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[Relationship between catalase activity, KatG gene and isoniazid-resistance in M. tuberculosis].

OBJECTIVE: To investigate the relationship between catalase activity, KatG gene, gene mutation and INH-resistance in M. tuberculosis. METHOD: Catalase activities in 58 M. tuberculosis isolates were tested, and KatG gene mutations were detected further by PCR-SSCP. RESULT: None of INH-sensitive isolates lacked KatG sequences and all expressed catalase. 8(25%) INH-resistant isolates did not express catalase and 3(10%) lacked KatG gene, most of which were strains of high levels of resistance (MIC > 50 micrograms/ml). 8 INH-resistant isolates were analyzed further by PCR-SSCP and all were found to have KatG gene mutation. CONCLUSION: These findings indicated that lacking of catalase activity and KatG gene deletion occurred mainly in those highly INH-resistant strains, gene mutation other than complete deletion of KatG gene may be the major mechanism of INH-resistance.

Antitubercular Agents↗

Modulation of catalase in human skin in vivo by acute and chronic UV radiation.

In this study, we demonstrate that catalase is differently regulated either by acute, or chronic UV radiation during the photoaging process. 2MED of UV radiation decreased the activity and expression of catalase gradually in the epidermis and dermis at between 24 and 48 h after the UV exposure. These levels then returned to near normal by 72 h after exposure. The catalase mRNA was also decreased in the skin 24 h after UV irradiation to 50% of the control level, and then started to recover. In contrast, chronic UV irradiation over a lifetime (approximately 50 years) increased the catalase activity in the epidermis and dermis of the human skin in vivo. Our results suggest that catalase might be one of the important enzymes in the skin aging process, and that it plays an important role in the photoprotection of the skin from UV light.

Adult↗

Cytoprotective antioxidant activity of serum albumin and autocrine catalase in chronic lymphocytic leukaemia.

Chronic lymphocytic leukaemia (CLL) cells are long lived in vivo but undergo spontaneous apoptosis when cultured in vitro. Intriguingly, CLL cells also appear to have a specific susceptibility to oxidative stress - a potent inducer of apoptosis. Here, we show that serum albumin can function as a cytoprotective antioxidant of potential relevance to circulating CLL cells, and that autocrine catalase - a hydrogen peroxide-inactivating enzyme that may be released extracellularly - can perform a similar role under the crowded conditions that prevail at sites of tissue involvement. Albumin lowered oxidative stress in cultured CLL cells and inhibited spontaneous and reactive oxidant-induced apoptosis. Maximal effects were observed at a concentration of 10 mg/ml - fourfold lower than that in plasma and twofold higher than that in standard culture medium containing 10% fetal calf serum. Oxidative stress and spontaneous apoptosis were also decreased by cell crowding and by conditioned medium (CM) from crowded CLL cells, indicating that these processes were subject to autocrine regulation. CLL cells were found to express catalase and release enzyme activity into the culture medium. Exogenous catalase decreased oxidative stress and spontaneous apoptosis, and the anti-apoptotic effect of CM from crowded CLL cells was abrogated by the specific catalase inhibitor, 3'-amino-1,2,4-triazole. Together, these data strongly implicate autocrine catalase as a cytoprotective antioxidant. Oxidative stress in CLL cells was greatly diminished by ruthenium red - an inhibitor of mitochondrial reactive oxidant production - and by the glutathione (GSH) precursor N-acetylcysteine, suggesting that the GSH peroxidase antioxidant system may be compromised by lack of available substrate. Our findings highlight the importance of endogenous reactive oxidants in regulating CLL-cell apoptosis, and help to explain why CLL cells survive for prolonged periods in vivo despite their vulnerability to oxidative stress and spontaneous apoptosis when cultured in vitro.

Acetylcysteine↗

[Comparative study of the influence of yeast mannans on the rate of catalase synthesis in the liver of rats].

