1-vinylimidazole) (CM-PVIm) was prepared as an artificial active center of catalase. Interestingly, the catalase activity of the complex depends on the chain length of the polymer and the chemical structure of Mn-porphyrin. This study is one step forward in the development of a new class of water-soluble catalase mimics. PMID:25380330

Kubota, Riku; Asayama, Shoichiro; Kawakami, Hiroyoshi



Determination of the activity of catalase using a europium(III)–tetracycline-derived fluorescent substrate  

Microsoft Academic Search

A one-step method is described for the fluorometric determination of the activity of the enzyme catalase (EC, based on the finding that H2O2 in the europium (III)–tetracycline–hydrogen peroxide system is consumed by catalase. This is accompanied by a large decrease in both fluorescence intensity and decay time. The limit of detection (LOD; at S\\/N=3) for catalase at 30°C for

Meng Wu; Zhihong Lin; Otto S. Wolfbeis



Methods for Determining the Rates of Catalase Synthesis and Destruction in vivo  

Microsoft Academic Search

ALTERATIONS in the amount of enzyme in a tissue can result from changes in the rate of synthesis or of destruction. The demonstration that 3-amino-1,2,4-triazole irreversibly inactivates catalase in the liver1 without interfering with its resynthesis2, and allyl-isopropyl acetamide blocks synthesis of new catalase3 suggested that these compounds might be used as tools for studying the kinetics of catalase synthesis

V. E. Price; M. Rechcigl; R. W. Hartley



Temporal Variation for the Expression of Catalase in DROSOPHILA MELANOGASTER: Correlations between Rates of Enzyme Synthesis and Levels of Translatable Catalase-Messenger RNA  

PubMed Central

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. PMID:3091448

Bewley, Glenn C.; Mackay, William J.; Cook, Julia L.



Catalase binds Grb2 in tumor cells when stimulated with serum or ligands for integrin receptors.  


Recent studies have demonstrated that H(2)O(2) acts as a second messenger of mitogenic signaling and that catalase is under the regulation of PKA and PKC signaling. Here we examined whether catalase binds any mitogenic signaling molecules. Our results indicated that serum stimulation of HeLa, Caco-2, and LiSa-2 cells, but not BJ-1 and primary human bronchial epithelial cells, resulted in catalase binding to Grb2. Whereas serum deprivation, butyrate, and herbimycin-A negatively regulated the binding, an extended culture of confluent Caco-2 cells resulted in binding of an additional but as yet unidentified molecule to the Grb2-catalase complex. Expression of active catalase nearly 15-fold over control level in Tet-off HeLa cells substantially increased binding to Grb2, and this was sensitive to 3-aminotriazole, a specific catalase inhibitor. Furthermore, fibrinogen, fibronectin, and laminin, but not collagen types I to V, hyaluronic acid, elastin, insulin, EGF, IGF-I, PDGF, or NGF, resulted in binding similar to that of serum. A mutation of tyrosine to phenylalanine at 447 abolished the binding capability of catalase to Grb2 in vitro. These results support the view that catalase (447)Tyr-Val-Asn-Val binds Grb2 upon phosphorylation in tumor cells when stimulated with serum or ligands for integrin receptors. This is the first report demonstrating that catalase binds a SH2 domain of the molecule and participates in integrin signaling. PMID:15182856

Yano, Sumio; Arroyo, Nelly; Yano, Noriko



Bacterial Catalase in the Microsporidian Nosema locustae: Implications for Microsporidian Metabolism and Genome Evolution  

PubMed Central

Microsporidia constitute a group of extremely specialized intracellular parasites that infect virtually all animals. They are highly derived, reduced fungi that lack several features typical of other eukaryotes, including canonical mitochondria, flagella, and peroxisomes. Consistent with the absence of peroxisomes in microsporidia, the recently completed genome of the microsporidian Encephalitozoon cuniculi lacks a gene for catalase, the major enzymatic marker for the organelle. We show, however, that the genome of the microsporidian Nosema locustae, in contrast to that of E. cuniculi, encodes a group II large-subunit catalase. Surprisingly, phylogenetic analyses indicate that the N. locustae catalase is not specifically related to fungal homologs, as one would expect, but is instead closely related to proteobacterial sequences. This finding indicates that the N. locustae catalase is derived by lateral gene transfer from a bacterium. The catalase gene is adjacent to a large region of the genome that appears to be far less compact than is typical of microsporidian genomes, a characteristic which may make this region more amenable to the insertion of foreign genes. The N. locustae catalase gene is expressed in spores, and the protein is detectable by Western blotting. This type of catalase is a particularly robust enzyme that has been shown to function in dormant cells, indicating that the N. locustae catalase may play some functional role in the spore. There is no evidence that the N. locustae catalase functions in a cryptic peroxisome. PMID:14555490

Fast, Naomi M.; Law, Joyce S.; Williams, Bryony A. P.; Keeling, Patrick J.



Effect of a gas environment on catalase cryolysis  

NASA Technical Reports Server (NTRS)

Catalase is inactivated during repeated freezing and thawing of its solutions. The effect depends on the temperature of freezing and the gas atmosphere. Gases tested for the degree of their effect on cryolysis in order of increasing effect on inactivation of the enzymes are: N2, He, O2, and H2. In a gas environment consisting of oxygen and nitrogen an additive summation of the effects on cryolysis which were produced by each gas separately is observed. The effect of an atmosphere consisting of hydrogen and argon and cryolysis of an enzyme revealed a significant increase of inactivation in comparison to the expected motivation for the case of additive summation of effects produced by each gas separately.

Komolova, G. S.



Compounds I of Catalase and Horse Radish Peroxidase: ?-Cation Radicals  

PubMed Central

Two-electron oxidation of cobaltous octaethylporphyrin [Co(II)(Et)8P] yields a stable ?-cation radical [Co(III)(Et)8P]2+., the optical spectrum of which exhibits spectral changes dependent upon the nature of the counterion. Comparison of these spectra with those of Compounds I of horseradish peroxidase and catalase leads us to propose that these Compounds I contain a ?-cation radical of the heme prosthetic group. This proposal explains the oxidation level, optical spectra, and stability of the primary compounds without recourse to properties such as stoichiometric mixtures of special porphyrins, stable Fe(V) porphyrins, or unique conformers of heme porphyrins. Explanations are advanced to account for the missing electron spin resonance signal of Compound I of horseradish peroxidase. PMID:5276770

Dolphin, D.; Forman, A.; Borg, D. C.; Fajer, J.; Felton, R. H.



Catalase and estradiol inhibit mitochondrial protein S-glutathionylation.  


Regulation and downstream effects of mitochondrial protein S-glutathionylation in response to oxidative stress are poorly understood. The study aim was to determine whether anti-oxidants such as catalase and estradiol alter mitochondrial protein S-glutathionylation and in turn affect apoptosis following ultraviolet B (UV-B) light irradiation. HeLa cells were transduced with increasing amounts of adenovirus encoding catalase (Ad-Cat) and ?-galactosidase (Ad-Lac Z) or pre-incubated with estradiol before induction of apoptosis by UV-B light exposure. Inhibition of mitochondrial protein S-glutathionylation was assessed using autoantibodies specific for the non-S-glutathionylated form of PDC-E2. The percentage of apoptotic cells following UV-B irradiation were not significantly different between mock cells (cells with no virus infection) and Ad-Cat and Ad-Lac Z infected cells at all viral doses (all p > 0.050). Autoantibody staining of non-S-glutathionylated PDC-E2 in apoptotic cells was three times greater in only Ad-Cat infected cells compared to only Ad-Lac Z infected cells (81.3 ± 16.7 vs 26 ± 7.2 %, respectively, p = 0.030). Similarly estradiol treatment (33 and 100 nM) also significantly increased PDC-E2 staining in apoptotic cells compared to non-treated cells (both p < 0.010). The percentage of apoptotic cells was not significantly different with any of the estradiol concentrations (all p > 0.100). The observed procaspase 12 cleavage following UV-B irradiation suggests that a mitochondrial-independent apoptotic pathway was activated. In conclusion, following an apoptotic stimulus, estradiol may inhibit mitochondrial protein S-glutathionylation without inhibiting apoptosis. This effect may play a role in ninefold greater prevalence of autoantibodies against PDC-E2 in women with primary biliary cirrhosis. PMID:22661379

Hu, Bin; Allina, Jorge; Bai, Jingxiang; Kesar, Vivek; Odin, Joseph A



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

PubMed Central

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 ?M). 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 ?M). 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

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



Regulation of catalase activity in leaves of Nicotiana sylvestris by high CO sub 2  

SciTech Connect

The effect of high CO{sub 2} (1% CO{sub 2}/21% O{sub 2}) on the activity of specific forms of catalase (CAT-1, -2, and -3) in seedling leaves of tobacco (Nicotiana sylvestris, Nicotiana tabacum) was examined. In high CO{sub 2} total catalase activity decreased by 50% in the first 2 days, followed by a more gradual decline in the next 4 days. The loss of total activity resulted primarily from a decrease in CAT-1 catalase. In contrast, the activity of CAT-3 catalase, a form with enhanced peroxidatic activity, increased 3-fold in high CO{sub 2} relative to air controls after 4 days. Short-term exposure to high CO{sub 2} indicated that the 50% loss of total activity occurs in the firs 12 hours. Catalase levels increased to normal within 12 hours after seedlings were returned to air. When seedlings were transferred to air after prolonged exposure to high CO{sub 2} (13 days), the levels of CAT-1 catalase were partially restored while CAT-3 remained at its elevated level. Levels of superoxide dismutase activity and those of several peroxisomal enzymes were not affected by high CO{sub 2}. Total catalase levels did not decline when seedlings were exposed to atmospheres of 0.04% CO{sub 2}/5% O{sub 2} or 0.04% CO{sub 2}/1% O{sub 2}, indicating that regulation of catalase in high CO{sub 2} is not related directly to suppression of photorespiration. Antibodies prepared against CAT-1 catalase from N. tabacum reacted strongly against CAT-1 catalase from both N. sylvestris and N. tabacum but not against CAT-3 catalase from either species.

Havir, E.A.; McHale, N.A. (Connecticut Agricultural Experiment Station, New Haven (USA))



Neural upregulation in interstitial cystitis.  


Interstitial cystitis (IC) is a syndrome of bladder hypersensitivity with symptoms of urgency, frequency, and chronic pelvic pain. Although no consensus has been reached on the underlying cause of IC, several pathophysiologic mechanisms, including epithelial dysfunction, mast cell activation, and neurogenic inflammation, have been proposed. Despite multiple different causes of urinary cystitis, the bladder's response to cystitis is limited and typical. Animal experiments have shown upregulation of proteinase-activated receptors, tryptase, beta-nerve growth factor, inducible nitric oxide synthase, nuclear transcription factor-kappaB, c-Fos, phosphodiesterase 1C, cyclic adenosine monophosphate (cAMP)-dependent protein kinase, and proenkephalin B. After the noxious stimulus has abated, downregulation of genes appears to follow. Distention of the bladder results in the release of adenosine triphosphate (ATP) from urothelial cells, which activates purinergic P2X3 receptors. Activation by ATP of P2X3-expressing afferents is a fundamental signaling factor in bladder sensation and appears to play a role in bladder reflexes. Fos proteins present in spinal cord neurons have been shown to be upregulated in animals that have undergone cyclophosphamide-induced chemical cystitis. These and other findings suggest that neural upregulation occurs both peripherally and centrally in subjects with chronic cystitis. It is unclear whether neural mechanisms and inflammation are the cause of IC or the result of other initiating events. Neural upregulation is known to play a role in the chronicity of pain, urgency, and frequency and represents an exciting area of research that may lead to additional treatments and a better understanding of IC. PMID:17462476

Nazif, Omar; Teichman, Joel M H; Gebhart, G F




E-print Network

BIOLOGY OF HONEYBEE SPERMATOZOA. 3. EFFECT OF AMINO ACIDS AND CATALASE ON RESPIRATION AS MEASURED.R.G. SUMMARY The addition of exogenous amino acids such as L-lysine, L-arginine, L-glutamic acid and enzyme the earlier view that these amino acids and catalase has beneficial effect on motility and survival

Paris-Sud XI, Université de



Microsoft Academic Search

Beef liver catalase was injected intravenously into mice, and its distribution in the kidney, myocardium, and liver was studied with the electron microscope .A specific and relatively sensitive method was developed for its ultrastructural localization, based on the peroxidatic activity of catalase and employing a modified Graham and Karnovsky incubation medium. The main features of the medium were a higher




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

PubMed Central

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 ?-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

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



Catalase deciency drastically affects gene expression induced by high light in Arabidopsis thaliana  

E-print Network

concentrations. Reduced peroxisomal cata- lase activity increased sensitivity toward both ozone counteracted by peroxisomal catalase, although other antioxidative enzymes are active in the leaf peroxi- some (Corpas et al., 2001). Catalase is a tetrameric iron porphyrin that catalyzes the dismutation of H2O2

Gent, Universiteit


Development of a catalase based biosensor for alcohol determination in beer samples  

Microsoft Academic Search

An amperometric biosensor based on catalase enzyme for alcohol determination was developed. To construct the biosensor catalase was immobilized by using gelatin and glutaraldehyde on a Clark type dissolved oxygen (DO) probe covered with a teflon membrane which is sensitive for oxygen. The working principle of the biosensor depends on two reactions, which one is related to another, catalyzed by

Erol Akyilmaz; Erhan Dinçkaya



Measurement of superoxide dismutase, catalase and glutathione peroxidase in cultured cells and tissue  

Microsoft Academic Search

Cells contain a large number of antioxidants to prevent or repair the damage caused by reactive oxygen species, as well as to regulate redox-sensitive signaling pathways. General protocols are described to measure the antioxidant enzyme activity of superoxide dismutase (SOD), catalase and glutathione peroxidase. The SODs convert superoxide radical into hydrogen peroxide and molecular oxygen, whereas the catalase and peroxidases

Christine J Weydert; Joseph J Cullen



Calcium Effects on Superoxide Dismutase and Catalase of the Rabbit Urinary Bladder Muscle and Mucosa  

Microsoft Academic Search

Purpose: Superoxide dismutase (SOD) and catalase are two important antioxidant mechanisms that work together to reduce free radical damage. Intracellular free calcium in smooth muscle can change rapidly and many enzymes can be affected. The sensitivity of SOD and catalase activity to calcium was determined in both rabbit bladder smooth muscle and mucosa. Materials and Methods: Calcium sensitivity was analyzed

Brittany Fitzpatrick; Catherine Schuler; Robert E. Leggett; Robert M. Levin



Spectrophotometric determination of hydrogen peroxide: catalase activity and rates of hydrogen peroxide removal by erythrocytes  

Microsoft Academic Search

A new method of hydrogen peroxide determination for the measurement of catalase activity and rates of hydrogen peroxide removal by erythrocytes was described. Hydrogen peroxide was determined by converting it to the indamine dye with a water-soluble ironporphyrin and measuring the absorbance at 590 nm. This method was applied to the assay of catalase in hemolysates from human, rat and

Noriyoshi Masuoka; Masahiro Wakimoto; Toshihiko Ubuka; Taku Nakano



The relevance of the non-canonical PTS1 of peroxisomal catalase.  


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, but invariably is sorted to peroxisomes via a non-canonical sorting sequence. We analyzed the relevance of the non-canonical PTS1 of catalase of the yeast Hansenula polymorpha (-SKI). Using isothermal titration microcalorimetry, we show that the affinity of H. polymorpha Pex5 for a peptide containing -SKI at the C-terminus is 8-fold lower relative to a peptide that has a C-terminal -SKL. Fluorescence microscopy indicated that green fluorescent protein containing the -SKI tripeptide (GFP-SKI) has a prolonged residence time in the cytosol compared to GFP containing -SKL. Replacing the -SKI sequence of catalase into -SKL resulted in reduced levels of enzymatically active catalase in whole cell lysates together with the occurrence of catalase protein aggregates in the peroxisomal matrix. Moreover, the cultures showed a reduced growth yield in methanol-limited chemostats. Finally, we show that a mutant catalase variant that is unable to properly fold mislocalizes in protein aggregates in the cytosol. However, by replacing the PTS1 into -SKL the mutant variant accumulates in protein aggregates inside peroxisomes. Based on our findings we propose that the relatively weak PTS1 of catalase is important to allow proper folding of the enzyme prior to import into peroxisomes, thereby preventing the accumulation of catalase protein aggregates in the organelle matrix. PMID:22546606

Williams, Chris; Bener Aksam, Eda; Gunkel, Katja; Veenhuis, Marten; van der Klei, Ida J



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


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. PMID:24331417

Afiyanti, Mufidah; Chen, Hsien-Jung



A Review on Direct Electrochemistry of Catalase for Electrochemical Sensors  

PubMed Central

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. PMID:22573989

Prakash, Periasamy Arun; Yogeswaran, Umasankar; Chen, Shen-Ming



Loss of catalase activity in Tn1545-induced mutants does not reduce growth of Listeria monocytogenes in vivo.  

PubMed Central

Two catalase-negative mutants of Listeria monocytogenes were obtained by chromosomal insertions of the conjugative transposon Tn1545. The loss of catalase activity did not reduce the level of virulence of these mutants in mice. Indeed, both mutants were capable of growing in host tissues at the same rate as the parental catalase-positive strain. These results favor the view that catalase does not play a critical role in the resistance of L. monocytogenes to macrophage killing. PMID:2545629

Leblond-Francillard, M; Gaillard, J L; Berche, P



Characterization of a manganese-containing catalase from the obligate thermophile Thermoleophilum album.  

PubMed Central

A manganese-containing catalase has been characterized from Thermoleophilum album NM, a gram-negative aerobic bacterium obligate for thermophily and n-alkane substrates. The level of catalase in cells was increased about ninefold by growth in the presence of paraquat (2.5 microM), a superoxide-generating toxicant. Superoxide dismutase levels were unaffected by this compound. The enzyme was purified from cultures grown in the presence of paraquat to greater than 95% homogeneity and had an Mr of 141,000. The enzyme was composed of four subunits, and each had an Mr of 34,000. There were 1.4 +/- 0.4 atoms of manganese present per subunit. The catalase had a Km for hydrogen peroxide of 15 mM and a Vmax of 11 mM/mg. Peroxidase activity, as measured with p-phenylenediamine, copurified with the catalase. Inhibitors of heme-catalase were weak inhibitors of the T. album enzyme. The optimum pH for catalase activity was 8 to 9. The enzyme was stable from pH 6.5 to 11 and retained activity at assay temperatures from 25 to 80 degrees C. The catalase was stable for 24 h of incubation at 60 degrees C. PMID:3782016

Allgood, G S; Perry, J J



Catalase characterization and implication in bleaching of a symbiotic sea anemone.  


Symbiotic cnidarians are marine invertebrates harboring photosynthesizing microalgae (named zooxanthellae), which produce great amounts of oxygen and free radicals upon illumination. Studying antioxidative balance is then crucial to understanding how symbiotic cnidarians cope with ROS production. In particular, it is suspected that oxidative stress triggers cnidarian bleaching, i.e., the expulsion of zooxanthellae from the animal host, responsible for symbiotic cnidarian mass mortality worldwide. This study therefore investigates catalase antioxidant enzymes and their role in bleaching of the temperate symbiotic sea anemone Anemonia viridis. Using specific separation of animal tissues (ectoderm and endoderm) from the symbionts (zooxanthellae), spectrophotometric assays and native PAGE revealed both tissue-specific and activity pattern distribution of two catalase electrophoretypes, E1 and E2. E1, expressed in all three tissues, presents high sensitivity to the catalase inhibitor aminotriazole (ATZ) and elevated temperatures. The ectodermal E1 form is responsible for 67% of total catalase activity. The E2 form, expressed only within zooxanthellae and their host endodermal cells, displays low sensitivity to ATZ and relative thermostability. We further cloned an ectodermal catalase, which shares 68% identity with mammalian monofunctional catalases. Last, 6 days of exposure of whole sea anemones to ATZ (0.5 mM) led to effective catalase inhibition and initiated symbiont expulsion. This demonstrates the crucial role of this enzyme in cnidarian bleaching, a phenomenon responsible for worldwide climate-change-induced mass mortalities, with catastrophic consequences for marine biodiversity. PMID:17189829

Merle, Pierre-Laurent; Sabourault, Cécile; Richier, Sophie; Allemand, Denis; Furla, Paola



Post-irradiation modification of oxygen-dependent and independent damage by catalase in barley seeds.  


If H2O2 is one of the major mediators of the 'oxygen effect' in biological systems then catalase, which enzymically decomposes H2O2 should have a significant influence on radiation damage, particularly under oxygenated conditions. The post-irradiation (300 Gy gamma rays) effect of catalase was, therefore, assessed on barley seeds of about 4 per cent moisture content under oxygenated and oxygen-free conditions at varying temperatures. Catalase affords concentration-dependent radioprotection under oxygenated condition at both 25 degrees C and 4 degrees C. The level of protection at 4 degrees C is less than at 25 degrees C. This is obviously due to a decrease in catalase activity at low temperature. Under oxygen-free conditions, catalase enhances radiation damage at 4 degrees C while at 25 degrees C it has no effect. This has been substantiated by data on the frequency of chromosomal aberrations and on peroxidase activity. Sodium azide, a catalase inhibitor, was found to eliminate the radioprotective action of catalase. The study supports the view that the 'oxygen effect' is mediated largely through peroxides in irradiated biological systems. However, the observations made particularly at 4 degrees C under oxygen-free condition seem to involve physicochemical reactions. PMID:3495510

Sah, N K; Kesavan, P C



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

SciTech Connect

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.

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)] [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)] [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)] [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)] [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)] [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)] [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)] [Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chunchon 200-702 (Korea, Republic of); Hwang, Hyun Sook, E-mail: [Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chunchon 200-702 (Korea, Republic of); Choi, Soo Young, E-mail: [Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chunchon 200-702 (Korea, Republic of)




E-print Network

Volume84, number 2 FEBS LETTERS December 1977 EFFECTS OF WASHING AND OSMOTIC SHOCK ON CATALASE] ). Since catalase causes release of oxygen from hydrogen peroxide, an enhancement of net oxygen evolution on addition of catalase to illuminated chloroplasts indicates that photosynthetic reduction of oxygen has

Allen, John F.


MJD05-018 revised version July 22, 2005 1 Association of CAT polymorphisms with catalase activity and  

E-print Network

MJD05-018 revised version July 22, 2005 1 Association of CAT polymorphisms with catalase activity that catalase activity is modified by CAT single nucleotide polymorphisms (SNPs) (­262 factor (TNF, - 308) in 196 miners. Erythrocyte catalase, superoxide dismutase, and glutathione peroxidase

Paris-Sud XI, Université de


Comparison of the California Mastitis Test, Catalase Test, and pH Readings on Quarter Milk Samples  

Microsoft Academic Search

Three representative groups from 611 quarter samples of aseptically collected milk were compared for catalase, pH, and California mastitis test readings. Statistical analysis (determination of correlation coefficient) was applied to 102 of the 611 quarter samples. It was found that the correlation coefficient for catalase and pH reading was more significant than the correlation coefficient of the catalase and CMT

C. T. Raby; P. L. Hubbard; R. H. Cobbins



Cloning and Heterologous Expression of Hematin-Dependent Catalase Produced by Lactobacillus plantarum CNRZ 1228  

PubMed Central

Lactobacillus plantarum CNRZ 1228 exhibited heme-dependent catalase activity under environmental conditions similar to those encountered during sausage fermentation. The 1,455-bp catalase gene (katL) was cloned and encoded a protein of 484 amino acids. Expression of katL in a heterologous host showed that katL encodes a functional catalase. PCR screening of selected strains of lactic acid bacteria for katL indicated the presence of similar genes in other strains of lactobacilli. PMID:14711694

Abriouel, Hikmate; Herrmann, Anette; Stärke, Joachim; Yousif, Nuha M. K.; Wijaya, Agus; Tauscher, Bernhard; Holzapfel, Wilhelm; Franz, Charles M. A. P.



OxyR regulated the expression of two major catalases, KatA and KatB, along with peroxiredoxin, AhpC in Pseudomonas putida.  


OxyR is known to activate/repress the expression of the oxyR regulon, which consists of several genes, which play important antioxidant role in Escherichia coli. To elucidate the role of OxyR in Pseudomonas putida KT2442, the oxyR1 mutation that caused the upregulation of ahpC in a toluene-resistant variant strain was introduced, because no null mutants in oxyR were isolated. This mutation was shown to cause the accumulation of a catalase (KatA) along with AhpC throughout the growth, and of a RpoS-dependent catalase/peroxidase (KatB) in the stationary phase. Following the identification of the transcription start site of two catalase genes, sequences similar to those involved in the proposed OxyR binding for E. coli were found upstream from each of the promoter regions of katA and katB, as well as ahpC. Purified OxyR was shown to bind to these sequences, under both reduced and oxidized states. Moreover, the oxyR1 mutation increased the transcription levels of these genes. These results are consistent with the conclusion, distinct from those observed in an opportunistic pathogen Pseudomonas aeruginosa, that OxyR controlled expression of all the principal peroxide-degrading enzymes in P. putida. The mutation did not cause any notable changes in the transcriptional levels of several antioxidant genes, including those of glutathione reductase, glutaredoxins and thioredoxins, which would involve maintenance of the cellular thiol-disulfide balance, suggesting that the transcriptional regulation of these antioxidant genes should be different from that of katA, katB and ahpC in P. putida. PMID:17107553

Hishinuma, Sota; Yuki, Masahiro; Fujimura, Makoto; Fukumori, Fumiyasu



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


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. PMID:10333558

Fiedurek, J; Gromada, A; Pielecki, J



Spectroscopic study on the interaction of catalase with bifendate and analogs  

NASA Astrophysics Data System (ADS)

The interactions of bifendate (DDB) or analogs (Bicyclol, I, II and III) with catalase are analyzed by spectrophotometric methods. The fluorescence spectra results show the intrinsic fluorescence of catalase is strongly quenched by DDB or analogs with a static quenching procedure. The binding constants are obtained at three temperatures. The thermodynamics parameters (?H, ?S, ?G) indicate the hydrophobic and electrostatic interactions play a major role in the interaction. The results of synchronous fluorescence, UV-vis absorption and three-dimensional fluorescence spectra demonstrate that the microenvironments of Trp residue of catalase are disturbed by the analogs. Thermodynamic results showed that DDB is the strongest quencher and bind to catalase with the highest affinity among five compounds.

Wang, Ruiqiang; Zhang, Lu; Wang, Rui; Dou, Huanjing; Li, Hua; Wang, Yi; Pu, Juanjuan; Wang, Ruiyong



Serum adenosine deaminase, catalase and carbonic anhydrase activities in patients with bladder cancer  

PubMed Central

OBJECTIVES: The relationship between adenosine deaminase and various cancers has been investigated in several studies. However, serum adenosine deaminase activity and carbonic anhydrase and catalase activities in patients with bladder cancer have not previously been reported. Therefore, the aim of this study was to measure serum adenosine deaminase, carbonic anhydrase and catalase activities in patients with bladder cancer. MATERIALS AND METHODS: Forty patients with bladder cancer and 30 healthy controls were enrolled in the study. Serum adenosine deaminase, carbonic anhydrase and catalase activities were measured spectrophotometrically. RESULTS: Serum adenosine deaminase, carbonic anhydrase and catalase activities were significantly higher in patients with bladder cancer than controls (all significant, p<0.001). CONCLUSIONS: These markers might be a potentially important finding as an additional diagnostic biochemical tool for bladder cancer. PMID:23295599

Pirinççi, Necip; Geçit, ?lhan; Güne?, Mustafa; Bilgehan Y?ksel, Mehmet; Kaba, Mehmet; Tan?k, Serhat; Demir, Halit; Aslan, Mehmet



Catalase Activity of Mouse Liver and its Relation to the Condition of the Animal  

Microsoft Academic Search

IN papers dealing with methods of determining catalase activity in animal tissue, while dealing with the experimental conditions, usually little attention is paid to the condition of the animal. We have found the latter to be of utmost importance.

K. G. van Senden; J. de Jong



High resistance to oxidative damage in the Antarctic midge Belgica antarctica, and developmentally linked expression of genes encoding superoxide dismutase, catalase and heat shock proteins.  


Intense ultraviolet radiation, coupled with frequent bouts of freezing-thawing and anoxia, have the potential to generate high levels of oxidative stress in Antarctic organisms. In this study, we examined mechanisms used by the Antarctic midge, Belgica antarctica, to counter oxidative stress. We cloned genes encoding two key antioxidant enzymes, superoxide dismutase (SOD) and catalase (Cat), and showed that SOD mRNA was expressed continuously and at very high levels in larvae, but not in adults, while Cat mRNA was expressed in both larvae and adults but at a somewhat reduced level. SOD mRNA was expressed at even higher levels in larvae that were exposed to direct sunlight. Catalase, a small heat shock protein, Hsp70 and Hsp90 mRNAs were also strongly upregulated in response to sunlight. Total antioxidant capacity of the adults was higher than that of the larvae, but levels in both stages of the midge were much higher than observed in a freeze-tolerant, temperate zone insect, the gall fly Eurosta solidaginis. Assays to measure oxidative damage (lipid peroxidation TBARS and carbonyl proteins) demonstrated that the Antarctic midge is highly resistant to oxidative stress. PMID:18625403

Lopez-Martinez, Giancarlo; Elnitsky, Michael A; Benoit, Joshua B; Lee, Richard E; Denlinger, David L



Thermal Stability of Catalases Active in Dormant Saffron ( Crocus Sativus L. ) Corms  

Microsoft Academic Search

Catalase activity was detected in crude extract prepared from dormant saffron (Crocus sativus L.) corms. The activity was independent of pH in the range 6.0 – 11.0. Thermostability studies suggested the presence of three isoenzymes with transition temperatures of 30°C, 45°C and 60°C, respectively, as given by Arrhenius plots. When stained for catalase activity gel electropherograms of extract revealed 3

J. Keyhani; E. Keyhani; J. Kamali



Protective action of midgut catalase in lepidopteran larvae against oxidative plant defenses  

Microsoft Academic Search

Catalase activity was detected in the midgut tissues and regurgitate of several lepidopteran pests of the tomato plant. Greatest activity in the midgut was detected in larvalHelicoverpa zea, followed bySpodoptera exigua, Manduca sexta, andHeliothis virescens. We present evidence that catalase, in addition to removing toxic hydrogen peroxide, may inhibit the oxidation of plant phenolics mediated by plant peroxidases. Small amounts

Gary W. Felton; Sean S. Duffey



Adventitial gene transfer of catalase attenuates angiotensin II-induced vascular remodeling.  


Vascular adventitia and adventitia?derived reactive oxygen species (ROS) contribute to vascular remodeling following vascular injury. A previous ex vivo study in adventitial fibroblasts showed that catalase, one of most important anti?oxide enzymes, was downregulated by angiotensin II (AngII). The aim of the present study was to investigate whether adventitial gene transfer of catalase affects AngII?induced vascular remodeling in vivo. Adenoviruses co?expressing catalase and enhanced green fluorescent protein (eGFP) or expressing eGFP only were applied to the adventitial surface of common carotid arteries of Sprague?Dawley rats. Alzet minipumps administering AngII (0.75 mg/kg/day) were then implanted subcutaneously for 14 days. Systolic blood pressure and biological parameters of vascular remodeling were measured in each group. Adventitial fibroblasts were cultured and p38 mitogen?activated protein kinase (MAPK) phosphorylation was measured using western blot analysis. The results showed that adventitial gene transfer of catalase had no effect on AngII?induced systolic blood pressure elevation. However, catalase adenovirus transfection significantly inhibited AngII?induced media hypertrophy compared with that of the control virus (P<0.05). In addition, catalase transfection significantly attenuated AngII?induced ROS generation, macrophage infiltration, collagen deposition and adventitial ??smooth muscle actin expression. Furthermore, catalase transfection significantly inhibited the AngII?induced increase in p38MAPK phosphorylation. In conclusion, the results of the present study demonstrated that adventitial gene transfer of catalase significantly attenuated AngII?induced vascular remodeling in rats via inhibition of adventitial p38MAPK phosphorylation. PMID:25503998

Liu, Cun-Fei; Zhang, Jia; Shen, Kai; Gao, Ping-Jin; Wang, Hai-Ya; Jin, Xin; Meng, Chao; Fang, Ning-Yuan



SHP2 binds catalase and acquires a hydrogen peroxide-resistant phosphatase activity via integrin-signaling.  


Here, we examined whether catalase binds SHP2 and alters SHP2 susceptibility to H2O2. Our results indicated that serum and fibrinogen commonly evoked catalase binding to SHP2 in HeLa and A549 cells in a herbimycin-A and TNFalpha sensitive manner. Expression of active catalase nearly 15-fold over control levels in tet-off HeLa cells substantially increased the SHP2 binding, and the catalase-associated SHP2 displayed significantly high phosphatase activities with a H2O2-resistance compared to those with little catalase. Site-directed mutagenesis at 280 abolished the binding capability of catalase to SHP2-SH2 in vitro. These results suggest that catalase-280pYIQV binds SHP2 via integrin-signaling to increase a H2O2-resistant SHP2 activity. PMID:15556604

Yano, Sumio; Arroyo, Nelly; Yano, Noriko



Nitrite-catalase interaction as an important element of nitrite toxicity.  


It was established that nitrite in the presence of chloride, bromide, and thiocyanate decreases the rate of hydrogen peroxide decomposition by catalase. The decrease was recorded by the permanganatometric method and by a method of dynamic calorimetry. Nitrite was not destroyed in the course of the reaction and the total value of heat produced in the process was not changed by its presence. These facts suggest that nitrite induces inhibition of catalase with no change in the essence of the enzymatic process. Even micromolar nitrite concentrations induced a considerable decrease in catalase activity. However, in the absence of chloride, bromide, and thiocyanate inhibition was not observed. In contrast, fluoride protected catalase from nitrite inhibition in the presence of the above-mentioned halides and pseudohalide. As hydrogen peroxide is a necessary factor for triggering a number of important toxic effects of nitrite, the latter increases its toxicity by inhibiting catalase. This was shown by the example of nitrite-induced hemoglobin oxidation. The naturally existing gradient of chloride and other anion concentrations between intra- and extracellular media appears to be the most important mechanism of cell protection from inhibition of intracellular catalase by nitrite. Possible mechanisms of this inhibition are discussed. PMID:12943506

Titov, V Yu; Petrenko, Yu M



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

PubMed Central

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

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



Redundant Catalases Detoxify Phagocyte Reactive Oxygen and Facilitate Histoplasma capsulatum Pathogenesis  

PubMed Central

Histoplasma capsulatum is a respiratory pathogen that infects phagocytic cells. The mechanisms allowing Histoplasma to overcome toxic reactive oxygen molecules produced by the innate immune system are an integral part of Histoplasma's ability to survive during infection. To probe the contribution of Histoplasma catalases in oxidative stress defense, we created and analyzed the virulence defects of mutants lacking CatB and CatP, which are responsible for extracellular and intracellular catalase activities, respectively. Both CatB and CatP protected Histoplasma from peroxide challenge in vitro and from antimicrobial reactive oxygen produced by human neutrophils and activated macrophages. Optimal protection required both catalases, as the survival of a double mutant lacking both CatB and CatP was lower than that of single-catalase-deficient cells. Although CatB contributed to reactive oxygen species defenses in vitro, CatB was dispensable for lung infection and extrapulmonary dissemination in vivo. Loss of CatB from a strain also lacking superoxide dismutase (Sod3) did not further reduce the survival of Histoplasma yeasts. Nevertheless, some catalase function was required for pathogenesis since simultaneous loss of both CatB and CatP attenuated Histoplasma virulence in vivo. These results demonstrate that Histoplasma's dual catalases comprise a system that enables Histoplasma to efficiently overcome the reactive oxygen produced by the innate immune system. PMID:23589579

Holbrook, Eric D.; Smolnycki, Katherine A.; Youseff, Brian H.



Generation 9 polyamidoamine dendrimer encapsulated platinum nanoparticle mimics catalase size, shape, and catalytic activity.  


Poly(amidoamine) (PAMAM) encapsulated platinum nanoparticles were synthesized and used as catalase mimics. Acetylated generation 9 (Ac-G9) PAMAM dendrimer with a molecular size around 10 nm was used as a template to synthesize platinum nanoparticles. The feeding molar ratio of Pt(4+) and Ac-G9 is 2048, and the synthesized platinum nanoparticle (Ac-G9/Pt NP) has an average size of 3.3 nm. Ac-G9/Pt NP has a similar molecular size and globular shape with catalase (~11 nm). The catalytic activity of Ac-G9/Pt NP on the decomposition of H2O2 is approaching that of catalase at 37 °C. Ac-G9/Pt NP shows differential response to the changes of pH and temperature compared with catalase, which can be explained by different catalytic mechanisms of Ac-G9/Pt NP and catalase. Ac-G9/Pt NP also shows horseradish peroxidase activity and is able to scavenge free radicals such as di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium (DPPH). Furthermore, Ac-G9/Pt NP shows excellent biocompatibility on different cell lines and can down-regulate H2O2-induced intracellular reactive oxygen species (ROS) in these cells. These results suggest that dendrimers are promising mimics of proteins with different sizes and Ac-G9/Pt NP can be used as an alternative candidate of catalase to decrease oxidation stress in cells. PMID:23544351

Wang, Xinyu; Zhang, Yincong; Li, Tianfu; Tian, Wende; Zhang, Qiang; Cheng, Yiyun



Purification and Characterization of a Novel Thermo-Alkali-Stable Catalase from Thermus brockianus  

SciTech Connect

A novel thermo-alkali-stable catalase from Thermus brockianus was purified and characterized. The protein was purified from a T. brockianus cell extract in a three-step procedure that resulted in 65-fold purification to a specific activity of 5300 U/mg. The enzyme consisted of four identical subunits of 42.5 kDa as determined by SDS-PAGE and a total molecular mass measured by gel filtration of 178 kDa. The catalase was active over a temperature range from 30 to 94 C and a pH range from 6 to 10, with optimum activity occurring at 90 C and pH 8. At pH 8, the enzyme was extremely stable at elevated temperatures with half-lives of 330 h at 80 C and 3 h at 90 C. The enzyme also demonstrated excellent stability at 70 C and alkaline pH with measured half-lives of 510 h and 360 h at pHs of 9 and 10, respectively. The enzyme had an unusual pyridine hemochrome spectrum and appears to utilize eight molecules of heme c per tetramer rather than protoheme IX present in the majority of catalases studied to date. The absorption spectrum suggested that the heme iron of the catalase was in a 6-coordinate low spin state rather than the typical 5-coordinate high spin state. A Km of 35.5 mM and a Vmax of 20.3 mM/min·mg protein for hydrogen peroxide was measured, and the enzyme was not inhibited by hydrogen peroxide at concentrations up to 450 mM. The enzyme was strongly inhibited by cyanide and the traditional catalase inhibitor 3-amino-1,2,4-triazole. The enzyme also showed no peroxidase activity to peroxidase substrates o-dianisidine and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), a trait of typical monofunctional catalases. However, unlike traditional monofunctional catalases, the T. brockianus catalase was easily reduced by dithionite, a characteristic of catalase-peroxidases. The above properties indicate that this catalase has potential for applications in industrial bleaching processes to remove residual hydrogen peroxide from process streams.

Thompson, Vicki Sue; Schaller, Kastli Dianne; Apel, William Arnold



Catalase is a sink for H2O2 and is indispensable for stress defence in C3 plants.  

PubMed Central

Hydrogen peroxide (H2O2) has been implicated in many stress conditions. Control of H2O2 levels is complex and dissection of mechanisms generating and relieving H2O2 stress is difficult, particularly in intact plants. We have used transgenic tobacco with approximately 10% wild-type catalase activity to study the role of catalase and effects of H2O2 stress in plants. Catalase-deficient plants showed no visible disorders at low light, but in elevated light rapidly developed white necrotic lesions on the leaves. Lesion formation required photorespiratory activity since damage was prevented under elevated CO2. Accumulation of H2O2 was not detected during leaf necrosis. Alternative H2O2-scavenging mechanisms may have compensated for reduced catalase activity, as shown by increased ascorbate peroxidase and glutathione peroxidase levels. Leaf necrosis correlated with accumulation of oxidized glutathione and a 4-fold decrease in ascorbate, indicating that catalase is critical for maintaining the redox balance during oxidative stress. Such control may not be limited to peroxisomal H2O2 production. Catalase functions as a cellular sink for H2O2, as evidenced by complementation of catalase deficiency by exogenous catalase, and comparison of catalase-deficient and control leaf discs in removing external H2O2. Stress analysis revealed increased susceptibility of catalase-deficient plants to paraquat, salt and ozone, but not to chilling. PMID:9305623

Willekens, H; Chamnongpol, S; Davey, M; Schraudner, M; Langebartels, C; Van Montagu, M; Inzé, D; Van Camp, W



Reduction of Hydrogen Peroxide Accumulation and Toxicity by a Catalase from Mycoplasma iowae  

PubMed Central

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. PMID:25127127

Pritchard, Rachel E.; Prassinos, Alexandre J.; Osborne, John D.; Raviv, Ziv; Balish, Mitchell F.



Cardiac overexpression of antioxidant catalase attenuates aging-induced cardiomyocyte relaxation dysfunction.  


Catalase, an enzyme which detoxifies H2O2, may interfere with cardiac aging. To test this hypothesis, contractile and intracellular Ca2+ properties were evaluated in cardiomyocytes from young (3-4 months) and old (26-28 months) FVB and transgenic mice with cardiac overexpression of catalase. Contractile indices analyzed included peak shortening (PS), time-to-90% PS (TPS90), time-to-90% relengthening (TR90), half-width duration (HWD), maximal velocity of shortening/relengthening (+/-dL/dt) and intracellular Ca2+ levels or decay rate. Levels of advanced glycation endproduct (AGE), Na+/Ca2+ exchanger (NCX), sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA2a), phospholamban (PLB), myosin heavy chain (MHC), membrane Ca2+ and K+ channels were measured by western blot. Catalase transgene prolonged survival while did not alter myocyte function by itself. Aging depressed+/-dL/dt, prolonged HWD, TR90 and intracellular Ca2+ decay without affecting other indices in FVB myocytes. Aged FVB myocytes exhibited a stepper decline in PS in response to elevated stimulus or a dampened rise in PS in response to elevated extracellular Ca2+ levels. Interestingly, aging-induced defects were nullified or significantly attenuated by catalase. AGE level was elevated by 5-fold in aged FVB compared with young FVB mice, which was reduced by catalase. Expression of SERCA2a, NCX and Kv1.2 K+ channel was significantly reduced although levels of PLB, L-type Ca2+ channel dihydropyridine receptor and beta-MHC isozyme remained unchanged in aged FVB hearts. Catalase restored NCX and Kv1.2 K+ channel but not SERCA2a level in aged mice. In summary, our data suggested that catalase protects cardiomyocytes from aging-induced contractile defect possibly via improved intracellular Ca2+ handling. PMID:17250874

Ren, Jun; Li, Qun; Wu, Shan; Li, Shi-Yan; Babcock, Sara A



Catalase HPII from Escherichia coli Exhibits Enhanced Resistance to Denaturation Jacek Switala, Joe O. O'Neil, and Peter C. Loewen*,  

E-print Network

Catalase HPII from Escherichia coli Exhibits Enhanced Resistance to Denaturation Jacek Switala, Joe 11, 1999 ABSTRACT: Catalase HPII from Escherichia coli is a homotetramer of 753 residue subunits of the enzyme. For comparison, catalase-peroxidase HPI of E. coli and bovine liver catalase are 50% inactivated

O'Neil, Joe


Decrease of hepatic catalase level by treatment with diallyl sulfide and garlic homogenates in rats and mice.  


Diallyl sulfide (DAS) is a flavor compound derived from garlic and is active in the inhibition of chemically induced cytotoxicity and carcinogenicity in animal models. This study was conducted to examine the effects of the treatment of DAS and garlic homogenates on the activities of catalase, glutathione peroxidase, and superoxide dismutase. Male Sprague-Dawley rats were treated with DAS i.g. at daily doses of 50 or 200 mg/kg for 8 days, causing the hepatic catalase activity to decrease by 55 and 95%, respectively. Such a decrease in hepatic catalase activity was also observed when the DAS treatment was extended to 29 days. Western blot analysis showed that the DAS treatments resulted in corresponding decreases in the liver catalase protein level. No significant change in the catalase activity in the kidney, lung, and brain was observed with the treatments, but a slight decrease in heart catalase activity was observed. These treatments did not cause significant changes in superoxide dismutase and glutathione peroxidase activities in these tissues. Treatment with DAS at a daily dose of 200 mg/kg for 1-7 days resulted in a gradual decrease in the liver catalase activity to 5% of the control level, but it did not decrease the erythrocyte catalase activity. Treatment of rats with fresh garlic homogenates (2 or 4 g/kg, i.g., daily for 7 days) caused a 35% decrease in liver catalase activity. A/J mice treated with DAS and garlic homogenates also showed a decrease in the liver catalase activity. Diallyl sulfone (DASO2), a DAS metabolite, however, did not effectively decrease catalase activity in mice. The catalase activity was not inhibited by either DAS or DASO2 in vitro. The present results demonstrate that treatment with DAS and garlic homogenates decrease the hepatic catalase level in rats and mice. PMID:10098897

Chen, L; Hong, J Y; So, E; Hussin, A H; Cheng, W F; Yang, C S



Kinetics and mechanisms of catalase in peroxisomes of the mitochondrial fraction.  


1. The primary intermediate of catalase and hydrogen peroxide was identified and investigated in peroxisome-rich mitochondrial fractions of rat liver. On the basis of kinetic constants determined in vitro, it is possible to calculate with reasonable precision the molecular statistics of catalase action in the peroxisomes. 2. The endogenous hydrogen peroxide generation is adequate to sustain a concentration of the catalase intermediate (p(m)/e) of 60-70% of the hydrogen peroxide saturation value. Total amount of catalase corresponds to 0.12-0.15nmol of haem iron/mg of protein. In State 1 the rate of hydrogen peroxide generation corresponds to 0.9nmol/min per mg of protein or 5% of the mitochondrial respiratory rate in State 4. 3. Partial saturation of the catalase intermediate with hydrogen peroxide (p(m)/e) in the mitochondrial fraction suggests its significant peroxidatic activity towards its endogenous hydrogen donor. A variation of this value (p(m)/e) from 0.3 in State 4 to 0 under anaerobic conditions is observed. 4. For a particular preparation the hydrogen peroxide generation rate in the substrate-supplemented State 4 corresponds to 0.17s(-1) (eqn. 6), the hydrogen peroxide concentration to 2.5nm and the hydrogen-donor concentration (in terms of ethanol) to 0.12mm. The reaction is 70% peroxidatic and 30% catalatic. 5. A co-ordinated production of both oxidizing and reducing substrates for catalase in the mitochondrial fraction is suggested by a 2.2-fold increase of hydrogen peroxide generation and a threefold increase in hydrogen-donor generation in the State 1 to State 4 transition. 6. Additional hydrogen peroxide generation provided by the urate oxidase system of peroxisomes (8-12nmol of uric acid oxidized/min per mg of protein) permits saturation of the catalase with hydrogen peroxide to haem occupancy of 40% compared with values of 36% for a purified rat liver catalase ofk(1)=1.7x10(7)m(-1).s(-1) and k'(4)=2.6x10(7)m(-1). s(-1)(Chance, Greenstein & Roughton, 1952). 7. The turnover of the catalase ethyl hydrogen peroxide intermediate (k'(3)) in the peroxisomes is initially very rapid since endogenous hydrogen peroxide acts as a hydrogen donor. k'(3) decreases fivefold in the uncoupled state of the mitochondria. PMID:5117568

Chance, B; Oshino, N



Purification and characterization of oxygen-inducible haem catalase from oxygen-tolerant Bifidobacterium asteroides.  


Bifidobacterium asteroides, originally isolated from honeybee intestine, was found to grow under 20% O(2) conditions in liquid shaking culture using MRS broth. Catalase activity was detected only in cells that were exposed to O(2) and grown in medium containing a haem source, and these cells showed higher viability on exposure to H(2)O(2). Passage through multiple column chromatography steps enabled purification of the active protein, which was identified as a homologue of haem catalase on the basis of its N-terminal sequence. The enzyme is a homodimer composed of a subunit with a molecular mass of 55 kDa, and the absorption spectrum shows the typical profile of bacterial haem catalase. A gene encoding haem catalase, which has an amino acid sequence coinciding with the N-terminal amino acid sequence of the purified protein, was found in the draft genome sequence data of B. asteroides. Expression of the katA gene was induced in response to O(2) exposure. The haem catalase from B. asteroides shows about 70-80% identity with those from lactobacilli and other lactic acid bacteria, and no homologues were found in other bifidobacterial genomes. PMID:23154971

Hayashi, Kyohei; Maekawa, Itaru; Tanaka, Kunifusa; Ijyuin, Susumu; Shiwa, Yu; Suzuki, Ippei; Niimura, Youichi; Kawasaki, Shinji



The oxidation of chiral alcohols catalyzed by catalase in organic solvents  

SciTech Connect

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.

Magner, E.; Klibanov, A.M. [Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Chemistry



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

SciTech Connect

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 at 0.5 days to 4.6 +/- 0.2 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)

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



Production of catalases by Aspergillus niger isolates as a response to pollutant stress by heavy metals  

SciTech Connect

Isolates of Aspergillus niger, selected from the coal dust of a mine containing arsenic (As; 400 mg/kg) and from the river sediment of mine surroundings (As, 1651 mg/kg, Sb, 362 mg/kg), growing in minimal nitrate medium in the phase of hyphal development and spore formation, exhibited much higher levels of total catalase activity than the same species from the culture collection or a culture adapted to soil contaminated with As (5 mg/L). Electrophoretic resolution of catalases in cell-free extracts revealed three isozymes of catalases and production of individual isozymes was not significantly affected by stress environments. Exogenously added stressors (As{sup 5+}, Cd{sup 2+}, Cu{sup 2+}) at final concentrations of 25 and 50 mg/L and H{sub 2}O{sub 2} (20 or 40 m(M)) mostly stimulated production of catalases only in isolates from mines surroundings, and H{sub 2}O{sub 2} and Hg{sup 2+} caused the disappearance of the smallest catalase I. Isolates exhibited a higher tolerance of the toxic effects of heavy metals and H{sub 2}O{sub 2}, as monitored by growth, than did the strain from the culture collection.

Buckova, M.; Godocikova, J.; Simonovicova, A.; Polek, B. [Slovakian Academy of Science, Bratislava (Slovakia)



Targeting Catalase but Not Peroxiredoxins Enhances Arsenic Trioxide-Induced Apoptosis in K562 Cells  

PubMed Central

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. PMID:25115845

Wang, Wei-Wei; Wei, Wei; Ma, Chun-Min; Wen, Dong-Hua; Lei, Hu; Xu, Han-Zhang; Wu, Ying-Li



Catalase: a tetrameric enzyme with four tightly bound molecules of NADPH.  

PubMed Central

Catalases (H2O2:H2O2 oxidoreductase, EC from many species are known to be tetramers of 60,000-dalton subunits, with four heme groups per tetramer. Previous authors have determined the amino acid sequence and three-dimensional structure of bovine liver catalase. Studies of the regulation of the pentose phosphate pathway led the present authors to a search for proteins that bind NADP+ and NADPH in human erythrocytes. An unexpected result of that search was the finding that a major reservoir of bound NADPH in human erythrocytes is catalase. Each tetrameric molecule of human or bovine catalase contains four molecules of tightly bound NADPH. The binding sites have the relative affinities NADPH greater than NADH greater than NADP+ greater than NAD+. NADPH does not seem to be essential for the enzymic conversion of H2O2 to O2 and water but does provide protection of catalase against inactivation by H2O2. PMID:6589599

Kirkman, H N; Gaetani, G F



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


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 ?M). 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. PMID:24887508

Bekde?er, Burcu; Özyürek, Mustafa; Güçlü, Kubilay; Alkan, Fulya Üstün; Apak, Re?at



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

PubMed Central

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

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



Catalase is a sink for H2O2 and is indispensable for stress defence in C3 plants  

Microsoft Academic Search

Hydrogen peroxide (H2O2) has been implicated in many stress conditions. Control of H2O2 levels is complex and dissection of mechanisms generating and relieving H2O2 stress is difficult, particularly in intact plants. We have used transgenic tobacco with ?10% wild-type catalase activity to study the role of catalase and effects of H2O2 stress in plants. Catalase-deficient plants showed no visible disorders

Hilde Willekens; Sangpen Chamnongpol; Mark Davey; Martina Schraudner; Christian Langebartels; Dirk Inzé; Wim Van Camp; Marc Van Montagu



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

Microsoft Academic Search

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




Endothelin1 Upregulates MCAM in Melanocytes  

Microsoft Academic Search

Melanoma cell adhesion molecule (MCAM) is a cell-surface adhesion molecule expressed on over 70% of metastatic melanoma cells but not expressed in normal melanocytes invivo. Protein levels of MCAM correlate with aggressive invasive behavior of melanoma cells in vitro and invivo. Here we demonstrate that endothelin-1 (ET-1) upregulates MCAM protein in primary human melanocytes. MCAM upregulation by ET-1 occurs irrespective

Catherine R. Mangahas; Gelo V. dela Cruz; Robert J. Schneider; Sumayah Jamal



Layer-by-layer assembled multilayers using catalase-encapsulated gold nanoparticles  

NASA Astrophysics Data System (ADS)

We introduce a novel and versatile approach for the preparation of multilayers, based on catalase-encapsulated gold nanoparticles (CAT-AuNP), allowing electrostatic charge reversal and structural transformation through pH adjustment. CAT-AuNP, which are synthesized directly from CAT stabilizer, can be electrostatically assembled with anionic and cationic PEs as a result of the charge reversal of the catalase stabilizers through pH control. In particular, at pH 5.2, near the pI of catalase, dispersed CAT-AuNP are structurally transformed into colloidal or network CAT-AuNP nanocomposites. Furthermore, we demonstrate that the layer-by-layer assembled multilayers composed of PEs and CAT-AuNP induce an effective electron transfer between CAT and the electrode as well as a high loading of CAT and AuNP, and resultantly exhibit a highly catalytic activity toward H2O2.

Kim, Sungwoo; Park, Jeongju; Cho, Jinhan



Influence of Catalase and Superoxide Dismutase on Ozone Inactivation of Listeria monocytogenes  

PubMed Central

The effects of ozone at 0.25, 0.40, and 1.00 ppm on Listeria monocytogenes were evaluated in distilled water and phosphate-buffered saline. Differences in sensitivity to ozone were found to exist among the six strains examined. Greater cell death was found following exposure at lower temperatures. Early stationary-phase cells were less sensitive to ozone than mid-exponential- and late stationary-phase cells. Ozonation at 1.00 ppm of cabbage inoculated with L. monocytogenes effectively inactivated all cells after 5 min. The abilities of in vivo catalase and superoxide dismutase to protect the cells from ozone were also examined. Three listerial test strains were inactivated rapidly upon exposure to ozone. Both catalase and superoxide dismutase were found to protect listerial cells from ozone attack, with superoxide dismutase being more important than catalase in this protection. PMID:10742219

Fisher, Christopher W.; Lee, Dongha; Dodge, Beth-Anne; Hamman, Kristen M.; Robbins, Justin B.; Martin, Scott E.



Enzymatic exploration of catalase from a nanoparticle producing and biodecolorizing algae Shewanella xiamenensis BC01.  


Shewanella xiamenensis (SXM) was found to produce nanoparticles (NPs) under aerobic condition. The oxidoreductase enzymatic activities including of catalase, manganese peroxidase, laccase, NADH dehydrogenase, flavin reductase, azoreductase and Fe reductase are first investigated. Catalase showed the greatest enzymatic activity among all oxidoreductases in SXM, which with strong activities in multiple substrates of ABTS, guaiacol and 2,6-DMP. The optimum temperature, pH, concentrations of H2O2 and 2,6-DMP for this enzyme were found to be 65°C, pH 4.0, 128.7mM and 10mM, respectively. Finally, from the kinetic parameters and structure simulation of catalase, implied that SXM would potentially apply in bioremediation, microbe fuel cells (MFCs) and nano-biotechnology based on its distinguished enzymatic system. PMID:25306444

Ng, I-Son; Xu, Fangxin; Zhang, Xia; Ye, Chiming



Purification and characterization of the Mycobacterium smegmatis catalase-peroxidase involved in isoniazid activation.  


The unique antitubercular activity of isoniazid requires that the drug be oxidized by the katG-encoded mycobacterial catalase-peroxidase to an activated drug form. In order to quantitatively assess the catalytic capabilities of the enzyme, the native catalase-peroxidase from Mycobacterium smegmatis was purified over 200-fold to homogeneity. The enzyme was shown to exhibit both catalase and peroxidase activities, and in the presence of either hydrogen peroxide or t-butyl peroxide, was found to catalyze the oxidation of the reduced pyridine nucleotides, NADH and NADPH, as well as artificial peroxidase substrates, at rates between 2.7 and 20 s-1. The homogeneous enzyme exhibited a visible absorbance spectrum typical of ferric heme-containing catalase-peroxidases, with a Soret maximum at 406 nm. Low temperature (10 K) electron paramagnetic resonance spectra in the presence of ethylene glycol revealed a high spin Fe(III) signal with g values of 5.9 and 5.6. The enzyme was very slowly (t1/2 = approximately 20 min) reduced by dithionite, and the reduced form showed typical spectral changes when either KCN or CO were subsequently added. The M. smegmatis catalase-peroxidase was found to contain 2 heme molecules per tetramer, which were identified as iron protoporphyrin IX by the pyridine hemochromogen assay. The peroxidatic activity was inhibited by KCN, NaN3, isoniazid (isonicotinic acid hydrazide), and its isomer, nicotinic acid hydrazide, but not by 3-amino-1,2,4-triazole. The role of mycobacterial catalase-peroxidases in the oxidative activation of the antitubercular prodrug isoniazid is discussed. PMID:7673210

Marcinkeviciene, J A; Magliozzo, R S; Blanchard, J S



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


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. PMID:21170678

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



Cloning and characterization of katA, encoding the major monofunctional catalase from Xanthomonas campestris pv. phaseoli and characterization of the encoded catalase KatA.  


The first cloning and characterization of the gene katA, encoding the major catalase (KatA), from Xanthomonas is reported. A reverse genetic approach using a synthesized katA-specific DNA probe to screen a X. campestris pv. phaseoli genomic library was employed. A positively hybridizing clone designated pKat29 that contained a full-length katA was isolated. Analysis of the nucleotide sequence revealed an open reading frame of 1,521 bp encoding a 507-amino acid protein with a theoretical molecular mass of 56 kDa. The deduced amino acid sequence of KatA revealed 84% and 78% identity to CatF of Pseudomonas syringae and KatB of P. aeruginosa, respectively. Phylogenetic analysis places Xanthomonas katA in the clade I group of bacterial catalases. Unexpectedly, expression of katA in a heterologous Escherichia coli host resulted in a temperature-sensitive expression. The KatA enzyme was purified from an overproducing mutant of X. campestris and was characterized. It has apparent K(m) and V(max) values of 75 m M [H(2)O(2)] and 2.55 x 10(5) micromol H(2)O(2) micromol heme(-1) s(-1), respectively. The enzyme is highly sensitive to 3-amino-1,2,4-triazole and NaN(3), has a narrower optimal pH range than other catalases, and is more sensitive to heat inactivation. PMID:12520360

Chauvatcharin, Nopmanee; Vattanaviboon, Paiboon; Switala, Jack; Loewen, Peter C; Mongkolsuk, Skorn



The Association between Adult Asthma and Superoxide Dismutase and Catalase Gene Activity  

Microsoft Academic Search

Background: Adult asthma is caused by interaction effects of multiple genetic and environmental factors. Some studies have suggested that antioxidant enzyme activity and gene polymorphisms may play important roles in the context of asthma. Therefore, our study objectives were to investigate the association between asthma, antioxidant activities and the polymorphisms of manganese superoxide dismutase (Mn-SOD) or catalase (CAT). Materials and

Li-Ling Yang; Ming-Shyan Huang; Chi-Chih Huang; Tung-Heng Wang; Meng-Chih Lin; Chao-Chien Wu; Chin-Chou Wang; Shao-Hua Lu; Tsu-Yu Yuan; Yen-Hsiung Liao; Ying-Chin Ko; Tsu-Nai Wang



The Serum Levels of Malondialdehyde, Vitamin E and Erythrocyte Catalase Activity in Psoriasis Patients  

PubMed Central

Background: Psoriasis is a common skin disease which is characterized by increased epidermal proliferation and dermal inflammation affecting 0.1-3% of general population. Most of the psoriasis patients are young or middle aged adults, although no age exempted. The oxidative stress develops due to imbalance in oxidants and antioxidants, which was proposed to have role in psoriasis. Aims and Objectives: The presented research work was planned to evaluate oxidative stress by measuring serum malondialdehyde (MDA) as oxidant and serum vitamin E, erythrocyte catalase (CAT) activity as antioxidants in psoriasis patients. Materials and Methods: Total 90 clinically diagnosed psoriasis patients of age group of 20 to 60 years and without any drug therapy for preceding two months and 90 matched healthy controls were included in the presented study. The severity of psoriasis was determined by PASI score. The fasting blood sample collected and accessed for serum MDA, serum vitamin E and erythrocyte catalase activity. Results: The study results were compiled and statistical analysis was done using students t-test. Our results showed significantly increased levels of serum MDA (p<0.001) and significantly decreased serum vitamin E (p<0.001) as well as erythrocyte catalase activity (p<0.001) in psoriasis patients as compared to controls. Conclusion: The presented study concluded the oxidative stress in psoriasis, indicated by increased serum MDA and decreased Vitamin E, erythrocyte catalase activity. Our study also supports the possibility of involvement of oxidative stress in pathogenesis of psoriasis. PMID:25584212

Ireddy, Shankargouda; Itagi, Inderraj; Kumar H., Siddesh



The 2.0 A crystal structure of catalase-peroxidase from Haloarcula marismortui.  


Catalase-peroxidase is a member of the class I peroxidase superfamily. The enzyme exhibits both catalase and peroxidase activities to remove the harmful peroxide molecule from the living cell. The 2.0 A crystal structure of the catalase-peroxidase from Haloarcula marismortui (HmCP) reveals that the enzyme is a dimer of two identical subunits. Each subunit is composed of two structurally homologous domains with a topology similar to that of class I peroxidase. The active site of HmCP is in the N-terminal domain. Although the arrangement of the catalytic residues and the cofactor heme b in the active site is virtually identical to that of class I peroxidases, the heme moiety is buried inside the domain, similar to that in a typical catalase. In the vicinity of the active site, novel covalent bonds are formed among the side chains of three residues, including that of a tryptophan on the distal side of the heme. Together with the C-terminal domain, these covalent bonds fix two long loops on the surface of the enzyme that cover the substrate access channel to the active site. These features provide an explanation for the dual activities of this enzyme. PMID:12172540

Yamada, Yusuke; Fujiwara, Taketomo; Sato, Takao; Igarashi, Noriyuki; Tanaka, Nobuo



Effect of Iron Deficiency on Gas Exchange and Catalase and Peroxidase Activity in Citrus  

Microsoft Academic Search

The effects of iron (Fe) deficiency on catalase and peroxidase activity, net photosynthesis (Pn), stomatal conductance (gs), plant water relations, and specific leaf weight, were studied under greenhouse conditions in two sweet orange (C. sinensis) cultivars grafted on sour orange (Citrus aurantium) and Swingle citrumelo (C. paradisi × P. trifoliata). Iron deficiency caused by the absence of Fe in the Hoagland nutrient

Vassilios Chouliaras; Ioannis Therios; Athanassios Molassiotis; Angelos Patakas; Gregorios Diamantidis



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

SciTech Connect

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.

Whiteside, C.; Hassan, H.M.



Low dose X -ray effects on catalase activity in animal tissue  

NASA Astrophysics Data System (ADS)

This study was intended to investigate the effect of low-dose X ray-irradiation upon the activity of catalase (CAT) in freshly excised chicken tissues (liver, kidney, brain, muscle). The tissue samples were irradiated with 0.5Gy and 2Gy respectively, in a 6 MV photon beam produced by a clinical linear accelerator (VARIAN CLINAC 2100SC). The dose rate was of 260.88cGy/min. at 100 cm source to sample distance. The catalase level was assayed spectrophotometrically, based on reaction kinetics, using a catalase UV assay kit (SIGMA). Catalase increased activity in various tissue samples exposed to the studied X ray doses (for example with 24 % in the liver cells, p<0.05) suggested the stimulation of the antioxidant enzyme biosynthesis within several hours after exposure at doses of 0.5 Gy and 2 Gy; the putative enzyme inactivation could also occur (due to the injuries on the hydrogen bonds that ensure the specificity of CAT active site) but the resulted balance of the two concurrent processes indicates the cell ability of decomposing the hydrogen peroxide-with benefits for the cell physiology restoration for the chosen low dose radiation.

Focea, R.; Nadejde, C.; Creanga, D.; Luchian, T.



Direct evidence for catalase activity of [Ru(V)(edta)(O)](-).  


Reported is the first example of a ruthenium(iii) complex, Ru(III)(edta) (edta(4-) = ethylenediaminetetraacetate), that catalyzes the disproportion of H2O2 to O2 and water in resemblance to catalase activity, and shedding light on the possible mechanism of action of the [Ru(V)(edta)(O)](-) formed in the reacting system. PMID:25307989

Chatterjee, Debabrata; Jaiswal, Namita; Franke, Alicja; van Eldik, Rudi



Secreted catalase activity from roots of developing maize ( Zea mays L.) seedlings  

Microsoft Academic Search

Summary Hydrogen peroxide generation by cell wall and plasma membrane has been demonstrated in several plant materials. However, we do not find appreciable concentrations of hydrogen peroxide in corn (Zea mays L.) roots, but a relatively high catalase activity was observed. The activity was released to the incubation medium and increased with time, while the activity remaining in roots was

J. Salguero; M. Böttger



Catalase C-262T polymorphism and risk of prostate cancer: Evidence from meta-analysis.  


Catalase is an important endogenous antioxidant enzyme that detoxifies hydrogen peroxide to oxygen and water, thus limiting the deleterious effects of reactive oxygen species. Several studies investigated the role of the Catalase (CAT) C-262T gene polymorphism on the risk of prostate cancer (PCa), but get conflicting results. We performed a meta-analysis based on five studies, to determine whether Catalase C-262T polymorphism contributes to the risk of prostate cancer using odds ratios (OR) with 95% confidence intervals (CI). On the whole, our evidence indicates that CAT C-262T polymorphism significantly increases PCa risk in the allele comparison model (OR=1.094, 95% CI=1.015-1.178, P=0.018). In the stratified analysis by ethnicity, the same results are found among Caucasians (allele model, OR=1.090, 95% CI=1.009-1.177, P=0.028, dominant model, OR=1.108, 95% CI=1.023-1.201, P=0.012, recessive model, OR=1.379, 95% CI=1.158-1.641, P=0.000, homozygous model, OR=1.429, 95% CI=1.196-1.707, P=0.000, and heterozygote model, OR=1.224, 95% CI=1.020-1.469, P=0.030). In conclusion, this meta-analysis suggests a positive correlation between Catalase C-262T polymorphism and the development of PCa. PMID:25576221

Hu, Jieping; Feng, Fupeng; Zhu, Shimiao; Sun, Libin; Li, Gang; Jiang, Ning; Shang, Zhiqun; Niu, Yuanjie



Catalase activity measured with a micro oxygen electrode in a pressurized reaction vessel. [Mice, rats  

Microsoft Academic Search

The assembly and the use of a simple airtight pressurized reaction vessel are described for the measurement of catalase activity with a micro oxygen electrode in an optically heterogenous medium. The oxygen concentration is expressed as the ratio of observed current to the current in an air-saturated solution. Thus, an individual standard can be obtained for each measurement and the




Analysis of allelic variants in the catalase gene in patients with the skin depigmenting disorder vitiligo  

Microsoft Academic Search

Vitiligo is an acquired hypomelanotic skin disorder characterised by circumscribed depigmented macules resulting from the loss of functional melanocytes from the cutaneous epidermis. Conditions that might result in epidermal oxidative stress and consequently damage to pigment cells have been reported in the skin of vitiligo patients, including low catalase activity and increases in hydrogen peroxide levels. However, the cause of

Nikos G. Gavalas; Samia Akhtar; David J. Gawkrodger; Philip F. Watson; Anthony P. Weetman; E. Helen Kemp



Catalase Test for Abnormal Milk. I. Techniques and Factors Affecting the Test1  

Microsoft Academic Search

This study was made to compare techniques for testing milk for catalase activity, and to determine the effects of certain experimental variables on the reaction. In the inverted tube test, calibrated centrifuge tubes with outlets of straight glass tubing were most satisfactory. Increase in substrate concentration above 1 ml 3% H~O~ did not significantly increase O~ production at room tem-

G. Nageswararao; H. Blobel; J. B. Derbyshire



Mitochondrial Targeting of a Catalase Transgene Product by Plasmid Liposomes Increases Radioresistance In Vitro and In Vivo  

PubMed Central

To determine whether increased mitochondrially localized catalase was radioprotective, a human catalase transgene was cloned into a small pSVZeo plasmid and localized to the mitochondria of 32D cl 3 cells by adding the mitochondrial localization sequence of MnSOD (mt-catalase). The cell lines 32D-Cat and 32D-mt-Cat had increased catalase biochemical activity as confirmed by Western blot analysis compared to the 32D cl 3 parent cells. The MnSOD-overexpressing 32D cl 3 cell line, 2C6, had decreased baseline catalase activity that was increased in 2C6-Cat and 2C6-mt-Cat subclonal cell lines. 32D-mt-Cat cells were more radioresistant than 32D-Cat cells, but both were radioresistant relative to 32D cl 3 cells. 2C6-mt-Cat cells but not 2C6-Cat cells were radioresistant compared to 2C6 cells. Intratracheal injection of the mt-catalase-plasmid liposome complex (mt-Cat-PL) but not the catalase-plasmid liposome complex (Cat-PL) increased the resistance of C57BL/6NHsd female mice to 20 Gy thoracic irradiation compared to MnSOD-plasmid liposomes. Thus mitochondrially targeted overexpression of the catalase transgene is radioprotective in vitro and in vivo. PMID:19580494

Epperly, Michael W.; Melendez, J. A.; Zhang, Xichen; Nie, Suhua; Pearce, Linda; Peterson, James; Franicola, Darcy; Dixon, Tracy; Greenberger, Benjamin A.; Komanduri, Paavani; Wang, Hong; Greenberger, Joel S.



Purification, crystallization and preliminary crystallographic analysis of KatB, a manganese catalase from Anabaena PCC 7120.  


Catalases are enzymes that play an important role in the detoxification of hydrogen peroxide (H2O2) in aerobic organisms. Among catalases, haem-containing catalases are ubiquitously distributed and their enzymatic mechanism is very well understood. On the other hand, manganese catalases that contain a bimanganese core in the active site have been less well characterized and their mode of action is not fully understood. The genome of Anabaena PCC 7120 does not show the presence of a haem catalase-like gene; instead, two ORFs encoding manganese catalases (Mn-catalases) are present. Here, the crystallization and preliminary X-ray crystallographic analysis of KatB, one of the two Mn-catalases from Anabaena, are reported. KatB was crystallized using the hanging-drop vapour-diffusion method with PEG 400 as a precipitant and calcium acetate as an additive. Diffraction data were collected in-house on an Agilent SuperNova system using a microfocus sealed-tube X-ray source. The crystal diffracted to 2.2?Å resolution at 100?K. The tetragonal crystal belonged to space group P4(1)2(1)2 (or enantiomer), with unit-cell parameters a = b = 101.87, c = 138.86?Å. Preliminary X-ray diffraction analysis using the Matthews coefficient and self-rotation function suggests the presence of a trimer in the asymmetric unit. PMID:24192374

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



Catalase and superoxide dismutase in alfalfa root nodules. [Medicago sativa L  

SciTech Connect

Catalase and superoxide dismutase (SOD), in scavenging H/sub 2/ O/sub 2/ and O/sub 2/, respectively, have been recently proposed to play a role in leghemoglobin protection. The occurrence of catalase and SOD activities in alfalfa (Medicago sativa L.) nodule cytosol is reported here. Enzymes were extracted at 0-4/sup 0/C from 0.5 g fresh nodules with 12 ml of a medium containing K-phosphate buffer 50 mM, pH 7.8 and Na/sub 2/EDTA 0.1 mM. The homogenate was filtered and centrifuged at 18,000 xg for 10 min, and the resulting supernatant was used for catalase assay. A further precipitation of leghemoglobin was required to avoid interferences with SOD determination. Catalase was determined by back-titration with KMnO/sub 4/. SOD was assayed by measuring the inhibition of nitro blue tetrazolium reduction. The sensitivity of SOD activity to CN/sup -/ was tested by including 1 mM KCN in the reaction mixture. Catalase activity of alfalfa nodule cytosol was 237 +/- 1 units/mg protein, decreasing very significantly (P < 0.01, Duncan's multiple range test) at 20 mM NO/sub 3//sup -/. Typical specific SOD activities were 94 +/- 5 and 65 +/- 4 units/mg protein, without CN/sup -/ and with CN/sup -/, respectively. Both activities increased very significantly at 20 mM NO/sub 3//sup -/. SOD activities with CN/sup -/ were 70-80% those without CN/sup -/ within the range of NO/sub 3//sup -/ investigated (0-20 mM).

Becana, M.; Aparicio-Tejo, P.M.; Sanchez-Diaz, M.



Catalase and superoxide dismutase activities as biomarkers of oxidative stress in workers exposed to mercury vapors  

SciTech Connect

We investigated the role of three blood antioxidant enzyme activities and total antioxidant status (TAS) as biological markers of oxidative stress in workers exposed to mercury (Hg{degrees}) vapors. Twenty-two female workers took part in the study. Blood and urine sampling for biological analyses was performed. The workers were classified into three subgroups according to their creatinine-corrected Hg concentration in urine. Blood antioxidant enzyme activities and TAS were compared between groups with nonparametric distribution-free methods. A significant difference existed in catalase activity and a slight, but not significant, difference existed in Cu{sup 2+}/Zn{sup 2+} superoxide dismutase (Cu{sup 2+}/Zn{sup 2+} SOD) activity between the three groups. No differences were observed in either the glutathione peroxidase activity or the TAS between these groups. Catalase and Cu{sup 2+}/Zn{sup 2+} SOD activities were increased in the groups of workers with higher creatinine-corrected urinary Hg concentrations when compared with the group of lower creatinine-corrected urinary Hg concentrations. Catalase activity was positively correlated with the creatinine-corrected concentration of Hg in urine, and Cu{sup 2+}/Zn{sup 2+} SOD activity was slightly correlated with the creatinine-corrected concentration of Hg in urine. The role of erythrocyte catalase and Cu{sup 2}/Zn{sup 2+} SOD activities we have measured is in agreement with the hypothesis of the involvement of reactive oxygen species production as an important event in chronic exposure to Hg{degrees} vapors in humans. In spite of the small sample size, results indicate that erythrocyte catalase and Cu{sup 2+}/Zn{sup 2+} SOD activities could be considered as markers of biological effect in workers exposed to Hg{degrees} vapors. 24 refs., 3 figs., 2 tabs.

Perrin-Nadif, R.; Dusch, M.; Mur, J.M.; Koch, C. [INRS, Vandoeuvre-les-Nancy (France)] [INRS, Vandoeuvre-les-Nancy (France); Schmitt, P. [Association InterEntreprises de Medecine du Travail du Bas-Rhin, Strasbourg (France)] [Association InterEntreprises de Medecine du Travail du Bas-Rhin, Strasbourg (France)



Role of catalase on the hypoxia/reoxygenation stress in the hypoxia-tolerant Nile tilapia.  


The specific contribution of each antioxidant enzyme to protection against the reoxygenation-associated oxidative stress after periods of hypoxia is not well understood. We assessed the physiological role of catalase during posthypoxic reoxygenation by the combination of two approaches. First, catalase activity of Nile tilapias (Oreochromis niloticus) was 90% suppressed by intraperitoneal injection of 3-amino-1,2,4-triazole (ATZ, 1g/kg). In ATZ-injected fish, liver GSH levels, oxidative stress markers, and activities of other antioxidant enzymes remained unchanged. Second, animals with depleted catalase activity (or those saline-injected) were subjected to a cycle of severe hypoxia (dissolved O(2) = 0.28 mg/l for 3 h) followed by reoxygenation (0.5 to 24 h). Hypoxia did not induce changes in the above-mentioned parameters, either in saline- or in ATZ-injected animals. Reoxygenation increased superoxide dismutase activity in saline-injected fish, whose levels were similar to ATZ-injected animals. The activities of glutathione S-transferase, selenium-dependent glutathione peroxidase, and total-GPX and the levels of GSH-eq, GSSG, and thiobarbituric acid reactive substances remained unchanged during reoxygenation in both saline- and ATZ-injected fish. The GSSG/GSH-eq ratio in ATZ-injected fish increased at 30 min of reoxygenation compared with saline-injected ones. Reoxygenation also increased carbonyl protein levels in saline-injected fish, whose levels were similar to the ATZ-injected group. Our work shows that inhibition of liver tilapia catalase causes a redox imbalance during reoxygenation, which is insufficient to induce further oxidative stress. This indicates the relevance of hepatic catalase for hypoxia/reoxygenation stress in tilapia fish. PMID:22378777

Welker, Alexis F; Campos, Elida G; Cardoso, Luciano A; Hermes-Lima, Marcelo



A novel NADPH:(bound) NADP+ reductase and NADH:(bound) NADP+ transhydrogenase function in bovine liver catalase  

PubMed Central

Many catalases have the shared property of containing bound NADPH and being susceptible to inactivation by their own substrate, H2O2. The presence of additional (unbound) NADPH effectively prevents bovine liver and human erythrocytic catalase from becoming compound II, the reversibly inactivated state of catalase, and NADP+ is known to be generated in the process. The function of the bound NADPH, which is tightly bound in bovine liver catalase, has been unknown. The present study with bovine liver catalase and [14C]NADPH and [14C]NADH revealed that unbound NADPH or NADH are substrates for an internal reductase and transhydrogenase reaction respectively; the unbound NADPH or NADH cause tightly bound NADP+ to become NADPH without becoming tightly bound themselves. This and other results provide insight into the function of tightly bound NADPH. PMID:15456401



Understanding the role of the catalase/peroxide genes in H2O2 resistance of E. coli serotype O157:H7 biofilms  

Technology Transfer Automated Retrieval System (TEKTRAN)

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...


Immunodetection of a brown planthopper (Nilaparvata lugens Stål) salivary catalase-like protein into tissues of rice, Oryza sativa.  


Saliva plays an important role in host plant-phloem-feeding insect molecular interactions. To better elucidate the role of insect saliva, a series of experiments were conducted to establish if catalase from the salivary glands of the brown planthopper (BPH; Nilaparvata lugens Stål) was secreted into rice host plant tissue during feeding. Catalase is the main enzyme that decomposes hydrogen peroxide (H2O2) at high concentrations. H2O2 is a part of the free radicals system that mediates important physiological roles including signalling and defence. Previous studies have suggested that H2O2 is involved in the rice endogenous response to BPH feeding. If, the BPH secretes catalase into host plant tissue this will counter the effects of H2O2, from detoxification to interfering with plant signalling and defence mechanisms. When BPHs were fed on a hopper-resistant rice variety for 24 h, catalase activity in the salivary glands increased 3.5-fold compared with hoppers fed on a susceptible rice variety. Further supporting evidence of the effects of BPH catalase was demonstrated by immunodetection analyses where results from two independent sources: BPH-infested rice tissue and BPH-probed artificial diets, suggest that the BPH secretes catalase-like protein during feeding. The possible physiological roles of BPH-secreted catalase are discussed. PMID:24164290

Petrova, A; Smith, C M



Mn-catalase (Alr0998) protects the photosynthetic, nitrogen-fixing cyanobacterium Anabaena PCC7120 from oxidative stress.  


Role of the non-haem, manganese catalase (Mn-catalase) in oxidative stress tolerance is unknown in cyanobacteria. The ORF alr0998 from the Anabaena PCC7120, which encodes a putative Mn-catalase, was constitutively overexpressed in Anabaena PCC7120 to generate a recombinant strain, AnKat(+). The Alr0998 protein could be immunodetected in AnKat(+) cells and zymographic analysis showed a distinct thermostable catalase activity in the cytosol of AnKat(+) cells but not in the wild-type Anabaena PCC7120. The observed catalase activity was insensitive to inhibition by azide indicating that Alr0998 protein is indeed a Mn-catalase. In response to oxidative stress, the AnKat(+) showed reduced levels of intracellular ROS which was also corroborated by decreased production of an oxidative stress-inducible 2-Cys-Prx protein. Treatment of wild-type Anabaena PCC7120 with H(2)O(2) caused (i) RNA degradation in vivo, (ii) severe reduction of photosynthetic pigments and CO(2) fixation, (iii) fragmentation and lysis of filaments and (iv) loss of viability. In contrast, the AnKat(+) strain was protected from all the aforesaid deleterious effect under oxidative stress. This is the first report on protection of an organism from oxidative stress by overexpression of a Mn-catalase. PMID:22897147

Banerjee, Manisha; Ballal, Anand; Apte, Shree Kumar



Screening of bacterial isolates from polluted soils exhibiting catalase and peroxidase activity and diversity of their responses to oxidative stress.  


For the survival of individual isolates of gram-negative bacteria Pseudomonas putida, Achromobacter xylosoxidans, and the gram-positive bacterium Bacillus megaterium, in an environment polluted with crude oil products, the production of catalases exhibiting both catalase and dianisidine-peroxidase activity is important. Electrophoretic resolution of cell-free extracts of aerobically grown strains in Luria-Bertani medium during exponential phase revealed distinctive expression of catalatic and peroxidatic activities detected with 3,3'-diaminobenzidine tetrahydrochloride. A considerable diversity in microbial catalase and peroxidase responses to 20 or 40 mM H(2)O(2) stress, resulted from hydroperoxidase's variant of original isolates, indicating an environmental selective pressure. However, catalase was important for the adaptation of cultures to high concentration of 60 mM H(2)O(2). Appreciable differences in the sensitivity to toxic effect of H(2)O(2) (20 or 40 mM) treatment between individual isolates and their adapted variants during growth were observed until the middle of exponential phase, but they were insignificant at the entry to stationary phase. Isolates also exhibited a considerable diversity in catalases responses to phenolic contaminants 1 and 2 mM o- or p-phenylenediamine. Catalase activity of bacterium P. putida was visibly stimulated only by p-phenylenediamine and not by its positional isomer o-PDA. This study contributes to a better understanding of the role catalases play in bacterial responses to a polluted environment. PMID:20145932

Bucková, Mária; Godocíková, Jana; Zámocký, Marcel; Polek, Bystrík



Synergistic roles of Helicobacter pylori methionine sulfoxide reductase and GroEL in repairing oxidant-damaged catalase.  


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

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



Production of catalase and glucose oxidase by Aspergillus niger using unconventional oxygenation of culture.  


A novel method for increasing dissolved oxygen concentration in culture media has been developed. It involves adding hydrogen peroxide (H2O2) to the medium which is then decomposed to oxygen and water by catalase. Some factors affecting oxygenation of culture were investigated. Maximal oxygen concentration occurred in 50 ml of the medium containing 0-2 g wet mycelium and 0.2% glucose at pH 5.0. A new apparatus for automated addition of H2O2 to the bioreactor to keep the dissolved oxygen concentration constant over the range 1-100% +/- 2% was tested. A significant increase (over sixfold) of intracellular catalase activity was obtained while the dissolved oxygen concentration remained stable (30% +/- 2%). PMID:10945783

Fiedurek, J; Gromada, A




PubMed Central

Cells contain a large number of antioxidants to prevent or repair the damage caused by ROS, as well as to regulate redox-sensitive signaling pathways General protocols are described to measure the antioxidant enzyme activity of superoxide dismutase (SOD), catalase, and glutathione peroxidase. The SODs convert superoxide radical into hydrogen peroxide and molecular oxygen, while the catalase and peroxidases convert hydrogen peroxide into water. In this way, two toxic species, superoxide radical and hydrogen peroxide, are converted to the harmless product water. Western blots, activity gels and activity assays are various methods used to determine protein and activity in both cells and tissue depending on the amount of protein needed for each assay. Other techniques including immunohistochemistry and immunogold can further evaluate the levels of the various antioxidant enzymes in tissue and cells. In general, these assays require 24 to 48 hours to complete. PMID:20057381

Weydert, Christine J.; Cullen, Joseph J.



Regulation of the oxidative stress protective enzymes, catalase and superoxide dismutase in Xanthomonas--a review.  


Xanthomonas showed atypical regulation of catalase (Kat) and superoxide dismutase with respect to growth phase and response to various inducers. The highest levels of both enzymes were detected during early log phase of growth and declined as growth continued. This was in contrast to resistance levels to superoxides, H2O2 and organic peroxides, which reached maximum levels during stationary phase. Xanthomonas catalase was induced over six fold by superoxide generators and methyl methane sulfonate but weakly by H2O2. The regulation pattern of these enzymes could be important during plant/microbe interactions. To facilitate elucidation of Xanthomonas kat gene regulation, highly conserved regions of monofuctional Kat amino acid sequences were used to synthesize oligodeoxyribonucleotide primers for use in PCR reactions with Xanthomonas genomic DNA as templates. The Xanthomonas-specific PCR kat probe was used to isolate a functional kat from Xanthomonas campestris pv. phaseoli. PMID:8955626

Loprasert, S; Vattanaviboon, P; Praituan, W; Chamnongpol, S; Mongkolsuk, S



Developmental changes of erythrocyte catalase activity in rats exposed to acute hypoxia.  


The erythrocytes represent an important source of antioxidant capacity of the blood. Catalase (EC is one of the enzymatic components of their antioxidant defense system. The objective of this study was to follow erythrocyte catalase (CAT) in 7-, 15-, 21-, 35-, 60- and 90-day-old Wistar rats of both sexes in normoxia and after exposure to intensive acute hypobaric hypoxia. During the development CAT activity increases in both sexes, but the rise was usually higher in females. Hypobaric hypoxia increased CAT activity in all studied age groups of both sexes. However, higher CAT activity in females was less affected by hypoxia than the lower activity in males. This was true for nearly all age groups studied. It can be concluded that both ontogenetic aspects and sex differences play a major role in establishing the activity of CAT, which is an important part of the antioxidant defense of the organism. PMID:15641929

Rauchová, H; Vokurková, M; Koudelová, J



The Monofunctional Catalase KatE of Xanthomonas axonopodis pv. citri Is Required for Full Virulence in Citrus Plants  

PubMed Central

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 H2O2 concentrations. In addition, Xac exhibited an adaptive response to hydrogen peroxide, displaying higher levels of catalase activity and H2O2 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 H2O2. 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 KatE has been shown to have an important function for the colonization and survival of the bacterium in the citrus plant during the pathogenic process. Our work provides the first genetic evidence to support a monofunctional catalase as a virulence factor in Xac. PMID:20520822

Tondo, María Laura; Petrocelli, Silvana; Ottado, Jorgelina; Orellano, Elena G.



Adenovirus-mediated catalase gene transfer reduces oxidant stress in human, porcine and rat pancreatic islets  

Microsoft Academic Search

Summary   Susceptibility of pancreatic islets to oxidant stress may affect islet viability and contribute to primary non function of\\u000a allo- or xenogenic grafts. We investigated the influence of overexpression of catalase (CAT) on the viability of human, porcine\\u000a and rat islets, as well as INS-1 beta-cell line. Islets were transfected with a replication-deficient adenovirus vector containing\\u000a human CAT cDNA under

P. Y. Benhamou; C. Moriscot; M. J. Richard; O. Beatrix; L. Badet; F. Pattou; J. Kerr-Conte; J. Chroboczek; P. Lemarchand; S. Halimi



The study of ascorbate peroxidase, catalase and peroxidase during in vitro regeneration of Argyrolobium roseum.  


Here, we demonstrate the micropropagation protocol of Argyrolobium roseum (Camb.), an endangered herb exhibiting anti-diabetic and immune-suppressant properties, and antioxidant enzymes pattern is evaluated. Maximum callogenic response (60 %) was observed from leaf explant at 1.0 mg L(-1) 1-nephthalene acetic acid (NAA) and 0.5 mg L(-1) 6-benzyl aminopurine (BA) in Murashige and Skoog (MS) medium using hypocotyl and root explants (48 % each). Addition of AgNO3 and PVP in the culture medium led to an increase in callogenic response up to 86 % from leaf explant and 72 % from hypocotyl and root explants. The best shooting response was observed in the presence of NAA, while maximum shoot length and number of shoots were achieved based on BA-supplemented MS medium. The regenerated shoots were rooted and successfully acclimatized under greenhouse conditions. Catalase and peroxidase enzymes showed ascending pattern during in vitro plant development from seed while ascorbate peroxidase showed descending pattern. Totally reverse response of these enzymes was observed during callus induction from three different explants. During shoot induction, catalase and peroxidase increased at high rate while there was a mild reduction in ascorbate peroxidase activity. Catalase and peroxidase continuously increased; on the other hand, ascorbate peroxidase activity decreased during root development and acclimatization states. The protocol described here can be employed for the mass propagation and genetic transformation of this rare herb. This study also highlights the importance and role of ascorbate peroxidase, catalase, and peroxidase in the establishment of A. roseum in vitro culture through callogenesis and organogenesis. PMID:24142360

Habib, Darima; Chaudhary, Muhammad Fayyaz; Zia, Muhammad



Glutathione, Glutathione-Related Enzymes, and Catalase Activities in the Earthworm Eisenia fetida andrei  

Microsoft Academic Search

.   The aim of this work was to provide basic data on the antioxidant defences in the annelid Eisenia fetida andrei (E. f. a.). Methods for measurement of three antioxidant enzymes—catalase (CAT), glutathione peroxidase (GPX), and glutathione\\u000a reductase (GR)—and of glutathione-S-transferase (GST) were optimized. GPX activity differed according to the substrate used:\\u000a cumene hydroperoxide (CUOOH) or hydrogen peroxide (H2O2). The

M. Saint-Denis; F. Labrot; J. F. Narbonne; D. Ribera



Ergot cluster-encoded catalase is required for synthesis of chanoclavine-I in Aspergillus fumigatus.  


Genes required for ergot alkaloid biosynthesis are clustered in the genomes of several fungi. Several conserved ergot cluster genes have been hypothesized, and in some cases demonstrated, to encode early steps of the pathway shared among fungi that ultimately make different ergot alkaloid end products. The deduced amino acid sequence of one of these conserved genes (easC) indicates a catalase as the product, but a role for a catalase in the ergot alkaloid pathway has not been established. We disrupted easC of Aspergillus fumigatus by homologous recombination with a truncated copy of that gene. The resulting mutant (?easC) failed to produce the ergot alkaloids typically observed in A. fumigatus, including chanoclavine-I, festuclavine, and fumigaclavines B, A, and C. The ?easC mutant instead accumulated N-methyl-4-dimethylallyltryptophan (N-Me-DMAT), an intermediate recently shown to accumulate in Claviceps purpurea strains mutated at ccsA (called easE in A. fumigatus) (Lorenz et al. Appl Environ Microbiol 76:1822-1830, 2010). A ?easE disruption mutant of A. fumigatus also failed to accumulate chanoclavine-I and downstream ergot alkaloids and, instead, accumulated N-Me-DMAT. Feeding chanoclavine-I to the ?easC mutant restored ergot alkaloid production. Complementation of either ?easC or ?easE mutants with the respective wild-type allele also restored ergot alkaloid production. The easC gene was expressed in Escherichia coli, and the protein product displayed in vitro catalase activity with H(2)O(2) but did not act, in isolation, on N-Me-DMAT as substrate. The data indicate that the products of both easC (catalase) and easE (FAD-dependent oxidoreductase) are required for conversion of N-Me-DMAT to chanoclavine-I. PMID:21409592

Goetz, Kerry E; Coyle, Christine M; Cheng, Johnathan Z; O'Connor, Sarah E; Panaccione, Daniel G



A structural and dynamic investigation of the inhibition of catalase by nitric oxide.  