The effect of polysaccharides from Rh. rubra and Rh. mucilaginosa was studied as applied to the rate of catalase synthesis in rat liver. The constants were calculated for the rates of catalase synthesis and destruction. Yeast's mannan from Rh. mucilaginosa does not practically affect the rate of catalase synthesis. The mannan from Rh. rubra produces an almost three-fold inhibition on the catalase synthesis and the degree of the enzyme synthesis recovery lowers by 20% as compared the control value. Possible mechanisms of the effect of the yeast's mannans on the rat catalase are discussed.

Animals↗

[On the effect of immune and normal sera on catalase].

Effect of specific immune and normal sera on catalase was studied. The sera activated the enzyme, partially protected catalase against UV-irradiation and heating and also against the effect of inhibitors. Antibodies against catalase were observed in the fraction of 7 S gamma-globulins of immune serum. In studies of heat denaturation of catalase the stabilizing effect of immune serum was more distinct than the influence of normal serum and its protein fractions. In presence of serum protein fractions there was a correlation between the enthalpy of heat denaturation of catalase and decrease in specificity of the protein, in respect to the enxyme, associated with it in a complex. Alterations in enthropy compensated completely the decrease in enthalpy.

Animals↗

[Catalase and superoxide dismutase in the cells of strictly anaerobic microorganisms].

Strictly anaerobic microorganisms relating to various physiological groups were screened for catalase and superoxide dismutase (SOD) activity. All of the investigated anaerobes possessed the SOD activity, necessary for protection against toxic products of oxygen reduction. High specific activities of SOD were found in Acetobacterium woodii and Acetobacterium wieringae. Most of the investigated clostridia and acetogens were catalase-negative. A significant activity of catalase was found in Thermohydrogenium kirishiense, in representatives of the genus Desulfotomaculum, and in several methanogens. Methanobrevibacter arboriphilus had an exceptionally high catalase activity after growth in medium supplemented with hemin. Hemin also produced a strong positive effect on the catalase activity in many other anaerobic microorganisms. In methanogens, the activities of the enzymes of antioxidant defense varied in wide ranges depending on the stage of growth and the energy source.

Bacteria, Anaerobic↗

[Soil catalase activity of main plant communities in Leymus chinensis grassland in northeast China].

The seasonal dynamics of soil catalase activity of three different plants communities in Leymus chinensis grassland in northeast China were in a parabolas shape. The seasonal variation of Chloris virgata community was greater than those of Leymus chinensis community and Puccinellia tenuiflora community, and "seed effect" might be the main reason. The correlation between the activity of soil catalase in different soil layers and environmental factors were analyzed. The results showed that the activity of soil catalase was decreased gradually with depth of soil layer. The activity of soil catalase was closely correlated with rainfall and air temperature, and it was affected by soil temperature, soil moisture, and their interactions. The correlation between the activity and aboveground vegetation was very significant, and the growing condition of plant communities could be reflected by the activity of soil catalase.

Catalase↗

[Purification and properties of thermostable catalase in engineered E. coli].

A thermostable catalase in engineered bacterium E. coli was purified to electrophoretic homogenenity by heat treatment, ammonium sulfate fractionation precipitation, DEAE-A50 ion exchange chromatography, HiPrep 16/10 Phenyl hydrophobic interaction chromatography and Superdex200 HR 10/30 size exclusion chromatography with 187.2-fold purification and 9.8% recovery. The optimum reaction temperature and pH of this recombinant catalase were 70 degrees C and 7.0 respectively. The catalase is stable below 60 degrees C and at pH range 3-8. The residual activity of the catalase was about 60% after treated at 70 degrees C for 60 minutes and 80 degrees C for 10 minutes. The apprant Km and Vmax value of the catalase were 7.75 mmol/L and 27.8 mmol.min-1.mg-1 respectively. The affects of some metal ions and compounds on this enzyme were shown. Zn2+, Ba2+, Mn2+ of 1 mmol/L could completely inactivate the enzyme, EDTA of 50 mmol/L had no affect on activity.

Barium↗

[Construction of the non-resistant attenuated Salmonella typhimurium strain expressing Helicobacter pylori catalase].