Determining the chemical and structural modifications occurring within a protein during fundamental processes such as ligand or substrate binding is essential to building up a complete picture of biological function. Currently, significant unanswered questions relate to the way in which protein structural dynamics fit within the structure-function relationship and to the functional role, if any, of bound water molecules in the active site. Addressing these questions requires a multidisciplinary approach and complementary experimental techniques that, in combination, enhance our understanding of the complexities of protein chemistry. We exemplify this philosophy by applying both physical and biological approaches to investigate the active site chemistry that contributes to the inhibition of the Corynebacterium glutamicum catalase enzyme by nitric oxide. Ultrafast two-dimensional infrared spectroscopy (2D-IR) experiments exploit the NO ligand as a local probe of the active site molecular environment and shows that catalase displays a dynamically-restricted, 'tight,' structure. X-ray crystallography studies of C. glutamicum catalase confirm the presence of a conserved chain of hydrogen-bonded bound water molecules that link the NO ligand and the protein scaffold. This combination of bound water and restricted dynamics stands in stark contrast to other haem proteins, such as myoglobin, that exhibit ligand transport functionality despite the presence of a similar distal architecture in close proximity to the ligand. We conclude not only that the bound water molecules in the catalase active site play an important role in molecular recognition of NO but also may be part of the mechanistic operation of this important enzyme. PMID:24121528

Candelaresi, Marco; Gumiero, Andrea; Adamczyk, Katrin; Robb, Kirsty; Bellota-Antón, César; Sangal, Vartul; Munnoch, John; Greetham, Gregory M; Towrie, Michael; Hoskisson, Paul A; Parker, Anthony W; Tucker, Nicholas P; Walsh, Martin A; Hunt, Neil T



Thermotolerant Campylobacter with no or weak catalase activity isolated from dogs  

Microsoft Academic Search

ThermotolerantCampylobacter strains isolated from dog feces were characterized by phenotypical tests, DNA base composition, and DNA-DNA-hybridization. Out of 98 strains, 63 were catalase negative or weakly reacting (CNW); they were found in diarrheic as well as in healthy dogs. The CNW strains were all nalidixic-acid sensitive, hippurate negative, and grew at 42°C but not at 25°C. Seven strains were further

Karin Sandstedt; Jan Ursing; Mats Walder



Complete Nucleotide Sequence of cDNA and Deduced Amino Acid Sequence of Rat Liver Catalase  

Microsoft Academic Search

We have isolated five cDNA clones for rat liver catalase (hydrogen peroxide: hydrogen peroxide oxidoreductase, EC These clones overlapped with each other and covered the entire length of the mRNA, which had been estimated to be 2.4 kilobases long by blot hybridization analysis of electrophoretically fractionated RNA. Nucleotide sequencing was carried out on these five clones and the composite

Shuichi Furuta; Hiroaki Hayashi; Makoto Hijikata; Shoko Miyazawa; Takashi Osumi; Takashi Hashimoto



Extension of Life-Span with Superoxide Dismutase\\/Catalase Mimetics  

Microsoft Academic Search

We tested the theory that reactive oxygen species cause aging. We augmented the natural antioxidant systems of Caenorhabditis elegans with small synthetic superoxide dismutase\\/catalase mimetics. Treatment of wild-type worms increased their mean life-span by a mean of 44 percent, and treatment of prematurely aging worms resulted in normalization of their life-span (a 67 percent increase). It appears that oxidative stress

Simon Melov; Joanne Ravenscroft; Sarwatt Malik; Matt S. Gill; David W. Walker; Peter E. Clayton; Douglas C. Wallace; Bernard Malfroy; Susan R. Doctrow; Gordon J. Lithgow



Hydrogen Peroxide Formation and Catalase Activity in the Lactic Acid Bacteria  

Microsoft Academic Search

SUMMARY Some lactic acid bacteria formed detectable H202 and some did not, regardless of their preference or requirement for aerobic or anaerobic conditions. Whether or not H202 was formed depended in some instances on the substrate used as energy source. Two H202-splitting activities were encountered though never in the same organism. One, named pseudo- catalase activity, was insensitive to 0.01

R. Whittenbury



Compounds I of Catalase and Horse Radish Peroxidase: pi -cation Radicals  

Microsoft Academic Search

Two-electron oxidation of cobaltous octa-ethylporphyrin [Co(II)(Et)8P] yields a stable pi -cation radical [Co(III)(Et)8P]2+\\\\cdot, the optical spectrum of which exhibits spectral changes dependent upon the nature of the counterion. Comparison of these spectra with those of Compounds I of horseradish peroxidase and catalase leads us to propose that these Compounds I contain a pi -cation radical of the heme prosthetic group.

D. Dolphin; A. Forman; D. C. Borg; J. Fajer; R. H. Felton



Immobilization of catalase onto chitosan and cibacron blue F3GA attached chitosan beads  

Microsoft Academic Search

In this study, chitosan beads (Ch-bead) and cibacron blue F3GA attached chitosan beads (CB-Ch-bead) were prepared. Their characteristics were investigated with experiments of swelling, thermogravimetric analysis and Fourier transform infrared (FTIR) spectroscopic analysis. Catalase (CAT) was immobilized onto these beads. The adsorption isotherms have a Langmuirian shape for Ch-beads and CB-Ch-beads. The CAT adsorption capacity of Ch-beads is higher than

?enay Akku? Çetinus; H. Nursevin Öztop; Dursun Sarayd?n



Human catalase gene polymorphism (CAT C-262T) and risk of male infertility.  


Infertility is the failure of a couple to engender after endeavouring at least one full year of unprotected intercourse. It has been reported that reactive oxygen species contributed to pathogenesis of various disease. To inactivate ROS cells biosynthesise several antioxidant enzymes, one of them is catalase which contributes H2 O2 to H2 O and O2 . This study set out to delineate the association of catalase C-262T polymorphism with idiopathic male infertility. The study included 195 men with idiopathic infertility and 190 healthy volunteers. Genomic DNA was extracted from peripheral blood leucocytes. Genotype and allele frequencies were determined in patients and controls using allele-specific PCR (AS-PCR). The prevalence of genotype frequencies of the CAT CC/CT/TT was 31.79%, 65.12% and 3.07%, respectively, in infertile subjects, as against 24.73%, 55.26% and 20%, respectively, in healthy volunteers. Statistical analysis has emerged significant difference from the comparison of either genotype (P < 0.05). Taking into accounts of results, the catalase C-262T polymorphism indicates that CAT-262T/T genotype confers less susceptibility to male infertility. Further studies with larger numbers of patients are required for further evaluation and confirmation of our finding. PMID:24456074

Sabouhi, S; Salehi, Z; Bahadori, M H; Mahdavi, M



Catalase-like activity of horseradish peroxidase: relationship to enzyme inactivation by H2O2.  

PubMed Central

H2O2 is the usual oxidizing substrate of horseradish peroxidase C (HRP-C). In the absence in the reaction medium of a one-electron donor substrate, H2O2 is able to act as both oxidizing and reducing substrate. However, under these conditions the enzyme also undergoes a progressive loss of activity. There are several pathways that maintain the activity of the enzyme by recovering the ferric form, one of which is the decomposition of H2O2 to molecular oxygen in a similar way to the action of catalase. This production of oxygen has been kinetically characterized with a Clark-type electrode coupled to an oxygraph. HRP-C exhibits a weak catalase-like activity, the initial reaction rate of which is hyperbolically dependent on the H2O2 concentration, with values for K(2) (affinity of the first intermediate, compound I, for H2O2) and k(3) (apparent rate constant controlling catalase activity) of 4.0 +/- 0.6 mM and 1.78 +/- 0.12 s(-1) respectively. Oxygen production by HRP-C is favoured at pH values greater than approx. 6.5; under similar conditions HRP-C is also much less sensitive to inactivation during incubations with H2O2. We therefore suggest that this pathway is a major protective mechanism of HRP-C against such inactivation. PMID:11171085

Hernández-Ruiz, J; Arnao, M B; Hiner, A N; García-Cánovas, F; Acosta, M



Purification and characterization of recombinant catalase-peroxidase, which confers isoniazid sensitivity in Mycobacterium tuberculosis.  


The Mycobacterium tuberculosis katG gene encodes a dual-function enzyme called catalase-peroxidase, which confers sensitivity in M. tuberculosis to isonicotinic acid hydrazide. We have constructed a system for the high level expression of a recombinant form of this enzyme by amplifying the katG gene from the pYZ56 construct (1) and subcloning into a vector suitable for expression in Escherichia coli. The resulting plasmid, pTBCP, produced the catalase-peroxidase in large quantities, corresponding to 30% of total cell protein. The enzyme has been purified to homogeneity and appears to be a dimer in the native form. Using either hydrogen peroxide or t-butyl hydroperoxide and 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) as substrates, kcat and Km values have been obtained for both catalatic and peroxidatic activities, respectively. The availability of significant quantities of an active, folded, recombinant form of M. tuberculosis catalase-peroxidase should thus facilitate future studies of its role in drug activation and antibiotic resistance. PMID:9395452

Nagy, J M; Cass, A E; Brown, K A



katGI and katGII encode two different catalases-peroxidases in Mycobacterium fortuitum.  


It has been suggested that catalase-peroxidase plays an important role in several aspects of mycobacterial metabolism and is a virulence factor in the main pathogenic mycobacteria. In this investigation, we studied genes encoding for this protein in the fast-growing opportunistic pathogen Mycobacterium fortuitum. Nucleotide sequences of two different catalase-peroxidase genes (katGI and katGII) of M. fortuitum are described. They show only 64% homology at the nucleotide level and 55% identity at the amino acid level, and they are more similar to catalases-peroxidases from different bacteria, including mycobacteria, than to each other. Both proteins were found to be expressed in actively growing M. fortuitum, and both could also be expressed when transformed into Escherichia coli and M. aurum. We detected the presence of a copy of IS6100 in the neighboring region of a katG gene in the M. fortuitum strain in which this element was identified (strain FC1). The influence of each katG gene on isoniazid (isonicotinic acid hydrazide; INH) susceptibility of mycobacteria was checked by using the INH-sensitive M. aurum as the host. Resistance to INH was induced when katGI was transformed into INH-sensitive M. aurum, suggesting that this enzyme contributes to the natural resistance of M. fortuitum to the drug. This is the first report showing two different genes encoding same enzyme activity which are actively expressed within the same mycobacterial strain. PMID:9371430

Menéndez, M C; Ainsa, J A; Martín, C; García, M J



Superoxide dismutase and catalase conjugated to polyethylene glycol increases endothelial enzyme activity and oxidant resistance  

SciTech Connect

Covalent conjugation of superoxide dismutase and catalase with polyethylene glycol (PEG) increases the circulatory half-lives of these enzymes from <10 min to 40 h, reduced immunogenicity, and decreases sensitivity to proteolysis. Because PEG has surface active properties and can induce cell fusion, the authors hypothesized that PEG conjugation could enhance cell binding and association of normally membrane-impermeable enzymes. Incubation of cultured porcine aortic endothelial cells with /sup 125/I-PEG-catalase or /sup 125/I-PEG-superoxide dismutase produced a linear, concentration-dependent increase in cellular enzyme activity and radioactivity. Fluorescently labeled PEG-superoxide dismutase incubated with endothelial cells showed a vesicular localization. Mechanical injury to cell monolayers, which is known to stimulate endocytosis, further increased the uptake of fluorescent PEG-superoxide dismutase. Addition of PEG and PEG-conjugated enzymes perturbed the spin-label binding environment, indicative of producing an increase in plasma membrane fluidity. Thus, PEG conjugation to superoxide dismutase and catalase enhances cell association of these enzymes in a manner which increases cellular enzyme activities and provides prolonged protection from partially reduced oxygen species.

Beckman, J.S.; Minor, R.L. Jr.; White, C.W.; Repine, J.E.; Rosen, G.M.; Freeman, B.A.



On the role of catalase in the oxidation of tissue fatty acids  

SciTech Connect

The role of catalase in lipid metabolism has been studied by means of a comparison of the turnover characteristics of the major lipid classes in the normal mouse with those of animals in which the catalase activity had been inhibited and blocked by aminotriazole and allylisopropylacetamide. Double isotope ratios were determined in the lipid fractions of several tissues following the injection of labeled glycerol, and a number of significant differences were identified between these treatments. Since catalase is recognized as an integral component of the peroxisomal pathway of fatty acid oxidation, these results may be taken as indicating that interruption of the process of peroxisomal beta-oxidation in this manner cause extensive perturbations of lipid metabolism in the living animal, and these perturbations extend well beyond those tissues where the predominant localization of these organelles occurs. The concept which derives from these data--that of a significant regulatory role of peroxisomes in relation to the overall balance of lipid metabolism in the animal body--is described and discussed.

Crane, D.; Masters, C.



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

SciTech Connect

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.

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



How Does Catalase Release Nitric Oxide? A Computational Structure Activity Relationship Study  

PubMed Central

Hydroxyurea (HU) is the only FDA approved medication for treating sickle cell disease in adults. The primary mechanism of action is pharmacological elevation of nitric oxide (NO) levels which induces propagation of fetal hemoglobin. HU is known to undergo redox reactions with heme based enzymes like hemoglobin and catalase to produce NO. However, specific details about the HU based NO release remain unknown. Experimental studies indicate that interaction of HU with human catalase compound I produces NO. Presently, we combine flexible receptor-flexible substrate induced fit docking (IFD) with energy decomposition analyses to examine the atomic level details of a possible key step in the clinical conversion of HU to NO. Substrate binding modes of nine HU analogs with catalase compound I were investigated to determine the essential properties necessary for effective NO release. Three major binding orientations were found that provide insight into the possible reaction mechanisms for producing NO. Further results show that anion/radical intermediates produced as part of these mechanisms would be stabilized by hydrogen bonding interactions from distal residues His75, Asn148, Gln168, and oxoferryl-heme. These details will ideally contribute to both a clearer mechanistic picture and provide insights for future structure based drug design efforts. PMID:24087936

Vankayala, Sai Lakshmana; Hargis, Jacqueline C.; Woodcock, H. Lee



How catalase recognizes H?O? in a sea of water.  


Monofunctional heme-catalases have been studied for many decades but there is still an incomplete understanding of why such a large tetrameric protein with deeply buried active sites is required to accomplish such a simple reaction as H2 O2 dismutation. Catalase accomplishes this reaction at a high rate although water at 55 M is expected to compete with H2 O2 for the enzyme's active site. Using molecular dynamics simulations we addressed the question as to how catalase selects H2 O2 in water. Selection is accomplished through different mechanisms: higher residence time of H2 O2 in the vicinity of certain prevalent amino acid residues at the protein surface and substrate channel, coordinated motion of the main passage amino acids that is increased in the presence of H2 O2 , a gate valve mechanism consisting of the motion of two contiguous phenylalanine residues that drive water molecules out of the final section of the substrate channel, a hydrophobic barrier before the active site that was crossed more easily by H2 O2 which kept most of its hydrogen bonds while passing, and finally an increased residence time for H2 O2 at the active site. These mechanisms, based on the physicochemical differences between H2 O2 and water, provide an explanation as to why such a large tetrameric protein with deeply buried active sites is required to accomplish efficient H2 O2 dismutation. PMID:23818262

Domínguez, Laura; Sosa-Peinado, Alejandro; Hansberg, Wilhelm



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*  

PubMed Central

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

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



Nucleotide diversity and gene expression of Catalase and Glutathione peroxidase in irradiated Scots pine (Pinus sylvestris L.) from the Chernobyl exclusion zone.  


In the Chernobyl exclusion zone forest trees have to tolerate and to adapt to ionizing radiation, therefore the molecular basis of their adaptive responses is of the utmost interest. Based on SNP analysis and real time PCR nucleotide diversity and expression profiles of gene fragments of catalase (Cat) and glutathione peroxidase (GPx), which are known as radical scavenging genes, were analysed in the needles of irradiated pine trees of the Chernobyl exclusion zone. In acutely and chronically irradiated trees (50 years old) planted before the accident a higher nucleotide diversity of Cat and more somatic mutations were found compared to their control. Chronically irradiated trees (20 years old) planted after the accident showed a similar nucleotide diversity of Cat compared to their control and in both collectives one somatic mutation was found. The nucleotide diversity of GPx was higher in all analysed trees compared to Cat. No somatic mutation events were found in GPx. For both gene fragments, no association between the received dose in a tree and the nucleotide diversity and mutation events was detected. The expression profiles of Cat and GPx in acutely and chronically and in chronically irradiated trees were similar. Compared to their corresponding control collectives, Cat was up-regulated and GPx slightly down-regulated. PMID:22304996

Vornam, Barbara; Arkhipov, Andrey; Finkeldey, Reiner



Catalase activity in macro- and microorganisms as an indicator of biotic stress in coastal waters of the eastern Mediterranean Sea  

Microsoft Academic Search

In this study we examined the activity of catalase in the water column (mainly attributed to planktonic microorganisms) and\\u000a the activity of catalase and superoxide dismutase (SOD), as well as lipid peroxidation in the midgut gland of the benthic\\u000a bivalve Donax trunculus as possible indicators of biotic stress. The measurements were performed at stations situated at known contaminated and clean

D. L. Angel; U. Fiedler; N. Eden; N. Kress; D. Adelung; B. Herut



Active and inhibited human catalase structures: ligand and NADPH binding and catalytic mechanism 1 1 Edited by R. Huber  

Microsoft Academic Search

Human catalase is an heme-containing peroxisomal enzyme that breaks down hydrogen peroxide to water and oxygen; it is implicated in ethanol metabolism, inflammation, apoptosis, aging and cancer. The 1.5 Å resolution human enzyme structure, both with and without bound NADPH, establishes the conserved features of mammalian catalase fold and assembly, implicates Tyr370 as the tyrosine radical, suggests the structural basis

Christopher D Putnam; Andrew S Arvai; Yves Bourne; John A Tainer



Changes in the activities of catalase, peroxidase, and polyphenol oxidase in apple buds during bud break induced by thidiazuron  

Microsoft Academic Search

The breaking of dormancy in apple buds (Malus domestica Borkh cv. York Imperial) by thidiazuron (N-phenyl-N?-1,2,3,-thidiazol-5-ylurea) was investigated in relation to catalase, peroxidase, and polyphenol oxidase activities and their\\u000a isoenzyme patterns. The activity and number of isoenzymic components of catalase increased progressively during bud break,\\u000a then decreased after buds started to grow. Peroxidase activity was highest during dormancy and declined

Shiow Y. Wang; Hong J. Jiao; Miklos Faust



Catalase potentiates retinoic acid-induced THP1 monocyte differentiation into macrophage through inhibition of peroxisome proliferator-activated receptor  

Microsoft Academic Search

Macrophage differentiation plays a piv- otal role in cardiovascular diseases and many other physiological processes. However, the role of re- action oxygen species in macrophage differentia- tion has not been elucidated. Here, we report func- tional characterization of catalase, an enzyme that degrades hydrogen peroxide (H2O2), in THP-1 monocyte differentiation. Treatment of THP-1 cells with catalase was able to synergize

Qiurong Ding; Ting Jin; Zhenzhen Wang; Yan Chen



Investigating catalase activity through hydrogen peroxide decomposition by bacteria biofilms in real time using scanning electrochemical microscopy.  


Catalase activity through hydrogen peroxide decomposition in a 1 mM bulk solution above Vibrio fischeri (?-Protebacteria-Vibrionaceae) bacterial biofilms of either symbiotic or free-living strains was studied in real time by scanning electrochemical microscopy (SECM). The catalase activity, in units of micromoles hydrogen peroxide decomposed per minute over a period of 348 s, was found to vary with incubation time of each biofilm in correlation with the corresponding growth curve of bacteria in liquid culture. Average catalase activity for the same incubation times ranging from 1 to 12 h was found to be 0.28 ± 0.07 ?mol H2O2/min for the symbiotic biofilms and 0.31 ± 0.07 ?mol H2O2/min for the free-living biofilms, suggesting similar catalase activity. Calculations based on Comsol Multiphysics simulations in fitting experimental biofilm data indicated that approximately (3 ± 1) × 10(6) molecules of hydrogen peroxide were decomposed by a single bacterium per second, signifying the presence of a highly active catalase. A 2-fold enhancement in catalase activity was found for both free-living and symbiotic biofilms in response to external hydrogen peroxide concentrations as low as 1 nM in the growth media, implying a similar mechanism in responding to oxidative stress. PMID:24328342

Abucayon, Erwin; Ke, Neng; Cornut, Renaud; Patelunas, Anthony; Miller, Douglas; Nishiguchi, Michele K; Zoski, Cynthia G



Expression and purification of soluble bio-active rice plant catalase-A from recombinant Escherichia coli.  


Catalase in plants is a heme-coordinated tetrameric protein that primarily disproportionates hydrogen peroxide into water and oxygen. It plays an important role in maintaining cellular concentration of hydrogen peroxide to a level, necessary for all aspects of normal plant growth and development. Except for its recombinant expression in transgenic plants and insect cell line, the protein is yet to be synthesized in its bio-active form in prokaryotic expression system. Attempts made in past for recombinant expression of plant catalase in Escherichia coli consistently resulted in formation of insoluble and inactive aggregates of inclusion body. Here we have shown the specific requirement of a thioredoxin fusion partner, the involvement of trigger factor protein and the low temperature treatment during induction period for synthesis of completely solubilized rice plant catalase-A in recombinant E. coli. Furthermore, the bacteria required the supplementation of ?-aminolevulinic acid to produce bio-active recombinant rice catalase-A. The molecular and biochemical properties of the purified recombinant protein showed the characteristic features of a typical mono-functional plant catalase. These results attest to the usefulness of the present protocol for production of plant catalase using E. coli as heterologous expression system. PMID:21978604

Ray, Mamata; Mishra, Panchanand; Das, Priyanka; Sabat, Surendra Chandra



Catalase has a novel protective role against electrophile killing of Xanthomonas.  


The ability of XANTHOMONAS: campestris pv. phaseoli to protect itself against lethal concentrations of man-made (N:-ethylmaleimide, NEM) and endogenously produced (methylglyoxal, MG) electrophiles was investigated. Pretreatment of X. c. pv. phaseoli with a low concentration of NEM induced protection against lethal concentrations of NEM and MG. MG pretreatment weakly induced protection against NEM but not against MG itself. NEM-induced protection against electrophile killing required new protein synthesis and was abolished by the addition of a protein synthesis inhibitor. By contrast, MG-induced protection against NEM killing was independent of de novo protein synthesis. X. c. pv. phaseoli harbouring an expression vector carrying a catalase gene was over 100-fold more resistant to MG and NEM killing. High expression levels of genes for other peroxide-protective enzymes, such as those for alkyl hydroperoxide reductase (ahpC and ahpF) and ohr, failed to protect against electrophile killing. Thus, catalase appears to have a novel protective role(s) against electrophile toxicity. This finding suggests that in X. c. pv. phaseoli NEM and MG toxicity might involve accumulation and/or increased production of H(2)O(2). This idea was supported by the observation that addition of 10 mM sodium pyruvate, a compound that can react chemically with peroxide or hydroxyl radical scavengers (DMSO and glycerol), was found to protect XANTHOMONAS: from electrophile killing. The protective role of catalase and the role of H(2)O(2) in electrophile toxicity are novel observations and could be generally important in other bacteria. In addition, unlike other bacteria, XANTHOMONAS: in stationary phase was more susceptible to electrophile killing compared to cells in exponential phase. PMID:11158366

Vattanaviboon, P; Sriprang, R; Mongkolsuk, S



X-ray diffraction study of Penicillium Vitale catalase in the complex with aminotriazole  

SciTech Connect

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.

Borovik, A. A.; Grebenko, A. I.; Melik-Adamyan, V. R., E-mail: [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)



X-ray diffraction study of Penicillium Vitale catalase in the complex with aminotriazole  

NASA Astrophysics Data System (ADS)

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.

Borovik, A. A.; Grebenko, A. I.; Melik-Adamyan, V. R.



Dynamics of the reaction glucose-catalase-glucose oxidase-hydrogen peroxide  

NASA Astrophysics Data System (ADS)

Glucose-catalase-glucose oxidase-hydrogen peroxide reaction is one of the few known enzymatic systems studied in vitro in the field of nonlinear chemical dynamics. This reaction belongs to the family of oscillatory enzymatic reactions, which form a natural basis of oscillations in biological systems. A parametric study of dependence on mixing, temperature and initial concentrations of components in a batch stirred reactor was carried out. A newly proposed mathematical model of the reaction conforms to the obtained experimental data. Results of our experiments and simulations hint at further directions of research of non-linear dynamics in this reaction.

?íp, M.; Schreiberová, L.; Schreiber, I.



Draft genomic DNA sequence of strain Halomonas sp. FS-N4 exhibiting high catalase activity.  


Halomonas sp. FS-N4 is a bacterium, which can grow in the medium Marine Broth 2216 with 5M initial hydrogen peroxide concentration, shows a strong oxidation resistance, and the crude enzyme activity can reach as high as 13.33katal/mg. We reported the draft genome sequence of H. sp. FS-N4, showing that it contains 3434 protein-coding genes, including the genes putatively involved in the response to the oxidative stress, among which a phytochrome-like gene might be a key point to survive in the environment with high concentration of hydrogen peroxide and exhibit high catalase activity. PMID:25176559

Pan, Jie; Abulaizi, Ailiman; Sun, Cong; Cheng, Hong; Wu, Min



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


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 20weeks 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 Ca(2+) 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 ?(IKK?), 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 IKK?, 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 IKK?-AMPK-dependent restoration of myocardial autophagy. This article is part of a Special Issue entitled: Autophagy and protein quality control in cardiometabolic diseases. PMID:24993069

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



Genetic polymorphisms in catalase and CYP1B1 determine DNA adduct formation by benzo(a)pyrene ex vivo.  


Genetic polymorphisms can partially explain the large inter-individual variation in DNA adduct levels following exposure to polycyclic aromatic hydrocarbons. Effects of genetic polymorphisms on DNA adduct formation are difficult to assess in human studies because exposure misclassification attenuates underlying relationships. Conversely, ex vivo studies offer the advantage of controlled exposure settings, allowing the possibility to better elucidate genotype-phenotype relationships and gene-gene interactions. Therefore, we exposed lymphocytes of 168 non-smoking volunteers ex vivo to the environmental pollutant benzo(a)pyrene (BaP) and BaP-related DNA adducts were quantified. Thirty-four genetic polymorphisms were assessed in genes involved in carcinogen metabolism, oxidative stress and DNA repair. Polymorphisms in catalase (CAT, rs1001179) and cytochrome P450 1B1 (CYP1B1, rs1800440) were significantly associated with DNA adduct levels, especially when combined. Moreover, reverse transcription-polymerase chain reaction (RT-PCR) analysis in a subset of 30 subjects revealed that expression of catalase correlated strongly with expression of CYP1B1 (R = 0.92, P < 0.001). To further investigate the mechanism by which catalase influences CYP1B1 and how they simultaneously affect BaP-related DNA adduct levels, catalase expression was transiently knocked down in the human lung epithelial cell line A549. Although catalase knockdown did not immediately change CYP1B1 gene expression, recovery of catalase expression 8 h after the knockdown coincided with a 2.2-fold increased expression of CYP1B1 (P < 0.05). We conclude that the genetic polymorphism in the promoter region of CAT may determine the amount and activity of catalase, which may subsequently regulate the expression of CYP1B1. As a result, both genetic polymorphisms modulate DNA adduct levels in lymphocytes by BaP ex vivo. PMID:23325794

Schults, Marten A; Chiu, Roland K; Nagle, Peter W; Wilms, Lonneke C; Kleinjans, Jos C; van Schooten, Frederik J; Godschalk, Roger W



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

PubMed Central

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

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



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

PubMed Central

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 ?g/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. PMID:23134810



Fluoxetin Upregulates Connexin 43 Expression in Astrocyte  

PubMed Central

Introduction Recent studies have shown that astrocytes play major roles in normal and disease condition of the central nervous system including multiple sclerosis (MS). Molecular target therapy studies in MS have revealed that connexin-43 (Cx43) and Aquaporin-4 (AQP4) contents of astrocytes undergo expression alteration. Fluoxetine had some effects in MS patients unrelated to its known antidepressant effects. Some of fluoxetine effects were attributed to its capability of cAMP signaling pathway stimulation. This study aimed to investigate possible acute effects of fluoxetine on Cx43 and AQP4 expression in astrocyte. Methods Astrocytoma cells were treated for 24 hours with fluoxetine (10 and 20 µg/ml) with or without adenyl cyclase (AC) and protein kinase A (PKA) inhibition. Cx43 expression at both mRNA and protein levels and AQP4 expression at mRNA level were evaluated. Results Acquired results showed that fluoxetine with and without AC and PKA inhibition resulted in Cx43 up-regulation both in mRNA and protein levels, whereas AQP4 expression have not changed. Discussion In conclusion, data showed that fluoxetine alone and in the absence of serotonin acutely up-regulated Cx43 expression in astrocytes that can be assumed in molecular target therapy of MS patients. It seems that cAMP involvement in fluoxetine effects need more researches. PMID:25436087

Mostafavi, Hossein; Khaksarian, Mojtaba; Joghataei, Mohammad Taghi; Hassanzadeh, Gholamreza; Soleimani, Masoud; Eftekhari, Sanaz; Soleimani, Mansooreh; Mousavizadeh, Kazem; Hadjighassem, Mahmoud Reza



Catalase Overexpression Reduces Lactic Acid-Induced Oxidative Stress in Saccharomyces cerevisiae?  

PubMed Central

Industrial production of lactic acid with the current pyruvate decarboxylase-negative Saccharomyces cerevisiae strains requires aeration to allow for respiratory generation of ATP to facilitate growth and, even under nongrowing conditions, cellular maintenance. In the current study, we observed an inhibition of aerobic growth in the presence of lactic acid. Unexpectedly, the cyb2? reference strain, used to avoid aerobic consumption of lactic acid, had a specific growth rate of 0.25 h?1 in anaerobic batch cultures containing lactic acid but only 0.16 h?1 in identical aerobic cultures. Measurements of aerobic cultures of S. cerevisiae showed that the addition of lactic acid to the growth medium resulted in elevated levels of reactive oxygen species (ROS). To reduce the accumulation of lactic acid-induced ROS, cytosolic catalase (CTT1) was overexpressed by replacing the native promoter with the strong constitutive TPI1 promoter. Increased activity of catalase was confirmed and later correlated with decreased levels of ROS and increased specific growth rates in the presence of high lactic acid concentrations. The increased fitness of this genetically modified strain demonstrates the successful attenuation of additional stress that is derived from aerobic metabolism and may provide the basis for enhanced (micro)aerobic production of organic acids in S. cerevisiae. PMID:19251894

Abbott, Derek A.; Suir, Erwin; Duong, Giang-Huong; de Hulster, Erik; Pronk, Jack T.; van Maris, Antonius J. A.



Catalase plays a key role in salt stress acclimation induced by hydrogen peroxide pretreatment in maize.  


Pretreatment in plants is recognized as a valuable strategy to stimulate plant defenses, leading to better plant development. This study evaluated the effects of H?O? leaf spraying pretreatment on plant growth and investigated the antioxidative mechanisms involved in the response of maize plants to salt stress. It was found that salinity reduced maize seedling growth when compared to control conditions, and H?O? foliar spraying was effective in minimizing this effect. Analysis of the antioxidative enzymes catalase (EC, guaiacol peroxidase (EC, ascorbate peroxidase (EC and superoxide dismutase (EC revealed that H?O? spraying increased antioxidant enzyme activities. Catalase (CAT) was the most responsive of these enzymes to H?O?, with higher activity early (48 h) in the treatment, while guaiacol peroxidase (GPX) and ascorbate peroxidase (APX) were responsive only at later stages (240 h) of treatment. Increased CAT activity appears linked to gene expression regulation. Lower malondialdehyde levels were detected in plants with higher CAT activity, which may result from the protective function of this enzyme. Overall, we can conclude that pretreatment with H?O? leaf spraying was able to reduce the deleterious effects of salinity on seedling growth and lipid peroxidation. These responses could be attributed to the ability of H?O? to induce antioxidant defenses, especially CAT activity. PMID:22609456

Gondim, Franklin Aragão; Gomes-Filho, Enéas; Costa, José Hélio; Mendes Alencar, Nara Lídia; Prisco, José Tarquinio



Isonicotinic Acid Hydrazide Conversion to Isonicotinyl-NAD by Catalase-peroxidases*  

PubMed Central

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 ? 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

Wiseman, Ben; Carpena, Xavi; Feliz, Miguel; Donald, Lynda J.; Pons, Miquel; Fita, Ignacio; Loewen, Peter C.



Isonicotinic acid hydrazide conversion to Isonicotinyl-NAD by catalase-peroxidases.  


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. PMID:20554537

Wiseman, Ben; Carpena, Xavi; Feliz, Miguel; Donald, Lynda J; Pons, Miquel; Fita, Ignacio; Loewen, Peter C



Catalase-like activity studies of the manganese(II) adsorbed zeolites  

NASA Astrophysics Data System (ADS)

Preparation of manganese(II) adsorbed on zeolite 3A, 4A, 5A. AW-300, ammonium Y zeolite, organophilic, molecular sieve and catalase-like enzyme activity of manganese(II) adsorbed zeolites are reported herein. Firstly zeolites are activated at 873 K for two hours before contact manganese(II) ions. In order to observe amount of adsorption, filtration process applied for the solution. The pure zeolites and manganese(II) adsorbed zeolites were analysed by FT-IR. As a result according to the FT-IR spectra, the incorporation of manganese(II) cation into the zeolite structure causes changes in the spectra. These changes are expected particularly in the pseudolattice bands connected with the presence of alumino and silicooxygen tetrahedral rings in the zeolite structure. Furthermore, the catalytic activities of the Mn(II) adsorbed zeolites for the disproportionation of hydrogen peroxide were investigated in the presence of imidazole. The Mn(II) adsorbed zeolites display efficiency in the disproportion reactions of hydrogen peroxide, producing water and dioxygen in catalase-like activity.

?içek, Ekrem; Dede, Bülent



Characterization of glutathione reductase and catalase in the fronds of two Pteris ferns upon arsenic exposure.  


To better understand the mechanisms of plant tolerance to high concentration of arsenic, we characterized two antioxidant enzymes, glutathione reductase (GR) and catalase (CAT), in the fronds of Pteris vittata, an arsenic-hyperaccumulating fern, and Pteris ensiformis, an arsenic-sensitive fern. The induction, activation and apparent kinetics of GR and CAT in the plants upon arsenic exposure were investigated. Under arsenic exposure (sodium arsenate), CAT activity in P. vittata was increased by 1.5-fold, but GR activity was unchanged. Further, GR was not inhibited or activated by the arsenic in assays. No significant differences in K(m) and V(max) values of GR or CAT were observed between the two ferns. However, CAT activity in P. vittata was activated by 200 microM arsenate up to 300% compared to the control. Similar but much smaller increases were observed for P. ensiformis and purified bovine liver catalase (133% and 120%, respectively). This research reports, for the first time, the activation of CAT by arsenic in P. vittata. The increased CAT activities may allow P. vittata to more efficiently mediate arsenic-induced stress by preparing the fern for the impeding production of reactive oxygen species resulting from arsenate reduction to arsenite in the fronds. PMID:19574057

Kertulis-Tartar, Gina M; Rathinasabapathi, Bala; Ma, Lena Q



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


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 strain KBAB4 as a model, we investigated the impact of the culturing temperature on mild-oxidative-stress-induced (cross-)protection toward multiple stresses, including severe oxidative, heat, and acid stresses. Culturing at a refrigeration temperature (7°C) compared to the optimal growth temperature (30°C) affected both the robustness level of B. weihenstephanensis and the oxidative stress adaptive response. Scavengers of reactive oxygen species have a crucial role in adaptation to oxidative stresses, and this points to a possible predictive role in mild-oxidative-stress-induced robustness. Therefore, the catalase activity was determined upon mild oxidative stress treatment and was demonstrated to be significantly correlated with the robustness level of mild-stress-treated cells toward severe oxidative and heat stresses but not toward severe acid stress for cells grown at both refrigeration and optimal temperatures. The quantified correlations supported the predictive quality of catalase activity as a biomarker and also underlined that the predictive quality is stress specific. Biomarkers that are able to predict stress-induced enhanced robustness can be used to better understand stress adaptation mechanisms and might allow the design of effective combinations of hurdles to control microbial behavior. PMID:23064331

den Besten, Heidy M W; Effraimidou, Styliani; Abee, Tjakko



Upregulation of the thioredoxin-dependent redox system during differentiation of 3T3-L1 cells to adipocytes.  


Hydrogen peroxide acts as a signaling molecule in early adipogenesis. In differentiating adipocytes, elevated hydrogen peroxide generation is balanced through induction of antioxidant enzymes such as catalase and peroxiredoxins. Thioredoxin reductases (TrxR) and glutathione peroxidases (GPx) are selenoenzymes that constitute part of the major thiol-dependent antioxidant systems in cells. Here we show that the protein levels of cytoplasmic/nuclear TrxR1 and mitochondrial TrxR2 increase in the course of adipocyte differentiation of 3T3-L1 cells together with the TrxR2 substrate thioredoxin 2 (Trx2), resulting in elevated TrxR activity in mature adipocytes. Gene and protein expression of the GPx isoenzyme GPx4 was also stimulated during adipogenesis. Chronic exposure of 3T3-L1 cells to the anti-adipogenic factors tumor necrosis factor ? (TNF-?) or rapamycin during differentiation suppressed TrxR1 and Trx2 upregulation, concomitantly with inhibition of adipogenesis and lipogenesis. In contrast, TNF-? or rapamycin did not affect expression of TrxRs and their Trx substrates in mature adipocytes. These results indicate that upregulation of the thioredoxin-dependent redox system is linked to the development of an adipocyte phenotype. PMID:24516001

Rajalin, Ann-Marie; Micoogullari, Mustafa; Sies, Helmut; Steinbrenner, Holger



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


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 Fe L(2,3)-edge X-ray absorption spectra of these proteins in physiological solutions, which reveal clear differences in their electronic structures, in that pi back-donation of the Fe atom occurs in catalase, which confers on it a partial ferryl (Fe(4+)) character, while this is not the case in methaemoglobin. The origin of the Fe(4+) character stems from the proximal tyrosine residue. We also find that both systems are in a high spin state. Temperature effects influence the spectra of catalase only weakly, in agreement with previous studies of its chemical activity. We conclude that the high activity of catalase is not only determined by its distal environment but also by its partial ferryl character. PMID:20428565

Bergmann, Nora; Bonhommeau, Sébastien; Lange, Kathrin M; Greil, Stefanie M; Eisebitt, Stefan; de Groot, Frank; Chergui, Majed; Aziz, Emad F



Uncaria tomentosa extracts protect human erythrocyte catalase against damage induced by 2,4-D-Na and its metabolites.  


The effect of ethanolic and aqueous extracts from leaves and bark of Uncaria tomentosa was studied, with particular attention to catalase activity (CAT - EC. We observed that all tested extracts, at a concentration of 250 ?g/mL were not toxic to erythrocyte catalase because they did not decreased its activity. Additionally, we investigated the protective effect of extracts on changes in CAT activity in the erythrocytes incubated with sodium salt of 2,4-dichlorophenoxyacetic acid (2,4-D-Na) and its metabolites i.e., 2,4-dichlorophenol (2,4-DCP) and catechol. Previous investigations showed that these chemicals decreased activity of erythrocyte catalase (Bukowska et al., 2000; Bukowska and Kowalska, 2004). The erythrocytes were divided into two portions. The first portion was incubated for 1 and 5h at 37°C with 2,4-D-Na, 2,4-DCP and catechol, and second portion was preincubated with extracts for 10 min and then incubated with xenobiotics for 1 and 5h. CAT activity was measured in the first and second portion of the erythrocytes. We found a protective effect of the extracts from U. tomentosa on the activity of catalase incubated with xenobiotics studied. Probably, phenolic compounds contained in U. tomentosa scavenged free radicals, and therefore protected active center (containing -SH groups) of catalase. PMID:22426356

Bukowska, Bo?ena; Bors, Milena; Gulewicz, Krzysztof; Koter-Michalak, Maria



Important Role of Catalase in the Cellular Response of the Budding Yeast Saccharomyces cerevisiae Exposed to Ionizing Radiation.  


Ionizing radiation indirectly causes oxidative stress in cells via reactive oxygen species (ROS), such as hydroxyl radicals (OH(-)) generated by the radiolysis of water. We investigated how the catalase function was affected by ionizing radiation and analyzed the phenotype of mutants with a disrupted catalase gene in Saccharomyces cerevisiae exposed to radiation. The wild-type yeast strain and isogenic mutants with disrupted catalase genes were exposed to various doses of (60)Co gamma-rays. There was no difference between the wild-type strain and the cta1 disruption mutant following exposure to gamma-ray irradiation. In contrast, there was a significant decrease in the ctt1 disruption mutant, suggesting that this strain exhibited decreased survival on gamma-ray exposure compared with other strains. In all three strains, stationary phase cells were more tolerant to the exposure of gamma-rays than exponential phase cells, whereas the catalase activity in the wild-type strain and cta1 disruption mutant was higher in the stationary phase than in the exponential phase. These data suggest a correlation between catalase activity and survival following gamma-ray exposure. However, this correlation was not clear in the ctt1 disruption mutant, suggesting that other factors are involved in the tolerance to ROS induced by irradiation. PMID:25416226

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



Salicylic acid and salicylic acid sensitive and insensitive catalases in different genotypes of chickpea against Fusarium oxysporum f. sp. ciceri.  


Differential expression of catalase isozymes in different genotypes of chickpea resistant genotypes- A1, JG-315, JG-11, WR-315, R1-315, Vijaya, ICCV-15017, GBS-964, GBM-10, and susceptible genotypes- JG-62, MNK, ICCV-08321, ICCV-08311, KW-104, ICCV-08123, ICC-4951, ICC-11322, ICC-08116 for wilt disease caused by Fusarium oxysporum. f. sp. ciceri (Foc) was analyzed. Salicylic acid (SA) and H2O2 concentrations were determined in control as well as in plants infected with F. ciceri and found that the high and low levels of salicylic acid and H2O2 in resistant and susceptible genotypes of chickpea respectively. Catalase isozyme activities were detected in the gel and found that no induction of new catalases was observed in all the resistant genotypes and their some of the native catalase isozymes were inhibited; whereas, induction of multiple catalase isozymes was observed in all the screened susceptible genotypes and their activities were not inhibited upon Foc or SA treatments. The above results support the possible role of these isozymes as a marker to identify which genotype of chickpea is expressing systemic acquired resistance. PMID:24431522

Gayatridevi, S; Jayalakshmi, S K; Mulimani, V H; Sreeramulu, K



Immunohistochemical localization and biochemical changes in catalase and superoxide dismutase during metamorphosis in the olfactory system of frog Microhyla ornata.  


Amphibian metamorphosis is characterized by rapid tissue remodeling and drastic changes in the body structure and function. Like other organs, olfactory system also undergoes a dramatic rearrangement as the animal experiences transition from aquatic to terrestrial habitat. Reactive oxygen species (ROS) are known to play an important role during anuran metamorphosis and role of antioxidant enzymes like catalase and superoxide dismutase (SOD) are believed to play a major role in these processes. Therefore, we hypothesize that antioxidant enzymes in the olfactory system may undergo changes that reflect metamorphic processes. Immunohistochemical study revealed the presence of catalase and SOD in the olfactory receptor neurons and also granular reaction in olfactory epithelium of medial diverticulum during metamorphosis. Catalase and SOD immunoreactivity were seen in the epithelium of lateral diverticulum, vomeronasal organ as metamorphosis proceeds and in the apical lining of olfactory epithelium of adult frog. Biochemical study showed that catalase activity gradually increases in the olfactory system from metamorphic stage 40-46 and adult, while SOD activity decreases from stage 40 to 46 and increases in adult. Thus, the localization and relative levels of catalase and SOD during metamorphosis in the olfactory system suggests that these enzymes may be involved in protection from oxidative damage. PMID:22134050

Gaupale, Tekchand C; Londhe, Jayant; Ghaskadbi, Saroj; Subhedar, N K; Bhargava, Shobha



Superoxide dismutase and catalase in Photobacterium damselae subsp. piscicida and their roles in resistance to reactive oxygen species.  


Photobacterium damselae subsp. piscicida (formerly Pasteurella piscicida) is the causative agent of pasteurellosis or pseudotuberculosis in warm water marine fish. Enzymes which neutralize reactive oxygen species, produced during aerobic metabolism or during respiratory burst in fish macrophages, are important virulence factors in many pathogens. This study characterizes a periplasmic superoxide dismutase (SOD) and a cytoplasmic catalase in P. damselae. Purification and partial amino-terminal sequencing confirmed the SOD to be iron-cofactored, with a high degree of homology to other bacterial FeSODs. The SOD was common to all strains analysed in terms of type, location and activity, whilst the catalase varied in activity between strains. The catalase was constitutively expressed, but the SOD appeared to be repressed under low oxygen conditions. In spite of the presence of a periplasmic SOD, P. damselae was susceptible to killing by exogenous superoxide anion generated in a cell-free system. Addition of exogenous SOD to this system did not abolish the bactericidal effect; however, addition of catalase was protective. These results suggest that lack of periplasmic catalase may be implicated in susceptiblity to killing by reactive oxygen species. PMID:10075430

Barnes, A C; Balebona, M C; Horne, M T; Ellis, A E



Evidence for separate substrate binding sites for hydrogen peroxide and cumene hydroperoxide (CHP) in the oxidation of ethanol by catalase  

SciTech Connect

The oxidation of ethanol by purified bovine liver catalase (Sigma, C-40) can be supported by H/sub 2/O/sub 2/ or by CHP. The time course of the H/sub 2/O/sub 2/ supported reaction (using glucose/glucose oxidase as the H/sub 2/O/sub 2/ source) was linear for at least one hr, whereas the rate of acetaldehyde formation in the CHP (4.2 mM) supported reaction decreased with time. When catalase was exposed o CHP for 5 min before the addition of ethanol, the rate of CHP supported ethanol oxidation was reduced by more than 90% compared to incubations where the addition of ethanol preceded that of CHP. In the CHP inhibited state, the peroxidative activity of catalase was not restored by further addition of CHP or ethanol; however, addition of fresh catalase yielded its expected activity. Significantly, the CHP inhibited enzyme was equally effective as the untreated enzyme in catalyzing (a) the oxidation of ethanol in the presence H/sub 2/O/sub 2/ supported peroxidative activity as well as catalytic activity by CHP inhibited catalase points to separate binding sites for H/sub 2/O/sub 2/ and CHP in this reaction. Alternatively, CHP may bind adjacent to a common peroxide active site, thereby sterically impeding the binding of CHP - but not of H/sub 2/O/sub 2/ - to this active site.

DeMaster, E.G.; Nagasawa,ss H.T.



Ultraviolet Light B-Mediated Inhibition of Skin Catalase Activity Promotes Gr-1+CD11b+ Myeloid Cell Expansion  

PubMed Central

Skin cancer incidence and mortality are higher in men compared to women, but the causes of this sex discrepancy remain largely unknown. Ultraviolet light exposure induces cutaneous inflammation and neutralizes cutaneous antioxidants. Gr-1+CD11b+ myeloid cells are heterogeneous bone marrow-derived cells that promote inflammation-associated carcinogenesis. Reduced activity of catalase, an antioxidant present within skin, has been associated with skin carcinogenesis. We utilized the outbred, immune competent Skh-1 hairless mouse model of ultraviolet light B (UVB)-induced inflammation and non-melanoma skin cancer to further define sex discrepancies in UVB-induced inflammation. Our results demonstrated that male skin had relatively lower baseline catalase activity, which was inhibited following acute UVB exposure in both sexes. Further analysis revealed that skin catalase activity inversely correlated with splenic Gr-1+CD11b+ myeloid cell percentage. Acute UVB exposure induced Gr-1+CD11b+ myeloid cell skin infiltration, which was inhibited to a greater extent in males by topical catalase treatment. In chronic UVB studies, we demonstrated that the percentage of splenic Gr-1+CD11b+ myeloid cells was 55% higher in male tumor-bearing mice compared to their female counterparts. Together, our findings indicate that lower skin catalase activity in male mice may at least in part contribute to increased UVB-induced Gr-1+CD11b+ myeloid cells and subsequent skin carcinogenesis. PMID:22030957

Sullivan, Nicholas J.; Tober, Kathleen L.; Burns, Erin M.; Schick, Jonathan S.; Riggenbach, Judith A.; Mace, Thomas A.; Bill, Matthew A.; Young, Gregory S.; Oberyszyn, Tatiana M.; Lesinski, Gregory B.



Claudins upregulation in human colorectal cancer.  


In colorectal cancer tight junction molecular and morphological alterations are poorly understood. In this study, adenocarcinoma tissues and their paired normal mucosa (n = 12) were analyzed for tight junction alterations molecular. The expression of claudin-1, -3 and -4 was upregulated 5.7-, 1.5- and 2.4-fold, respectively, in colorectal tumor tissues in comparison to the normal ones. Although tight junction remains in the cancerous epithelium, its barrier function was altered. Despite claudins overexpression, paracellular permeability to ruthenium red was increased and a significant disorganization of tight junction strands was observed in freeze fracture replicas. Whereas the functional significance of claudin overexpression in colorectal cancer is unclear, these proteins can become potential markers and targets in colorectal cancer. PMID:16253248

de Oliveira, Silvia Souza; de Oliveira, Ivanir Martins; De Souza, Wanderley; Morgado-Díaz, José Andrés



Expression of the catalase gene katA in starter culture Lactobacillus plantarum TISTR850 tolerates oxidative stress and reduces lipid oxidation in fermented meat product  

Microsoft Academic Search

The catalase gene katA of Lactobacillus sakei SR911 was cloned and expressed in Escherichia coli UM2 and Lactobacillus plantarum TISTR850 under strong lactococcal promoter P59 in E. coli–lactococcus expression vector pIL1020. The L. plantarum TISTR850 is a catalase-deficient strain isolated from local fermented meat product. The recombinant L. plantarum TISTR850 was shown to decompose hydrogen peroxide, and catalase activity approximately

W Noonpakdee; S Sitthimonchai; S Panyim; S Lertsiri



Effects of molecular oxygen on detection of superoxide radical with nitroblue tetrazolium and on activity stains for catalase  

SciTech Connect

The usual method of staining polyacrylamide gel electropherograms for superoxide dismutase activity utilizes a photochemical flux of O/sub 2//sup -/ to reduce nitroblue tetrazolium. Superoxide dismutases intercept O/sub 2//sup -/, preventing formazan production and thus causing achromatic bands. In the presence of H/sub 2/O/sub 2/, catalase also yield achromatic bands during this staining procedure. This is due to local elevation of pO/sub 2/ by the catalytic decomposition of H/sub 2/O/sub 2/. O/sub 2/, in turn, inhibits the reduction of the tetrazolium by O/sub 2//sup -/. This phenomenon provides a new activity stain for catalase. A previously described activity stain for catalase has also been reexamined and significantly improved.

Clare, D.A.; Duong, M.N.; Darr, D.; Archibald, F.; Fridovich, I.



Evaluation of a catalase-based method for estimating the shelf-life of pasteurized whole milk  

E-print Network

of MASTER OF SCIENCE August 1988 Major Subject: Food Science and Technology EVALUATION OF A CATALASE-BASED METHOD FOR ESTIMATING THE SHELF-LIFE OP PASTEURIEED WHOLE MILK A Thesis by SUSAN LEE DILL Approved as to style and content by: Ronald L.... Richter (Chairman of Committee) Carl Van rzant (Mem r) Leon H. Russell, Jr. (Member) Gary C. Smith (Head of Department) August 1988 Evaluation of a Catalase-based Method for Estimating the Shelf-life of Pasteurized Whole Milk (May 1988) Susan...

Dill, Susan Lee



A kinetic method for para -nitrophenol determination based on its inhibitory effect on the catalatic reaction of catalase  

Microsoft Academic Search

The inhibitory effect of para-nitrophenol on the catalytic reaction of catalase was investigated. Michaelis-Menten kinetic parameters were determined from\\u000a Lineweaver-Burk plots obtained in the absence or in the presence of the inhibitor. The inhibitor pattern, revealed by the\\u000a Lineweaver-Burk plots, suggested a fully mixed inhibition mechanism. Spectrophotometric monitoring of the indicator reaction:\\u000a $$H_2 O_2 \\\\xrightarrow{{catalase,para - nitrophenol}}H_2 O + \\\\tfrac{1}{2}O_2

Claudia Mure?anu; Lucian Copolovici; Florina Pogùacean



Spectroscopic investigations on the interaction between carbon nanotubes and catalase on molecular level.  


The interactions between well-dispersed multiwalled carbon nanotubes (MWCNTs) and catalase (CAT) were investigated. The activity of CAT was inhibited with the addition of MWCNTs. After deducting the inner filter effect, the fluorescence spectra revealed that the tryptophan (Trp) residues were exposed and the fluorescence intensities of CAT increased with the increase in the MWCNTs concentration. At the same time, the environment of the Trp residues became more hydrophobic. The results of UV-vis absorption spectroscopy and CD spectra indicated that the secondary structure of CAT had been changed, and the amino acid residues were located in a more hydrophobic environment. Meanwhile, the UV-vis spectra indicated that the conformation of the heme porphyrin rings was changed. The microenvironment of CAT activity sites may be interfered by MWCNTs. This research showed that MWCNTs could not only contribute to the conformational changes of protein but also change the enzyme function. PMID:24616245

Guan, Jin; Dai, Jingping; Zhao, Xingchen; Liu, Chunhua; Gao, Canzhu; Liu, Rutao



Sixty years from discovery to solution: crystal structure of bovine liver catalase form III  

SciTech Connect

The crystallization and structural characterization of bovine liver catalase (BLC) has been intensively studied for decades. Forms I and II of BLC have previously been fully characterized using single-crystal X-ray diffraction. Form III has previously been analyzed by electron microscopy, but owing to the thinness of this crystal form an X-ray crystal structure had not been determined. Here, the crystal structure of form III of BLC is presented in space group P212121, with unit-cell parameters a = 68.7, b = 173.7, c = 186.3 {angstrom}. The asymmetric unit is composed of the biological tetramer, which is packed in a tetrahedron motif with three other BLC tetramers. This higher resolution structure has allowed an assessment of the previously published electron-microscopy studies.

Foroughi, Leila M.; Kang, You-Na; Matzger, Adam J. (Michigan)



Catalase-positive microperoxisomes in rat soleus and extensor digitorum longus muscle fiber types  

NASA Technical Reports Server (NTRS)

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.

Riley, Danny A.; Bain, James L. W.; Ellis, Stanley



Catalase-peroxidase (Mycobacterium tuberculosis KatG) catalysis and isoniazid activation.  


Resonance Raman spectra of native, overexpressed M. tuberculosis catalase-peroxidase (KatG), the enzyme responsible for activation of the antituberculosis antibiotic isoniazid (isonicotinic acid hydrazide), have confirmed that the heme iron in the resting (ferric) enzyme is high-spin five-coordinate. Difference Raman spectra did not reveal a change in coordination number upon binding of isoniazid to KatG. Stopped-flow spectrophotometric studies of the reaction of KatG with stoichiometric equivalents or small excesses of hydrogen peroxide revealed only the optical spectrum of the ferric enzyme with no hypervalent iron intermediates detected. Large excesses of hydrogen peroxide generated oxyferrous KatG, which was unstable and rapidly decayed to the ferric enzyme. Formation of a pseudo-stable intermediate sharing optical characteristics with the porphyrin pi-cation radical-ferryl iron species (Compound I) of horseradish peroxidase was observed upon reaction of KatG with excess 3-chloroperoxybenzoic acid, peroxyacetic acid, or tert-butylhydroperoxide (apparent second-order rate constants of 3.1 x 10(4), 1.2 x 10(4), and 25 M(-1) s(-1), respectively). Identification of the intermediate as KatG Compound I was confirmed using low-temperature electron paramagnetic resonance spectroscopy. Isoniazid, as well as ascorbate and potassium ferrocyanide, reduced KatG Compound I to the ferric enzyme without detectable formation of Compound II in stopped-flow measurements. This result differed from the reaction of horseradish peroxidase Compound I with isoniazid, during which Compound II was stably generated. These results demonstrate important mechanistic differences between a bacterial catalase-peroxidase and the homologous plant peroxidases and yeast cytochrome c peroxidase, in its reactions with peroxides as well as substrates. PMID:10933818

Chouchane, S; Lippai, I; Magliozzo, R S



A gas-phase amplified quartz crystal microbalance immunosensor based on catalase modified immunoparticles.  


A novel signal amplification strategy for quartz crystal microbalance (QCM) based on catalytic gas generation was developed to construct an ultrasensitive immunosensor for the detection of proteins (immunoglobulin G, IgG, used as a model). A catalase modified immunoparticle was prepared to form a sandwich-type immunocomplex with the IgG and anti-IgG antibodies that were immobilized on the QCM sensor. The amount of immunoparticles on the sensor surface was thus controlled by the IgG concentration. Then H2O2 was added and catalyzed by catalase for oxygen generation. The generated oxygen replaced some of the liquid on the sensor surface, leading to the change in the shear modulus of the immunocomplex layer and the apparent viscosity and density of the liquid layer. Due to the ultrasensitive response of QCM to these changes, a significant frequency shift related to the IgG concentration was achieved. Different parameters, including the flow cell structure, operation temperature, immunoparticle concentration, and H2O2 concentration were optimized to achieve steady and efficient frequency shifts. Under the optimal conditions, the proposed gas-phase amplified QCM sensor could achieve up to 72 times improvement of detection sensitivity compared to the label-free sensor as a control, in the concentration range of 0.1-3.0 ?g mL(-1). The detection limit was also reduced from 236 ng mL(-1) to 51.0 ng mL(-1) at the 3Sblank level. PMID:25519742

Liu, Wei; Huang, Renliang; Qi, Wei; Wang, Mengfan; Su, Rongxin; He, Zhimin



Erythropoietin upregulation in pulmonary arterial hypertension  

PubMed Central

Abstract The pathophysiologic alterations of patients with pulmonary arterial hypertension (PAH) are diverse. We aimed to determine novel pathogenic pathways from circulating proteins in patients with PAH. Multianalyte profiling (MAP) was used to measure 90 specifically selected antigens in the plasma of 113 PAH patients and 51 control patients. Erythropoietin (EPO) functional activity was assessed via in vitro pulmonary artery endothelial cell networking and smooth muscle cell proliferation assays. Fifty-eight patients had idiopathic PAH, whereas 55 had other forms of PAH; 5 had heritable PAH, 18 had connective tissue disease (15 with scleroderma and 3 with lupus erythematosis), 13 had portopulmonary hypertension, 6 had PAH associated with drugs or toxins, and 5 had congenital heart disease. The plasma-antigen profile of PAH revealed increased levels of several novel biomarkers, including EPO. Immune quantitative and histochemical studies revealed that EPO not only was significantly elevated in the plasma of PAH patients but also promoted pulmonary artery endothelial cell network formation and smooth muscle cell proliferation. MAP is a hypothesis-generating approach to identifying novel pathophysiologic pathways in PAH. EPO is upregulated in the circulation and lungs of patients with PAH and may affect endothelial and smooth muscle cell proliferation. PMID:25006446



Effect of moderated pressure on the activity and termostability of three microbial enzymes: catalase, ?-galactosidase and alcohol dehydrogenase  

Microsoft Academic Search

The effect of moderate gas pressure on the activity and termostability of three microbial enzymes: catalase from Aspergillus niger, ?-galactosidase from Escherichia coli and alcohol dehydrogenase from Saccharomyces cerevisiae was study. Batch assays were carried out in a hyperbaric bioreactor at increased pressure up to 9 bar using the activity at atmospheric pressure as pattern. Interactions between the effects of

Helena Ribeiro; Manuel Mota; Isabel Belo


Protein and nucleotide contamination of bovine liver catalase used in culture medium explains growth of Trypanosoma cruzi.  


Commercially available bovine liver catalase has been used to supplement chemically defined medium for growth of Trypanosoma cruzi. The protein extract was found to be contaminated with 25 to 30 protein bands as well as DNA and RNA polymers. PMID:2451330

O'Daly, J A; Rodríguez, M B



Effects of molecular oxygen on detection of superoxide radical with nitroblue tetrazolium and on activity stains for catalase  

Microsoft Academic Search

The usual method of staining polyacrylamide gel electropherograms for superoxide dismutase activity utilizes a photochemical flux of Oâ⁻ to reduce nitroblue tetrazolium. Superoxide dismutases intercept Oâ⁻, preventing formazan production and thus causing achromatic bands. In the presence of HâOâ, catalase also yield achromatic bands during this staining procedure. This is due to local elevation of pOâ by the catalytic decomposition

D. A. Clare; M. N. Duong; D. Darr; F. Archibald; I. Fridovich



Original Contribution The induction of human superoxide dismutase and catalase in vivo: A fundamentally new approach to antioxidant therapy  

Microsoft Academic Search

A composition consisting of extracts of five widely studied medicinal plants (Protandim) was administered to healthy human subjects ranging in age from 20 to 78 years. Individual ingredients were selected on the basis of published findings of induction of superoxide dismutase (SOD) and\\/or catalase in rodents in vivo, combined with evidence of decreasing lipid peroxidation. Each ingredient was present at

Sally K. Nelson; Swapan K. Bose; Gary K. Grunwald; Paul Myhill; Joe M. McCord


The induction of human superoxide dismutase and catalase in vivo: a fundamentally new approach to antioxidant therapy.  


A composition consisting of extracts of five widely studied medicinal plants (Protandim) was administered to healthy human subjects ranging in age from 20 to 78 years. Individual ingredients were selected on the basis of published findings of induction of superoxide dismutase (SOD) and/or catalase in rodents in vivo, combined with evidence of decreasing lipid peroxidation. Each ingredient was present at a dosage sufficiently low to avoid any accompanying unwanted pharmacological effects. Blood was analyzed before supplementation and after 30 and 120 days of supplementation (675 mg/day). Erythrocytes were assayed for SOD and catalase, and plasma was assayed for lipid peroxidation products as thiobarbituric acid-reacting substances (TBARS), as well as uric acid, C-reactive protein, and cholesterol (total, LDL, and HDL). Before supplementation, TBARS showed a strong age-dependent increase. After 30 days of supplementation, TBARS declined by an average of 40% (p = 0.0001) and the age-dependent increase was eliminated. By 120 days, erythrocyte SOD increased by 30% (p < 0.01) and catalase by 54% (p < 0.002). We conclude that modest induction of the catalytic antioxidants SOD and catalase may be a much more effective approach than supplementation with antioxidants (such as vitamins C and E) that can, at best, stoichiometrically scavenge a very small fraction of total oxidant production. PMID:16413416

Nelson, Sally K; Bose, Swapan K; Grunwald, Gary K; Myhill, Paul; McCord, Joe M



The induction of human superoxide dismutase and catalase in vivo: A fundamentally new approach to antioxidant therapy  

Microsoft Academic Search

A composition consisting of extracts of five widely studied medicinal plants (Protandim) was administered to healthy human subjects ranging in age from 20 to 78 years. Individual ingredients were selected on the basis of published findings of induction of superoxide dismutase (SOD) and\\/or catalase in rodents in vivo, combined with evidence of decreasing lipid peroxidation. Each ingredient was present at

Sally K. Nelson; Swapan K. Bose; Gary K. Grunwald; Paul Myhill; Joe M. McCord



Characterization of a pathogen-induced potato catalase and its systemic expression upon nematode and bacterial infection.  


We have isolated a cDNA encoding a catalase (Cat2St) by differential screening of a cDNA library constructed from potato roots infected with the cyst nematode Globodera pallida. Expression analysis confirmed the local induction of Cat2St and showed that it was highest at the adult stage of the parasite. It also revealed that Cat2St was induced in uninfected roots, stems, and leaves of infected plants. Localized and systemic induction of Cat2St was also observed upon root-knot nematode (Meloidogyne incognita) and root bacteria (Erwinia carotovora, Corynebacterium sepedonicum) infections. Based on sequence and expression analysis, Cat2St was found to belong to the recently described class II of dicotyledonous catalases, suggesting that these catalase isoforms could also be pathogen induced. Plant-parasitic nematodes are known to induce, in the roots of their hosts, highly metabolic feeding cells that function as nutritional sinks. Whereas the local induction of Cat2St is probably a consequence of an oxidative stress of metabolic nature, the systemic induction of Cat2St shows striking similarities with the induction of systemic acquired resistance (SAR) genes. The possible role of catalase in compatible plant-pathogen interactions is discussed. PMID:7655060

Niebel, A; Heungens, K; Barthels, N; Inzé, D; Van Montagu, M; Gheysen, G



232 1\\'1. POLONOVSKI. -L'AMMONIAQUE catalase n'est pas forte et s'exprime volumtrique ment par 0,5-1,0.  

E-print Network

232 1\\'1. POLONOVSKI. - L'AMMONIAQUE catalase n'est pas forte et s'exprime volumétrique ment par 0,5-1,0. 3. La catalase ne peut pas servir à la définition -de la qualité du levainlactique. BIBLIOGRAPHIE

Boyer, Edmond


Isolation of a novel peroxisomal catalase gene from sugarcane, which is responsive to biotic and abiotic stresses.  


Catalase is an iron porphyrin enzyme, which serves as an efficient scavenger of reactive oxygen species (ROS) to avoid oxidative damage. In sugarcane, the enzymatic activity of catalase in a variety (Yacheng05-179) resistant to the smut pathogen Sporisorium scitamineum was always higher than that of the susceptible variety (Liucheng03-182), suggesting that catalase activity may have a positive correlation with smut resistance in sugarcane. To understand the function of catalase at the molecular level, a cDNA sequence of ScCAT1 (GenBank Accession No. KF664183), was isolated from sugarcane infected by S. scitamineum. ScCAT1 was predicted to encode 492 amino acid residues, and its deduced amino acid sequence shared a high degree of homology with other plant catalases. Enhanced growth of ScCAT1 in recombinant Escherichia coli Rosetta cells under the stresses of CuCl2, CdCl2 and NaCl indicated its high tolerance. Q-PCR results showed that ScCAT1 was expressed at relatively high levels in the bud, whereas expression was moderate in stem epidermis and stem pith. Different kinds of stresses, including S. scitamineum challenge, plant hormones (SA, MeJA and ABA) treatments, oxidative (H2O2) stress, heavy metal (CuCl2) and hyper-osmotic (PEG and NaCl) stresses, triggered a significant induction of ScCAT1. The ScCAT1 protein appeared to localize in plasma membrane and cytoplasm. Furthermore, histochemical assays using DAB and trypan blue staining, as well as conductivity measurement, indicated that ScCAT1 may confer the sugarcane immunity. In conclusion, the positive response of ScCAT1 to biotic and abiotic stresses suggests that ScCAT1 is involved in protection of sugarcane against reactive oxidant-related environmental stimuli. PMID:24392135

Su, Yachun; Guo, Jinlong; Ling, Hui; Chen, Shanshan; Wang, Shanshan; Xu, Liping; Allan, Andrew C; Que, Youxiong



Low erythrocyte catalase enzyme activity is correlated with high serum total homocysteine levels in tunisian patients with acute myocardial infarction  

PubMed Central

Background An imbalance between pro-oxidants and antioxidant systems has been suggested to be implicated in the physiopathology of acute myocardial infarction (AMI). We aimed to evaluate the antioxidant capacity in Tunisian patients and to assess the possible relationship between erythrocyte catalase enzyme activity and hyperhomocysteinaemia. Methods 108 patients with AMI and 81 healthy subjects were enrolled in this study. Catalase erythrocyte enzyme activity was determined spectrophotometrically whereas “total antioxidant status” (TAS) concentration was measured by a commercially available method. Serum total homocysteine (tHcy) level was determined by a fluorescence polarization immunoassay (FPIA). Lipid peroxidation was measured with a fluorimetric method as “thiobarbituric acid reactive substances” (TBARS). Results Compared with healthy subjects, patients with AMI had significantly lower catalase activity (P<0.001), TAS concentrations (P<0.001), and significantly higher serum tHcy (P<0.001) and TBARS levels (P<0.001). Erythrocyte catalase enzyme activity was negatively correlated with serum tHcy and TBARS while serum tHcy and TBARS were in positive correlation. Furthermore, the unbalance between pro-oxidants and antioxidants seems to be more aggravated in patients with Q wave AMI compared to patients with non-Q wave AMI. Conclusion Our results suggest the involvement of hyperhomocysteinaemia in the drop of erythrocyte catalase activity related to myocardial ischemia reperfusion. Hyperhomocysteinaemia may increase the myocardial wall dysfunction under ischemia reperfusion by excessive production of reactive oxygen species which is made evident by increased lipid peroxidation. Virtual slides The virtual slide(s) for this article can be found here: PMID:23631751



Catalase abrogates ?-lapachone-induced PARP1 hyperactivation-directed programmed necrosis in NQO1-positive breast cancers  

PubMed Central

Improving patient outcome by personalized therapy involves a thorough understanding of an agent’s mechanism of action. ?-Lapachone (clinical forms, Arq501/Arq761) has been developed to exploit dramatic cancer-specific elevations in the phase II detoxifying enzyme, NAD(P)H:quinone oxidoreductase (NQO1). NQO1 is dramatically elevated in solid cancers, including primary and metastatic (e.g., triple-negative (ER-, PR-, Her2/Neu-)) breast cancers. To define cellular factors that influence the efficacy of ?-lapachone using knowledge of its mechanism of action, we confirmed that NQO1 was required for lethality and mediated a futile redox cycle where ~120 moles of superoxide were formed per mole of ?-lapachone in 5 min. ?-Lapachone induced reactive oxygen species (ROS), stimulated DNA single strand break-dependent PARP1 hyperactivation, caused dramatic loss of essential nucleotides (NAD+/ATP) and elicited programmed necrosis in breast cancer cells. While PARP1 hyperactivation and NQO1 expression were major determinants of ?-lapachone-induced lethality, alterations in catalase expression, including treatment with exogenous enzyme, caused marked cytoprotection. Thus, catalase is an important resistance factor, and highlights H2O2 as an obligate ROS for cell death from this agent. Exogenous superoxide dismutase (SOD) enhanced catalase-induced cytoprotection. ?-Lapachone-induced cell death included AIF translocation from mitochondria to nuclei, TUNEL+ staining, atypical PARP1 cleavage, and GAPDH S-nitrosylation, which were abrogated by catalase. We predict that the ratio of NQO1:catalase activities in breast cancer versus associated normal tissue are likely to be the major determinants affecting the therapeutic window of ?-lapachone and other NQO1 bioactivatable drugs. PMID:23883585

Bey, Erik A.; Reinicke, Kathryn E.; Srougi, Melissa C.; Varnes, Marie; Anderson, Vernon; Pink, John J.; Li, Long Shan; Patel, Malina; Cao, Lifen; Moore, Zachary; Rommel, Amy; Boatman, Michael; Lewis, Cheryl; Euhus, David M.; Bornmann, William G.; Buchsbaum, Donald J.; Spitz, Douglas R.; Gao, Jinming; Boothman, David A.



Further studies on O sub 2 -resistant photosynthesis and photorespiration in a tobacco mutant with enhanced catalase activity  

SciTech Connect

The increase in net photosynthesis in M{sub 4} progeny of an O{sub 2}-resistant tobacco (Nicotiana tabacum) mutant relative to wild-type plants at 21 and 42% O{sub 2} has been confirmed and further investigated. Self-pollination of an M{sub 3} mutant produced M{sub 4} progeny segregating high catalase phenotypes (average 40% greater than wild type) at a frequency of about 60%. The high catalase phenotype cosegregated precisely with O{sub 2}-resistant photosynthesis. About 25% of the F{sub 1} progeny of reciprocal crosses between the same M{sub 3} mutant and wild type had high catalase activity, whether the mutant was used as the maternal or paternal parent, indicating nuclear inheritance. In high-catalase mutants the activity of NADH-hydroxypyruvate reductase, another peroxisomal enzyme, was the same as wild type. The mutants released 15% less photorespiratory CO{sub 2} as a percent of net photosynthesis in CO{sub 2}-free 21% O{sub 2} and 36% less in CO{sub 2}-free 42% O{sub 2} compared with wild type. The mutant leaf tissue also released less {sup 14}CO{sub 2} per (1-{sup 14}C)glycolate metabolized than wild type in normal air, consistent with less photorespiration in the mutant. The O{sub 2}-resistant photosynthesis appears to be caused by a decrease in photorespiration especially under conditions of high O{sub 2} where the stoichiometry of CO{sub 2} release per glycolate metabolized is expected to be enhanced. The higher catalase activity in the mutant may decrease the nonenzymatic peroxidation of keto-acids such as hydroxypyruvate and glyoxylate by photorespiratory H{sub 2}O{sub 2}.

Zelitch, I. (Connecticut Agricultural Experiment Station, New Haven (USA))



Isolation of a Novel Peroxisomal Catalase Gene from Sugarcane, Which Is Responsive to Biotic and Abiotic Stresses  

PubMed Central

Catalase is an iron porphyrin enzyme, which serves as an efficient scavenger of reactive oxygen species (ROS) to avoid oxidative damage. In sugarcane, the enzymatic activity of catalase in a variety (Yacheng05–179) resistant to the smut pathogen Sporisorium scitamineum was always higher than that of the susceptible variety (Liucheng03–182), suggesting that catalase activity may have a positive correlation with smut resistance in sugarcane. To understand the function of catalase at the molecular level, a cDNA sequence of ScCAT1 (GenBank Accession No. KF664183), was isolated from sugarcane infected by S. scitamineum. ScCAT1 was predicted to encode 492 amino acid residues, and its deduced amino acid sequence shared a high degree of homology with other plant catalases. Enhanced growth of ScCAT1 in recombinant Escherichia coli Rosetta cells under the stresses of CuCl2, CdCl2 and NaCl indicated its high tolerance. Q-PCR results showed that ScCAT1 was expressed at relatively high levels in the bud, whereas expression was moderate in stem epidermis and stem pith. Different kinds of stresses, including S. scitamineum challenge, plant hormones (SA, MeJA and ABA) treatments, oxidative (H2O2) stress, heavy metal (CuCl2) and hyper-osmotic (PEG and NaCl) stresses, triggered a significant induction of ScCAT1. The ScCAT1 protein appeared to localize in plasma membrane and cytoplasm. Furthermore, histochemical assays using DAB and trypan blue staining, as well as conductivity measurement, indicated that ScCAT1 may confer the sugarcane immunity. In conclusion, the positive response of ScCAT1 to biotic and abiotic stresses suggests that ScCAT1 is involved in protection of sugarcane against reactive oxidant-related environmental stimuli. PMID:24392135

Ling, Hui; Chen, Shanshan; Wang, Shanshan; Xu, Liping; Allan, Andrew C.; Que, Youxiong



Flavonoid-induced conversion of catalase to its inactive form--Compound II.  


Flavonoids (FlaOHs), plant polyphenols, are ubiquitous components of human diet and are known as antioxidants. However, their prooxidant activity has also been reported. We have recently found that FlaOHs inhibit catalase, the heme enzyme which catalyzes the decomposition of hydrogen peroxide (H2O2) into water and molecular oxygen. The catalytic cycle proceeds with the formation of the intermediate, Compound I (Cpd I), an oxoferryl porphyrin ?-cation radical, the two-electron oxidation product of a heme group. Under conditions of low H2O2 fluxes and in the presence of an appropriate substrate, Cpd I can undergo one-electron reduction to inactive Compound II (Cpd II), oxoferryl derivative without radical site. Here we show that in vitro, under low fluxes of H2O2, FlaOHs reduce Cpd I to inactive Cpd II. Measurable amounts of Cpd II can be formed even in the presence of reduced nicotinamide adenine dinucleotide phosphate (NADPH) at concentration comparable with the investigated FlaOHs. Possible mechanisms of electron transfer from FlaOH molecule to the heme are discussed. PMID:25111015

Krych, J; Gebicki, J L; Gebicka, L



An immunodominant 90-kilodalton Aspergillus fumigatus antigen is the subunit of a catalase.  

PubMed Central

We have identified, purified, and characterized structurally and functionally a 90-kDa immunodominant antigen associated with the water-soluble fraction of Aspergillus fumigatus. This antigen is recognized by 90.3% of serum samples from patients with aspergilloma and should be considered either by itself or better in combination with other purified antigens as a candidate for developing a standardized immunoassay for the detection of aspergilloma. p90 is a glycoprotein containing at least two two N-linked sugar chains of 2 and 5 kDa, respectively, which are not necessary for its reactivity with aspergilloma serum samples. Using specific anti-p90 rabbit serum, we have demonstrated that under native conditions, p90 exists in oligomeric form and has associated catalase activity. This activity is resistant to extreme temperatures (> 60 degrees C), reducing agents (40 mM dithiothreitol), high concentrations of denaturing agents such as 8 M urea and 8% sodium dodecyl sulfate, and treatments with ethanol-chloroform-water (5:3:10 [vol/vol]) mixtures. PMID:7591135

López-Medrano, R; Ovejero, M C; Calera, J A; Puente, P; Leal, F



Effect of Salts and Organic Solvents on the Activity of Halobacterium cutirubrum Catalase  

PubMed Central

Catalase in extracts of the extreme halophile Halobacterium cutirubrum exhibits up to threefold stimulation by 0.5 to 1.5 m monovalent salts and by 0.1 m divalent salts. Above these concentrations, inhibition of enzyme activity is observed. The inhibitory effect, and to some extent the stimulation, is salt-specific; the effectiveness of a salt in inhibiting enzyme activity depends on both cation and anion. Thus, the order of effectiveness is MgCl2 > LiCl > NaCl > KCl > NH4Cl, and LiCl > LiNO3 > Li2SO4. The magnitude of enzyme inhibition for the salts tested is positively correlated with their molar vapor pressure depression in aqueous solution. Stimulation of enzyme activity was observed when one salt was added at its optimal concentration in the presence of inhibiting concentrations of another salt, indicating that the effect on the enzyme is not due to changing water activity but probably to enzyme-salt interaction. Aqueous solutions of ethylene glycol, glycerol, and dimethyl sulfoxide containing no ions influence enzyme activity in the same manner as do salts. PMID:5784214

Lanyi, Janos K.; Stevenson, Joann



Study on the interaction of catalase with pesticides by flow injection chemiluminescence and molecular docking.  


The interaction mechanisms of catalase (CAT) with pesticides (including organophosphates: disulfoton, isofenphos-methyl, malathion, isocarbophos, dimethoate, dipterex, methamidophos and acephate; carbamates: carbaryl and methomyl; pyrethroids: fenvalerate and deltamethrin) were first investigated by flow injection (FI) chemiluminescence (CL) analysis and molecular docking. By homemade FI-CL model of lg[(I0-I)/I]=lgK+nlg[D], it was found that the binding processes of pesticides to CAT were spontaneous with the apparent binding constants K of 10(3)-10(5) L mol(-1) and the numbers of binding sites about 1.0. The binding abilities of pesticides to CAT followed the order: fenvalerate>deltamethrin>disulfoton>isofenphos-methyl>carbaryl>malathion>isocarbophos>dimethoate>dipterex>acephate>methomyl>methamidophos, which was generally similar to the order of determination sensitivity of pesticides. The thermodynamic parameters revealed that CAT bound with hydrophobic pesticides by hydrophobic interaction force, and with hydrophilic pesticides by hydrogen bond and van der Waals force. The pesticides to CAT molecular docking study showed that pesticides could enter into the cavity locating among the four subdomains of CAT, giving the specific amino acid residues and hydrogen bonds involved in CAT-pesticides interaction. It was also found that the lgK values of pesticides to CAT increased regularly with increasing lgP, Mr, MR and MV, suggesting that the hydrophobicity and steric property of pesticide played essential roles in its binding to CAT. PMID:24875908

Tan, Xijuan; Wang, Zhuming; Chen, Donghua; Luo, Kai; Xiong, Xunyu; Song, Zhenghua



Analysis of Oxidative Stress Status, Catalase and Catechol-O-Methyltransferase Polymorphisms in Egyptian Vitiligo Patients  

PubMed Central

Vitiligo is the most common depigmentation disorder of the skin. Oxidative stress is implicated as one of the probable events involved in vitiligo pathogenesis possibly contributing to melanocyte destruction. Evidence indicates that certain genes including those involved in oxidative stress and melanin synthesis are crucial for development of vitiligo. This study evaluates the oxidative stress status, the role of catalase (CAT) and catechol-O-Methyltransferase (COMT) gene polymorphisms in the etiology of generalized vitiligo in Egyptians. Total antioxidant capacity (TAC) and malondialdehyde (MDA) levels as well as CAT exon 9 T/C and COMT 158 G/A polymorphisms were determined in 89 patients and 90 age and sex-matched controls. Our results showed significantly lower TAC along with higher MDA levels in vitiligo patients compared with controls. Meanwhile, genotype and allele distributions of CAT and COMT polymorphisms in cases were not significantly different from those of controls. Moreover, we found no association between both polymorphisms and vitiligo susceptibility. In conclusion, the enhanced oxidative stress with the lack of association between CAT and COMT polymorphisms and susceptibility to vitiligo in our patients suggest that mutations in other genes related to the oxidative pathway might contribute to the etiology of generalized vitiligo in Egyptian population. PMID:24915010

Mehaney, Dina A.; Darwish, Hebatallah A.; Hegazy, Rehab A.; Nooh, Mohammed M.; Tawdy, Amira M.; Gawdat, Heba I.; El-Sawalhi, Maha M.



Expression analysis and characterization of the mutant of a growth-phase- and starvation-regulated monofunctional catalase gene from Xanthomonas campestris pv. phaseoli.  


Analysis of the Xanthomonas campestris pv. phaseoli (Xp) catalase profile using an activity gel revealed at least two distinct monofunctional catalase isozymes denoted Kat1 and Kat2. Kat1 was expressed throughout growth, whereas Kat2 was expressed only during the stationary phase of growth. The nucleotide sequence of a previously isolated monofunctional catalase gene, Xp katE, was determined. The deduced amino acid sequence of Xp KatE showed a high percentage identity to an atypical group of monofunctional catalases that includes the well-characterized E. coli katE. Expression of Xp katE was growth phase-dependent but was not inducible by oxidants. In addition, growth of Xp in a carbon-starvation medium induced expression of the gene. An Xp katE mutant was constructed, and analysis of its catalase enzyme pattern showed that Xp katE coded for the Kat2 isozyme. Xp katE mutant had resistance levels similar to the parental strain against peroxide and superoxide killing at both exponential and stationary phases of growth. Interestingly, the level of total catalase activity in the mutant was similar to that of the parental strain even in stationary phase. These results suggest the existence of a novel compensatory mechanism for the activity of Xp catalase isozymes. PMID:10675038

Vattanaviboon, P; Mongkolsuk, S



Catalase Influence in the Regulation of Coronary Resistance by Estrogen: Joint Action of Nitric Oxide and Hydrogen Peroxide  

PubMed Central

We tested the influence of estrogen on coronary resistance regulation by modulating nitric oxide (NO) and hydrogen peroxide (H2O2) levels in female rats. For this, estrogen levels were manipulated and the hearts were immediately excised and perfused at a constant flow using a Langendorff's apparatus. Higher estrogen levels were associated with a lower coronary resistance, increased nitric oxide bioavailability, and higher levels of H2O2. When oxide nitric synthase blockade by L-NAME was performed, no significant changes were found in coronary resistance of ovariectomized rats. Additionally, we found an inverse association between NO levels and catalase activity. Taken together, our data suggest that, in the absence of estrogen influence and, therefore, reduced NO bioavailability, coronary resistance regulation seems to be more dependent on the H2O2 that is maintained at low levels by increased catalase activity. PMID:24669281

Schenkel, Paulo C.; Fernandes, Rafael O.; Viegas, Vinícius U.; Campos, Cristina; Fernandes, Tânia R. G.; Araujo, Alex Sander da Rosa; Belló-Klein, Adriane



Cytochrome P450 2E1-dependent oxidant stress and upregulation of anti-oxidant defense in liver cells.  


Induction of cytochrome P450 2E1 (CYP2E1) is a central pathway by which ethanol generates oxidative stress. Cytochrome P450 2E1 metabolizes many other toxicologic compounds. Toxicity of these agents is enhanced by ethanol, due to induction of CYP2E1. Cytochrome P450 2E1 is induced under a variety of physiological and pathophysiological conditions. The laboratory at Mount Sinai School of Medicine established HepG2 cell lines that constitutively express human CYP2E1. Ethanol, polyunsaturated fatty acids and iron were toxic to the HepG2 cells that express CYP2E1 (E47 cells) but not control HepG2 cells. The E47 cells had higher glutathione levels than control HepG2 cells due to activation of the genes encoding the heavy and light subunits of gamma glutamyl cysteine synthetase (GCLC and GCLM). There was also a twofold increase in catalase, cytosolic and microsomal glutathione transferase, and heme oxygenase-1 (HO-1) in the E47 cells due to activation of their respective genes. These activations were prevented by anti-oxidants, suggesting that the upregulation of these anti-oxidant genes may reflect an adaptive mechanism to remove CYP2E1-derived oxidants. Increases in nuclear factor erythroid 2-related factor 2 (Nrf2) protein and mRNA were observed in livers of hepatocytes of chronic alcohol-fed and of pyrazole-treated rats or mice, conditions known to elevate CYP2E1. E47 cells showed increased Nrf2 mRNA and protein expression. Upregulation of GCLC and HO-1 in E47 cells is dependent on Nrf2. These results suggest that Nrf2 is activated and its levels are increased when CYP2E1 is elevated. It is suggested that Nrf2 plays a key role in the adaptive response against increased oxidative stress caused by CYP2E1. PMID:16958665

Cederbaum, Arthur I



recA and catalase in H sub 2 O sub 2 -mediated toxicity in Neisseria gonorrhoeae  

SciTech Connect

Neisseria gonorrhoeae cells defective in the biosynthesis of the recA gene product are no more sensitive to hydrogen peroxide than wild-type cells. Although gonococci possess nearly 100-fold-greater catalase levels than Escherichia coli, they are more susceptible to hydrogen peroxide than this organism. The natural niche of gonococci undoubtedly results in exposure to oxidant stress; however, they do not demonstrate particularly efficient antioxidant defense systems.

Hassett, D.J.; Charniga, L.; Cohen, M.S. (Univ. of North Carolina, Chapel Hill (USA))



Effects of Single-Dose Ultraviolet Radiation on Skin Superoxide Dismutase, Catalase, and Xanthine Oxidase in Hairless Mice  

Microsoft Academic Search

The effects of a single exposure to UVB radiation on skin antioxidant enzymes and superoxide-generating xanthine oxidase were examined in Skh:HR-1 hairless mice. Significant decreases in superoxide dismutase (SOD) and catalase (CAT) were observed by 12 h after UV irradiation and remained depressed for up to 72 h. No induction of xanthine dehydrogenase (XD) or xanthine oxidase (XO) occurred with

Barbara C. Pence; Mark F. Naylor



Response of peroxidase and catalase to acid rain stress during seed germination of rice, wheat, and rape  

Microsoft Academic Search

Seed germination of plants with various acid-resistance display different responses to acid rain. To understand the reason\\u000a why such differences occur, the effects of simulated acid rain (pH 2.5–5.0) on the activities of peroxidase (POD) and catalase\\u000a (CAT) during seed germination of rice (O. sativa), wheat (T. aestivum), and rape (B. chinensis var. oleifera) were investigated. Results indicated that the

Lihong Wang; Xiaohua Huang; Qing Zhou



Selective peracetic acid determination in the presence of hydrogen peroxide using a label free enzymatic method based on catalase  

Microsoft Academic Search

Peracetic acid (PAA) is selectively determined in the presence of hydrogen peroxide (H2O2) by using the self-indicating UV–Vis molecular absorption properties of catalase. The PAA reacts with the protein giving\\u000a an intermediate (Cat-I) which is reduced back by the aminoacid core surrounding the hemegroup. Since the original form of\\u000a the enzyme and the Cat-I have different UV–Vis absorption properties, the

Javier Galbán; Vanesa Sanz; Susana de Marcos



Catalase in fluvial biofilms: a comparison between different extraction methods and example of application in a metal-polluted river  

Microsoft Academic Search

Antioxidant enzymes are involved in important processes of cell detoxification during oxidative stress and have, therefore,\\u000a been used as biomarkers in algae. Nevertheless, their limited use in fluvial biofilms may be due to the complexity of such\\u000a communities. Here, a comparison between different extraction methods was performed to obtain a reliable method for catalase\\u000a extraction from fluvial biofilms. Homogenization followed

Chloé Bonnineau; Berta Bonet; Natàlia Corcoll; Helena Guasch



Glucose oxidase and catalase adsorption onto Cibacron Blue F3GA-attached microporous polyamide hollow-fibres  

Microsoft Academic Search

The aim of this study was to explore in detail the performance of polyamide hollow fibers to which Cibacron Blue F3GA was attached for adsorption of proteins. Model proteins were glucose oxidase, as a flavo-enzyme and contains two tightly bound flavine adenine dinucleotide cofactor, and catalase as a heme-containing metallo-enzyme. The hollow fiber structure was characterized by scanning electron microscopy.

Sinan Akgöl; Handan Yavuz; Serap ?enel; Adil Denizli



[Heterologous extracellular expression and initial characterization of the peroxisomal catalase from the methylotrophic yeast Hansenula polymorpha in Pichia pastoris].  


Catalase is well known to eliminate H2O2 in cells and reduces the toxicity of peroxide compounds. A catalase gene HpCat1 of methylotrophic yeast Hansenula polymorpha without the part coding the native signal peptide was cloned into expression vector pYM3165 and then integrated into genome of Pichia pastoris GS115 by electroporation. The result of the enzyme activity assay and SDS-PAGE demonstrated that the recombinant protein (HpCAT1) of H. polymorpha was extracellularly expressed in P. pastoris. The expressed catalase was recovered from the culture supernatant of P. pastoris GS 115 and purified by (NH4) 2SO4 fractionation and Ni-NTA affinity chromatography. The main biochemical properties of the recombinant protein HpCAT1, such as thermodependence and thermostability, pH optimum and pH stability, as well as the effect of metal ions and chemicals, were characterized. With H2O2 as the substrate, HpCAT1 displayed pH and tem- perature optima of approximately 2.6 and 45°C,respectively. The recombinant HpCAT1 activity was inhibited by 1 mM Hg2+ and Cu2+, but was highly enhanced by 1.0 mM Fe2+. PMID:25474874

Tian, Y -S; Xu, H; Peng, R -H; Yao, Q -H



[Heterologous extracellular expression and initial characterization of the peroxisomal catalase from the methylotrophic yeast Hansenula polymorpha in Pichia pastoris].  


Catalase is well known to eliminate H2O2 in cells and reduces the toxicity of peroxide compounds. A catalase gene HpCat1 of methylotrophic yeast Hansenula polymorpha without the part coding the native signal peptide was cloned into expression vector pYM3165 and then integrated into genome of Pichia pastoris GS115 by electroporation. The result of the enzyme activity assay and SDS-PAGE demonstrated that the recombinant protein (HpCAT1) of H. polymorpha was extracellularly expressed in P. pastoris. The expressed catalase was recovered from the culture supernatant of P. pastoris GS 115 and purified by (NH4) 2SO4 fractionation and Ni-NTA affinity chromatography. The main biochemical properties of the recombinant protein HpCAT1, such as thermodependence and thermostability, pH optimum and pH stability, as well as the effect of metal ions and chemicals, were characterized. With H2O2 as the substrate, HpCAT1 displayed pH and tem- perature optima of approximately 2.6 and 45°C,respectively. The recombinant HpCAT1 activity was inhibited by 1 mM Hg2+ and Cu2+, but was highly enhanced by 1.0 mM Fe2+. PMID:25508653



Cloning and characterization of the katA gene of Rhizobium meliloti encoding a hydrogen peroxide-inducible catalase.  