OBJECTIVE: To construct a non-resistant attenuated Salmonella typhimurium (S.typhimurium) strain capable of expressing Helicobacter pylori (Hp) catalase. METHODS: After PCR amplification, the gene fragment encoding Hp catalase was inserted into the expression vector pYA248 containing asd gene, and the recombinant vector was then introduced into the host S.typhimurium strain X4072 depleted of genes encoding adenylate cyclase (delta cya), cyclic adenosine monophosphate receptor protein (delta crp) and aspartate-beta-semialdehyde dehydrogenase (delta asd). Bridged enzyme-linked immunosorbent assay (ELISA) was employed to measure the antigenicity of the catalase expressed in the sonicate and culture supernatant. According to Meacock's method and with the assistance of the growth curve, the stability of the recombinant strain was evaluated. A half lethal oral dose test was conducted to evaluate the safety of recombinant strain. RESULTS: S.typhimurium X4072 (pYA248-CAT) with expected capacity was successfully constructed, and bridged ELISA demonstrated higher catalase levels in the culture supernatant than in the sonicate of the recombinant strain X4072 (pYA248-CAT). After the strain was passaged for 100 generations without selection pressure, all the randomly selected colony of the recombinant strain grew well with positive catalase antigenicity as identified by ELISA. The growth curve of the recombinant strain showed comparable growth status of the 2 strains X4072 (pYA248) and X4072 (pYA248-CAT). The survival rate of C57BL/6 mice was 100% 30 d after oral administration of 1.0x10(10) cfu X4072 (pYA248-CAT). CONCLUSION: Non-resistant S. typhimurium vaccine X4072 (pYA248- CAT) is constructed successfully, which is stable in vitro and safe as confirmed by animal experiment. This vaccine provides a new candidate for viable oral vaccine against Hp infection.

Administration, Oral↗

[Influence of atrazine on the tyrosine environment of catalase].

By the UV difference spectrum and fluorescence spectrum technique, the influence of atrazine on tyrosine environment of catalase was studied. According to the results of the UV difference spectrum curve, the UV difference adsorption delta A260nm showed changing rapidly when pH ranging from 9.1 to 9.9. UV difference spectrum and fluorescence spectrum of atrazine-catalase were red shift that maybe caused by effect of hydrogen bonding. The fluorescence spectrum was sensitive to SDS and quenchable by KI. The results indicated that the tyrosine residues of catalase reside in hydrophilic core, and there is hydrogen bonding between atrazine and catalase probably. Atrazine has little effect on tyrosine environment of catalase.

Atrazine↗

Involvement of hydrogen peroxide in repression of catalase in TMV-infected resistant tobacco.

Catalases are ubiquitous, and play a role in plant defense against pathogens. We have reported that catalase mRNA and enzyme activity are repressed in the vicinity of hypersensitive tobacco lesions following TMV infection. We wished to identify the signals involved in this repression. Inoculation with TMV reduced catalase levels 26 to 28 h following infection, coincident with the known timing of endogenous salicylic acid (SA) accumulation. Application of SA caused a transient reduction in Ngcat1 mRNA level and catalase activity 4 to 6 h after treatment. However, repression was also observed in transgenic plants harboring the salicylate hydroxylase gene (NahG) and in TMV susceptible plants, which do not accumulate SA following TMV infection. In the same blots there was no induction of PR-1 or enhanced expression of H2O2-inducible glutathione-S-transferase and found that exposure to H2O2 also repressed Ngcat1 mRNA. Our findings suggest that repression of catalase transcription may be caused by the accumulation of H2O2 rather than of SA.

Catalase↗

[Activity of catalase after administration of some ADH and MEOS inhibitors: in vitro investigation in rat liver homogenates].