PubMed Central

To investigate the involvement of bacterial catalases of the symbiotic gram-negative bacterium Rhizobium meliloti in the development of Medicago-Rhizobium functional nodules, we cloned a putative kat gene by screening a cosmid library with a catalase-specific DNA probe amplified by PCR from the R. meliloti genome. Nucleotide sequence analysis of a 1.8-kb DNA fragment revealed an open reading frame, called katA, encoding a peptide of 562 amino acid residues with a calculated molecular mass of 62.9 kDa. The predicted amino acid sequence showed a high homology with the primary structure of monofunctional catalases from eucaryotes and procaryotes. The katA gene was localized on the chromosome, and the katA gene product was essentially found in the periplasmic space. A katA::Tn5 mutant was obtained and showed a drastic sensitivity to hydrogen peroxide, indicating an essential protective role of KatA. However, neither Nod nor Fix phenotypes were impaired in the mutant, suggesting that KatA is not essential for nodulation and establishment of nitrogen fixation. Exposure to a sublethal concentration of H2O2 enhanced KatA activity (100-fold) and also increased survival to subsequent H2O2 exposure at higher concentrations. No protection is observed in katA::Tn5, indicating that KatA is the major component of an adaptive response. PMID:8955300

Hérouart, D; Sigaud, S; Moreau, S; Frendo, P; Touati, D; Puppo, A



Manganese L-edge X-ray absorption spectroscopy of manganese catalase from Lactobacillus plantarum and mixed valence manganese complexes  

SciTech Connect

The first Mn L-edge absorption spectra of a Mn metalloprotein are presented in this paper. Both reduced and superoxidized Mn catalase have been examined by fluorescence-detected soft X-ray absorption spectroscopy, and their Mn L-edge spectra are dramatically different. The spectrum of reduced Mn(II)Mn(II) catalase has been interpreted by ligand field atomic multiplet calculations and by comparison to model compound spectra. The analysis finds a 10 Dq value of nearly 1.1 eV, consistent with coordination by predominately nitrogen and oxygen donor ligands. For interpretation of mixed valence Mn spectra, an empirical simulation procedure based on the addition of homovalent model compound spectra has been developed and was tested on a variety of Mn complexes and superoxidized Mn catalase. This routine was also used to determine the oxidation state composition of the Mn in [Ba{sub 8}Na{sub 2}ClMn{sub 16}(OH){sub 8}(CO{sub 3}){sub 4}L{sub 8}] .53 H{sub 2}O (L=1,3-diamino-2-hydroxypropane-N,N,N`N`-tetraacetic acid). 27 refs., 6 figs.

Grush, M.M.; Chen, J.; George, S.J. [Univ. of California, Davis, CA (United States)] [and others] [Univ. of California, Davis, CA (United States); and others



Effect of heavy metal salts on the activity of rat liver and kidney catalase and lysosomal hydrolases.  


The effects of Cu, Fe, Pb and Zn as well as of a Pb + Zn combination on the total, available and nonsedimentable (NS) activities of lysosomal and peroxisomal enzymes were examined. An activating influence on the total activities of liver acid phosphatase (AP) and cathepsin D was shown for Cu. In the kidney the heavy metals induced changes in the total activity only of catalase. The effect of Cu was inhibiting, while that of Pb and of the Pb + Zn combination was activating. Copper produced an increase of NS protease and AP activities in liver homogenates accompanied by a rapid release of latent AP from liver large-granule fractions. According to these data and to generally accepted criteria for assessment of the integrity of lysosomes, Cu can be regarded as a powerful labilizer of lysosomal membranes. This heavy metal induced such an effect on liver peroxisomes as well, a statement which is based on the enhancement of NS catalase activity. In the kidney, Pb and the Pb + Zn combination were shown to produce a significant lowering of NS catalase activity, indicating a stabilization of peroxisomes. PMID:9793465

Popova, M P; Popov, C S



67 effects of antioxidants lactoferrin and catalase on stallion frozen semen.  


During cryopreservation, the sperm were submitted to an increased generation of reactive oxygen species. Furthermore, because of the large portion of seminal plasma removal, there is a decrease of sperm antioxidant protection. Addition of antioxidants proteins found in seminal plasma, such as lactoferrin (Lf) and catalase (Cat), to the freezing semen extenders could protect the sperm during cryopreservation. Lactoferrin is a transferrin, which prevents the hydroxyl radicals generation, and Cat plays an antioxidant role. The aim of this study was to determine the effects of Lf and Cat supplementation to the INRA 82 freezing extender (Battelier et al. 1997) on sperm motility parameters and membrane functionality of stallion frozen semen. Semen from 6 stallions was collected with an artificial vagina, diluted with Kenney extender (1:1), and centrifuged (500×g, 10min). The supernatant was discarded, and sperm number per milliliter was calculated. Semen was resuspended with 3 extenders to 100×10(6)spermmL(-1). The treatments were distributed in (F1) control, INRA 82 freezing extender (Battelier et al. 1997), (F2) F1+ 500?gmL(-1) lactoferrin, and F3) F1+200IUmL(-1) catalase. Semen samples were packaged in 0.5-mL straws and cooled to 5°C (0.27°Cmin(-1)). For semen freezing, the straws were laid over the LN vapor for 20min and plunged into the LN. The straws were thawed at 37°C for 30s. Motility parameters of frozen semen were determined using a computer sperm cell analysis, and sperm membrane functionality was assessed by the hyposmotic swelling test (Lagares et al. 1998). The data were analysed using Friedman test using stallion as a block. A probability of P<0.05 was considered significant. There was no significant difference between the percentage of total sperm motility (median, minimum-maximum value; F1: 29.9, 11.0-82.7; F2: 49.8, 7.7-55.2; F3: 39.8, 5.7-92) and progressive sperm motility (F1: 7.1, 3.2-23.3; F2: 13.4, 2.6-22.4; F3: 15.6, 1.1-29.6), and functional sperm membrane (F1: 26.7, 14.7-56.2; F2: 50.5, 15.7-61.7; F3: 46.6, 13.8-50.9) with regard to the treatment. However, the velocity parameters: velocity average path (F1: 29.3, 22.1-33.80; F2: 34.6, 24.8-44; F3: 35.7, 18.2-42.6), velocity curvilinear (F1: 36.9, 30.5-45.1; F2: 42.5, 34.7-51; F3: 44.6, 25.5-50.9), and velocity straight line (F1: 23.4, 17-3.60; F2: 28.9, 18.8-38.2; F3: 26.6, 13.6-37.2) in the treatment with Lf (F2) were higher compared with the control (F1; P<0.05). These results corroborate with studies reporting the lack of positive effect on equine sperm motility when antioxidants were added to skim milk-based extenders. Although the addition of Lf or Cat to skim milk-based extenders did not improve the motility sperm characteristics and sperm membrane functionality, more studies about the positive effect of Lf on the velocity parameters are necessary. Lactoferrin could then play an important role on the oxidative metabolism, which provides energy to the sperm movement. PMID:25472116

Martins, H S; Brito, M F; Sampaio, I B M; Stahlberg, R; Souza, M R; Penna, C F A M; Lagares, M A



Biodegradable microspheres as carriers for native superoxide dismutase and catalase delivery.  


The purpose of this research was to encapsulate superoxide dismutase (SOD) and catalase (CAT) in biodegradable microspheres (MS) to obtain suitable sustained protein delivery. A modified water/oil/water double emulsion method was used for poly(D,L-lactide-co-glycolide) (PLGA) and poly(D,L-lactide) PLA MS preparation co-encapsulating mannitol, trehalose, and PEG400 for protein stabilization. Size, morphology, porosity, mass loss, mass balance, in vitro release and in vitro activity were assessed by using BCA protein assay, scanning electron microscopy, BET surface area, and particle-sizing techniques. In vitro activity retention within MS was evaluated by nicotinammide adenine dinucleotide oxidation and H2O2 consumption assays. SOD encapsulation efficiency resulted in 30% to 34% for PLA MS and up to 51% for PLGA MS, whereas CAT encapsulation was 34% and 45% for PLGA and PLA MS, respectively. All MS were spherical with a smooth surface and low porosity. Particle mean diameters ranged from 10 to 17 mum. CAT release was prolonged, but the results were incomplete for both PLA and PLGA MS, whereas SOD was completely released from PLGA MS in a sustained manner after 2 months. CAT results were less stable and showed a stronger interaction than SOD with the polymers. Mass loss and mass balance correlated well with the release profiles. SOD and CAT in vitro activity was preserved in all the preparations, and SOD was better stabilized in PLGA MS. PLGA MS can be useful for SOD delivery in its native form and is promising as a new depot system. PMID:15760048

Giovagnoli, Stefano; Blasi, Paolo; Ricci, Maurizio; Rossi, Carlo



Characterization of the binding of isoniazid and analogues to Mycobacterium tuberculosis catalase-peroxidase.  


The first-line antituberculosis drug isonicotinic hydrazide (INH) is a prodrug whose bactericidal function requires activation by Mycobacterium tuberculosis catalase-peroxidase (KatG) to produce an acyl-NAD adduct. Peroxidation of INH is considered a required catalytic process for drug action. The binding of INH and a series of hydrazide analogues to resting KatG was examined using optical and calorimetric techniques to provide thermodynamic parameters, binding stoichiometries, and kinetic constants (on and off rates). This work revealed high-affinity binding of these substrates to a small fraction of ferric enzyme in a six-coordinate heme iron form, a species most likely containing a weakly bound water molecule, which accumulates during storage of the enzyme. The binding of hydrazides is associated with a large enthalpy loss (>100 kcal/mol); dissociation constants are in the range of 0.05-1.6 microM, and optical stopped-flow measurements demonstrated kon values in the range of 0.5-27 x 10(3) M-1 s-1 with very small koff rates. Binding parameters did not depend on pH in the range 5-8. High-affinity binding of INH is disrupted in two mutant enzymes bearing replacements of key distal side residues, KatG[W107F] and KatG[Y229F]. The rates of reduction of KatG Compound I by hydrazides parallel the on rates for association with the resting enzyme. In a KatG-mediated biomimetic activation assay, only isoniazid generated in good yield the acyl-NAD adduct which is considered a key molecule in INH action, providing a better understanding of the action mechanism of INH. PMID:17309235

Zhao, Xiangbo; Yu, Shengwei; Magliozzo, Richard S



Mycobacterial FurA is a negative regulator of catalase-peroxidase gene katG.  


In several bacteria, the catalase-peroxidase gene katG is under positive control by oxyR, a transcriptional regulator of the peroxide stress response. The Mycobacterium tuberculosis genome also contains sequences corresponding to oxyR, but this gene has been inactivated in the tubercle bacillus because of the presence of multiple mutations and deletions. Thus, M. tuberculosis katG and possibly other parts of the oxidative stress response in this organism are either not regulated or are controlled by a factor different from OxyR. The mycobacterial FurA is a homologue of the ferric uptake regulator Fur and is encoded by a gene located immediately upstream of katG. Here, we examine the possibility that FurA regulates katG expression. Inactivation of furA on the Mycobacterium smegmatis chromosome, a mycobacterial species that also lacks an oxyR homologue, resulted in derepression of katG, concomitant with increased resistance of the furA mutant to H2O2. In addition, M. smegmatis furA::Km(r) was more sensitive to the front-line antituberculosis agent isonicotinic acid hydrazide (INH) compared with the parental furA+ strain. The phenotypic manifestations were specific, as the mutant strain did not show altered sensitivity to organic peroxides, and both H2O2 and INH susceptibility profiles were complemented by the wild-type furA+ gene. We conclude that FurA is a second regulator of oxidative stress response in mycobacteria and that it negatively controls katG. In species lacking a functional oxyR, such as M. tuberculosis and M. smegmatis, FurA appears to be a dominant regulator affecting mycobacterial physiology and intracellular survival. PMID:11251835

Zahrt, T C; Song, J; Siple, J; Deretic, V



Evidence for radical formation at Tyr-353 in Mycobacterium tuberculosis catalase-peroxidase (KatG).  


Mycobacterium tuberculosis KatG is a heme-containing catalase-peroxidase responsible for activation, through its peroxidase cycle, of the front line antituberculosis antibiotic isoniazid (isonicotinic acid hydrazide). Formation of Compound I (oxyferryl heme-porphyrin pi-cation radical), the classical peroxidase intermediate generated when the resting enzyme turns over with alkyl peroxides, is rapidly followed by production of a protein-centered tyrosyl radical in this enzyme. In our efforts to identify the residue at which this radical is formed, nitric oxide was used as a radical scavenging reagent. Quenching of the tyrosyl radical generated in the presence of NO was shown using electron paramagnetic resonance spectroscopy, and formation of nitrotyrosine was confirmed by proteolytic digestion followed by high performance liquid chromatography analysis of the NO-treated enzyme. These results are consistent with formation of nitrosyltyrosine by addition of NO to tyrosyl radical and oxidation of this intermediate to nitrotyrosine. Two predominant nitrotyrosine-containing peptides were identified that were purified and sequenced by Edman degradation. Both peptides were derived from the same M. tuberculosis KatG sequence spanning residues 346-356 with the amino acid sequence SPAGAWQYTAK, and both peptides contained nitrotyrosine at residue 353. Some modification of Trp-351 most probably into nitrosotryptophan was also found in one of the two peptides. Control experiments using denatured KatG or carried out in the absence of peroxide did not produce nitrotyrosine. In the mutant enzyme KatG(Y353F), which was constructed using site-directed mutagenesis, a tyrosyl radical was also formed upon turnover with peroxide but in poor yield compared with wild-type KatG. Residue Tyr-353 is unique to M. tuberculosis KatG and may play a special role in the function of this enzyme. PMID:14665627

Zhao, Xiangbo; Girotto, Stefania; Yu, Shengwei; Magliozzo, Richard S



Streptococcus didelphis sp. nov., a streptococcus with marked catalase activity isolated from opossums (Didelphis virginiana) with suppurative dermatitis and liver fibrosis  

Microsoft Academic Search

b-Haemolytic, catalase-positive, Gram-positive cocci that formed chains in broth media but did not react with Lancefield group antisera were isolated from skin lesions, spleen, liver and lungs of nine opossums, including eight from a research colony and one from a wildlife rehabilitation organization. The isolates had vigorous catalase activity that was retained on initial passage on non-blood-containing media, but this

Fred R. Rurangirwa; Charlene A. Teitzel; Jing Cui; Dorothy M. French; Patrick L. McDonough; Thomas Besser


Prognostic significance of catalase expression and its regulatory effects on hepatitis B virus X protein (HBx) in HBV-related advanced hepatocellular carcinomas  

PubMed Central

Hepatitis B virus X protein (HBx) plays a role in liver cancer development. We previously showed that ROS increased HBx levels and here, we investigated the role of antioxidants in the regulation of HBx expression and their clinical relevance. We found that overexpression of catalase induced a significant loss in HBx levels. The cysteine null mutant of HBx (Cys?) showed a dramatic reduction in its protein stability. In clonogenic proliferation assays, Huh7-X cells produced a significant number of colonies whereas Huh7-Cys? cells failed to generate them. The Cys at position 69 of HBx was crucial to maintain its protein stability and transactivation function in response to ROS. Among 50 HBV-related hepatocellular carcinoma (HCC) specimens, 72% of HCCs showed lower catalase levels than those of surrounding non-tumor tissues. In advanced stage IV, catalase levels in non-tumor tissues were increased whereas those in tumors were further reduced. Accordingly, patients with a high T/N ratio for catalase showed significantly longer survival than those with a low T/N ratio. Together, catalase expression in HCC patients can be clinically useful for prediction of patient survival, and restoration of catalase expression in HCCs could be an important strategy for intervention in HBV-induced liver diseases. PMID:25361011

Cho, Mi-Young; Cheong, Jae Youn; Lim, Wonchung; Jo, Sujin; Lee, Youngsoo; Wang, Hee-Jung; Han, Kyou-Hoon; Cho, Hyeseong



Modification of catalase and MAPK in Vicia faba cultivated in soil with high natural radioactivity and treated with a static magnetic field.  


The effects of a static magnetic field (SMF) and high natural radioactivity (HR) on catalase and MAPK genes in Vicia faba were investigated. Soil samples with high natural radioactivity were collected from Ramsar in north Iran where the annual radiation absorbed dose from background radiation is higher than 20mSv/year. The specific activity of the radionuclides of (232)Th, (236)Ra, and (40)K was measured using gamma spectrometry. The seeds were planted either in the soil with high natural radioactivity or in the control soils and were then exposed to a SMF of 30mT for 8 days; 8h/day. Levels of expression of catalase and MAPK genes, catalase activity and H2O2 content were evaluated. The results demonstrated significant differences in the expression of catalase and MAPK genes in SMF- and HR-treated plants compared to the controls. An increase in catalase activity was accompanied by increased expression of its gene and accumulation of H2O2. Relative expression of the MAPK gene in treated plants, however, was lower than those of the controls. The results suggest that the response of V. faba plants to SMF and HR may be mediated by modification of catalase and MAPK. PMID:24484963

Haghighat, Nazanin; Abdolmaleki, Parviz; Ghanati, Faezeh; Behmanesh, Mehrdad; Payez, Atefeh



Novel immobilized liposomal glucose oxidase system using the channel protein OmpF and catalase.  


The reactivity of immobilized glucose oxidase-containing liposomes (IGOL) prepared in our previous work (Wang et al. [2003] Biotechnol Bioeng 83:444-453) was considerably improved here by incorporating the channel protein OmpF from Escherichia coli into the liposome membrane as well as by entrapping inside the liposome's aqueous interior not only glucose oxidase (GO), but also catalase (CA), both from Aspergillus niger. CA was used for decomposing the hydrogen peroxide produced in the glucose oxidation reaction inside the liposomes. The presence of OmpF enhanced the transport of glucose molecules from the exterior of the liposomes to the interior. In a first step of the work, liposomes containing GO and CA (GOCAL) were prepared and characterized. A remarkable protection effect of the liposome membrane on CA inside the liposomes at 40 degrees C was found; the remaining CA activity at 72 h incubation was more than 60% for GOCAL, while less than 20% for free CA. In a second step, OmpF was incorporated into GOCAL membranes, leading to the formation of OmpF-embedded GOCAL (abbreviated GOCAL-OmpF). The activity of GO inside GOCAL-OmpF increased up to 17 times in comparison with that inside GOCAL due to an increased glucose permeation across the liposome bilayer, without any leakage of GO or CA from the liposomes. The optimal system was estimated to contain on average five OmpF molecules per liposome. Finally, GOCAL-OmpF were covalently immobilized into chitosan gel beads. The performance of this novel biocatalyst (IGOCAL-OmpF) was examined by following the change in glucose conversion, as well as by following the remaining GO activity in successive 15-h air oxidations for repeated use at 40 degrees C in an airlift bioreactor. IGOCAL-OmpF showed higher reactivity and reusability than IGOL, as well as IGOL containing OmpF (IGOL-OmpF). The IGOCAL-OmpF gave about 80% of glucose conversion even when the catalyst was used repeatedly four times, while the corresponding conversions were about 60% and 20% for the IGOL and IGOL-OmpF, respectively. Due to the absence of CA, IGOL-OmpF was less stable and resulted in drastically inhibited GO. PMID:15723324

Yoshimoto, Makoto; Wang, Shaoqing; Fukunaga, Kimitoshi; Fournier, Didier; Walde, Peter; Kuboi, Ryoichi; Nakao, Katsumi



[Effects of catalase gene (RS769217) polymorphism on energy homeostasis and bone status are gender specific].  


The pathogenic role of oxidative stress has already been proven both in energy homeostasis and bone metabolism. The effects of +22348C>T (RS769217) polymorphism of catalase (EC, hydrogenperoxid-hydrogenperoxid oxidoreduktase) gene were investigated on glucose disposal and bone mineral density in groups of healthy (n = 24) and glucose intolerant (n = 27) females and healthy (n = 64) and glucose intolerant (n = 26) males. Glucose intolerant groups included IFG, IGT and non-treated type 2 diabetic patients. There were no differences in allele frequencies between the genders and groups in this transdanubian Hungarian population. The effects of CAT gene polymorphisms on glucose metabolism and bone status were gender specific. Females with mutant CAT (CT+TT) gene had better HOMA-IR (CC: 2.95+/-1.8 versus CT+TT: 2.06+/-0.9, p<0.05), but bone density did not differ between the CC and CT+TT haplotypes. The homozygote TT females had significantly better whole body glucose disposal. (M-1 mg/kg/min: CC: 9,43+/-4,4 versus TT: 13,23+/-1,6mg/kg body weight/min, p<0.05). The appearance of T allel among males caused lower femur density (CC: 1,11+/-0,17 versus CT+TT: 1,03+/-0,16, p<0.05 g/cm 2 ) and better HOMA-IR (CC: 2.42+/-2.3 versus CT+TT: 1.50+/-0.2, p<0.05), with no change in whole body glucose disposal. Osteocalcin - which has been proven to be the connection between energy homeostasis and bone metabolism - had identical serum levels in both haplotypes, but the significant correlation between muscle tissue glucose utilization and osteocalcin levels (r = +0.4424, p<0.05, n = 23) disappeared in the presence of T allele. Multiple correlation showed significant connection between leptin/adiponectin and femur BMD in CC female group, and between leptin/adiponectin and lumbar BMD in CC male group. The correlations disappeared with the appearance of T allele. Our results differ from the data obtained in Korean postmenopausal women and stress the need of population/ethnic specific replication of genetic data. PMID:20494887

Vitai, Márta; Kocsordi, Krisztina; Buday, Barbara; Literáti Nagy, Botond; Kulcsár, Eniko; Bezzegh, Katalin; Péterfai, Eva; Koltay, László; Korányi, László



Intrapulmonary lipopolysaccharide exposure upregulates cytokine expression in the neonatal brainstem  

PubMed Central

Perinatal inflammation and neonatal sepsis trigger lung and brain injury. We hypothesized that endotoxin exposure in the immature lung upregulates proinflammatory cytokine expression in the brainstem and impairs respiratory control. Lipopolysaccharide (LPS) or saline was administered intratracheally to vagal intact or denervated rat pups. LPS increased brainstem IL-1? and vagotomy blunted this response. There was an attenuated ventilatory response to hypoxia and increased brainstem IL-1? expression after LPS. Conclusion Intratracheal endotoxin exposure in rat pups is associated with upregulation of IL-1? in the brainstem that is vagally mediated and associated with an impaired hypoxic ventilatory response. PMID:22176020

Balan, Kannan V; Kc, Prabha; Mayer, Catherine A; Wilson, Christopher G; Belkadi, Abdelmadjid; Martin, Richard J



Cytochrome P450-type Hydroxylation and Epoxidation in a Tyrosine-liganded Hemoprotein, Catalase-related Allene Oxide Synthase*  

PubMed Central

The ability of hemoproteins to catalyze epoxidation or hydroxylation reactions is usually associated with a cysteine as the proximal ligand to the heme, as in cytochrome P450 or nitric oxide synthase. Catalase-related allene oxide synthase (cAOS) from the coral Plexaura homomalla, like catalase itself, has tyrosine as the proximal heme ligand. Its natural reaction is to convert 8R-hydroperoxy-eicosatetraenoic acid (8R-HPETE) to an allene epoxide, a reaction activated by the ferric heme, forming product via the FeIV–OH intermediate, Compound II. Here we oxidized cAOS to Compound I (FeV=O) using the oxygen donor iodosylbenzene and investigated the catalytic competence of the enzyme. 8R-hydroxyeicosatetraenoic acid (8R-HETE), the hydroxy analog of the natural substrate, normally unreactive with cAOS, was thereby epoxidized stereospecifically on the 9,10 double bond to form 8R-hydroxy-9R,10R-trans-epoxy-eicosa-5Z,11Z,14Z-trienoic acid as the predominant product; the turnover was 1/s using 100 ?m iodosylbenzene. The enantiomer, 8S-HETE, was epoxidized stereospecifically, although with less regiospecificity, and was hydroxylated on the 13- and 16-carbons. Arachidonic acid was converted to two major products, 8R-HETE and 8R,9S-eicosatrienoic acid (8R,9S-EET), plus other chiral monoepoxides and bis-allylic 10S-HETE. Linoleic acid was epoxidized, whereas stearic acid was not metabolized. We conclude that when cAOS is charged with an oxygen donor, it can act as a stereospecific monooxygenase. Our results indicate that in the tyrosine-liganded cAOS, a catalase-related hemoprotein in which a polyunsaturated fatty acid can enter the active site, the enzyme has the potential to mimic the activities of typical P450 epoxygenases and some capabilities of P450 hydroxylases. PMID:22628547

Boeglin, William E.; Brash, Alan R.



Estimation of volume densities of hepatocytic peroxisomes in a model fish: Catalase conventional immunofluorescence versus cytochemistry for electron microscopy.  


Accurately accessing changes in the intracellular volumes (or numbers) of peroxisomes within a cell can be a lengthy task, because unbiased estimations can be made only by studies conducted under transmission electron microscopy. Yet, such information is often required, namely for correlations with functional data. The optimization and applicability of a fast and new technical proceeding based on catalase immunofluorescence was implemented herein by using primary hepatocytes from brown trout (Salmo trutta f. fario), exposed during 96 h to two distinct treatments (0.1% ethanol and 50 µM of 17?-ethynylestradiol). The time and cost efficiency, together with the results obtained by stereological analyses, specifically directed to the volume densities of peroxisomes, and additionally of the nucleus in relation to the hepatocyte, were compared with the well-established 3,3'-diaminobenzidine cytochemistry for electron microscopy. With the immuno technique it was possible to correctly distinguish punctate peroxisomal profiles, allowing the selection of the marked organelles for quantification. By both methodologies, a significant reduction in the volume density of the peroxisome within the hepatocyte was obtained after an estrogenic input. The most interesting point here was that the volume density ratios were quite correlated between both techniques. Overall, the immunofluorescence protocol for catalase was evidently faster, cheaper and provided reliable quantitative data that discriminated in the same way the compared groups. After this validation study, we recommend the use of catalase immunofluorescence as the first option for rapid screening of changes of the amount of hepatocytic peroxisomes, using their volume density as an indicator. Microsc. Res. Tech. 78:134-139, 2015. © 2014 Wiley Periodicals, Inc. PMID:25431324

Madureira, Tânia Vieira; Lopes, Célia; Malhão, Fernanda; Rocha, Eduardo



Identification, classification, and clinical relevance of catalase-negative, gram-positive cocci, excluding the streptococci and enterococci.  

PubMed Central

Several new genera and species of gram-positive, catalase-negative cocci that can cause infections in humans have been described. Although these bacteria were isolated in the clinical laboratory, they were considered nonpathogenic culture contaminants and were not thought to be the cause of any diseases. Isolation of pure cultures of these bacteria from normally sterile sites has led to the conclusion that these bacteria can be an infrequent cause of infection. This review describes the new bacteria and the procedures useful for clinical laboratories to aid in their identification. The clinical relevance and our experience with the various genera and species are reviewed and discussed. PMID:8665466

Facklam, R; Elliott, J A



Oxidative stress to DNA, protein, and antioxidant enzymes (superoxide dismutase and catalase) in rats treated with benzo( a)pyrene  

Microsoft Academic Search

Oxidative DNA damage (as 8-hydroxydeoxyguanosine; 8-OHdG), carbonyl content of proteins, and activities of superoxide dismutase (SOD) and catalase were investigated in female Sprague-Dawley rats orally treated with benzo(a)pyrene (B(a)P) (75 mg\\/rat). HPLC-ECD system showed that B(a)P increased the level of 8-OHdG in tissues (liver, kidney, and lung), but a statistical significance was observed only in the liver (3.5-fold increase) and

Kyu Bong Kim; Byung Mu Lee



Nutraceutical up-regulation of serotonin paradoxically induces compulsive behavior  

Technology Transfer Automated Retrieval System (TEKTRAN)

The role of diet in either the etiology or treatment of complex mental disorder is highly controversial in psychiatry. However, physiological mechanisms by which diet can influence brain chemistry – particularly that of serotonin – are well established. Here we show that dietary up-regulation of br...


Upregulation Of Interferon-Gamma-Induced Genes During Prion Infection  

Microsoft Academic Search

Global gene expression analysis allows for the identification of transcripts that are differentially regulated during a disease state. Many groups, including our own, have identified hundreds of genes differentially regulated in response to prion infection. Eleven transcripts, upregulated in the brains of prion-infected animals, which were classified in the literature as stimulated by the cytokine interferon-gamma (IFN-?), were identified. This

Laura R. Moody; Allen J. Herbst; Judd M. Aiken



ORIGINAL ARTICLE Upregulation of RASGRP3 expression in prostate cancer  

E-print Network

OPEN ORIGINAL ARTICLE Upregulation of RASGRP3 expression in prostate cancer correlates and tissues in BPH and prostate cancer (PCa), as well as its associations with cancer invasion and prognosis in prostate carcinomas. METHODS: Expression analysis of RasGRP3 was accomplished using immunohistochemical

Cai, Long


Upregulation of caveolin in multidrug resistant cancer cells: functional implications  

Microsoft Academic Search

Multidrug resistance (MDR) is a multifactorial process that involves elevated expression of drug transporters as well as additional biochemical changes that contribute to the drug resistant phenotype. Here we review recent results indicating the upregulation of constituents of rafts and caveolae, including glucosylceramide, cholesterol and caveolin-1, in MDR cells. Accordingly, the number of plasma membrane caveolae is greatly increased in

Yaakov Lavie; Giusy Fiucci; Mordechai Liscovitch



Influence of Foreign DNA Introduction and Periplasmic Expression of Recombinant Human Interleukin-2 on Hydrogen Peroxide Quantity and Catalase Activity in Escherichia coli  

PubMed Central

Purpose: Oxidative stress is generated through imbalance between composing and decomposing of reactive oxygen species (ROS). This kind of stress was rarely discussed in connection with foreign protein production in Escherichia coli. Effect of cytoplasmic recombinant protein expression on Hydrogen peroxide concentration and catalase activity was previously reported. In comparison with cytoplasm, periplasmic space has different oxidative environment. Therefore, in present study we describe the effect of periplasmic expression of recombinant human interleukin-2 (hIL-2) on H2O2 concentration and catalase activity in Escherichia coli and their correlation with cell growth. Methods: Having constructed pET2hIL2 vector, periplasmic expression of hIL-2 was confirmed. Then, H2O2 concentration and catalase activity were determined at various ODs. Wild type and empty vector transformed cells were used as negative controls. Results: It was shown that H2O2 concentration in hIL-2 expressing cells was significantly higher than its concentration in wild type and empty vector transformed cells. Catalase activity and growth rate reduced significantly in hIL-2 expressing cells compared to empty vector transformed and wild type cells. Variation of H2O2 concentration and catalase activity is intensive in periplasmic hIL-2 expressing cells than empty vector containing cells. Correlation between H2O2 concentration elevation and catalase activity reduction with cell growth depletion are also demonstrated. Conclusion: Periplasmic expression of recombinant hIL-2 elevates the host cell’s hydrogen peroxide concentration possibly due to reduced catalase activity which has consequent suppressive effect on growth rate. PMID:24312866

Mahmoudi Azar, Lena; Mehdizadeh Aghdam, Elnaz; Karimi, Farrokh; Haghshenas, Babak; Barzegari, Abolfazl; Yaghmaei, Parichehr; Hejazi, Mohammad Saeid



Spectral studies of intermediate species formed in one-electron reactions of bovine liver catalase at room and low temperatures. A comparison with peroxidase reactions.  


The reactions of native bovine catalase with superoxide and solvated electrons have been investigated using three different methods for generation of these reducing substrates: gamma-radiolysis of oxygenated or deaerated buffer solutions in the presence of an OH radical scavenger; either xanthine or acetaldehyde with xanthine oxidase; and low-temperature (77 K) gamma-radiolysis of buffered ethylene glycol/water solutions with subsequent annealing of samples at 183 K. The first spectral evidence for catalase compound II formation from native catalase via reaction with superoxide was obtained. The results are compared with results for peroxidase compound II or III formation observed under the same experimental conditions. A scheme is proposed to explain these observations involving intermediate formation of catalase compounds I and III and the ferrous enzyme. The one-electron reduction of catalase and peroxidase by radiolytically-generated solvated electrons was compared. In the present study the first absorption spectrum of a high-spin ferrous catalase which has peaks at 561 and 594 nm is reported, in comparison with a hemochromogen low-spin ferrous peroxidase observed under the same experimental conditions (peaks at 527 and 556 nm). Both spectra were recorded at 77 K. Data presented in this work also provide the first spectral evidence indicating the low temperature (183 K) conversion of high-spin ferrous catalase into compound III (oxycatalase) in the presence of dioxygen. Under the same experimental conditions low-spin ferrous peroxidase was converted into the high-spin ferrous form without oxyperoxidase formation. PMID:1361511

Metodiewa, D; Dunford, H B



Effect of compatible and noncompatible osmolytes on the enzymatic activity and thermal stability of bovine liver catalase.  


Catalase is an important antioxidant enzyme that catalyzes the disproportionation of H2O2 into harmless water and molecular oxygen. Due to various applications of the enzyme in different sectors of industry as well as medicine, the enhancement of stability of the enzyme is important. Effect of various classes of compatible as well as noncompatible osmolytes on the enzymatic activity, disaggregation, and thermal stability of bovine liver catalase have been investigated. Compatible osmolytes, proline, xylitol, and valine destabilize the denatured form of the enzyme and, therefore, increase its disaggregation and thermal stability. The increase in the thermal stability is accompanied with a slight increase of activity in comparison to the native enzyme at 25?°C. On the other hand, histidine, a noncompatible osmolyte stabilizes the denatured form of the protein and hence causes an overall decrease in the thermal stability and enzymatic activity of the enzyme. Chemometric results have confirmed the experimental results and have provided insight into the distribution and number of mole fraction components for the intermediates. The increase in melting temperature (Tm) and enzymatic rate could be further amplified by the intrinsic effect of temperature enhancement on the enzymatic activity for the industrial purposes. PMID:23249140

Sepasi Tehrani, H; Moosavi-Movahedi, A A; Ghourchian, H; Ahmad, F; Kiany, A; Atri, M S; Ariaeenejad, Sh; Kavousi, K; Saboury, A A



Specific binding and inhibition of 6-benzylaminopurine to catalase: multiple spectroscopic methods combined with molecular docking study.  


6-Benzylaminopurine (6-BA) is a kind of cytokinin which could regulate the activities of the antioxidant defense system of plants. In this work, its interaction with and inhibition of beef liver catalase have been systematically investigated using spectroscopic, isothermal titration calorimetric and molecular docking methods under physiological conditions. The fluorescence quenching of beef liver catalase (BLC) by 6-BA is due to the formation of 6-BA-BLC complex. Hydrogen bonds and van der Waals interactions play major roles in stabilizing the complex. The Stern-Volmer quenching constant, binding constant, the corresponding thermodynamic parameters and binding numbers were measured. The results of UV-vis absorption, three-dimensional fluorescence, synchronous fluorescence and circular dichroism spectroscopic results demonstrate that the binding of 6-BA results in the micro-environment change around tyrosine (Tyr) and tryptophan (Trp) residues of BLC. The BLC-mediated conversion of H2O2 to H2O and O2, in the presence and absence of 6-BA, was also studied. Lineweaver-Burk plot indicates a noncompetitive type of inhibition. Molecular docking study was used to find the binding sites. PMID:24412785

Xu, Qin; Lu, Yanni; Jing, Longyun; Cai, Lijuan; Zhu, Xinfeng; Xie, Ju; Hu, Xiaoya



Structural characterization of the Ser324Thr variant of the catalase-peroxidase (KatG) from Burkholderia pseudomallei.  


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. PMID:15567407

Deemagarn, Taweewat; Carpena, Xavier; Singh, Rahul; Wiseman, Ben; Fita, Ignacio; Loewen, Peter C



Mechanism of catalase activity in aqueous solutions of dimanganese(III,IV) ethylenediamine-N,N prime -diacetate  

SciTech Connect

Manganous ions, ligated by ethylenediamine-N,N{prime}-diacetate (edda = L) decompose hydrogen peroxide with a rate law {minus}d(H{sub 2}O{sub 2})/dt = k{sub 17}(Mn(edda))(H{sub 2}O{sub 2}) where k{sub 17} = 5.4 M{sup {minus}1} s{sup {minus}1} at pH 7. The reduction of peroxide to water is initiated by the reaction of Mn{sup II}L with a dinuclear Mn{sup III,IV}L{sub 2}. A subsequent fast reaction between the transient product of this reaction and hydrogen peroxide or tert-butyl hydroperoxide effectively oxidizes Mn(II) to Mn(IV) in a concerted step without formation of the hydroxyl radical. The green mixed-valence complex, which is probably a bis({mu}-oxo)-bridged structure, is stable in neutral aqueous solution and exhibits a 16-line ESR signal in frozen solution. The basis of catalase activity is the autocatalytic formation of this complex when hydrogen peroxide is reduced by manganese(II). The catalase cycle is independent of the formation of oxy radicals. Mononuclear Mn{sup III}edda and Mn{sup II}edda react with superoxide radicals, but the decomposition of peroxide is virtually independent of these reactions. In unbuffered solutions, with a moderate excess of hydrogen peroxide, an oscillation in the concentration of the dinuclear complex is detected. 28 refs., 10 figs., 5 tabs.

Rush, J.D.; Maskos, Z. (Louisiana State Univ., Baton Rouge (USA))




E-print Network

CENTER OF BACTERlAL CATALASE INVEST1GATED BY MOSSBAUER SPECTROSCOPY F. Parak, D. Bade and A.L. Yarie Max.- La catalase de Micrococcus luteus enrichie au 5 7 ~ ea Qtb etudibe en u t i l i s a n t l a spectros l o r s de mesures EPR. Les quatre sous-unitbs de l a catalase prbsentent un comportement identique

Paris-Sud XI, Université de


In vitro and in vivo inhibitory effects of some fungicides on catalase produced and purified from white-rot fungus Phanerochaete chrysosporium.  


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. PMID:24079700

Kavakç?o?lu, Berna; Tarhan, Leman



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

PubMed Central

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 ?g/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 dismutase in the treated cells could alter the antioxidant defense system, potentially contributing towards the anti-proliferative effect. There is great potential for the ethyl acetate extract of P. betle leaf as a source of natural antioxidants and to be developed as therapeutics in cancer treatment. PMID:23153283



Reactive oxygen species as second messengers? Induction of the expression of yeast catalase T gene by heat and hyperosmotic stress does not require oxygen.  


It is shown that oxygen is not absolutely needed for stress-induced synthesis of catalase T in the yeast Saccharomyces cerevisiae. Yeast cells develop heat resistance after exposure to elevated temperatures in anoxia. The levels of catalase activity and thermotolerance are comparable to those in aerobically stressed cells. While these results obviously do not exclude a stress signaling role of reactive oxygen species in some systems, as postulated by other authors, they suggest that the question of the obligatory requirement for reactive oxygen species in other stress signaling systems should be rigorously re-investigated. PMID:10961694

Krawiec, Z; Bili?ski, T; Schüller, C; Ruis, H



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

NASA Astrophysics Data System (ADS)

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.

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



Polymer-Induced Heteronucleation for Protein Single Crystal Growth: Structural Elucidation of Bovine Liver Catalase and Concanavalin A Forms  

SciTech Connect

Obtaining single crystals for X-ray diffraction remains a major bottleneck in structural biology; when existing crystal growth methods fail to yield suitable crystals, often the target rather than the crystallization approach is reconsidered. Here we demonstrate that polymer-induced heteronucleation, a powerful technique that has been used for small molecule crystallization form discovery, can be applied to protein crystallization by optimizing the heteronucleant composition and crystallization formats for crystallizing a wide range of protein targets. Applying these advances to two benchmark proteins resulted in dramatically increased crystal size, enabling structure determination, for a half century old form of bovine liver catalase (BLC) that had previously only been characterized by electron microscopy, and the discovery of two new forms of concanavalin A (conA) from the Jack bean and accompanying structural elucidation of one of these forms.

Foroughi, Leila M.; Kang, You-Na; Matzger, Adam J. (Michigan)



[Qualitative composition of carotenoids, catalase and superoxide dismutase activities in tissues of bivalve mollusc Anadara inaequivalvis (Bruguiere, 1789)].  


By using high-performance liquid chromatography, UV-VIS-spectra and mass spectra (FAB MS) in tissues of bivalve mollusc Anadara inaequivalvis (Bruguiere, 1789) there are identified seven kinds of carotenoids: trans- and cis-pectenolon, alloxanthin, pectenol A, beta-carotene, zeaxanthin, and diatoxanthin. Their quantitative ratio in hepatopancreas, gills, and foot of the animals was determined. There was revealed negative correlation (R2 about 0.9) between content of several carotenoids (trans- and cis-pectenolon, zeaxanthin, alloxanthin, and diatoxanthin) in tissues and activities of antioxidant enzymes (catalase and superoxide dismutase). The presence of competitive relations between these molecular systems is assumed and their underlying causes are discussed. PMID:24459858

Soldatov, A A; Gostiukhina, O L; Borodina, A V; Golovina, I V



Targeted expression of catalase to mitochondria prevents age-associated reductions in mitochondrial function and insulin resistance.  


Aging-associated muscle insulin resistance has been hypothesized to be due to decreased mitochondrial function, secondary to cumulative free radical damage, leading to increased intramyocellular lipid content. To directly test this hypothesis, we examined both in vivo and in vitro mitochondrial function, intramyocellular lipid content, and insulin action in lean healthy mice with targeted overexpression of the human catalase gene to mitochondria (MCAT mice). Here, we show that MCAT mice are protected from age-induced decrease in muscle mitochondrial function (?30%), energy metabolism (?7%), and lipid-induced muscle insulin resistance. This protection from age-induced reduction in mitochondrial function was associated with reduced mitochondrial oxidative damage, preserved mitochondrial respiration and muscle ATP synthesis, and AMP-activated protein kinase-induced mitochondrial biogenesis. Taken together, these data suggest that the preserved mitochondrial function maintained by reducing mitochondrial oxidative damage may prevent age-associated whole-body energy imbalance and muscle insulin resistance. PMID:21109199

Lee, Hui-Young; Choi, Cheol Soo; Birkenfeld, Andreas L; Alves, Tiago C; Jornayvaz, Francois R; Jurczak, Michael J; Zhang, Dongyan; Woo, Dong Kyun; Shadel, Gerald S; Ladiges, Warren; Rabinovitch, Peter S; Santos, Janine H; Petersen, Kitt F; Samuel, Varman T; Shulman, Gerald I



Targeted Expression of Catalase to Mitochondria Prevents Age-Associated Reductions in Mitochondrial Function and Insulin Resistance  

PubMed Central

SUMMARY Aging-associated muscle insulin resistance has been hypothesized to be due to decreased mitochondrial function, secondary to cumulative free radical damage, leading to increased intramyocellular lipid content. To directly test this hypothesis we examined both in vivo and in vitro mitochondrial function, intramyocellular lipid content and insulin action in lean healthy mice with targeted overexpression of the human catalase gene to mitochondria (MCAT mice). Here we show that MCAT mice are protected from age-induced decrease in muscle mitochondrial function (~30%), energy metabolism (~7%) and lipid-induced muscle insulin resistance. This protection from age-induced reduction in mitochondrial function was associated with reduced mitochondrial oxidative damage, preserved mitochondrial respiration and muscle ATP synthesis and AMP-activated protein kinase-induced mitochondrial biogenesis. Taken together these data suggest that the preserved mitochondrial function maintained by reducing mitochondrial oxidative damage may prevent age-associated whole body energy imbalance and muscle insulin resistance. PMID:21109199

Lee, Hui-Young; Choi, Cheol Soo; Birkenfeld, Andreas L.; Alves, Tiago C.; Jornayvaz, Francois R.; Jurczak, Michael J.; Zhang, Dongyan; Woo, Dong Kyun; Shadel, Gerald S.; Ladiges, Warren; Rabinovitch, Peter S.; Santos, Janine H.; Petersen, Kitt F.; Samuel, Varman T.; Shulman, Gerald I.



Protandim attenuates intimal hyperplasia in human saphenous veins cultured ex vivo via a catalase-dependent pathway  

Microsoft Academic Search

Human saphenous veins (HSVs) are widely used for bypass grafts despite their relatively low long-term patency. To evaluate the role of reactive oxygen species (ROS) signaling in intima hyperplasia (IH), an early stage pathology of vein-graft disease, and to explore the potential therapeutic effects of up-regulating endogenous antioxidant enzymes, we studied segments of HSV cultured ex vivo in an established

Binata Joddar; Rashmeet K. Reen; Michael S. Firstenberg; Saradhadevi Varadharaj; Joe M. McCord; Jay L. Zweier; Keith J. Gooch



Cigarette Smoke Upregulates Rat Coronary Artery Endothelin Receptors In Vivo  

PubMed Central

Background Cigarette smoking is a strong cardiovascular risk factor and endothelin (ET) receptors are related to coronary artery diseases. The present study established an in vivo secondhand smoke (SHS) exposure model and investigated the hypothesis that cigarette smoke induces ET receptor upregulation in rat coronary arteries and its possible underlying mechanisms. Methodology/Principal Findings Rats were exposed to SHS for 200 min daily for 8 weeks. The coronary arteries were isolated and examined. The vasoconstriction was studied by a sensitive myograph. The expression of mRNA and protein for receptors was examined by real-time PCR, Western blot and immunofluorescence. Compared to fresh air exposure, SHS increased contractile responses mediated by endothelin type A (ETA) and type B (ETB) receptors in coronary arteries. In parallel, the expression of mRNA and protein for ETA and ETB receptors of smoke exposed rats were higher than that of animals exposed to fresh air, suggesting that SHS upregulates ETA and ETB receptors in coronary arteries in vivo. Immunofluorescence staining showed that the enhanced receptor expression was localized to the smooth muscle cells of coronary arteries. The protein levels of phosphorylated (p)-Raf-1 and p-ERK1/2 in smoke exposed rats were significantly higher than in control rats, demonstrating that SHS induces the activation of the Raf/ERK/MAPK pathway. Treatment with Raf-1 inhibitor GW5074 suppressed SHS-induced enhanced contraction mediated by ETA receptors, and inhibited the elevated mRNA and protein levels of ETA and ETB receptors caused by SHS. The results of correlation and regression analysis showed that phosphorylation of Raf and ERK1/2 were independent determinants to affect protein expression of ETB and ETA receptors. Conclusions/Significance Cigarette smoke upregulates ETB and ETA receptors in rat coronary artery, which is associated with the activation of the Raf/ERK/MAPK pathway. PMID:22412974

Cao, Lei; Zhang, Yaping; Cao, Yong-Xiao; Edvinsson, Lars; Xu, Cang-Bao



VCP Is an integral component of a novel feedback mechanism that controls intracellular localization of catalase and H2O2 Levels.  


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. PMID:23457492

Murakami, Katsuhiro; Ichinohe, Yuzuru; Koike, Masaaki; Sasaoka, Norio; Iemura, Shun-ichiro; Natsume, Tohru; Kakizuka, Akira



Expression of multiple copies of mitochondrially targeted catalase or genomic Mn superoxide dismutase transgenes does not extend the life span of Drosophila melanogaster  

Microsoft Academic Search

The simultaneous overexpression of multiple copies of Mn superoxide dismutase (SOD) and ectopic catalase (mtCat) transgenes in the mitochondria of the fruit fly, Drosophila melanogaster, was shown previously to diminish the life span. The hypothesis tested in this study was that this effect was due primarily to the presence of one or the other transgene. An alternative hypothesis was that

Robin J. Mockett; Barbara H. Sohal; Rajindar S. Sohal



Access channel residues Ser315 and Asp137 in Mycobacterium tuberculosis catalase-peroxidase (KatG) control peroxidatic activation of the pro-drug isoniazid  

PubMed Central

Peroxidatic activation of the anti-tuberculosis pro-drug isoniazid by Mycobacterium tuberculosis catalase-peroxidase (KatG) is regulated by gating residues of a heme access channel. The steric restriction at the bottleneck of this channel is alleviated by replacement of residue Asp137 with Ser, according to crystallographic and kinetic studies. PMID:24185282

Zhao, Xiangbo; Hersleth, Hans-Petter; Zhu, Janan; Andersson, K. Kristoffer; Magliozzo, Richard S.



Copper and Zinc-containing Superoxide Dismutase, Manganese-containing Superoxide Dismutase, Catalase, and Glutathione Peroxidase in Normal and Neoplastic Human Cell Lines and Normal Human Tissues1  

Microsoft Academic Search

Copper- and zinc-containing Superoxide dismutase, man ganese-containing Superoxide dismutase, catalase, and gluta- thione peroxidase form the primary enzymic defense against toxic oxygen reduction metabolites. Such metabolites have been implicated in the damage brought about by ionizing radiation, as well as in the effects of several cytostatic com pounds. These enzymes were analyzed in 31 different human normal diploid and neoplastic

Stefan L. Marklund; N. Gunnar Westman; Erik Lundgren; Goran Roos


Green tea catechin induced phagocytosis can be blocked by catalase and an inhibitor of transient receptor potential melastatin 2 (TRPM2).  


The major polyphenols in green tea, (-)-epigallocatechin and (-)-epigallocatechin gallate, have been shown to enhance the phagocytic activity of macrophage-like cells; however, the mechanism involved was not clarified. In this study, we have identified that the catechins induced phagocytosis can be blocked by catalase and an inhibitor of transient receptor potential melastatin 2. PMID:23896702

Monobe, Manami; Ema, Kaori; Tokuda, Yoshiko; Maeda-Yamamoto, Mari



Linear-transform and non-linear modelling of bovine milk catalase inactivation in a high-temperature short-time pasteurizer  

Microsoft Academic Search

Milk for cheese manufacture is commonly heated at temperatures in the range 63–65 °C for about 15 s to reduce bacterial numbers. These heat treatments have been referred to as thermization. There is no good method for determining whether a milk has undergone a heat treatment equivalent to thermization, although it has been suggested that inactivation of milk catalase is

Y. Hirvi; M. W. Griffiths; R. C. McKellar; H. W. Modler



Role of reactive oxygen species in the signalling cascade of cyclosporine A-mediated up-regulation of eNOS in vascular endothelial cells  

PubMed Central

Cyclosporine?A (CsA) increases eNOS mRNA expression in bovine cultured aortic endothelial cells (BAEC). As some effects of CsA may be mediated by reactive oxygen species (ROS), present experiments were devoted to test the hypothesis that the CsA-induced eNOS up-regulation could be dependent on an increased synthesis of ROS.CsA induced a dose-dependent increase of ROS synthesis, with the two fluorescent probes used, DHR123 (CsA 1??M: 305±7% over control) and H2DCFDA (CsA 1??M: 178±6% over control).Two ROS generating systems, xanthine plus xanthine oxidase (XXO) and glucose oxidase (GO), increased the expression of eNOS mRNA in BAEC, an effect which was maximal after 8?h of incubation (XXO: 168±21% of control values. GO: 208±18% of control values). The ROS-dependent increased eNOS mRNA expression was followed by an increase in eNOS activity.The effect of CsA on eNOS mRNA expression was abrogated by catalase, and superoxide dismutase (SOD). In contrast, the antioxidant PDTC augmented eNOS mRNA expression, both in basal conditions and in the presence of CsA.The potential participation of the transcription factor AP-1 was explored. Electrophoretic mobility shift assays were consistent with an increase in AP-1 DNA-binding activity in BAEC treated with CsA or glucose oxidase.The present results support a role for ROS, particularly superoxide anion and hydrogen peroxide, as mediators of the CsA-induced eNOS mRNA up-regulation. Furthermore, they situate ROS as potential regulators of gene expression in endothelial cells, both in physiological and pathophysiological situations. PMID:9647467

López-Ongil, S; Hernández-Perera, O; Navarro-Antolín, J; Pérez de Lema, G; Rodríguez-Puyol, M; Lamas, S; Rodríguez-Puyol, D



Three-Dimensional Model and Molecular Mechanism of Mycobacterium tuberculosis Catalase-Peroxidase (KatG) and Isoniazid-Resistant KatG Mutants  

PubMed Central

Mycobacterium tuberculosis KatG enzyme functions both as catalase for removing hydrogen peroxide (H2O2) and as peroxidase for oxidating isoniazid (INH) to active form of anti-tuberculosis drug. Although mutations in M. tuberculosis KatG confer INH resistance in tuberculous patients, structural bases for INH-resistant mutations in the KatG gene remains poorly understood. Here, three M. tuberculosis KatG mutants bearing Arg418? Gln, Ser315 ? Thr, or Trp321 ? Gly replacement were assessed for changes in catalase-peroxidase activities and possible structure bases relevant to such changes. These three M. tuberculosis KatG mutants exhibited a marked impairment or loss of catalase-peroxidase activities. The possible structural bases for the mutant-induced loss of enzyme activities were then analyzed using a three-dimensional model of M. tuberculosis KatG protein constructed on the basis of the crystal structure of the catalase-peroxidase from Burkholderia pseudomallei. The model suggests that three M. tuberculosis KatG mutants bearing Arg418 ? Gln, Ser315 ? Thr, or Trp321 ? Gly replacement affect enzyme activities by different mechanisms, although each of them impacts consequently on a heme-associated structure, the putative oxidative site. Moreover, in addition to the widely accepted substrate-binding site, M. tuberculosis KatG may bear another H2O2 binding site. This H2O2 binding site appears to interact with the catalytic site by a possible electron-transfer chain, a Met255-Tyr229-Trp107 triad conserved in many catalase-peroxidases. The Ser315 ? Thr mutant may have direct effect on the catalytic site by interfering with electron transfer in addition to the previously proposed mechanism of steric constraint. PMID:15650370

Mo, L.; Zhang, W.; Wang, J.; Weng, X.H.; Chen, S.; Shao, L.Y.; Pang, M.Y.; Chen, Z.W.



Pesticide/herbicide pollutants in the Kafue River and a preliminary investigation into their biological effect through catalase levels in fish.  


The study determined the types of pesticide/herbicide pollutants in water, sediment and fish from the Kafue River. A preliminary investigation of the oxidative stress from these pesticides/herbicides was also assessed by measurement of catalase activity. Water, sediment and fish samples were collected upstream, midstream and downstream the Kafue river in Chingola, Kitwe, Kafue National Park and Kafue Town. Water, sediment and fish muscle were sampled and analysed for pesticides using Gas chromatography. For catalase activity fish liver samples only were examined. The pesticides/herbicides detected in all samples collectively included: Heptachlor, pp'-DDE, Cypermethrin, Chlordane, Toxaphene, Terbufos, Kelthane, Endosulfan, Dieldrin, pp'-DDD, pp'-DDT, Atrazine, Disulfoton, d-trans-Allethrin and Endrin. On the other hand, catalase activity was detected in all fish liver samples from all sites. Its levels increased significantly from Chingola upstream to sites downstream with highest being in Kafue town. This study therefore, demonstrates that there is widespread contamination of the Kafue River with pesticides/ herbicides. It also demonstrates that organochlorides are found throughout the river especially in fish samples. The spectrum of pesticides/herbicides was much wider in fish probably due to bioaccumulation. It was also observed that fish are subjected to oxidative stress as determined by catalase levels. The stress is more pronounced downstream where the catalase levels were significantly higher than Chingola. The observation that more pesticide varieties are also found downstream may suggest a likely causative effect of the pesticides on oxidative stress although this needs further investigation. This study further tentatively highlights the potential dangers of these agro-related substances to dependants of the Kafue River water body and the need to carry out risk assessments and thereafter institute corrective measures to help reduce contamination and adverse effects. PMID:17201197

Syakalima, Michelo; Choongo, Kennedy; Mwenechanya, Roy; Wepener, Victor; Yamasaki, Masahiro; Maede, Yoshimitsu



Purification and Characterization of a Mycelial Catalase from Scedosporium boydii, a Useful Tool for Specific Antibody Detection in Patients with Cystic Fibrosis.  


Scedosporium boydii is an opportunistic filamentous fungus which may be responsible for a wide variety of infections in 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) and may lead to allergic bronchopulmonary mycoses, sensitization, or respiratory infections. Upon microbial infection, host phagocytic cells release reactive oxygen species (ROS), such as hydrogen peroxide, as part of the antimicrobial response. Catalases are known to protect pathogens against ROS by detoxification of the hydrogen peroxide. Here, we investigated the catalase equipment of Scedosporium boydii, one of the major pathogenic species in the S. apiospermum species complex. Three catalases were identified, and the mycelial catalase A1 was purified to homogeneity by a three-step chromatographic process. This enzyme is a monofunctional tetrameric protein of 460 kDa, consisting of four 82-kDa glycosylated subunits. The potential usefulness of this enzyme in serodiagnosis of S. apiospermum infections was then investigated by an enzyme-linked immunosorbent assay (ELISA), using 64 serum samples from CF patients. Whatever the species involved in the S. apiospermum complex, sera from infected patients were clearly differentiated from sera from patients with an Aspergillus fumigatus infection or those from CF patients without clinical and biological signs of a fungal infection and without any fungus recovered from sputum samples. These results suggest that catalase A1 is a good candidate for the development of an immunoassay for serodiagnosis of infections caused by the S. apiospermum complex in patients with CF. PMID:25355796

Mina, Sara; Marot-Leblond, Agnès; Cimon, Bernard; Fleury, Maxime J J; Larcher, Gérald; Bouchara, Jean-Philippe; Robert, Raymond



Upregulation of BST-2/Tetherin by HIV Infection In Vivo ? §  

PubMed Central

The interferon-inducible antiviral factor BST-2 prevents several enveloped viruses, including HIV, from escaping infected cells. The HIV protein Vpu antagonizes this host defense. Little is known about the expression of BST-2 during HIV infection in vivo and whether it can be modulated to the host's advantage. We studied the expression of BST-2 on blood cells from HIV-infected patients during the acute and chronic phases of disease as well as after antiretroviral treatment (ART). The expression of BST-2 was increased on mononuclear leukocytes, including CD4-positive T lymphocytes from HIV-positive patients, compared to that on cells of uninfected controls. The expression of BST-2 was highest during acute infection and decreased to levels similar to those of uninfected individuals after ART. Treatment of primary blood mononuclear cells in vitro with alpha interferon or with Toll-like receptor (TLR) agonists increased the expression of BST-2 to levels similar to those found during infection in vivo. The interferon-induced levels were sufficient to overcome the Vpu protein in vitro, reducing the release of wild-type HIV. These data show that BST-2 is upregulated during HIV infection, consistent with its role as an interferon-stimulated gene. The data further suggest that this upregulation is sufficient to saturate the activity of Vpu and inhibit wild-type HIV. PMID:21849457

Homann, Stefanie; Smith, Davey; Little, Susan; Richman, Douglas; Guatelli, John



Involvement of Prohibitin Upregulation in Abrin-Triggered Apoptosis  

PubMed Central

Abrin (ABR), a protein purified from the seeds of Abrus precatorius, induces apoptosis in various types of cancer cells. However, the detailed mechanism remains largely uncharacterized. By using a cDNA microarray platform, we determined that prohibitin (PHB), a tumor suppressor protein, is significantly upregulated in ABR-triggered apoptosis. ABR-induced upregulation of PHB is mediated by the stress-activated protein kinase/c-Jun NH2-terminal kinase (SAPK/JNK) pathway, as demonstrated by chemical inhibitors. In addition, ABR significantly induced the expression of Bax as well as the activation of caspase-3 and poly(ADP-ribose) polymerase (PARP) in Jurkat T cells, whereas the reduction of PHB by specific RNA interference delayed ABR-triggered apoptosis through the proapoptotic genes examined. Moreover, our results also indicated that nuclear translocation of the PHB-p53 complex may play a role in the transcription of Bax. Collectively, our data show that PHB plays a role in ABR-induced apoptosis, which may be helpful for the development of diagnostic or therapeutic agents. PMID:21961024

Liu, Yu-Huei; Peck, Konan; Lin, Jung-Yaw



Upregulation of Relaxin after Experimental Subarachnoid Hemorrhage in Rabbits  

PubMed Central

Background. Although relaxin causes vasodilatation in systemic arteries, little is known about its role in cerebral arteries. We investigated the expression and role of relaxin in basilar arteries after subarachnoid hemorrhage (SAH) in rabbits. Methods. Microarray analysis with rabbit basilar artery RNA was performed. Messenger RNA expression of relaxin-1 and relaxin/insulin-like family peptide receptor 1 (RXFP1) was investigated with quantitative RT-PCR. RXFP1 expression in the basilar artery was investigated with immunohistochemistry. Relaxin concentrations in cerebrospinal fluid (CSF) and serum were investigated with an enzyme-linked immunosorbent assay. Using human brain vascular smooth muscle cells (HBVSMC) preincubated with relaxin, myosin light chain phosphorylation (MLC) was investigated with immunoblotting after endothelin-1 stimulation. Results. After SAH, RXFP1 mRNA and protein were significantly downregulated on day 3, whereas relaxin-1 mRNA was significantly upregulated on day 7. The relaxin concentration in CSF was significantly elevated on days 5 and 7. Pretreatment with relaxin reduced sustained MLC phosphorylation induced by endothelin-1 in HBVSMC. Conclusion. Upregulation of relaxin and downregulation of RXFP1 after SAH may participate in development of cerebral vasospasm. Downregulation of RXFP1 may induce a functional decrease in relaxin activity during vasospasm. Understanding the role of relaxin may provide further insight into the mechanisms of cerebral vasospasm. PMID:25133183

Kikkawa, Yuichiro; Matsuo, Satoshi; Kurogi, Ryota; Nakamizo, Akira; Mizoguchi, Masahiro; Sasaki, Tomio



HCV infection induces the upregulation of miR-221 in NF-?B dependent manner.  


The upregulation of miR-221 has been reported in variety of cancer, including HCV associated HCC, the mechanism of upregulation of miR-221 however remains unclear. In this study, it was found that miR-221 was significantly upregulated in serum of patients with HCV associated chronic hepatitis (cHCV), which suggested the possible biological significance of miR-221 in HCV infection. Important, the upregulated miR-221 was positive correlation with serum miR-122, alanine aminotransferase (ALT) and aspartate transaminase (AST), which are reported as biomarkers for liver injuries. Further studies indicated that HCVcc infection activated nuclear factor-kappa B (NF-?B) and the upregulation of miR-221 by HCVcc infection could totally blocked by NF-?B inhibitor (pyrrolidine dithiocarbamate, PDTC). In conclusion, HCVcc infection could upregulate the expression of miR-221 in NF-?B dependent manner. PMID:25433287

Ding, Cui-Ling; Xu, Gang; Ren, Hao; Zhao, Lan-Juan; Zhao, Ping; Qi, Zhong-Tian; Wang, Wen



Mitochondrial electron transport chain complexes, catalase and markers of oxidative stress in platelets of patients with severe aluminum phosphide poisoning.  


Aluminum phosphide (ALP), a widely used fumigant and rodenticide, leads to high mortality if ingested. Its toxicity is due to phosphine that is liberated when it comes in contact with moisture. The exact site or mechanism of action of phosphine is not known, although it is widely believed that it affects mitochondrial oxidative phosphorylation. Basic serum biochemical parameters, activity of mitochondrial complexes, antioxidant enzymes and parameters of oxidative stress were estimated in the platelets of 21 patients who developed severe poisoning following ALP ingestion. These parameters were compared with 32 healthy controls and with 22 patients with shock due to other causes (cardiogenic shock (11), septic shock (9) and hemorrhagic shock (2)). The serum levels of creatine kinase-muscle brain and lactate dehydrogenase were higher in patients poisoned with ALP, whereas a significant decrease was observed in the activities of mitochondrial complexes I, II and IV. The activity of catalase was lower but the activities of superoxide dismutase and glutathione peroxidase were unaffected in them. A significant increase in lipid peroxidation and protein carbonylation was observed, whereas total blood thiol levels were lower. In patients severely poisoned with ALP, not only cytochrome c oxidase but also other complexes are involved in mitochondrial electron transport, and enzymes are also inhibited. PMID:23821638

Anand, R; Sharma, D R; Verma, D; Bhalla, A; Gill, K D; Singh, S



Evaluation of the serum catalase and myeloperoxidase activities in chronic arsenic-exposed individuals and concomitant cytogenetic damage  

SciTech Connect

Chronic arsenic exposure through contaminated drinking water is a major environmental health issue. Chronic arsenic exposure is known to exert its toxic effects by a variety of mechanisms, of which generation of reactive oxygen species (ROS) is one of the most important. A high level of ROS, in turn, leads to DNA damage that might ultimately culminate in cancer. In order to keep the level of ROS in balance, an array of enzymes is present, of which catalase (CAT) and myeloperoxidase (MPO) are important members. Hence, in this study, we determined the activities of these two enzymes in the sera and chromosomal aberrations (CA) in peripheral blood lymphocytes in individuals exposed and unexposed to arsenic in drinking water. Arsenic in drinking water and in urine was used as a measure of exposure. Our results show that individuals chronically exposed to arsenic have significantly higher CAT and MPO activities and higher incidence of CA. We found moderate positive correlations between CAT and MPO activities, induction of CA and arsenic in urine and water. These results indicate that chronic arsenic exposure causes higher CAT and MPO activities in serum that correlates with induction of genetic damage. We conclude that the serum levels of these enzymes might be used as biomarkers of early arsenic exposure induced disease much before the classical dermatological symptoms of arsenicosis begin to appear.

Banerjee, Mayukh; Banerjee, Nilanjana; Ghosh, Pritha [Molecular and Human Genetics Division, Indian Institute of Chemical Biology, Kolkata (India); Das, Jayanta K. [Department of Dermatology, West Bank Hospital, Howrah (India); Basu, Santanu [Department of General Medicine, Sri Aurobindo Seva Kendra, Kolkata (India); Sarkar, Ajoy K. [Peerless Hospital and B.K Roy Research Centre, Kolkata (India); States, J. Christopher, E-mail: jcstates@louisville.ed [Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY (United States); Center for Environmental Genomics and Integrative Biology, University of Louisville, Louisville, KY (United States); Giri, Ashok K., E-mail: [Molecular and Human Genetics Division, Indian Institute of Chemical Biology, Kolkata (India)



Manganese(II) induces cell division and increases in superoxide dismutase and catalase activities in an aging deinococcal culture  

SciTech Connect

Addition of Mn(II) at 2.5 microM or higher to stationary-phase cultures of Deinococcus radiodurans IR was found to trigger at least three rounds of cell division. This Mn(II)-induced cell division (Mn-CD) did not occur when the culture was in the exponential or death phase. The Mn-CD effect produced daughter cells proportionally reduced in size, pigmentation, and radioresistance but proportionally increased in activity and amount of the oxygen toxicity defense enzymes superoxide dismutase and catalase. In addition, the concentration of an Mn-CD-induced protein was found to remain high throughout the entire Mn-CD phase. It was also found that an untreated culture exhibited a growth curve characterized by a very rapid exponential-stationary transition and that cells which had just reached the early stationary phase were synchronous. Our results suggest the presence of an Mn(II)-sensitive mechanism for controlling cell division. The Mn-CD effect appears to be specific to the cation Mn(II) and the radioresistant bacteria, deinococci.

Chou, F.I.; Tan, S.T. (National Tsing Hua Univ., Taiwan (China))



Purification of recombinant catalase-peroxidase HPI from E. coli and its application in enzymatic polymerization reactions.  


In this paper, a recombinant catalase-peroxidase HPI from Escherichia coli was prepared, purified, and used in enzymatic polymerization reactions for the production of several oligomeric products. We tested the enzyme on four different substrates, chosen as representative of phenols and anilines: phenol, 3-methoxyphenol, catechol, and aniline. The polymerization reactions were followed by SEC-HPLC analysis, and except for aniline, all the other substrates were completely converted into one or more polymerization products. Results showed that reactions performed with phenol and 3-methoxyphenol allowed the isolation of some oligomers of different weight: a 27-monomeric unit oligomer and a 23-U oligomer are the heaviest ones. Experiments performed with catechol showed the formation of oligomers of 7 U in the reaction with HPI. HPI polymerization reactions performed with aniline allowed the identification of two different oligomers, one of 4 U and one of 10 U. All the substrates have been also used in reactions catalyzed by HRP in the same reaction conditions. Several products were common to the two enzymes. This work suggests the use of HPI as an alternative enzyme in peroxidatic reactions for the production of different oligomers from phenols and other compounds. PMID:23653125

Di Gennaro, Patrizia; Bargna, Anna; Bruno, Ferdinando; Sello, Guido



Catalase mimic property of Co3O4 nanomaterials with different morphology and its application as a calcium sensor.  


The applications of inorganic nanomaterials as biomimetic catalysts are receiving much attention because of their high stability and low cost. In this work, Co3O4 nanomaterials including nanoplates, nanorods, and nanocubes were synthesized. The morphologies and compositions of the products were characterized by scanning electron microscopy, transmission electron microscopy, and X-ray diffraction. The catalytic properties of Co3O4 nanomaterials as catalase mimics were studied. The Co3O4 materials with different morphology exhibited different catalytic activities in the order of nanoplates > nanorods > nanocubes. The difference of the catalytic activities originated from their different abilities of electron transfer. Their catalytic activities increased significantly in the presence of calcium ion. On the basis of the stimulation by calcium ion, a biosensor was constructed by Co3O4 nanoplates for the determination of calcium ion. The biosensor had a linear relation to calcium concentrations and good measurement correlation between 0.1 and 1 mM with a detection limit of 4 ?M (S/N = 3). It showed high selectivity against other metal ions and good reproducibility. The proposed method was successfully applied for the determination of calcium in a milk sample. PMID:24796855

Mu, Jianshuai; Zhang, Li; Zhao, Min; Wang, Yan



In Vitro Effect of Sodium Fluoride on Malondialdehyde Concentration and on Superoxide Dismutase, Catalase, and Glutathione Peroxidase in Human Erythrocytes  

PubMed Central

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??g/mL) or NaF (100??g/mL) + vitamin E (1, 2.5, 5 and 10??g/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. PMID:24223512

Gutiérrez-Salinas, José; García-Ortíz, Liliana; Morales González, José A.; Hernández-Rodríguez, Sergio; Ramírez-García, Sotero; Núñez-Ramos, Norma R.; Madrigal-Santillán, Eduardo



Evaluation of thermal acclimation capacity in corals with different thermal histories based on catalase concentrations and antioxidant potentials.  


Colonies of Pocillopora damicornis from Kaneohe Bay and colonies of Pocillopora meandrina from a thermal outfall site and a control site at Kahe were exposed to three different temperatures (29, 32 and 33 degrees C) in outdoor aquaria on running water tables for five days. Samples (n=3) were taken from each treatment at 0800, 1200 and 1600 h. ELISAs using catalase antibodies and ferric reducing/antioxidant potential (FRAP) assays were run on the samples to determine how antioxidant levels changed throughout the experiment. Light levels during the experiment were highest in the morning ( approximately 1000-1500 micromol quanta m(-2) s(-1)) and decreased to 25-60 micromol quanta m(-2) s(-1) by 1100 h and remained low until sunset. Antioxidant concentrations were highest in the morning for P. damicornis from Kaneohe and P. meandrina outfall samples. There was no significant change through the day for P. meandrina samples from the control site. The difference in response between the outfall samples and the control samples suggests that P. meandrina has acclimated to elevated temperatures found at the outfall site. PMID:16580241

Griffin, Sean P; Bhagooli, Ranjeet; Weil, Ernesto



Use of superoxide dismutase and catalase producing lactic acid bacteria in TNBS induced Crohn's disease in mice.  


Reactive oxygen species are involved in various aspects of intestinal inflammation and tumor development. Decreasing their levels using antioxidant enzymes, such as catalase (CAT) or superoxide dismutase (SOD) could therefore be useful in the prevention of certain diseases. Lactic acid bacteria (LAB) are ideal candidates to deliver these enzymes in the gut. In this study, the anti-inflammatory effects of CAT or SOD producing LAB were evaluated using a trinitrobenzenesulfonic acid (TNBS) induced Crohn's disease murine model. Engineered Lactobacillus casei BL23 strains producing either CAT or SOD, or the native strain were given to mice before and after intrarectal administration of TNBS. Animal survival, live weight, intestinal morphology and histology, enzymatic activities, microbial translocation to the liver and cytokines released in the intestinal fluid were evaluated. The mice that received CAT or SOD-producing LAB showed a faster recovery of initial weight loss, increased enzymatic activities in the gut and lesser extent of intestinal inflammation compared to animals that received the wild-type strain or those that did not receive bacterial supplementation. Our findings suggest that genetically engineered LAB that produce antioxidant enzymes could be used to prevent or decrease the severity of certain intestinal pathologies. PMID:21167883

LeBlanc, Jean Guy; del Carmen, Silvina; Miyoshi, Anderson; Azevedo, Vasco; Sesma, Fernando; Langella, Philippe; Bermúdez-Humarán, Luis G; Watterlot, Laurie; Perdigon, Gabriela; de Moreno de LeBlanc, Alejandra



Spectroscopic investigations on the effect of N-Acetyl-L-cysteine-Capped CdTe Quantum Dots on catalase  

NASA Astrophysics Data System (ADS)

Quantum dots (QDs) are recognized as some of the most promising semiconductor nanocrystals in biomedical applications. However, the potential toxicity of QDs has aroused wide public concern. Catalase (CAT) is a common enzyme in animal and plant tissues. For the potential application of QDs in vivo, it is important to investigate the interaction of QDs with CAT. In this work, the effect of N-Acetyl-L-cysteine-Capped CdTe Quantum Dots with fluorescence emission peak at 612 nm (QDs-612) on CAT was investigated by fluorescence, synchronous fluorescence, fluorescence lifetime, ultraviolet-visible (UV-vis) absorption and circular dichroism (CD) techniques. Binding of QDs-612 to CAT caused static quenching of the fluorescence, the change of the secondary structure of CAT and the alteration of the microenvironment of tryptophan residues. The association constants K were determined to be K288K = 7.98 × 105 L mol-1 and K298K = 7.21 × 105 L mol-1. The interaction between QDs-612 and CAT was spontaneous with 1:1 stoichiometry approximately. The CAT activity was also inhibited for the bound QDs-612. This work provides direct evidence about enzyme toxicity of QDs-612 to CAT in vitro and establishes a new strategy to investigate the interaction between enzyme and QDs at a molecular level, which is helpful for clarifying the bioactivities of QDs in vivo.

Sun, Haoyu; Yang, Bingjun; Cui, Erqian; Liu, Rutao



Effects of hydrogen peroxide on the motility, catalase and superoxide dismutase of dam and/or seqA mutant of Salmonella typhimurium.  


In addition to their role in the virulence attenuation of Salmonella and other pathogens, dam or seqA genes increase the sensitivity towards hydrogen peroxide. The aim of our study is to investigate the effect of H(2)O(2) on the motility, the catalase and superoxide dismutase activities of dam and/or seqA mutants of Salmonella typhimurium. Our findings showed significant differences of the effects of H(2)O(2) on the motility between wild type strain and all of mutants. Hydrogen peroxide changes SOD isoenzyme profile of these mutants by disappearance of Fe-SOD. Concerning the catalase, an increase of its activity was observed in the wild type, dam and seqA mutant. However, H(2)O(2) decreases the activity of this enzyme in the double mutant strain. We can suggest that the dam gene, together with seqA, play a protective role in the oxidative stress response of Salmonella typhimurium. PMID:22806788

Chatti, Abdelwaheb; Messaoudi, Nadia; Mihoub, Mouadh; Landoulsi, Ahmed



[Change in the content of salicylic acid and activities of phenylalanine ammonia-lyase and catalase in wheat seedling roots under the influence of Azospirilium lectins].  


The time course of changes in the endogenous content of salicylic acid, the ratio between the acid's free and bound forms, and changes in the activities of phenylalanine ammonia-lyase and catalase in wheat seedling roots under the effect of lectins of two strains of the associative nitrogen-fixing bacterium Azospirillum (A. brasilense Sp7 and its mutant defective in lectin activity, A. brasilense Sp7.2.3) is investigated. Differences in plant response to the action of the lectins from these two strains are established. On the basis of the obtained data, a model is proposed for lectin-assisted induction of resistance, according to which the lectin effect on the roots of seedlings results in the accumulation of free salicylic acid, which inhibits catalase activity, ultimately leading to accumulation of hydrogen peroxide and formation of induced resistance. PMID:25518563



Genetic studies of water buffalo blood markers. I. Red cell acid phosphatase, albumin, catalase, red cell ?-esterase-3, group-specific component, and protease inhibitor  

Microsoft Academic Search

We have developed the methodologies for typing and family studies to establish the modes of inheritance of water buffalo red cell acid phosphatase (Acp), protease inhibitor (Pi), and group-specific component (Gc) on isoelectric focusing and albumin (Alb), red cell a-esterase-3 (Est-3), and catalase (Cat) on polyacrylamide gel electrophoresis. Family studies showed that Pi, Gc, Alb, and Cat are coded by

S. G. Tan; J. S. F. Barker; O. S. Selvaraj; T. K. Mukherjee; Y. F. Wong



Role of glutathione redox cycle and catalase in defense against oxidative stress induced by endosulfan in adrenocortical cells of rainbow trout ( Oncorhynchus mykiss)  

Microsoft Academic Search

The role of antioxidants in maintaining the functional integrity of adrenocortical cells during in vitro exposure to endosulfan, an organochlorine pesticide, was investigated in rainbow trout (Oncorhynchus mykiss). Aminotriazole (ATA), an inhibitor of catalase (CAT), l-buthionine sulfoximine (l-BSO), an inhibitor of glutathione (GSH) synthesis, and N-acetyl cysteine (NAC), a glutathione precursor, were used to investigate the role of CAT and

J. Dorval; A. Hontela



The effects of temperature and pH on the kinetics of reactions between catalase and its suicide substrate hydrogen peroxide.  


Variation of initial (intact) activity (ai), inactivation rate constant (ki) and the partition ratio (r) of bovine liver catalase in the reaction with its suicide substrate, hydrogen peroxide, were determined in workable ranges of temperature (17-42 degrees C) or pH (5-10.5), using the data of progress curves. The changes of temperature had a slight effect on ai, giving a Q10 of 1.15 for the enzymatic breakdown of H2O2, corresponding to an improved value for its activation energy of 8.8 +/- l kJ.mol-1. In contrast, the ki was greatly increased by elevation of temperature, giving a Q10 of 2.1 for the suicide inactivation reaction of catalase. Consequently, a significant decrease of r was observed by increasing of temperature. In pH studies, decreasing of pH from 7.0 to 5.0 led to reduction of ai whereas the ki value was not effected significantly, possibly due to the parallel changes in affinities to free catalase and compound I for H2O2. Reduction of ki and alpha i were observed at pH > 9.5, where reversible dissociation of tetrameric enzyme into catalytically inactive subunits is possible. The r had a maximum value at pH around 7.5, similar to that of catalase activity. The effect of ionic strength on the above kinetic parameters was studied. There was not an observable influence when the ammonium sulfate concentration was below l M. PMID:9541866

Ghadermarzi, M; Moosavi-Movahedi, A A



Inhibition of mitogen-activated protein kinase pathway can induce upregulation of human leukocyte antigen class I without PD-L1-upregulation in contrast to interferon-? treatment.  


Recently, we reported that human leukocyte antigen (HLA) class I expression is predominantly regulated by the mitogen-activated protein kinase (MAPK) pathway as one of the oncogenic regulations of HLA class I expression. In the present study, we examined mechanisms of how HLA class I and PD-L1 are regulated by MAPK inhibitors and interferon-? (IFN-?). Furthermore, we evaluated the expression of major signal transduction molecules by Western blot and anti-tumor CTL activity by a cytotoxic assay when HLA class I and PD-L1 were modulated by MAPK inhibitors and/or IFN-?. As a result, we confirmed, as a more general phenomenon, that the inhibition of MAPK could upregulate HLA class I expression in a panel of human solid tumors (n = 26). Of note, we showed that MAPK inhibitors act on the upregulation of HLA class I expression through a different pathway from IFN-?; there was an additive effect in the upregulation of HLA class I when treated with the combination of MAPK inhibitors and IFN-?, and there was no overlapping activation of JAK2/STAT1 and Erk1/2 molecules when treated with either IFN-? or MAPK inhibitors. Furthermore, we showed that IFN-?-treatment impaired the tumor-specific CTL activity due to the upregulation of PD-L1 in spite of the upregulation of HLA class I, while MAPK inhibitors can augment the tumor-specific CTL activity due to the upregulated HLA class I without PD-L1 alterations. In conclusion, in addition to the original anti-proliferative activity, MAPK inhibitors may work toward the enhancement of T-cell-mediated anti-tumor immunity through the upregulation of HLA class I without the upregulation of PD-L1. PMID:25154680

Mimura, Kousaku; Kua, Ley-Fang; Shiraishi, Kensuke; Kee Siang, Lim; Shabbir, Asim; Komachi, Mayumi; Suzuki, Yoshiyuki; Nakano, Takashi; Yong, Wei-Peng; So, Jimmy; Kono, Koji



Combination of laccase and catalase in construction of H2O2-O2 based biocathode for applications in glucose biofuel cells.  


In this study, we propose a new strategy to boost the power density of glucose biofuel cells (GBFCs) biocathodes. By combining laccase with catalase enzymes electrophoretically deposited by means of AC electric fields on multiple walled carbon nanotubes modified platinum black and, then stabilized by an outer layer of polypyrrole in the construction of GC/MWCNTs/Ptb/LAc-CAt/PPy biocathode, we can take advantage of the H(2)O(2) present in the solution or body tissue to increase the level of the dissolved O(2). The results from cyclic voltammetry, amperometry and electrochemical impedance spectroscopy demonstrate that the deposited enzymes laccase and catalase by means of AC-EPD did not inhibit each other and carry out ?90% of the catalytic reduction process of O(2)-H(2)O(2). The power density of the non-compartmentalized GBFC constructed from GC/MWCNTs/Ptb/LAc-CAt/PPy biocathode and GC/MWCNTs/GOx/PPy bioanode in phosphate buffer containing 10mM glucose and equal amounts of dissolved O(2) and H(2)O(2) (0.3mM) is almost doubled because of the presence of catalase enzyme in the constructed biocathode. The latter might be of great interest for in vivo studies of GBFCs where the concentration of dissolved O(2) in the body tissues or biological fluids is very low compared to in vitro conditions (buffers under air). PMID:22906713

Ammam, Malika; Fransaer, Jan



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


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 H?O? 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. PMID:24384747

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



Attenuation of Experimental Colitis in Glutathione Peroxidase 1 and Catalase Double Knockout Mice through Enhancing Regulatory T Cell Function  

PubMed Central

Reactive oxygen species (ROS) have been implicated in the progression of inflammatory diseases including inflammatory bowel diseases (IBD). Meanwhile, several studies suggested the protective role of ROS in immune-mediated inflammatory diseases, and it was recently reported that dextran sodium sulfate (DSS)-induced colitis was attenuated in mice with an elevated level of ROS due to deficiency of peroxiredoxin II. Regulatory T cells (Tregs) are critical in the prevention of IBD and Treg function was reported to be closely associated with ROS level, but it has been investigated only in lowered levels of ROS so far. In the present study, in order to clarify the relationship between ROS level and Treg function, and their role in the pathogenesis of IBD, we investigated mice with an elevated level of ROS due to deficiency of both glutathione peroxidase (GPx)-1 and catalase (Cat) for the susceptibility of DSS-induced colitis in association with Treg function. The results showed that DSS-induced colitis was attenuated and Tregs were hyperfunctional in GPx1?/? × Cat?/? mice. In vivo administration of N-acetylcysteine (NAC) aggravated DSS-induced colitis and decreased Treg function to the level comparable to WT mice. Attenuated Th17 cell differentiation from naïve CD4+ cells as well as impaired production of IL-6 and IL-17A by splenocytes upon stimulation suggested anti-inflammatory tendency of GPx1?/? × Cat?/? mice. Suppression of Stat3 activation in association with enhancement of indoleamine 2,3-dioxygenase and FoxP3 expression might be involved in the immunosuppressive mechanism of GPx1?/? × Cat?/? mice. Taken together, it is implied that ROS level is critical in the regulation of Treg function, and IBD may be attenuated in appropriately elevated levels of ROS. PMID:24743300

Choi, Eun-Jeong; Kie, Jeong-Hae; Lim, Woosung; Lee, Hyeon Kook; Moon, Byung-In; Seoh, Ju-Young



Gluconic acid production in bioreactor with immobilized glucose oxidase plus catalase on polymer membrane adjacent to anion-exchange membrane.  


Gluconic acid was obtained in the permeate side of the bioreactor with glucose oxidase (GOD) immobilized onto anion-exchange membrane (AEM) of low-density polyethylene grafted with 4-vinylpiridine. The electric resistance of the anion-exchange membranes was increased after the enzyme immobilization on the membrane. The gluconic acid productions were relatively low with the GOD immobilized by any method on the AEM. To increase the enzyme reaction efficiency, GOD was immobilized on membrane of AN copolymer (PAN) adjacent to an anion-exchange membrane in bioreactor. Uses of anion-exchange membrane led to selective removal of the gluconic acid from the glucose solution and reduce the gluconic acid inhibition. The amount of gluconic acid obtained in the permeate side of the bioreactor with the GOD immobilized on the PAN membrane adjacent to the AEM under electrodialysis was about 30 times higher than that obtained with enzyme directly bound to the AEM. The optimal substrate concentration in the feed side was found to be about 1 g/l. Further experiments were carried out with the co-immobilized GOD plus Catalase (CAT) on the PAN membrane adjacent to the AEM to improve the efficiency of the immobilize system. The yield of this process was at least 95%. The storage stability of the co-immobilized GOD and CAT was studied (lost 20% of initial activity for 90 d). The results obtained clearly showed the higher potential of the dual membrane bioreactor with GOD plus CAT bound to ultrafiltration polymer membrane adjacent to the AEM. Storage stability of GOD activity in GOD plus CAT immobilized on PAN//AEM membranes and on AEM. PMID:15497133

Godjevargova, Tzonka; Dayal, Rajeshwar; Turmanova, Sevdalina



Detection of Human Intestinal Catalase-Negative, Gram-Positive Cocci by rRNA-Targeted Reverse Transcription-PCR? †  

PubMed Central

An analytical system based on rRNA-targeted reverse transcription-quantitative PCR (RT-qPCR) for enumeration of catalase-negative, Gram-positive cocci was established. Subgroup- or species-specific primer sets targeting 16S or 23S rRNA from Enterococcus, Streptococcus, and Lactococcus were newly developed. The RT-qPCR method using these primers together with the previously reported primer sets specific for the Enterococcus genus, the Streptococcus genus, and several Streptococcus species was found to be able to quantify the target populations with detection limits of 103 to 104 cells per gram feces, which was more than 100 times as sensitive as the qPCR method (106 to 108 cells per gram feces). The RT-qPCR analysis of fecal samples from 24 healthy adult volunteers using the genus-specific primer sets revealed that Enterococcus and Streptococcus were present as intestinal commensals at population levels of log10 6.2 ± 1.4 and 7.5 ± 0.9 per gram feces (mean ± standard deviation [SD]), respectively. Detailed investigation using species- or subgroup-specific primer sets revealed that the volunteers harbored unique Enterococcus species, including the E. avium subgroup, the E. faecium subgroup, E. faecalis, the E. casseliflavus subgroup, and E. caccae, while the dominant human intestinal Streptococcus species was found to be S. salivarius. Various Lactococcus species, such as L. lactis subsp. lactis or L. lactis subsp. cremoris, L. garvieae, L. piscium, and L. plantarum, were also detected but at a lower population level (log10 4.6 ± 1.2 per gram feces) and prevalence (33%). These results suggest that the RT-qPCR method enables the accurate and sensitive enumeration of human intestinal subdominant but still important populations, such as Gram-positive cocci. PMID:20581195

Kubota, Hiroyuki; Tsuji, Hirokazu; Matsuda, Kazunori; Kurakawa, Takashi; Asahara, Takashi; Nomoto, Koji



[Application of visible/near-infrared spectroscopy to the determination of catalase and peroxidase content in barley leaves].  


Visible/near-infrared spectroscopy was applied to determine the content of catalase (CAT) and peroxidase (POD) in barley leaves under the herbicide stress of propyl 4-(2-(4, 6-dimethoxypyrimidin-2-yloxy) benzylamino) benzoate (ZJ0273). The spectral data of the barley leaves in the range of 500-900 nm were preprocessed by moving average with 11 points. Seven outlier samples for CAT and 8 outlier samples for POD were detected and removed by Monte Carlo-partial least squares (MCPLS). PLS, least-squares support vector machine (LS-SVM) and extreme learning machine (ELM) models were built for both CAT and POD. ELM model obtained best results for CAT, with correlation coefficient of calibration (Rc) of 0.916 and correlation co-efficient of prediction (Rp) of 0.786. PLS model obtained best prediction results for POD, with Rc of 0.984 and Rp of 0.876. Successive projections algorithm (SPA) was applied to select 8 and 19 effective wavelengths for CAT and POD, respectively. PLS, LS-SVM and ELM models were built using the selected effective wavelengths of CAT and POD. ELM model performed best for CAT and POD prediction, with Rc of 0.928 and Rp of 0.790 for CAT and Rp of 0.965 and Rp of 0.941 for POD. The prediction results using the full spectral data and the effective wavelengths were quite close, and the prediction performance for POD was much better than the prediction performance for CAT, and the studies should be further explored to build more precise and more robust models for CAT and POD determination. The overall results indicated that it was feasible to use visible/near-infrared spectroscopy for CAT and POD content determination in barley leaves under the stress of ZJ0273. PMID:25532330

Zhao, Yun; Zhang, Chu; Liu, Fei; Kong, Wen-Wen; He, Yong



Effects of total dissolved gas supersaturated water on lethality and catalase activity of Chinese sucker (Myxocyprinus asiaticus Bleeker)*  

PubMed Central

Total dissolved gas (TDG) supersaturation caused by dam sluicing can result in gas bubble trauma (GBT) in fish and threaten their survival. In the present study, Chinese suckers (Myxocyprinus asiaticus Bleeker) were exposed to TDG supersaturated water at levels ranging from 120% to 145% for 48 h. The median lethal concentration (LC50) and the median lethal time (LT50) were determined to evaluate acute lethal effects on Chinese suckers. The results showed that the LC50 values of 4, 6, 8, and 10 h were 142%, 137%, 135%, and 130%, respectively. The LT50 values were 3.2, 4.7, 7.8, 9.2, and 43.4 h, respectively, when TDG supersaturated levels were 145%, 140%, 135%, 130%, and 125%. Furthermore, the biological responses in Chinese suckers were studied by assaying the catalase (CAT) activities in gills and muscles at the supersaturation level of 140% within LT50. The CAT activities in the gills and muscle tissues exhibited a regularity of a decrease after an increase. CAT activities in the muscles were increased significantly at 3/5LT50 (P<0.05) and then came back to the normal level. However, there were no significant differences between the treatment group (TDG level of 140%) and the control group (TDG level of 100%) on CAT activities in the gills before 3/5LT50 (P>0.05), but the activities were significantly lower than the normal level at 4/5LT50 and LT50 (P<0.05). PMID:23024046

Chen, Shi-chao; Liu, Xiao-qing; Jiang, Wen; Li, Ke-feng; Du, Jun; Shen, Dan-zhou; Gong, Quan



Effect of catalase and superoxide dismutase on motility, viability and acrosomal integrity of frozen-thawed cat spermatozoa.  


The aim of this study was to evaluate the effect of antioxidant catalase (CAT) and superoxide dismutase (SOD) in semen extender on motility, viability and acrosomal integrity of frozen-thawed cat spermatozoa. Semen was collected by using an artificial vagina from five domestic cats (two ejaculates/cat). Spermatozoa were diluted in egg yolk Ttris-fructose citrate solution (EYT-FC) without glycerol and cooled at 4 degrees C for 1 h, then diluted further with EYT-FC with glycerol (7% final concentration) and 400 IU/ml of CAT (treatment 1) or SOD (treatment 2) or without antioxidants (control). Before freezing using a styrofoam box, diluted spermatozoa filled in 0.25-ml straws were equilibrated for 1 h at 4 degrees C. After thawing, spermatozoa were assessed for motility, viability and acrosomal integrity. Cryopreservation significantly impaired sperm motility, viability and acrosomal integrity (p < 0.05). However, motility, viability and acrosomal integrity of frozen-thawed cat spermatozoa in the EYT-FC with CAT, SOD and without the antioxidants were not significantly different. The average percentages of spermatozoa motility after thawing compared between control, treatment 1 and treatment 2 group were 43.5 +/- 3.2, 42 +/- 4.1 and 38 +/- 4.5; for viability: 44.8 +/- 3.5, 50.6 +/- 5.7 and 47.1 +/- 4.1 and for acrosomal integrity: 45 +/- 3.5, 44.9 +/- 3.4 and 44.4 +/- 3.3, respectively. In conclusion, adding CAT and SOD to EYT-FC did not improve motility, viability and acrosomal integrity in cryopreserved cat spermatozoa. PMID:19754607

Thiangtum, K; Pinyopummin, A; Hori, T; Kawakami, E; Tsutsui, T



Enhanced reactive oxygen species scavenging by overproduction of superoxide dismutase and catalase delays postharvest physiological deterioration of cassava storage roots.  