In the first pass methanol biotransformation three enzymatic systems: alcohol dehydrogenase (ADH), microsomal alcohol oxidising system (MEOS) linked with cytochrome P-450 and catalase are involved. Because of the toxicity of methanol, which is directly caused by its toxic metabolites, the major task in clinical toxicology is to inhibit each of these enzymes to protect human life. The aim of this investigation was to check the influence of some effective inhibitors of ADH and MEOS: 4-methylpyrazole, cimetidine, EDTA and 1,10-phenantroline on the activity of catalase with methanol as a substrate and the comparison with 3-amino-1,2,4-triasole. Catalase activity in rat hepatic homogenates was measured spectrophotometrically in vitro at physiological pH 7.4 and temp. 37 degrees C, assaying the degree of methanol oxidation according to Handler and Thurman. The quantity of arising formaldehyde was measured according with the method of Nash. Our results have shown that catalase activity was inhibited to different extents by all investigated compounds at concentrations of 10(-3) mol/l, 2 x 10(-4) mol/l, 10(-4) mol/l, 2 x 10(-5) mol/l, 10(-5) mol/l. 1,10-Phenantroline was found to be a highly effective inhibitor in comparison with aminotriasole. 4-Methylpyrazole, EDTA, 1,10-phenantroline and aminotriasole are catalase competitive inhibitors and cimetidine is non-competitive inhibitor. 4-Methylpyrazole has shown higher affinity to the enzyme than aminotriasole.

Alcohol Dehydrogenase↗

[Fibronectin upregulates catalase gene expression in rabbit bronchial epithelial cells].

We have previously shown that the binding of integrins with extracellular matrix component fibronectin (Fn) can improve the ability of bronchial epithelial cells (BECs) in resisting oxidant injury by up-regulating the activity of catalase and increasing the content of GSH. However, the molecular mechanism or its signaling pathway of this protection is still unclear. In order to examine the intracellular signaling mechanism activated by Fn-integrin binding reaction, the present study investigated the mRNA expression of catalase in primary cultured rabbit BECs using RT-PCR based on a cell-injury model made with ozone exposure. The product bands of target gene CAT were checked with Southern blot and oligonucleotide probe hybridization. The results showed that Fn (10 microg/ml) promoted the catalase mRNA transcription (P<0.01). This effect was abolished either by protein-tyrosine kinase inhibitor genistein or calmodulin inhibitor W(7) (P<0.01). These results indicate that the promotion of catalase activity induced by Fn-integrin reaction is partly due to the elevation of catalase mRNA transcription, and that its signalling are possibly relevant to tyrosine phosphorylation or calmodulin pathway.

Animals↗

Relationship between blood catalase activity and drinking history in a human population, a possible biological marker of the affinity to consume alcohol.

The relationship between blood catalase activity and alcohol consumption was investigated in a group of Caucasian volunteers (N = 191). Subjects individually attended a 1-hr session, during which they were asked to complete the Michigan Alcoholism Screening Test (MAST) and MacAndrew Scale (MAC), supply information on alcohol consumption (averaged over the most recent and typical 30-day periods: Recent and Typical Q-values) and other drug use by answering the Concordia Alcohol Screening Questionnaire (CASQ), and provide a 100-microliter blood sample from the fingertip. Results showed a significant positive relationship between typical Q-Value and catalase activity (r = 0.43, P less than 0.001), which improved after eliminating multiple drug users from the analysis (r = 0.65, P less than 0.001). Multiple regression analyses showed that catalase activity combined with being male, using cocaine or crack, scoring highly on the MAC scale and having alcohol-related problems (MAST), explained a significant portion of the variance in Typical Q-Value. These results support the notion that catalase activity is a strong positive determinant of alcohol intake and support the hypothesis that the enzyme catalase plays a role in regulating voluntary ethanol consumption.

Acetaldehyde↗

Lipid peroxidation and catalase in diabetes mellitus with and without ischemic stroke.