Postharvest physiological deterioration (PPD) of cassava (Manihot esculenta) storage roots is the result of a rapid oxidative burst, which leads to discoloration of the vascular tissues due to the oxidation of phenolic compounds. In this study, coexpression of the reactive oxygen species (ROS)-scavenging enzymes copper/zinc superoxide dismutase (MeCu/ZnSOD) and catalase (MeCAT1) in transgenic cassava was used to explore the intrinsic relationship between ROS scavenging and PPD occurrence. Transgenic cassava plants integrated with the expression cassette p54::MeCu/ZnSOD-35S::MeCAT1 were confirmed by Southern-blot analysis. The expression of MeCu/ZnSOD and MeCAT1 was verified by quantitative reverse transcription-polymerase chain reaction and enzymatic activity analysis both in the leaves and storage roots. Under exposure to the ROS-generating reagent methyl viologen or to hydrogen peroxide (H2O2), the transgenic plants showed higher enzymatic activities of SOD and CAT than the wild-type plants. Levels of malondialdehyde, chlorophyll degradation, lipid peroxidation, and H2O2 accumulation were dramatically reduced in the transgenic lines compared with the wild type. After harvest, the storage roots of transgenic cassava lines show a delay in their PPD response of at least 10 d, accompanied by less mitochondrial oxidation and H2O2 accumulation, compared with those of the wild type. We hypothesize that this is due to the combined ectopic expression of Cu/ZnSOD and CAT leading to an improved synergistic ROS-scavenging capacity of the roots. Our study not only sheds light on the mechanism of the PPD process but also develops an effective approach for delaying the occurrence of PPD in cassava. PMID:23344905

Xu, Jia; Duan, Xiaoguang; Yang, Jun; Beeching, John R; Zhang, Peng



Improvement of superoxide dismutase and catalase in streptozotocin-nicotinamide-induced type 2-diabetes in mice by berberine and glibenclamide.  


Abstract Context: Diabetes mellitus (DM) type 2 is a chronic disease characterized by hyperglycemia and insulin resistance. Oxidative stress participates in development and progression of DM, in which changes of superoxide dismutase (SOD) and catalase (CAT) were noted in DM mice. Berberine has been widely used as an alternative medicine and proved to be effective for the treatment of DM and dyslipidemia. Objective: Impacts of berberine on transcriptional regulation of SOD and CAT and their enzyme activities, including the level of malondialdehyde (MDA) formation, were examined in the DM type 2-induced mice to clarify its antioxidation potential, compared with a common hypoglycemic drug, glibenclamide. Materials and methods: Noninsulin-dependent diabetes was induced in mice by a single intraperitoneal streptozotocin-nicotinamide injection. Diabetic mice were treated daily with glibenclamide (10?mg/kg/d) and/or berberine (100?mg/kg/d) for 2 weeks. The fasting blood glucose and the MDA levels in the mouse liver, brain and kidneys were monitored using Glucometer® (Accu-Check® Advantage II Performa kits, Roche Diagnostics, Germany) and thiobarbituric acid substance assay, respectively. The expression of SOD and CAT mRNA were determined in the mouse liver and the activities of SOD and CAT enzymes were determined in mouse liver, brain and kidneys, respectively. Results: Berberine exhibited similar hypoglycemic potential as glibenclamide to lower area under the curve of the fasting blood glucose. In DM type 2 mice, berberine increased the hepatic CuZn-SOD mRNA expression and the kidney SOD and CAT activities to normal levels. Moreover, DM-induced lipid peroxidation by increasing of MDA levels in both the liver and brain and lipid peroxidation status was restored by berberine. Conclusion: Berberine possessed hypoglycemic properties and strong potential to improve the oxidant-antioxidant balance, though the combination treatment of berberine and glibenclamide did not show additional benefit over the treatment with berberine alone. PMID:24188560

Chatuphonprasert, Waranya; Lao-Ong, Thinnakorn; Jarukamjorn, Kanokwan



alpha-Lipoic acid and glutathione protect against the prooxidant activity of SOD/catalase mimetic manganese salen derivatives.  


Manganese(III) N,N'-ethylenebis(salicylideneiminato) chloride (Mn-salen chloride) and manganese(III) N,N'-ethylenebis(3-methoxysalicylideneiminato) chloride (Mn-(3,3'-MeO)salen chloride) are in vitro superoxide dismutase and catalase mimetics. They protect against free radical-related disease in animals, but Mn-salen can also be a potent prooxidant, damaging free DNA. Mn-salen protects human fibroblast DNA against hydrogen peroxide damage, however, damage to free DNA was confirmed by the comet assay. The DNA-damaging activity was dramatically reduced by co-administration with glutathione with the combination being less damaging to free DNA than either molecule alone. alpha-Lipoic acid, an antioxidant disulfide commonly used as a dietary supplement, also prevented Mn-salen prooxidant activity. Mn-(3,3'-MeO)salen protected fibroblasts against hydrogen peroxide as efficiently as Mn-salen and showed little damaging activity against free DNA. Protection was invested by both complexes in the presence and in the absence of EDTA, a potential competing chelator. Stabilities of the complexes with respect to decomposition and inactivation were studied by spectroscopic and electrochemical techniques. The complexes' binding to, and cleavage of, DNA was measured using a quartz crystal resonant sensor. Mn-salen was shown to bind strongly to DNA, prior to cleaving it; Mn-(3,3'-MeO)salen bound weakly and left DNA intact. Co-administration of either glutathione or alpha-lipoic acid appears to inhibit binding by Mn-salen thus preventing DNA-cleavage. PMID:17095093

Fucassi, Flavia; Lowe, Jillian E; Pavey, Karl D; Shah, Seema; Faragher, Richard G A; Green, Michael H L; Paul, Frank; O'Hare, Danny; Cragg, Peter J



Simulated Microgravity Induces SOST/Sclerostin Upregulation in Osteocytes  

NASA Technical Reports Server (NTRS)

Osteocytes are theorized to be the mechanosensors and transducers of mechanical forces in bone, yet the biological mechanism of this action remains elusive. Recent evidence suggests that SOST/Sclerostin is an important regulator of mechano-transduction. To investigate the molecular mechanisms of SOST/Sclerostin regulation under in-vitro and ex-vivo unloading we used the NASA Rotating Wall Vessel(RWV) Bioreactor. For in-vitro experiments, MLOY-4 osteocytic cells were seeded at a concentration of 250,000 cells onto 3D collagen scaffold (BD). Scaffolds (4 per condition) were either rotated in a vertical 50ml NASA/bioreactor vessel at 18 rpm (unloaded), cultured in a horizontal 50 ml NASA bioreactor vessel at 18 rpm (control for the sheared environment of vertical rotating vessel), or cultured in a static T-75 cm dish (static condition ) for 7days. For ex-vivo experiments, calvaria bones were harvested from 12-week old C57/Bl6 mice and sequentially digested with type I/II collagenase to remove periosteal osteoblasts. Calvaria halves (10 per condition) were then exposed to the same set of culture conditions described above. Simulated unloading, as achieved in the NASA RWV, resulted in enlarged, round osteocytes, as assessed by H&E staining, that was reminiscent of prior reports of unloading causing loss of osteocyte morphology and dendritic network connectivity. Semiquantitative realtime qPCR and immunohistochemistry from both in-vitro and ex-vivo RWV experiments demonstrated a four-fold up-regulation of SOST/Sclerostin. Furthermore, mRNA of the transcriptional SOST enhancer Mef2C was upregulated 1.4 fold in ex-vivo calvaria subjected to unloading conditions of the NASA RWV, suggesting that Mef2C might be an important regulator of mechano-sensation. These findings are consistent with results from seven day hindlimb unloading experiments, C57/B6 females, conducted in our laboratory and validate the use of the NASA RWV as a tool to study osteocyte mechanotransduction

Spatz, Jordan; Sibonga, Jean; Wu, Honglu; Barry, Kevin; Bouxsein, Mary; Pajevic, Paola Divieti



Upregulation of FOXM1 induces genomic instability in human epidermal keratinocytes  

Microsoft Academic Search

BACKGROUND: The human cell cycle transcription factor FOXM1 is known to play a key role in regulating timely mitotic progression and accurate chromosomal segregation during cell division. Deregulation of FOXM1 has been linked to a majority of human cancers. We previously showed that FOXM1 was upregulated in basal cell carcinoma and recently reported that upregulation of FOXM1 precedes malignancy in

Muy-Teck Teh; Emilios Gemenetzidis; Tracy Chaplin; Bryan D Young; Michael P Philpott



Selective Th2 Upregulation by Crocus sativus: A Neutraceutical Spice  

PubMed Central

The immunomodulatory activity of an Indian neutraceutical spice, saffron (Crocus sativus) was studied on Th1 and Th2 limbs of the immune system. Oral administration of alcoholic extract of Crocus sativus (ACS) at graded dose levels from 1.56–50?mg/kg p.o. potentiated the Th2 response of humoral immunity causing the significant increases in agglutinating antibody titre in mice at a dose of 6.25?mg/kg and an elevation of CD19+ B cells and IL-4 cytokine, a signature cytokine of Th2 pathway. Appreciable elevation in levels of IgG-1 and IgM antibodies of the primary and secondary immune response was observed. However, ACS showed no appreciable expression of the Th1 cytokines IL-2 (growth factor for CD4+ T cells) and IFN-? (signature cytokine of Th1 response). A significant modulation of immune reactivity was observed in all the animal models used. This paper represents the selective upregulation of the Th2 response of the test material and suggests its use for subsequent selective Th2 immunomodulation. PMID:20953384

Bani, Sarang; Pandey, Anjali; Agnihotri, Vijai K.; Pathania, Vijaylata; Singh, Bikram



Involvement of NANOG upregulation in malignant progression of human cells.  


Previously, we isolated cell lines that display various degrees of transformed phenotypes from a single-cell population of human diploid fibroblasts (RB) containing a large deletion (13q14-22) in one copy of chromosome 13. They included a cell line transfected with SV40 early genes (RBSV), an immortalized cell line (RBI), an anchorage-independent cell line (RBS), and a tumorigenic cell line (RBT). Here, we analyzed gene expression profiles in these cell lines and showed that expression of some fibroblast-specified or mesenchyme-specified genes were downregulated, and those of stem cell-specified genes, including NANOG, were upregulated during malignant progression. When NANOG expression was knocked down with a short hairpin NANOG expression vector (shNANOG vector) in the RBS and RBT cells, the anchorage independency and tumorigenicity were repressed. We next examined various cancer cell lines for NANOG expression and showed that some cancer cell lines expressed a high level of normal and/or variant NANOG proteins. Overexpression of NANOG mRNA in lung adenocarcinoma was also shown by in situ hybridization. All these data indicate the involvement of NANOG in tumorigenesis. PMID:23427894

Li, Yang; Higashiyama, Shinji; Shimakage, Misuzu; Kawahara, Kunimitsu; Yutsudo, Masuo; Watari, Akihiro



Osteopontin Upregulates the Expression of Glucose Transporters in Osteosarcoma Cells  

PubMed Central

Osteosarcoma is the most common primary malignancy of bone. Even after the traditional standard surgical therapy, metastasis still occurs in a high percentage of patients. Glucose is an important source of metabolic energy for tumor proliferation and survival. Tumors usually overexpress glucose transporters, especially hypoxia-responsive glucose transporter 1 and glucose transporter 3. Osteopontin, hypoxia-responsive glucose transporter 1, and glucose transporter 3 are overexpressed in many types of tumors and have been linked to tumorigenesis and metastasis. In this study, we investigated the regulation of glucose transporters by osteopontin in osteosarcoma. We observed that both glucose transporters and osteopontin were upregulated in hypoxic human osteosarcoma cells. Endogenously released osteopontin regulated the expression of glucose transporter 1 and glucose transporter 3 in osteosarcoma and enhanced glucose uptake into cells via the ?v?3 integrin. Knockdown of osteopontin induced cell death in 20% of osteosarcoma cells. Phloretin, a glucose transporter inhibitor, also caused cell death by treatment alone. The phloretin-induced cell death was significantly enhanced in osteopontin knockdown osteosarcoma cells. Combination of a low dose of phloretin and chemotherapeutic drugs, such as daunomycin, 5-Fu, etoposide, and methotrexate, exhibited synergistic cytotoxic effects in three osteosarcoma cell lines. Inhibition of glucose transporters markedly potentiated the apoptotic sensitivity of chemotherapeutic drugs in osteosarcoma. These results indicate that the combination of a low dose of a glucose transporter inhibitor with cytotoxic drugs may be beneficial for treating osteosarcoma patients. PMID:25310823

Hsieh, I-Shan; Yang, Rong-Sen; Fu, Wen-Mei



Conditional Mutation of Pkd2 Causes Cystogenesis and Upregulates ?-Catenin  

PubMed Central

Loss of polycystin-2 (PC2) in mice (Pkd2?/?) results in total body edema, focal hemorrhage, structural cardiac defects, abnormal left-right axis, hepatorenal and pancreatic cysts, and embryonic lethality. The molecular mechanisms by which loss of PC2 leads to these phenotypes remain unknown. We generated a model to allow targeted Pkd2 inactivation using the Cre-loxP system. Global inactivation of Pkd2 produced a phenotype identical to Pkd2?/? mice with undetectable PC2 protein and perinatal lethality. Using various Cre mouse lines, we found that kidney, pancreas, or time-specific deletion of Pkd2 led to cyst formation. In addition, we developed an immortalized renal collecting duct cell line with inactive Pkd2; these cells had aberrant cell-cell contact, ciliogenesis, and tubulomorphogenesis. They also significantly upregulated ?-catenin, axin2, and cMyc. Our results suggest that loss of PC2 disrupts normal behavior of renal epithelial cells through dysregulation of ?-catenin-dependent signaling, revealing a potential role for this signaling pathway in PC2-associated ADPKD. PMID:19939939

Kim, Ingyu; Ding, Tianbing; Fu, Yulong; Li, Cunxi; Cui, Lan; Li, Ao; Lian, Peiwen; Liang, Dan; Wang, Dao W.; Guo, Caiying; Ma, Jie; Zhao, Ping; Coffey, Robert J.; Zhan, Qimin



RhoA Controls Wnt Upregulation on Microstructured Titanium Surfaces  

PubMed Central

Rough topography enhances the activation of Wnt canonical signaling in vitro, and this mediates its effects on cell differentiation. However, the molecular mechanisms underlying topography-dependent control of Wnt signaling are still poorly understood. As the small GTPase RhoA controls cytoskeletal reorganization and actomyosin-induced tensional forces, we hypothesized that RhoA could affect the activation of Wnt signaling in cells on micropatterned titanium surfaces. G-LISA assay revealed that RhoA activation was higher in C2C12 cells on rough (SLA) surfaces under basal conditions than on smooth (Polished) titanium. Transfection with dominant negative RhoA decreased Wnt activation by normalized TCF-Luc activity on SLA, whilst transfection with constitutively active RhoA increased TCF-Luc activation on Polished titanium. One mM Myosin II inhibitor Blebbistatin increased RhoA activation but decreased Wnt activation on SLA surfaces, indicating that tension-generating structures are required for canonical Wnt modulation on titanium surfaces. Actin inhibitor Cytochalasin markedly enhanced RhoA and TCF-Luc activation on both surfaces and increased the expression of differentiation markers in murine osteoblastic MC3T3 cells. Taken together, these data show that RhoA is upregulated in cells on rough surfaces and it affects the activation of Wnt canonical signaling through Myosin II modulation. PMID:24949442

Mazzotta, Silvia; Piergianni, Maddalena; Piemontese, Marilina; Passeri, Giovanni



The Catalase-Peroxidase KatG Is Required for Virulence of Xanthomonas campestris pv. campestris in a Host Plant by Providing Protection against Low Levels of H2O2?  

PubMed Central

Xanthomonas campestris pv. campestris katG encodes a catalase-peroxidase that has a role in protecting the bacterium against micromolar concentrations of H2O2. A knockout mutation in katG that causes loss of catalase-peroxidase activity correlates with increased susceptibility to H2O2 and a superoxide generator and is avirulent in a plant model system. katG expression is induced by oxidants in an OxyR-dependent manner. PMID:19783631

Jittawuttipoka, Thichakorn; Buranajitpakorn, Sarinya; Vattanaviboon, Paiboon; Mongkolsuk, Skorn



A discontinuous method for catalase determination at ‘near physiological’ concentrations of H 2O 2 and its application to the study of H 2O 2 fluxes within cells  

Microsoft Academic Search

We describe a discontinuous method for the measurement of catalase using the Ferrous Oxidation in Xylenol orange (FOX) assay. Samples containing catalase are incubated with H2O2 for varying time intervals prior to rapid mixing of aliquots of the incubation mixtures with FOX reagent, which measures residual H2O2. Absorbance is then read at 560 nm after 30-min incubation at room temperature.

Peimian Ou; Simon P. Wolff



Clonal spread of catalase-negative ST5/SCCmec II Staphylococcus aureus carrying the staphylococcal enterotoxin A (sea), staphylococcal enterotoxin b (seb), and toxic shock toxin (tst) virulence genes.  


17 catalase-negative methicillin-resistant Staphylococcus aureus (MRSA) isolates were recovered from respiratory specimens of patients at a 700-bed hospital in Korea. The goal of this study was to determine the molecular characteristics of catalase-negative MRSA strains in Korea for the first time. Characteristics that we explored included kat A gene mutation sequence, sequence type, staphylococcal cassette chromosome (SCC) mec subtype classification, and toxin gene profiles. All 17 isolates showed similar pulsed field gel electrophoresis (PFGE) pattern. Four mutations were identified in the kat A gene of a representative catalase-negative MRSA strain: A602G causing a histidine 201 to arginine change, A695T causing a glutamic acid 232 to valine change, T778A causing a tryptophan 260 to arginine change, and G1438A causing a glycine 480 to serine change. Previous studies suggest that the A695T and T778A mutations may have strong effects on the catalase activity of catalase-negative MRSA. The sequence type (ST) and SCCmec type of this isolate were ST 5 and SCCmec type II, respectively. All 17 isolates harbored toxic shock toxin (tst), staphylococcal enterotoxin A (sea), and staphylococcal enterotoxin B (seb) virulence genes. The mortality rate of the present study was 11.8%, suggesting that the clinical relevance of catalase-negative MRSA requires further study in the future. PMID:25361922

Lee, Hae Kyung; Kim, Jung-Beom; Kim, Hyunjung; Jekarl, Dong Wook; Kim, Yang Ree; Yu, Jin Kyung; Park, Yeon-Joon



Cystatin SN Upregulation in Patients with Seasonal Allergic Rhinitis  

PubMed Central

Seasonal allergic rhinitis (SAR) to the Japanese cedar, Cryptomeria japonica (JC) pollen is an IgE-mediated type I allergy affecting nasal mucosa. However, the molecular events underlying its development remain unclear. We sought to identify SAR-associated altered gene expression in nasal epithelial cells during natural exposure to JC pollen. We recruited study participants in 2009 and 2010 and collected nasal epithelial cells between February and April, which is the period of natural pollen dispersion. Fifteen patients with SAR-JC and 13 control subjects were enrolled in 2009, and 17 SAR-JC patients, 13 sensitized asymptomatic subjects (Sensitized), and 15 control subjects were enrolled in 2010. Total RNA was extracted from nasal epithelial cells and 8 SAR-JC patients and 6 control subjects in 2009 were subjected to microarray analysis with the Illumina HumanRef-8 Expression BeadChip platform. Allergen-stimulated histamine release was examined in the peripheral blood basophils isolated from patients with SAR. We identified 32 genes with significantly altered expression during allergen exposure. One of these, CST1 encodes the cysteine protease inhibitor, cystatin SN. CST1 expression in nasal epithelial cells was significantly upregulated in both the 2009 and 2010 SAR-JC groups compared with the control groups. Immunohistochemical staining confirmed the increased expression of CST1 in the nasal epithelial cells of SAR patients. Addition of exogenous CST1 to basophils inhibited JC allergen-stimulated histamine release in vitro. We propose that CST1 may contribute to inactivation of protease allergens and help re-establish homeostasis of the nasal membranes. PMID:23950865

Imoto, Yoshimasa; Tokunaga, Takahiro; Matsumoto, Yuri; Hamada, Yuko; Ono, Mizuho; Yamada, Takechiyo; Ito, Yumi; Arinami, Tadao; Okano, Mitsuhiro; Noguchi, Emiko; Fujieda, Shigeharu



Upregulation of cognitive control networks in older adults' speech comprehension.  


Speech comprehension abilities decline with age and with age-related hearing loss, but it is unclear how this decline expresses in terms of central neural mechanisms. The current study examined neural speech processing in a group of older adults (aged 56-77, n = 16, with varying degrees of sensorineural hearing loss), and compared them to a cohort of young adults (aged 22-31, n = 30, self-reported normal hearing). In a functional MRI experiment, listeners heard and repeated back degraded sentences (4-band vocoded, where the temporal envelope of the acoustic signal is preserved, while the spectral information is substantially degraded). Behaviorally, older adults adapted to degraded speech at the same rate as young listeners, although their overall comprehension of degraded speech was lower. Neurally, both older and young adults relied on the left anterior insula for degraded more than clear speech perception. However, anterior insula engagement in older adults was dependent on hearing acuity. Young adults additionally employed the anterior cingulate cortex (ACC). Interestingly, this age group × degradation interaction was driven by a reduced dynamic range in older adults who displayed elevated levels of ACC activity for both degraded and clear speech, consistent with a persistent upregulation in cognitive control irrespective of task difficulty. For correct speech comprehension, older adults relied on the middle frontal gyrus in addition to a core speech comprehension network recruited by younger adults suggestive of a compensatory mechanism. Taken together, the results indicate that older adults increasingly recruit cognitive control networks, even under optimal listening conditions, at the expense of these systems' dynamic range. PMID:24399939

Erb, Julia; Obleser, Jonas



Cloning, expression and characterization of the catalase-peroxidase (KatG) gene from a fast-growing Mycobacterium sp. strain JC1 DSM 3803.  


The gene encoding a catalase-peroxidase (KatG) was cloned from chromosomal DNA of a fast-growing Mycobacterium sp. strain JC1 DSM 3803. The nucleotide sequence of a 5.7 kb EcoRI fragment containing the katG and its flanking regions was determined. The fragment (5,706 bps) contained two complete open reading frames (ORFs) encoding putative ferric uptake regulator A (FurA) and KatG proteins. The cloned gene, katG, had an ORF of 2241 nt, encoding a protein with calculated molecular mass of 81,748 Da. The furA was located in the upstream of the katG with the same transcriptional direction and there was a 38 bp gap space between them. The deduced KatG and FurA protein sequences showed significant homologies to KatG2 and Fur2 of Mycobacterium smegmatis and clustered with other mycobacterial KatG and Fur-like proteins in phylogenetic trees, respectively. The recombinant KatG overproduced in Escherichia coli was nearly indistinguishable from the native JC1 catalase-peroxidase in enzymatic properties and also possessed the resistance to organic solvents, indicating that the cloned katG truly encodes the Mycobacterium sp. JC1 catalase-peroxidase. Difference spectroscopy revealed Mn(II) binding near the haem of the KatG. Transcript analysis of the furA-katG using RT-PCR suggests that the katG is independently transcribed from the furA. PMID:19933836

Lee, Hyun-Il; Yoon, Ji-Hyun; Nam, Ji-Sun; Kim, Young-Min; Ro, Young-Tae



Immobilization of catalase on electrospun PVA/PA6-Cu(II) nanofibrous membrane for the development of efficient and reusable enzyme membrane reactor.  


In this study, a mat/membrane consisting of overlaid PVA/PA6-Cu(II) composite nanofibers was prepared via the electrospinning technique followed by coordination/chelation with Cu(II) ions; an enzyme of catalase (CAT) was then immobilized onto the PVA/PA6-Cu(II) nanofibrous membrane. The amount of immobilized catalase reached a high value of 64 ± 4.6 mg/g, while the kinetic parameters (Vmax and Km) of enzyme were 3774 ?mol/mg·min and 41.13 mM, respectively. Furthermore, the thermal stability and storage stability of immobilized catalase were improved significantly. Thereafter, a plug-flow type of immobilized enzyme membrane reactor (IEMR) was assembled from the PVA/PA6-Cu(II)-CAT membrane. With the increase of operational pressure from 0.02 to 0.2 MPa, the flux value of IEMR increased from 0.20 ± 0.02 to 0.76 ± 0.04 L/m(2)·min, whereas the conversion ratio of H2O2 decreased slightly from 92 ± 2.5% to 87 ± 2.1%. After 5 repeating cycles, the production capacity of IEMR was merely decreased from 0.144 ± 0.006 to 0.102 ± 0.004 mol/m(2)·min. These results indicated that the assembled IEMR possessed high productivity and excellent reusability, suggesting that the IEMR based on electrospun PVA/PA6-Cu(II) nanofibrous membrane might have great potential for various applications, particularly those related to environmental protection. PMID:25093534

Feng, Quan; Zhao, Yong; Wei, Anfang; Li, Changlong; Wei, Qufu; Fong, Hao



Tissue-specific methylation of individual CpG dinucleotides in the 5{prime} upstream region of the mouse catalase gene (Cas-1)  

SciTech Connect

The intracellular antioxidant enzyme, catalase, is encoded by a gene whose level of expression in different organisms, including humans, varies with tissue-type. The {open_quotes}TATA-less{close_quotes} 5{prime} upstream region of the catalase gene, in mice and humans, contains a CpG island. Such CG-rich regions are target sites for cytosine methylation and have been implicated in tissue-specific gene expression. However, the methylation status of individual CpG dinucleotides and their significance in gene expression has not been established. A 275 bp fragment within the 5{prime} region of Cas-1 was evaluated for CpG methylation. HpaII digestion of genomic DNA, followed by polymerase chain reaction amplification (HpaII-PCR), suggests that at least one of three CCGG is not methylated in nine different somatic tissues that express this enzyme at various levels. In contrast, all three CCGG sites are methylated in DNA from sperm and spleen. Further examination of the methylation specificity of individual CCGG sites was conducted using sodium bisulfite modification of genomic DNA followed by HPaII-PCR. Sodium bisulfite modifies non-methylated cytosines to uracils, changing a CG to a TG dinucleotide. This nucleotide substitution eliminates HpaII sites and allows the methylation status of each of the CCGG sites to be assessed. The ability to discern the number and combination of methylated sites within the 5{prime} region of a gene permits the determination of a possible correlation between differential methylation patterns and temporal/spatial gene regulation. Analysis of differential methylation, using the mouse catalase gene as a model, provides further insight into CpG methylation as one mechanism of mammalian gene regulation.

Pillay, I.L.; Singh, S.M. [Univ. of Western Ontario (Canada)



Transcriptional Regulation of the CmeABC Multidrug Efflux Pump and the KatA Catalase by CosR in Campylobacter jejuni  

PubMed Central

CosR is an essential response regulator in Campylobacter jejuni, a major food-borne pathogen causing enteritis worldwide. A transcriptomic analysis performed in this study discovered 93 genes whose transcriptional levels were changed >2-fold due to the repression of CosR expression by antisense peptide nucleic acid. The identified CosR-regulated genes are involved in various cellular functions, such as energy production, protein synthesis and folding, flagellum biogenesis, and lipid metabolism. Interestingly, 17 of the 93 CosR-regulated genes (18.3%) are predicted essential genes, indicating that CosR may participate in the regulation of vital biological processes in C. jejuni. In particular, CosR knockdown increased the transcriptional levels of cmeA, cmeB, and cmeC genes, whose protein product (CmeABC) is an important determinant conferring multidrug resistance in Campylobacter. Negative regulation of cmeABC by CosR was verified by quantitative real-time PCR (qRT-PCR) and PcmeABC::lacZ assay. The results of electrophoretic mobility shift assays (EMSAs) and DNase I footprinting assays demonstrated that CosR directly binds to the cmeABC promoter. Another notable finding is that CosR regulates the transcription of katA, the sole catalase gene in C. jejuni. Further characterization with qRT-PCR, the catalase enzyme assay, EMSA, and DNase I footprinting assays successfully demonstrated that CosR affects the katA transcription and the catalase activity by direct interactions with the katA promoter. The findings in this study clearly demonstrated that CosR regulates resistance mechanisms in C. jejuni by controlling the expression of genes involved in oxidative stress defense and extrusion of toxic compounds out of the cell. PMID:23065977

Hwang, Sunyoung; Zhang, Qijing; Ryu, Sangryeol



Transcriptome changes in foxtail millet genotypes at high salinity: identification and characterization of a PHGPX gene specifically upregulated by NaCl in a salt-tolerant line.  


Using a macro array filter with 711 cDNA inserts representing 620 unigenes selected from a barley EST collection, we identified transcripts differentially expressed in salt (NaCl)-treated tolerant (cv. Prasad) and sensitive (cv. Lepakshi) seedlings of foxtail millet (Setaria italica L.). Transcripts of hydrogen peroxide scavenging enzymes such as phospholipid hydroperoxide glutathione peroxidase (PHGPX), ascorbate peroxidase (APX) and catalase 1 (CAT1) in addition to some genes of cellular metabolism were found to be especially up-regulated at high salinity in the tolerant line. To analyse this process at the protein level we examined protein expression patterns under various stress conditions. A 25 kD protein with a pI of 4.8 was found to be induced prominently under high salt concentrations (250 mmol/L). This salt-induced 25 kD protein has been purified and identified by peptide sequencing as PHGPX protein. The increase of the PHGPX protein level under salt stress in the tolerant line parallels the PHGPX mRNA results of array analysis but was more pronounced. We cloned and characterized the foxtail millet PHGPX cDNA, which shows 85% and 95% homology at the DNA and protein level, respectively, to one stress-induced member of the small barley PHGPX gene family encoding non-selenium glutathione peroxidases. As shown by Southern blot analysis, a small family of PHGPX genes exists in foxtail millet, too. The specific expression pattern of the PHGPX gene in salt-induced tolerant millet seedlings suggests that its product plays an important role in the defense reaction against salt-induced oxidative damage and that the characterized glutathione peroxidase is one of the components conferring resistance against salt to the tolerant foxtail millet cultivar. PMID:15128034

Sreenivasulu, Nese; Miranda, Manoela; Prakash, Harischandra Sripathy; Wobus, Ulrich; Weschke, Winfriede



Catalase adsorption onto Cibacron Blue F3GA and Fe(III)-derivatized poly(hydroxyethyl methacrylate) membranes and application to a continuous system  

Microsoft Academic Search

Poly(2-hydroxyethyl methacrylate) (poly(HEMA)) membranes were prepared by UV-initiated photopolymerization of HEMA in the presence of an initiator (a-a?-azobisisobutyronitrile, AIBN). An affinity dye, i.e. Cibacron Blue F3GA (CB) was incorporated covalently and then complexed with Fe(III) ions. The polyHEMA-CB and polyHEMA-CB-Fe(III) derivatized membranes were used in the adsorption of catalase (CAT). The enzyme-loading capability of the Fe(III)-containing membrane (23.6 ?g\\/cm2) was

M. Yakup Arica; Adil Denizli; Bekir Salih; Erhan Piskin; Vasif Hasirci



Detection and monitoring of localized matrix metalloproteinase upregulation in a murine model of asthma  

E-print Network

Detection and monitoring of localized matrix metalloproteinase upregulation in a murine model RY. Detection and monitoring of localized matrix metalloproteinase upregula- tion in a murine model.1152/ajplung.00371.2013.--Extracellular proteases includ- ing matrix metalloproteinases (MMPs) are speculated

Tsien, Roger Y.


Nicotine-induced upregulation of native neuronal nicotinic receptors is caused by multiple mechanisms  

PubMed Central

Nicotine causes changes in brain nicotinic acetylcholine receptors (nAChRs) during smoking that initiate addiction. Nicotine-induced upregulation is the long-lasting increase in nAChR radio-ligand binding sites in brain resulting from exposure. The mechanisms causing upregulation are not established. Many different mechanisms have been reported with the assumption that there is a single, underlying cause. Using live cortical neurons, we examined for the first time how exposure and withdrawal of nicotine shape the kinetics of native ?4?2-containing nAChR upregulation in real time. Upregulation kinetics demonstrate that at least two different mechanisms underlie this phenomenon. First, a transient upregulation occurs that rapidly reverses, faster than nAChR degradation, and corresponds to nAChR conformational changes as assayed by conformational-dependent, subunit-specific antibodies. Second, a long-lasting process occurs correlating with increases in nAChR numbers caused by decreased proteasomal subunit degradation. Previous radio-ligand binding measurements to brain tissue have measured the second process and largely missed the first. We conclude that nicotine-induced upregulation is composed of multiple processes occurring at different rates with different underlying causes. PMID:22323734

Govind, Anitha P.; Walsh, Heather; Green, William N.



Up-regulation of ECT2 is associated with poor prognosisn gastric cancer patients  

PubMed Central

Objectives: The aim of this study was to investigate the expression of ECT2 in gastric cancer and its clinical significance. Methods and results: We investigated the differentially expressed genes between gastric cancer tissues and normal gastric mucosa by cDNA microarray, and then we found ECT2 was up-regulated in gastric cancer. What is more, we verified ECT2 expression level by quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR) and measured its protein level by immunohistochemistry (IHC). qRT-PCR analysis indicated ECT2 was significantly up-regulated in gastric cancer and Immunohistochemistry confirmed the percentage of ECT2-positive specimens was significantly higher in gastric carcinoma than in non-tumor tissues. Up-regulation of ECT2 is associated with the degree of histological differentiation (P = 0.007), invasion depth (P = 0.047), lymph node metastasis (P = 0.016), distant metastasis (P = 0.021) and TNM stage (P = 0.016), patients with up-regulated ECT2 had a lower overall survival rate (P = 0.000). Cox regression analysis revealed that up-regulation of ECT2 is an independent prognostic factor in gastric cancer patients (P = 0.012). Conclusion: Up-regulation of ECT2 might contribute to the progression of gastric carcinogenesis and may be a useful prognostic indicator in gastric cancer.

Jin, Yi; Yu, Yuhui; Shao, Qinshu; Ma, Yingyu; Zhang, Ruxuan; Yao, Haibo; Xu, Yuan



The involvement of nuclear factor-?appaB in the nuclear targeting and cyclin E1 upregulating activities of hepatoma upregulated protein.  


Hepatoma upregulated protein (HURP) is originally isolated during the search for the genes associated with hepatoma. HURP is upregulated in many human cancers. Culture cells exhibit transformed and invasive phenotype when ectopic HURP is introduced, revealing HURP as an oncogene candidate. Our previous studies demonstrated that Aurora-A regulated the cell transforming activities of HURP by phosphorylating HURP at four serines. To unravel how the Aurora-A/HURP cascade contributes to cell transformation, we firstly noticed that HURP shuttled between cytoplasm and nucleus. The nuclear localization activity of HURP was promoted or abolished by overexpression or knockdown of Aurora-A. Similarly, the HURP phosphorylation mimicking mutant 4E had higher nuclear targeting activity than the phosphorylation deficient mutant 4A. The HURP 4E accelerated G1 progression and upregulated cyclin E1, and the cyclin E1 upregulating and cell transforming activities of HURP were diminished when the nuclear localization signal (NLS) was removed from HURP. Furthermore, HURP employed p38/nuclear factor-?B (NF-?B) cascade to stimulate cell growth. Interestingly, NF-?B trapped HURP in nucleus by interacting with HURP 4E. At last, the HURP/NF-?B complex activated the cyclin E1 promoter. Collectively, Aurora-A/HURP relays cell transforming signal to NF-?B, and the HURP/NF-?B complex is engaged in the regulation of cyclin E1 expression. PMID:25289861

Chen, Jo-Mei Maureen; Chiu, Shao-Chih; Wei, Tong-You Wade; Lin, Shin-Yi; Chong, Cheong-Meng; Wu, Chi-Chen; Huang, Jiao-Ying; Yang, Shu-Ting; Ku, Chia-Feng; Hsia, Jiun-Yi; Yu, Chang-Tze Ricky



Increased Antigen Presentation but Impaired T Cells Priming after Upregulation of Interferon-Beta Induced by Lipopolysaccharides Is Mediated by Upregulation of B7H1 and GITRL  

PubMed Central

Dendritic cells are able to present Ag-derived peptides on MHC class I and II molecules and induce T cells priming. Lipopolysaccharides (LPS), an activator of Toll-like 4 receptor (TLR4) signaling, has been demonstrated to facilitate Ag-presentation, up-regulate surface molecules expression but impair T cells priming. In this study, we investigated the effect of LPS on nicotine-enhanced DCs-dependent T cells priming and the mechanisms of LPS orchestrating the immunosuppressive program. We could demonstrate that the treatment with LPS resulted in increased surface molecules expression, enhanced Ag-presentation, up-regulated release of TGF-beta, TNF-alpha, IL-6, and IFN-beta. Concomititantly, the upregulation of IFN-beta in DCs induces the up-regulation of coinhibitory molecules B7H1 and GITRL, which cause an impaired activation of naïve Ag-specific T cells and the induction of T cell tolerance by enhancing B7H1-PD-1 interactions and promoting GITRL-GITL facilitated Treg generation, respectively. These data provide a mechanistic basis for the immunomodulatory action of IFN-beta which might open new possibilities in the development of therapeutic approaches aimed at the control of excessive immune response and persistent infection. PMID:25144375

Li, Juan; You, Xiang; Qiu, Xin Hui; Wang, Yi Nan; Gao, Feng Guang



Peroxiredoxin-Glutaredoxin and Catalase Promote Resistance of Nontypeable Haemophilus influenzae 86-028NP to Oxidants and Survival within Neutrophil Extracellular Traps.  


Nontypeable Haemophilus influenzae (NTHI) is a common commensal and opportunistic pathogen of the human airways. For example, NTHI is a leading cause of otitis media and is the most common cause of airway infections associated with chronic obstructive pulmonary disease (COPD). These infections are often chronic/recurrent in nature and involve bacterial persistence within biofilm communities that are highly resistant to host clearance. Our previous work has shown that NTHI within biofilms has increased expression of factors associated with oxidative stress responses. The goal of this study was to define the roles of catalase (encoded by hktE) and a bifunctional peroxiredoxin-glutaredoxin (encoded by pdgX) in resistance of NTHI to oxidants and persistence in vivo. Isogenic NTHI strain 86-028NP mutants lacking hktE and pdgX had increased susceptibility to peroxide. Moreover, these strains had persistence defects in the chinchilla infection model for otitis media, as well as in a murine model for COPD. Additional work showed that pdgX and hktE were important determinants of NTHI survival within neutrophil extracellular traps (NETs), which we have shown to be an integral part of NTHI biofilms in vivo. Based on these data, we conclude that catalase and peroxiredoxin-glutaredoxin are determinants of bacterial persistence during chronic/recurrent NTHI infections that promote bacterial survival within NETs. PMID:25348637

Juneau, Richard A; Pang, Bing; Armbruster, Chelsie E; Murrah, Kyle A; Perez, Antonia C; Swords, W Edward



Degradation of direct yellow 9 by electro-Fenton: Process study and optimization and, monitoring of treated water toxicity using catalase.  


The present study was undertaken to investigate the degradation and removal of direct yellow 9 (DY9) by the electro-Fenton (EF) process in batch reactor using iron and stainless steel electrodes. DY9 removal decreased with the increase in pH (3 to 8) and increased with the increase in current intensity (0.05 to 0.2A) and [H2O2] (0 to 0.5gL(-1), but not with high doses which led to low rates of DY9 removal and OH(?) uptake). The regression quadratic models describing DY9 degradation yield "R (percent)" and electrical energy consumption "EEC (kWhkg(-1))" were validated by the analysis of variance (ANOVA) and were both noted to fit well with the experimental data. The R(2) correlation coefficients (0.995, 0.978), those adjusted coefficients (0.986, 0.939), and F values (110.7, 24.9) obtained for the responses validated the efficiency of model. The results revealed that among several other parameters, EEC depended essentially on the degradation yield. The eco-toxicity tests showed a positive correlation between catalase activity and DY9 concentration, and catalase could be qualitatively identified to assess the effect of dye and its by-products generated during the EF process. PMID:25216029

Kourdali, Sidali; Badis, Abdelmalek; Boucherit, Ahmed



Expression of a highly active catalase VktA in the cyanobacterium Synechococcus elongatus PCC 7942 alleviates the photoinhibition of photosystem II.  


The repair of photosystem II (PSII) after photodamage is particularly sensitive to reactive oxygen species-such as H2O2, which is abundantly produced during the photoinhibition of PSII. In the present study, we generated a transformant of the cyanobacterium Synechococcus elongatus PCC 7942 that expressed a highly active catalase, VktA, which is derived from a facultatively psychrophilic bacterium Vibrio rumoiensis, and examined the effect of expression of VktA on the photoinhibition of PSII. The activity of PSII in transformed cells declined much more slowly than in wild-type cells when cells were exposed to strong light in the presence of H2O2. However, the rate of photodamage to PSII, as monitored in the presence of chloramphenicol, was the same in the two lines of cells, suggesting that the repair of PSII was protected by the expression of VktA. The de novo synthesis of the D1 protein, which is required for the repair of PSII, was activated in transformed cells under the same stress conditions. Similar protection of the repair of PSII in transformed cells was also observed under strong light at a relatively low temperature. Thus, the expression of the highly active catalase mitigates photoinhibition of PSII by protecting protein synthesis against damage by H2O2 with subsequent enhancement of the repair of PSII. PMID:23456267

Jimbo, Haruhiko; Noda, Akiko; Hayashi, Hidenori; Nagano, Takanori; Yumoto, Isao; Orikasa, Yoshitake; Okuyama, Hidetoshi; Nishiyama, Yoshitaka



Granulocyte Colony Stimulating Factor Induces Lipopolysaccharide (LPS) Sensitization via Upregulation of LPS Binding Protein in Rat  

PubMed Central

Liver is the main organ for lipopolysaccharide (LPS) clearance. Sensitization to LPS is associated with the upregulation of LPS-binding protein (LBP) in animal models. Therefore, we hypothesized that LBP could induce LPS sensitization through enhancing hepatic uptake of LPS. In this study, we examined the role of LBP in pathogenesis of LPS induced systemic inflammatory response syndrome (SIRS). LBP expression was upregulated after granulocyte colony stimulating (G-CSF) pretreatment. The effect of LBP was further confirmed by blockade of LBP using LBP blocking peptide – LBPK95A. After G-CSF pretreatment, upregulation of LBP was observed in bone marrow cells and liver. The G-CSF induced LBP upregulation caused LPS hypersensitization in rats as indicated by higher mortality and severer liver damage. Of note, LBP blockade increased the survival rate and attenuated the liver injury. The LBP induced LPS hypersensitization was associated with increased hepatic uptake of LPS and augmented hepatic expression of LPS receptors, such as toll-like receptor (TLR)-4. Furthermore, LBP mediated early neutrophil infiltration, which led to increased monocyte recruitment in liver after LPS administration. In conclusion, G-CSF induced LBP expression could serve as a new model for investigation of LPS sensitization. We demonstrated the crucial role of LBP upregulation in pathogenesis of LPS induced SIRS. PMID:23437199

Fang, Haoshu; Liu, Anding; Sun, Jian; Kitz, Alexandra; Dirsch, Olaf; Dahmen, Uta



Crystal structure of the catalase-peroxidase KatG W78F mutant from Synechococcus elongatus PCC7942 in complex with the antitubercular pro-drug isoniazid.  


Isoniazid (INH) is a pro-drug that has been extensively used to treat tuberculosis. INH is activated by the heme enzyme catalase-peroxidase (KatG), but the mechanism of the activation is poorly understood, in part because the INH binding site has not been clearly established. Here, we observed that a single-residue mutation of KatG from Synechococcus elongatus PCC7942 (SeKatG), W78F, enhances INH activation. The crystal structure of INH-bound KatG-W78F revealed that INH binds to the heme pocket. The results of a thermal-shift assay implied that the flexibility of the SeKatG molecule is increased by the W78F mutation, allowing the INH molecule to easily invade the heme pocket through the access channel on the ?-edge side of the heme. PMID:25479089

Kamachi, Saori; Hirabayashi, Kei; Tamoi, Masahiro; Shigeoka, Shigeru; Tada, Toshiji; Wada, Kei



Basic fibroblast growth factor induces miR-134 upregulation in astrocyte for cell maturation.  