Production of reactive oxygen species (ROS) increased in diabetic patients and oxidative damage may contribute to the development of diabetic complications. Malondialdehyde is known as marker of the oxidative damage. Catalase is one of antioxidative factors involved in elimination of ROS In this study, the plasma level of lipid peroxides and plasma catalase activity in 315 patients with diabetes mellitus were assayed. We also included 114 non-diabetic healthy controls whose age, sex were matched to the diabetic patients. The plasma levels of lipid peroxides (LPO) were determined by spectrophotometric method modified by Satoh and Yagi. Lipid peroxidation was estimated by the plasma level of malondialdehyde (MDA). In controls mean value of plasma lipid peroxides was 1.329 +/- 0.118 nmol/ml. In diabetic patients with ischemic stroke MDA level was 2.919 +/- 0.182 nmol/l; p<0.001, and in patients without ischemic stroke the MDA level was 2.329 +/- 0.149 nmol/l; p<0.05; between diabetic patients with ischemic stroke and patients without ischemic stroke p<0.01. The high level of lipid peroxides might induce a self-maintained chronic process which, in time, might lead to the aggravation of the macro- and microangiopathy in diabetes. The plasma levels of catalase were determined by Goth's spectrophotometric method. In 114 healthy persons the mean value of plasma catalase (CAT) activity was 115.3 +/- 14.5 MU/l with less plasma catalase for females (108.7 +/- 12.4 MU/l) than for males (118.9 +/- 16.6 MU/l). Mean value of plasma CAT was (102.4 +/- 12.7 MU/l in patients with ischemic stroke, p<0.001 and 116.3 +/- 18.7 MU/l in patients without ischemic stroke, p<0.05); between diabetic patients with ischemic stroke and patients without ischemic stroke p<0.01. Our results revealed a decrease in plasma CAT activity in patients with diabetes mellitus and ischemic stroke as compared to patients with diabetes mellitus without ischemic stroke. We can conclude that in diabetic patients the decrease in plasma CAT activity is the consequence of oxidative modifications. These results suggest that diabetic patients have significantly increased oxidative damage.

Adult↗

[Oxidative stress and control of catalase activity in Escherichia coli].

Oxidative stress is a disbalanse between ROS generation and detoxification resulting in their increased level. It is commonly recognized that E. coli is the most suitable model system for the investigation of cell response to oxidative stress. E. coli is an enterobacteria which has specialized regulatory system for defence against ROS. Catalase is the key enzyme of the adaptive response. E. coli produces two forms of catalase--bifunctional catalase-peroxidase HPI and monofuctional catalase HPII. They are different in structure, kinetics, physico-chemical properties etc. HPI and HPII forms are members of various regulons which are regulated by different environmental factors. In this review we have summarized the present knowledge on two catalase forms and control of regulons responsible for antioxidant defence in E. coli.

Catalase↗

Precise method for the measurement of catalase activity in honey.

An improved method is reported for the determination of catalase activity in honey. We tested different dialysis membranes, dialysis fluid compositions and amounts, dialysis temperatures, sample amounts, and dialysis times. The best results were obtained by dialysis of 7.50 g sample in a cellulose dialysis sack, using two 3 L portions of 0.015 M sodium phosphate buffer (pH 7.0) as the dialysis fluid at 4 degrees C for 22 h. As in previous methods, catalase activity was determined on the basis of the rate of disappearance of the substrate, H202, with the H202 determined spectrophotometrically at 400 nm in an assay system containing o-dianisidine and peroxidase. Trials indicated that the best solvent for the o-dianisidine was 0.2 M sodium phosphate buffer, pH 6.1; the best starting H202 concentration was 3 mM; the best HCl concentration for stopping the reaction was 6 N; and the best sample volume for catalase measurement was 7.0 mL. Precision values (relative standard deviations for analyses of 10 subsamples of each of 3 samples) were high, ranging from 0.48% for samples with high catalase activity to 1.98% for samples with low catalase activity.

Buffers↗

[Catalase: structure, properties, functions].

Catalase (EC 1.11.1.6) is an enzyme which is present mainly in the peroxisomes of mammalian cells. It is a tetrameric enzyme consisting of four identical, tetrahedrally arranged subunits of 60 kDa, each containing in its active center a heme group and NADPH. Catalase has two enzymatic activities depending on the concentration of H2O2. If the concentration of H2O2 is high, catalase acts catalytically, i.e. removes H2O2 by forming H2O and O2 (catalatic reaction). However, at a low concentration of H2O2 and in the presence of a suitable hydrogen donor, e.g. ethanol, methanol, phenol, and others, catalase acts peroxidically, removing H2O2, but oxidizing its substrate (peroxidatic reaction). The review article presents current knowledge about the structure, properties, and functions of catalase in living organisms.

Animals↗