Evidence suggests that neuronal microRNAs (miRs) contribute to synaptic plasticity, although a role of glial miRs have been unknown. Growth factors including brain-derived neurotrophic factor (BDNF) regulate neuronal functions via upregulation of miRs, while possible influences on expression/function of glial miRs have not been fully understood. Here, we report that basic fibroblast growth factor (bFGF) increased miR-134 expression in astrocyte. The miR-134 was upregulated through stimulating extracellular signal-regulated kinase and phosphatidylinositol 3-kinase signaling, because inhibitors for each signaling blocked the miR-134 induction by bFGF. We also found upregulation of glial fibrillary acidic protein (astrocyte marker) and decreased extracellular concentration of glutamate after miR-134 overexpression and bFGF application, suggesting that astroglial cell maturation is enhanced by bFGF through induction of miR-134. PMID:25482448

Numakawa, Tadahiro; Nakajima, Shingo; Yamamoto, Noriko; Ooshima, Yoshiko; Odaka, Haruki; Hashido, Kazuo; Adachi, Naoki; Kunugi, Hiroshi



Infective Endocarditis: Identification of Catalase-Negative, Gram-Positive Cocci from Blood Cultures by Partial 16S rRNA Gene Analysis and by Vitek 2 Examination  

PubMed Central

Streptococci, enterococci and Streptococcus-like bacteria are frequent etiologic agents of infective endocarditis and correct species identification can be a laboratory challenge. Viridans streptococci (VS) not seldomly cause contamination of blood cultures. Vitek 2 and partial sequencing of the 16S rRNA gene were applied in order to compare the results of both methods. Strains originated from two groups of patients: 149 strains from patients with infective endocarditis and 181 strains assessed as blood culture contaminants. Of the 330 strains, based on partial 16S rRNA gene sequencing results, 251 (76%) were VS strains, 10 (3%) were pyogenic streptococcal strains, 54 (16%) were E. faecalis strains and 15 (5%) strains belonged to a group of miscellaneous catalase-negative, Gram-positive cocci. Among VS strains, respectively, 220 (87,6%) and 31 (12,3%) obtained agreeing and non-agreeing identifications with the two methods with respect to allocation to the same VS group. Non-agreeing species identification mostly occurred among strains in the contaminant group, while for endocarditis strains notably fewer disagreeing results were observed. Only 67 of 150 strains in the mitis group strains obtained identical species identifications by the two methods. Most VS strains belonging to the groups of salivarius, anginosus, and mutans obtained agreeing species identifications with the two methods, while this only was the case for 13 of the 21 bovis strains. Pyogenic strains (n=10), Enterococcus faecalis strains (n=54) and a miscellaneous group of catalase-negative, Gram-positive cocci (n=15) seemed well identified by both methods, except that disagreements in identifications in the miscellaneous group of strains occurred for 6 of 15 strains. PMID:21673976

Abdul-Redha, Rawaa Jalil; Kemp, Michael; Bangsborg, Jette M; Arpi, Magnus; Christensen, Jens Jørgen



RIP1 potentiates BPDE-induced transformation in human bronchial epithelial cells through catalase-mediated suppression of excessive reactive oxygen species  

PubMed Central

Cell survival signaling is important for the malignant phenotypes of cancer cells. Although the role of receptor-interacting protein 1 (RIP1) in cell survival signaling is well documented, whether RIP1 is directly involved in cancer development has never been studied. In this report, we found that RIP1 expression is substantially increased in human non-small cell lung cancer and mouse lung tumor tissues. RIP1 expression was remarkably increased in cigarette smoke-exposed mouse lung. In human bronchial epithelial cells (HBECs), RIP1 was significantly induced by cigarette smoke extract or benzo[a]pyrene diol epoxide (BPDE), the active form of the tobacco-specific carcinogen benzo(a)pyrene. In RIP1 knockdown HBECs, BPDE-induced cytotoxicity was significantly increased, which was associated with induction of cellular reactive oxygen species (ROS) and activation of mitogen-activated protein kinases (MAPKs), including c-jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK) and p38. Scavenging ROS suppressed BPDE-induced MAPK activation and inhibiting ROS or MAPKs substantially blocked BPDE-induced cytotoxicity, suggesting ROS-mediated MAPK activation is involved in BPDE-induced cell death. The ROS-reducing enzyme catalase is destabilized in an ERK- and JNK-dependent manner in RIP1 knockdown HBECs and application of catalase effectively blocked BPDE-induced ROS accumulation and cytotoxicity. Importantly, BPDE-induced transformation of HBECs was significantly reduced when RIP1 expression was suppressed. Altogether, these results strongly suggest an oncogenic role for RIP1, which promotes malignant transformation through protecting DNA-damaged cells against carcinogen-induced cytotoxicity associated with excessive ROS production. PMID:23633517

Lin, Yong



Superoxide dismutase, catalase, and glutathione peroxidase in the testis of the Mexican big-eared bat (Corynorhinus mexicanus) during its annual reproductive cycle.  


The reproductive physiology of Corynorhinus mexicanus includes a testes growth-involution cycle. Testis recrudescence begins in May-June, peaks in August and then undergoes a profound involution being totally regressed in November. Adult, male individuals were captured monthly during one year and ROS scavenging enzyme activities were measured in testes and expressed per total wet-weight and per mg protein. SOD total activity is very low from October to February; increases sharply one full month before testes recrudescence starts, and in August, when testis activity was at its peak, SOD is 3-4 times lower than in July. Catalase total activity is bimodal. The main peak of activity occurs during testicular recrudescence with an additional smaller peak, two months before the onset of recrudescence. Glutathione peroxidase total activity parallels almost exactly the testis growth cycle, increases in July, reaches a peak in August and decreases through September to almost disappear in October. SOD specific activity shows a pre-testicular increase of activity, maintains its activity from March to July and then descends drastically to almost nil in August, maintaining these low values until February. Catalase specific activity is particularly important during the period of testicular regression. GPX specific activity is low from March to July, months of testicular recrudescence; whereas its activity increases in August and peaks in November, when testes regression occurs. Our data show that ROS-scavenging enzymes may play a very important role during testes involution-recrudescence in C. mexicanus, and we believe their participation could be equally important in all seasonally breeding mammals. PMID:17481934

Arenas-Ríos, E; León-Galván, M A; Mercado, P E; López-Wilchis, R; Cervantes, D L M I; Rosado, A



Oxidation of nitric oxide by oxomanganese-salen complexes: a new mechanism for cellular protection by superoxide dismutase/catalase mimetics.  

PubMed Central

Manganese-salen complexes (Mn-Salen), including EUK-8 [manganese N,N'-bis(salicylidene)ethylenediamine chloride] and EUK-134 [manganese 3-methoxy N,N'-bis(salicylidene)ethylenediamine chloride], have been reported to possess combined superoxide dismutase (SOD) and catalase mimetic functions. Because of this SOD/catalase mimicry, EUK-8 and EUK-134 have been investigated as possible therapeutic agents in neurological disorders resulting from oxidative stress, including Alzheimer's disease, Parkinson's disease, stroke and multiple sclerosis. These actions have been explained by the ability of the Mn-Salen to remove deleterious superoxide (O(2)(-)) and H(2)O(2). However, in addition to oxidative stress, cells in models for neurodegenerative diseases may also be subjected to damage from reactive nitrogen oxides (nitrosative stress), resulting from elevated levels of NO and sister compounds, including peroxynitrite (ONOO(-)). We have been examining the interaction of EUK-8 and EUK-134 with NO and ONOO(-). We find that in the presence of a per-species (H(2)O(2), ONOO(-), peracetate and persulphate), the Mn-Salen complexes are oxidized to the corresponding oxo-species (oxoMn-Salen). OxoMn-Salens are potent oxidants, and we demonstrate that they can rapidly oxidize NO to NO(2) and also oxidize nitrite (NO(2)(-) to nitrate (NO(2)(-)). Thus these Mn-Salens have the potential to ameliorate cellular damage caused by both oxidative and nitrosative stresses, by the catalytic breakdown of O(2)(-), H(2)O(2), ONOO(-) and NO to benign species: O(2), H(2)O, NO(2)(-) and NO(3)(-). PMID:11994046

Sharpe, Martyn A; Ollosson, Richard; Stewart, Victoria C; Clark, John B



Hypoxia-induced upregulation of pigment epithelium-derived factor by retinal glial (Müller) cells.  


Neuronal degeneration and aberrant neovascularization are common problems of ischemic retinopathies. Pigment epithelium-derived factor (PEDF), a neuroprotective protein and an inhibitor of angiogenesis, is produced by retinal glial (Müller) cells and can counterbalance elevated levels of vascular endothelial growth factor (VEGF), the expression of which is regulated primarily by hypoxia-inducible factor (HIF)-1. In an approach to mimic transient ischemia in vitro, primary Müller cells were cultured under transient and strong hypoxia (0.2% O(2) ), followed by reoxygenation at 2.5% O(2) , and molecular mechanisms that might contribute to changes in the intraretinal PEDF level were determined. Hypoxic conditions caused an increasing expression of HIF-1? and led to upregulation of both PEDF and VEGF. Treatment of the cells with synthetic HIF-1? blockers or neutralization of VEGF binding to VEGF receptors (VEGFR-1 and-2) suppressed hypoxia-induced PEDF upregulation. Furthermore, the presence of CoCl(2) (a hypoxia mimetic) induced an accumulation of elevated HIF-1? protein in the nucleus and an upregulation of PEDF expression in Müller cells. Increasing PEDF expression was attenuated when HIF-1? levels were suppressed using HIF-1? small interfering RNA (siRNA). On the other hand, siRNA-mediated depletion of PEDF facilitated HIF-1? upregulation caused by CoCl(2) and resulted in increasing VEGF mRNA and protein levels. These results demonstrate that VEGF and PEDF may be unidirectionally regulated in hypoxia through HIF-1? activation, with upregulation of PEDF, which may occur in a VEGF-dependent manner. However, endogenously produced PEDF seems to be an inherent control element of HIF-1? expression in Müller cells, indicating an important feedback mechanism for limiting upregulation of VEGF. PMID:21922517

Yang, Xiu Mei; Yafai, Yousef; Wiedemann, Peter; Kuhrt, Heidrun; Wang, Yu-Sheng; Reichenbach, Andreas; Eichler, Wolfram



Chronic morphine treatment up-regulates mu opioid receptor binding in cells lacking filamin A.  


We investigated the effects of morphine and other agonists on the human mu opioid receptor (MOP) expressed in M2 melanoma cells, lacking the actin cytoskeleton protein filamin A and in A7, a subclone of the M2 melanoma cells, stably transfected with filamin A cDNA. The results of binding experiments showed that after chronic morphine treatment (24 h) of A7 cells, MOP-binding sites were down-regulated to 63% of control, whereas, unexpectedly, in M2 cells, MOP binding was up-regulated to 188% of control naive cells. Similar up-regulation was observed with the agonists methadone and levorphanol. The presence of antagonists (naloxone or CTAP) during chronic morphine treatment inhibited MOP down-regulation in A7 cells. In contrast, morphine-induced up-regulation of MOP in M2 cells was further increased by these antagonists. Chronic morphine desensitized MOP in A7 cells, i.e., it decreased DAMGO-induced stimulation of GTPgammaS binding. In M2 cells DAMGO stimulation of GTPgammaS binding was significantly greater than in A7 cells and was not desensitized by chronic morphine. Pertussis toxin treatment abolished morphine-induced receptor up-regulation in M2 cells, whereas it had no effect on morphine-induced down-regulation in A7 cells. These results indicate that, in the absence of filamin A, chronic treatment with morphine, methadone or levorphanol leads to up-regulation of MOP, to our knowledge, the first instance of opioid receptor up-regulation by agonists in cell culture. PMID:17897634

Onoprishvili, Irma; Simon, Eric J



Optimization of Rutaecarpine as ABCA1 Up-Regulator for Treating Atherosclerosis.  


ATP-binding cassette transporter A1 (ABCA1) is a key transporter and receptor in promoting cholesterol efflux, and increasing the expression level of ABCA1 is antiatherogenic. In our previous study, rutaecarpine (RUT) was found to protect ApoE(-/-) mice from developing atherosclerosis through preferentially up-regulating ABCA1 expression. In the present work, a series of RUT derivatives were synthesized and examined as ABCA1 expression up-regulators. Compounds CD1, CD6, and BCD1-2 were found to possess the most potential activity as antiatherosclerotic agents among all compounds tested. PMID:25147608

Li, Yongzhen; Feng, Tingting; Liu, Peng; Liu, Chang; Wang, Xiao; Li, Dongsheng; Li, Ni; Chen, Minghua; Xu, Yanni; Si, Shuyi



Pim kinases are upregulated during Epstein-Barr virus infection and enhance EBNA2 activity  

SciTech Connect

Latent Epstein-Barr virus (EBV) infection is strongly associated with B-cell proliferative diseases such as Burkitt's lymphoma. Here we show that the oncogenic serine/threonine kinases Pim-1 and Pim-2 enhance the activity of the viral transcriptional activator EBNA2. During EBV infection of primary B-lymphocytes, the mRNA expression levels of pim genes, especially of pim-2, are upregulated and remain elevated in latently infected B-cell lines. Thus, EBV-induced upregulation of Pim kinases and Pim-stimulated EBNA2 transcriptional activity may contribute to the ability of EBV to immortalize B-cells and predispose them to malignant growth.

Rainio, Eeva-Marja [Turku Centre for Biotechnology, University of Turku/Abo Akademi University, Tykistoekatu 6B, 20520 Turku (Finland); Turku Graduate School of Biomedical Sciences, 20520 Turku (Finland); Ahlfors, Helena [Turku Centre for Biotechnology, University of Turku/Abo Akademi University, Tykistoekatu 6B, 20520 Turku (Finland); Carter, Kara L. [Department of Medicine and Microbiology, Harvard Medical School, Boston, MA 02115 (United States); Department of Molecular Genetics, Harvard Medical School, Boston, MA 02115 (United States); Channing Laboratory, Brigham and Women's Hospital, Boston, MA 02115 (United States); Ruuska, Marja [Turku Centre for Biotechnology, University of Turku/Abo Akademi University, Tykistoekatu 6B, 20520 Turku (Finland); Matikainen, Sampsa [Turku Centre for Biotechnology, University of Turku/Abo Akademi University, Tykistoekatu 6B, 20520 Turku (Finland); Department of Microbiology, National Public Health Institute, Mannerheimintie 166, 00300 Helsinki (Finland); Kieff, Elliott [Department of Medicine and Microbiology, Harvard Medical School, Boston, MA 02115 (United States); Department of Molecular Genetics, Harvard Medical School, Boston, MA 02115 (United States); Channing Laboratory, Brigham and Women's Hospital, Boston, MA 02115 (United States); Koskinen, Paeivi J. [Turku Centre for Biotechnology, University of Turku/Abo Akademi University, Tykistoekatu 6B, 20520 Turku (Finland)]. E-mail:



COMBINED BIOCHEMICAL AND MORPHOLOGICAL STUDY OF PARTICULATE FRACTIONS FROM RAT LIVER: Analysis of Preparations Enriched in Lysosomes or in Particles Containing Urate Oxidase, D-Amino Acid Oxidase, and Catalase  

Microsoft Academic Search

Six particulate preparations isolated from rat liver under different experimental condi- tions were analyzed biochemically and examined in the electron microscope. The results confirm the lysosomal nature of the pericanalicular dense bodies and demonstrate that the microbodics arc the bearers of urate oxidase, catalase, and D-amino acid oxidasc. Catalasc, representing a major component of the particles, and D-amino acid oxidase





Technology Transfer Automated Retrieval System (TEKTRAN)

The incidence of type 2 diabetes (T2D) increases with age. Low-grade inflammation in AT is implicated in development of insulin resistance and T2D. This study investigated if inflammatory responses are up-regulated with age in AT. Results showed that visceral AT from old mice have higher mRNA expres...


Testosterone protects against dexamethasone-induced muscle atrophy, protein degradation and MAFbx upregulation  

Microsoft Academic Search

Administration of glucocorticoids in pharmacological amounts results in muscle atrophy due, in part, to accelerated degradation of muscle proteins by the ubiquitin–proteasome pathway. The ubiquitin ligase MAFbx is upregulated during muscle loss including that caused by glucocorticoids and has been implicated in accelerated muscle protein catabolism during such loss. Testosterone has been found to reverse glucocorticoid-induced muscle loss due to

Weidong Zhao; Jiangping Pan; Zingbo Zhao; Yong Wu; William A. Bauman; Christopher P. Cardozo



RESEARCH ARTICLE Open Access EMMPRIN/CD147 up-regulates urokinase-type  

E-print Network

RESEARCH ARTICLE Open Access EMMPRIN/CD147 up-regulates urokinase-type plasminogen activatorPA contributes to EMMPRIN's effect in promoting oral tumor invasion. Keywords: EMMPRIN/CD147, uPA, Oral squamous to involve the intervention of proteinases [3-5]. Extracellular matrix metalloproteinase inducer (EMMPRIN/CD

Paris-Sud XI, Université de


Sox6 Up-Regulation by Macrophage Migration Inhibitory Factor Promotes Survival and Maintenance of Mouse  

E-print Network

is inhibited by Sox6 gene silencing. Collectively, our data identify Sox6 as an important downstream effector University. The funders had no role in study design, data collection and analysis, decision to publishSox6 Up-Regulation by Macrophage Migration Inhibitory Factor Promotes Survival and Maintenance


Cotton Benzoquinone Reductase: Up-regulation During Early Cotton Fiber Developement  

Technology Transfer Automated Retrieval System (TEKTRAN)

Benzoquinone reductase (BR; EC is an enzyme that catalyzes the bivalent redox reactions of quinones without the production of free radical intermediates. Using 2-D PAGE comparisons, two proteins were found to be up-regulated in wild-type cotton ovules during the fiber initiation stage but ...


Long-lasting dopamine receptor up-regulation in amphetamine-treated rats following amphetamine neurotoxicity.  


Amphetamine (A) (9.2 mg/kg, IP), in combination with iprindole (I) (10.0 mg/kg, IP), caused long-lasting dopamine (DA) depletions in striatum (-49%, 4 weeks) but not in nucleus accumbens following one A/I injection. Striatal DA had recovered by 4 months. DA receptors (DAr) were up-regulated: 1) behavioral responses to a DA receptor agonist (apomorphine) were significantly elevated. These included apomorphine-induced locomotor activity (+103% and +160%, on weeks 3 and 10) and apomorphine-induced stereotypy (day 10). 2) Bmax for [3H]spiroperidol binding to striatal D2 DAr (12 weeks) increased (+53%, week 12). Injection of the DAr neuromodulator cyclo(leucyl-glycyl) (8 mg/kg/day x 4 days, SC) reversed the Bmax increase. Thus toxicity (DA depletion) following high-dose amphetamine appears to induce compensatory changes in DAr. This DAr upregulation may explain the lack of abnormal movements despite enduring DA depletion. Additionally, the A/I paradigm as an animal model of long-lasting DAr up-regulation, could be used to screen neuromodulatory agents, like CLG, that might treat disorders (e.g., tardive dyskinesia and schizophrenia) thought to involve up-regulated DAr. PMID:1816575

Fields, J Z; Wichlinski, L; Drucker, G E; Engh, K; Gordon, J H



Upregulation of cathepsin S in psoriatic keratinocytes Alexander Scho nefu1  

E-print Network

skin biopsies, i.e. atopic dermatitis, actinic keratosis and psoriasis, CATS staining is strongly increased in the dermis. But only in psoriasis, CATS- immunostaining is also detectable in keratinocytes. We ­ psoriasis ­ T-cell Please cite this paper as: Upregulation of cathepsin S in psoriatic keratinocytes

Lübbert, Hermann


Transcriptional profiling identifies upregulated genes following induction of epithelial-mesenchymal transition in squamous carcinoma cells.  


During the progression of head and neck squamous cell carcinoma (HNSCC), the induction of an epithelial-mesenchymal transition (EMT) program may play a critical role in the dissemination of cells from the primary tumor to distant metastatic foci. The process of EMT involves the activation of several important genes and pathways to help maintain survival and growth and evolve into highly invasive and metastatic variants. In this study, expression microarray analysis identified a set of 145 upregulated genes in EMT-like HNSCC cells. Some of the strongly upregulated transcripts include genes that are reportedly involved in invasion and metastasis, such as DOCK10, LOX, ROBO1 and SRGN. Importantly, the Tbx3 gene, a member of the T-box transcription factor, was strongly upregulated in SCC cells displaying an EMT-like phenotype compared to cells with an epitheloid, non-EMT behavior. Tbx3 was also found to be strongly upregulated at the protein and gene expression level in an experimental model of snail-induced EMT cells. In addition, siRNA-induced Tbx3 depletion modestly suppressed cell invasion while enhancing Tbx3-mediated resistance to anoikis. Our findings provide evidence that Tbx3 overexpression promotes SCC cell survival displaying an EMT phenotype. This set of newly identified genes that are modulated during EMT-like conversion may be important diagnostic biomarkers during the process of HNSCC progression. PMID:22154512

Humtsoe, Joseph O; Koya, Eriko; Pham, Eric; Aramoto, Takayoshi; Zuo, Jian; Ishikawa, Tohru; Kramer, Randall H



Selective upregulation of scavenger receptors in and around demyelinating areas in multiple sclerosis.  


Autoantibodies and complement opsonization have been implicated in the process of demyelination in the major human CNS demyelinating disease multiple sclerosis (MS), but scavenger receptors (SRs) may also play pathogenetic roles. We characterized SR mRNA and protein expression in postmortem brain tissue from 13 MS patients in relation to active demyelination. CD68, chemokine (C-X-C motif) ligand 16 (CXCL16), class A macrophage SR (SR-AI/II), LOX-1 (lectin-like oxidized low-density lipoprotein receptor 1), Fc?RIII, and LRP-1 (low-density lipoprotein receptor-related protein 1) mRNA were upregulated in the rims of chronic active MS lesions. CD68 and CXCL16 mRNA were also upregulated around chronic active MS lesions. By immunohistochemistry, CD68, CXCL16, and SR-AI/II were expressed by foamy macrophages in the rim and by ramified microglia around chronic active MS lesions. CXCL16 and SR-AI/II were also expressed by astrocytes in MS lesions and by primary human microglia and astrocytes in vitro. These data suggest that SRs are involved in myelin uptake in MS, and that upregulation of CD68, CXCL16, and SR-AI/II is one of the initial events in microglia as they initiate myelin phagocytosis. As demyelination continues, additional upregulation of LOX-1, Fc?RIII, and LRP-1 may facilitate this process. PMID:23334594

Hendrickx, Debbie A E; Koning, Nathalie; Schuurman, Karianne G; van Strien, Miriam E; van Eden, Corbert G; Hamann, Jörg; Huitinga, Inge



FoxM1 Is Up-Regulated by Obesity and Stimulates -Cell Proliferation  

E-print Network

FoxM1 Is Up-Regulated by Obesity and Stimulates -Cell Proliferation Dawn Belt Davis,* Jeremy A of Statistics (B.S.Y.), University of Wisconsin, Madison, Wisconsin; and Merck Research Laboratories (I.-M.W., E.E.S.), Rahway, New Jersey -Cell mass expansion is one mechanism by which obese animals compensate for insulin

Yandell, Brian S.


Mouse strains that lack spinal dynorphin upregulation after peripheral nerve injury do not develop neuropathic pain  

Microsoft Academic Search

Several experimental models of peripheral neuropathy show that a significant upregulation of spinal dynorphin A and its precursor peptide, prodynorphin, is a common consequence of nerve injury. A genetically modified mouse strain lacking prodynorphin does not exhibit sustained neuropathic pain after nerve injury, supporting a pronociceptive role of elevated levels of spinal dynorphin. A null mutation of the ? isoform




Sucrose prevents up-regulation of senescence-associated genes in carnation petals.  


cDNA microarrays were used to characterize senescence-associated gene expression in petals of cut carnation (Dianthus caryophyllus) flowers, sampled from anthesis to the first senescence symptoms. The population of PCR fragments spotted on these microarrays was enriched for flower-specific and senescence-specific genes, using subtractive hybridization. About 90% of the transcripts showed a large increase in quantity, approximately 25% transiently, and about 65% throughout the 7 d experiment. Treatment with silver thiosulphate (STS), which blocks the ethylene receptor and prevented the normal senescence symptoms, prevented the up-regulation of almost all of these genes. Sucrose treatment also considerably delayed visible senescence. Its effect on gene expression was very similar to that of STS, suggesting that soluble sugars act as a repressor of ethylene signal transduction. Two fragments that encoded a carnation EIN3-like (EIL) protein were isolated, some of which are key transcription factors that control ethylene response genes. One of these (Dc-EIL3) was up-regulated during senescence. Its up-regulation was delayed by STS and prevented by sucrose. Sucrose, therefore, seems to repress ethylene signalling, in part, by preventing up-regulation of Dc-EIL3. Some other transcription factors displayed an early increase in transcript abundance: a MYB-like DNA binding protein, a MYC protein, a MADS-box factor, and a zinc finger protein. Genes suggesting a role in senescence of hormones other than ethylene encoded an Aux/IAA protein, which regulate transcription of auxin-induced genes, and a cytokinin oxidase/dehydrogenase, which degrades cytokinin. Taken together, the results suggest a master switch during senescence, controlling the co-ordinated up-regulation of numerous ethylene response genes. Dc-EIL3 might be (part of) this master switch. PMID:17630294

Hoeberichts, Frank A; van Doorn, Wouter G; Vorst, Oscar; Hall, Robert D; van Wordragen, Monique F



Constitutive upregulation of the transforming growth factor-? pathway in rheumatoid arthritis synovial fibroblasts  

PubMed Central

Genome-wide gene expression was comparatively investigated in early-passage rheumatoid arthritis (RA) and osteoarthritis (OA) synovial fibroblasts (SFBs; n = 6 each) using oligonucleotide microarrays; mRNA/protein data were validated by quantitative PCR (qPCR) and western blotting and immunohistochemistry, respectively. Gene set enrichment analysis (GSEA) of the microarray data suggested constitutive upregulation of components of the transforming growth factor (TGF)-? pathway in RA SFBs, with 2 hits in the top 30 regulated pathways. The growth factor TGF-?1, its receptor TGFBR1, the TGF-? binding proteins LTBP1/2, the TGF-?-releasing thrombospondin 1 (THBS1), the negative effector SkiL, and the smad-associated molecule SARA were upregulated in RA SFBs compared to OA SFBs, whereas TGF-?2 was downregulated. Upregulation of TGF-?1 and THBS1 mRNA (both positively correlated with clinical markers of disease activity/severity) and downregulation of TGF-?2 mRNA in RA SFBs were confirmed by qPCR. TGFBR1 mRNA (only numerically upregulated in RA SFBs) and SkiL mRNA were not differentially expressed. At the protein level, TGF-?1 showed a slightly higher expression, and the signal-transducing TGFBR1 and the TGF-?-activating THBS1 a significantly higher expression in RA SFBs than in OA SFBs. Consistent with the upregulated TGF-? pathway in RA SFBs, stimulation with TGF-?1 resulted in a significantly enhanced expression of matrix-metalloproteinase (MMP)-11 mRNA and protein in RA SFBs, but not in OA SFBs. In conclusion, RA SFBs show broad, constitutive alterations of the TGF-? pathway. The abundance of TGF-?, in conjunction with an augmented mRNA and/or protein expression of TGF-?-releasing THBS1 and TGFBR1, suggests a pathogenetic role of TGF-?-induced effects on SFBs in RA, for example, the augmentation of MMP-mediated matrix degradation/remodeling. PMID:17594488

Pohlers, Dirk; Beyer, Andreas; Koczan, Dirk; Wilhelm, Thomas; Thiesen, Hans-Jürgen; Kinne, Raimund W



Cell Autonomy, Receptor Autonomy, and Thermodynamics in Nicotine Receptor Up-regulation  

PubMed Central

Chronic nicotine exposure, in smokers or in experimental rodents administered nicotine, produces elevated levels of nicotinic acetylcholine receptors in several brain regions. However, there are few data on up-regulation of receptors in specific neuronal subtypes. We tested whether functional up-regulation of nicotinic responses occurs in cultured GABAergic neurons of the ventral midbrain. Fura-2 measurements of nicotinic responses were made on ventral midbrain neurons from knock-in mice heterozygous for the ?4-M2 domain Leu9'Ala mutation, which confers nicotine hypersensitivity. Chronic nicotine exposure at a concentration (10 nM for 3 days) that activates only the hypersensitive ?4*(Leu 9' Ala) receptors, but not wild-type receptors, resulted in significant potentiation of ACh (100 ?M)-elicited responses. Experiments were also performed on midbrain neuronal cultures heterozygous for the ?4*(Leu9'Ala) mutation as well as for a GFP protein fused to a GABA transporter that reliably reveals GABAergic neurons. In cultures chronically treated with 10 nM nicotine, there was significantly increased ?4* nicotinic-induced Ca2+ influx elicited by low concentration of ACh (3 ?M). Furthermore, chronic exposure to the competitive antagonist dihydro-?-erythroidine, but not to the noncompetitive antagonist mecamylamine, induced up-regulation of ACh elicited nicotinic responses. These results suggest that occupation of ?4* nicotinic receptor binding site(s), at the interface between two subunits, is sufficient to promote assembly and/or up-regulation of functional receptors in GABAergic neurons. Up-regulation in neurons is both “cell-autonomous”, occurring at the cell itself, and “receptor autonomous”, occurring at the receptor itself, and may be a thermodynamic necessity of ligand-protein interactions. PMID:17662697

Nashmi, Raad; Lester, Henry



Rapid upregulation of heart antioxidant enzymes during arousal from estivation in the Giant African snail (Achatina fulica)  

E-print Network

Rapid upregulation of heart antioxidant enzymes during arousal from estivation in the Giant African by upregulating intracellular antioxidant defenses in the heart, kidney, hepatopancreas and foot tissues increased in heart, hepatopancreas and foot. In heart, a rapid increase in MnSOD protein levels was observed

Tattersall, Glenn


Mitochondria-targeted catalase reduces abnormal APP processing, amyloid ? production and BACE1 in a mouse model of Alzheimer's disease: implications for neuroprotection and lifespan extension.  


The purpose of this study was to investigate the protective effects of the mitochondria-targeted antioxidant catalase (MCAT) and lifespan extension in mice that express amyloid beta (A?). Using immunoblotting and immunostaining analyses, we measured the production of full-length amyloid precursor protein (APP), soluble APP?, C-terminal fragments CTF99 and CTF83, monomeric and oligomeric A?, A? deposits and beta site amyloid precursor protein cleaving enzyme 1 (BACE1), in different stages of disease progression in MCAT/A?PP and A?PP mice. Using quantitative reverse transcriptase polymerase chain reaction and immunostaining analyses, we studied the expression of catalase, BACE1, the Alzheimer's disease (AD) markers, synaptophysin, APP, neprilysin, insulin-degrading enzyme and transthyretin in MCAT, A?PP, MCAT/A?PP and wild-type (WT) mice. Using the high pressure liquid chromatography analysis of 8-hydroxy-2-deoxyguanosine, we measured oxidative DNA damage in the cerebral cortical tissues from MCAT, A?PP, MCAT/A?PP and WT mice. We found that the A?PP transgenic mice that carried the human MCAT gene lived 5 months longer than did the A?PP mice. We also found that the overexpression of MCAT in the brain sections from the MCAT/A?PP transgenic mice significantly correlated with a reduction in the levels of full-length APP, CTF99, BACE1, A? levels (40 and 42), A? deposits and oxidative DNA damage relative to the brain sections from the A?PP mice. Interestingly, we found significantly increased levels of soluble APP? and CTF83 in the MCAT/A?PP mice, relative to the A?PP mice. These data provide direct evidence that oxidative stress plays a primary role in AD etiopathology and that in MCAT mice express A?, MCAT prevents abnormal APP processing, reduces A? levels and enhances A?-degrading enzymes in mice at different ages, corresponding to different stages of disease progression. These findings indicate that mitochondria-targeted molecules may be an effective therapeutic approach to treat patients with AD. PMID:22492996

Mao, Peizhong; Manczak, Maria; Calkins, Marcus J; Truong, Quang; Reddy, Tejaswini P; Reddy, Arubala P; Shirendeb, Ulziibat; Lo, Herng-Hsiang; Rabinovitch, Peter S; Reddy, P Hemachandra



Upregulation of early growth response factor-1 by bile acids requires mitogen-activated protein kinase signaling  

SciTech Connect

Cholestasis results when excretion of bile acids from the liver is interrupted. Liver injury occurs during cholestasis, and recent studies showed that inflammation is required for injury. Our previous studies demonstrated that early growth response factor-1 (Egr-1) is required for development of inflammation in liver during cholestasis, and that bile acids upregulate Egr-1 in hepatocytes. What remains unclear is the mechanism by which bile acids upregulate Egr-1. Bile acids modulate gene expression in hepatocytes by activating the farnesoid X receptor (FXR) and through activation of mitogen-activated protein kinase (MAPK) signaling. Accordingly, the hypothesis was tested that bile acids upregulate Egr-1 in hepatocytes by FXR and/or MAPK-dependent mechanisms. Deoxycholic acid (DCA) and chenodeoxycholic acid (CDCA) stimulated upregulation of Egr-1 to the same extent in hepatocytes isolated from wild-type mice and FXR knockout mice. Similarly, upregulation of Egr-1 in the livers of bile duct-ligated (BDL) wild-type and FXR knockout mice was not different. Upregulation of Egr-1 in hepatocytes by DCA and CDCA was prevented by the MEK inhibitors U0126 and SL-327. Furthermore, pretreatment of mice with U0126 prevented upregulation of Egr-1 in the liver after BDL. Results from these studies demonstrate that activation of MAPK signaling is required for upregulation of Egr-1 by bile acids in hepatocytes and for upregulation of Egr-1 in the liver during cholestasis. These studies suggest that inhibition of MAPK signaling may be a novel therapy to prevent upregulation of Egr-1 in liver during cholestasis.

Allen, Katryn [Department of Pharmacology, Toxicology, and Experimental Therapeutics, University of Kansas Medical Center, 4063 KLSIC, 3901 Rainbow Boulevard, Kansas City, KS 66160 (United States); Kim, Nam Deuk; Moon, Jeon-OK [Department of Pharmacology, Toxicology, and Experimental Therapeutics, University of Kansas Medical Center, 4063 KLSIC, 3901 Rainbow Boulevard, Kansas City, KS 66160 (United States); Department of Pharmacy, Pusan National University, Busan 609-735 (Korea, Republic of); Copple, Bryan L., E-mail: bcopple@kumc.ed [Department of Pharmacology, Toxicology, and Experimental Therapeutics, University of Kansas Medical Center, 4063 KLSIC, 3901 Rainbow Boulevard, Kansas City, KS 66160 (United States)



Sesamin modulates tyrosine hydroxylase, superoxide dismutase, catalase, inducible NO synthase and interleukin-6 expression in dopaminergic cells under MPP+-induced oxidative stress  

PubMed Central

Oxidative stress is regarded as a mediator of nerve cell death in several neurodegenerative disorders, such as Parkinson's disease. Sesamin, a lignan mainly found in sesame oil, is currently under study for its anti-oxidative and possible neuroprotective properties. We used 1-methyl-4-phenyl-pyridine (MPP+) ion, the active metabolite of the potent parkinsonism-causing toxin 1-methyl-4-phenyl-1,2,5,6-tetrahydropyridine, to produce oxidative stress and neurodegeneration in neuronal PC12 cells, which express dopamine, as well as neurofilaments. Our results show that picomolar doses of sesamin protected neuronal PC12 cells from MPP+-induced cellular death, as revealed by colorimetric measurements and production of reactive oxygen species. We also demonstrated that sesamin acted by rescuing tyrosine hydroxylase levels from MPP+-induced depletion. Sesamin, however, did not modulate dopamine transporter levels, and estrogen receptor-alpha and -beta protein expression. By examining several parameters of cell distress, we found that sesamin also elicited a strong increase in superoxide dismutase activity as well as protein expression and decreased catalase activity and the MPP+ stimulated inducible nitric oxide synthase protein expression, in neuronal PC12 cells. Finally, sesamin possessed significant anti-inflammatory properties, as disclosed by its potential to reduce MPP+-induced interleukin-6 mRNA levels in microglia. From these studies, we determined the importance of the lignan sesamin as a neuroprotective molecule and its possible role in complementary and/or preventive therapies of neurodegenerative diseases. PMID:19794909

Lahaie-Collins, Vicky; Bournival, Julie; Plouffe, Marilyn; Carange, Julie



Orally supplemented catechin increases heme amounts and catalase activities in rat heart blood mitochondria: a comparison between middle-aged and young rats.  


Orally-administered catechin has long been known to have several beneficial effects on the mammalian host, however, the effects of orally supplemented catechin on the host through gingival tissues have not yet been established. Here, we elucidated the effects of orally supplemented catechin in the rat heart blood mitochondria. We used middle-aged (40 week-old) and young (4 week-old) rats throughout the study. We indirectly verified blood serum catechin levels by measuring O-methyl catechin derivatives using HPLC. Interestingly, we observed higher blood serum O-methyl levels in middle-aged rats as compared to young rats. Subsequently, we isolated blood mitochondria, verified its purity, and measured heme, hydrogen peroxide, and catalase (CAT) levels. We found that catechin induces an increase in blood mitochondrial heme amounts and is associated with an increase in blood mitochondrial CAT activity which is surprisingly higher in middle-aged rats as compared to young rats. This would imply that orally supplemented catechin induces heme increase that preferentially favours CAT activity and is more beneficial to the middle-aged rats. PMID:24004580

Cueno, Marni E; Tamura, Muneaki; Imai, Kenichi; Ochiai, Kuniyasu



Allofustis seminis gen. nov., sp. nov., a novel Gram-positive, catalase-negative, rod-shaped bacterium from pig semen.  


An unknown Gram-positive, catalase-negative, facultatively anaerobic, non-spore-forming, rod-shaped bacterium originating from semen of a pig was characterized using phenotypic, molecular chemical and molecular phylogenetic methods. Chemical studies revealed the presence of a directly cross-linked cell wall murein based on L-lysine and a DNA G + C content of 39 mol%. Comparative 16S rRNA gene sequencing showed that the unidentified rod-shaped organism formed a hitherto unknown subline related, albeit loosely, to Alkalibacterium olivapovliticus, Alloiococcus otitis, Dolosigranulum pigrum and related organisms, in the low-G + C-content Gram-positive bacteria. However, sequence divergence values of > 11% from these recognized taxa clearly indicated that the novel bacterium represents a separate genus. Based on phenotypic and phylogenetic considerations, it is proposed that the unknown bacterium from pig semen be classified as a new genus and species, Allofustis seminis gen. nov., sp. nov. The type strain is strain 01-570-1(T) (= CCUG 45438(T) = CIP 107425(T)). PMID:12807205

Collins, Matthew D; Higgins, Robert; Messier, Serge; Fortin, Madeleine; Hutson, Roger A; Lawson, Paul A; Falsen, Enevold



Atopococcus tabaci gen. nov., sp. nov., a novel Gram-positive, catalase-negative, coccus-shaped bacterium isolated from tobacco.  


A novel Gram-positive, aerobic, catalase-negative, coccus-shaped organism originating from tobacco was characterized using phenotypic and molecular taxonomic methods. The organism contained a cell wall murein based on L-lysine (variation A4alpha, type L-lysine-L-glutamic acid), synthesized long-chain cellular fatty acids of the straight-chain saturated and monounsaturated types (with C(16:1)omega9, C(16:0) and C(18:1)omega9 predominating) and possessed a DNA G+C content of 46 mol%. Based on morphological, biochemical and chemical characteristics, the coccus-shaped organism did not conform to any presently recognized taxon. Comparative 16S rRNA gene sequencing studies confirmed the distinctiveness of the unknown coccus, with the bacterium displaying sequence divergence values of greater than 7% with other recognized Gram-positive taxa. Treeing analysis reinforced its distinctiveness, with the unidentified organism forming a relatively long subline branching at the periphery of an rRNA gene sequence cluster which encompasses the genera Alloiococcus, Allofustis, Alkalibacterium, Atopostipes, Dolosigranulum and Marinilactibacillus. Based on phenotypic and molecular phylogenetic evidence, it is proposed that the unknown organism from tobacco be classified as a new genus and species, Atopococcus tabaci gen. nov., sp. nov. The type strain of Atopococcus tabaci is CCUG 48253(T) (=CIP 108502(T)). PMID:16014503

Collins, Matthew D; Wiernik, Anna; Falsen, Enevold; Lawson, Paul A



Induction of the Viable but Nonculturable State of Ralstonia solanacearum by Low Temperature in the Soil Microcosm and Its Resuscitation by Catalase  

PubMed Central

Ralstonia solanacearum is the causal agent of bacterial wilt on a wide variety of plants, and enters a viable but nonculturable (VBNC) state under stress conditions in soil and water. Here, we adopted an artificial soil microcosm (ASM) to investigate the VBNC state of R. solanacearum induced by low temperature. The culturability of R. solanacearum strains SL341 and GMI1000 rapidly decreased at 4°C in modified ASM (mASM), while it was stably maintained at 25°C in mASM. We hypothesized that bacterial cells at 4°C in mASM are viable but nonculturable. Total protein profiles of SL341 cells at 4°C in mASM did not differ from those of SL341 culturable cells at 25°C in mASM. Moreover, the VBNC cells maintained in the mASM retained respiration activity. Catalase treatment effectively restored the culturability of nonculturable cells in mASM, while temperature increase or other treatments used for resuscitation of other bacteria were not effective. The resuscitated R. solanacearum from VBNC state displayed normal level of bacterial virulence on tomato plants compared with its original culturable bacteria. Expression of omp, oxyR, rpoS, dps, and the 16S rRNA gene quantified by RT-qPCR did not differ significantly between the culturable and VBNC states of R. solanacearum. Our results suggested that the VBNC bacterial cells in mASM induced by low temperature exist in a physiologically unique state. PMID:25296177

Kong, Hyun Gi; Bae, Ju Young; Lee, Hyoung Ju; Joo, Hae Jin; Jung, Eun Joo; Chung, Eunsook; Lee, Seon-Woo



Binding of the antitubercular pro-drug isoniazid in the heme access channel of catalase-peroxidase (KatG). A combined structural and metadynamics investigation.  


Isonicotinic acid hydrazide (isoniazid or INH) is a front line antitubercular pro-drug that is converted to its active form, isonicotinyl-NAD, by the bacterial catalase-peroxidase KatG. Understanding the role of KatG in the INH activation process has been hampered by a lack of knowledge of the actual drug binding site. In this work, we have investigated the binding of INH in the main access channel of KatG with a combination of molecular dynamics, using an enhanced-sampling technique (metadynamics), X-ray crystallography, and site-directed mutagenesis. The metadynamics simulations show that there are several weak drug binding sites along the access channel. Moreover, the simulations evidence that complete entrance to the heme active site is impeded by an aspartate residue (D141) located above the heme. This has been confirmed by structural and functional analysis of the D141A mutant, leading to the first X-ray crystallography evidence of INH at the heme access channel. PMID:24568093

Vidossich, Pietro; Loewen, Peter C; Carpena, Xavi; Fiorin, Giacomo; Fita, Ignacio; Rovira, Carme



RNAi-Mediated Knockdown of Catalase Causes Cell Cycle Arrest in SL-1 Cells and Results in Low Survival Rate of Spodoptera litura (Fabricius)  

PubMed Central

Deregulated reactive oxygen species (ROS) production can lead to the disruption of structural and functional integrity of cells as a consequence of reactive interaction between ROS and various biological components. Catalase (CAT) is a common enzyme existing in nearly all organisms exposed to oxygen, which decomposes harmful hydrogen peroxide, into water and oxygen. In this study, the full length sequence that encodes CAT-like protein from Spodoptera litura named siltCAT (GenBank accession number: JQ_663444) was cloned and characterized. Amino acid sequence alignment showed siltCAT shared relatively high conservation with other insect, especially the conserved residues which defined heme and NADPH orientation. Expression pattern analysis showed that siltCAT mRNA was mainly expressed in the fat body, midgut, cuticle and malpighian tube, and as well as over last instar larvae, pupa and adult stages. RNA interference was used to silence CAT gene in SL-1 cells and the fourth-instar stage of S. litura larvae respectively. Our results provided evidence that CAT knockdown induced ROS generation, cell cycle arrest and apoptosis in SL-1 cells. It also confirmed the decrease in survival rate because of increased ROS production in experimental groups injected with double-stranded RNA of CAT (dsCAT). This study implied that ROS scavenging by CAT is important for S. litura survival. PMID:23555693

Hu, Meiying; Chen, Shaohua; Muhammad, Rizwan-ul-Haq; Dong, Xiaolin; Gong, Liang



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

PubMed Central

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. PMID:24987414

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



Biological applications and effects of optical masers. Annual report, 16 March 1985-15 March 1986. [Superoxide dismutase and catalase injected intravenously  

SciTech Connect

Evidence that superoxide dismutase (SOD) enhances and catalase (CAT) reduces blue light toxicity in the monkey retina when injected intravenously (i.v) was inconclusive, and it is surmized that i.v. injection is ineffective because these large enzymes have a short lifetime in the circulation and cannot penetrate the blood-retinal barrier. Repetitive eye exposures of trained monkeys to the borad spectrum 330-420 nm were terminated in February 1985 after 1,171 daily exposures in one animal and 584 in the other animal. To date, no lenticular anomalies have been noted. Both monkeys are being maintained in good health and examined with the biomicroscope at frequent intervals. Repetitive daily exposures for 21 days of 440, 475, and 533 nm light at the same retinal site in 3 monkeys have shown that photic maculopathy is cumulative on a daily basis, especially for 440-nm light. In one monkey, daily radiant exposures of 2.8 -2/ resulted in the appearance of a lesion on the 20th day. Histologic data are presented for retinal lesions produced by 40-microsecond pulses of 647-nm laser light at a pulse repetition frequency (PRF) of 1600 Hz. Exposures were 10 s in duration at a peak power to the cornea of the monkey eye of 43 nW. The results are unusual in that the photoreceptors above the reinal pigment epithelium (RPE) are completely ablated. Possible mechanisms are discussed.

Ham, W.T.; Mueller, H.A.; Ruffolo, J.J.; Cleary, S.F.; Guerry, R.K.



Triazophos up-regulated gene expression in the female brown planthopper, Nilaparvata lugens.  


The widespread use of insecticides has caused the resurgence of the brown planthopper, Nilaparvata lugens, in Asia. In this study, we investigated an organo-phosphorous insecticide, triazophos, and its ability to induce gene expression variation in female N. lugens nymphs just before emergence. By using the suppression subtractive hybridization method, a triazophos-induced cDNA library was constructed. In total, 402 differentially expressed cDNA clones were obtained. Real-time qPCR analysis confirmed that triazophos up-regulated the expression of six candidate genes at the transcript level in nymphs on day 3 of the 5th instar. These genes encode N. lugens vitellogenin, bystin, multidrug resistance protein (MRP), purine nucleoside phosphorylase (PNP), pyrroline-5-carboxylate reductase (P5CR) and carboxylesterase. Our results imply that the up-regulation of these genes may be involved in the induction of N. lugens female reproduction or resistance to insecticides. PMID:20223245

Bao, Yan-Yuan; Li, Bao-Ling; Liu, Zhao-Bu; Xue, Jian; Zhu, Zeng-Rong; Cheng, Jia-An; Zhang, Chuan-Xi



Up-regulation of cyclooxygenase-2 by product-prostaglandin E2  

NASA Technical Reports Server (NTRS)

The development of prostate cancer has been linked to high level of dietary fat intake. Our laboratory investigates the connection between cancer cell growth and fatty acid products. Studying human prostatic carcinoma PC-3 cells, we found that prostaglandin E2 (PGE2) increased cell growth and up-regulated the gene expression of its own synthesizing enzyme, cyclooxygenase-2 (COX-2). PGE2 increased COX-2 mRNA expression dose-dependently with the highest levels of stimulation seen at the 3-hour period following PGE2 addition. The NSAID flurbiprofen (5 microM), in the presence of exogenous PGE2, inhibited the up-regulation of COX-2 mRNA and cell growth. These data suggest that the levels of local intracellular PGE2 play a major role in the growth of prostate cancer cells through an activation of COX-2 gene expression.