Effect of Val 73 → Trp Mutation on the Reaction of “Cambialistic” Superoxide Dismutase fromPropionibacterium shermaniiwith Hydrogen Peroxide

1997 ◽  
Vol 345 (1) ◽  
pp. 156-159 ◽  
Author(s):  
R. Gabbianelli ◽  
A. Battistoni ◽  
C. Capo ◽  
F. Polticelli ◽  
G. Rotilio ◽  
...  
1997 ◽  
Vol 6 (5-6) ◽  
pp. 369-374
Author(s):  
Y. Oyanagui

Anti-inflammatory actions of two anti-allergic drugs, alone or with dexamethasone (Dex) were examined in two models, because inflammation is claimed to be important for allergic events, especially for asthma. Cromoglycate and nedocromil were tested in ischaemic- and histamineinduced paw oedema models of mice. These antiallergic drugs (1–100 mg/kg, i.p.) failed to suppress these oedemata, but enhanced the suppressions by a low dose of dexamethasone (0.1 mg/kg, s.c.) at 3–8 h after Dex injection. The mode of effects by anti-allergic drugs resembled that of a natural antioxidant (α-tocopherol, β-carotene etc.), and was different from that of an immunosuppressant like FK506. The enhancing potencies of the two anti-allergic drugs were similar at 6 h after Dex in both oedemata, and were diminished by superoxide dismutase (SOD) or catalase (i.p.). Cycloheximide completely abolished suppressions. Nedocromil, but not cromoglycate, inhibits inflammatory events. Therefore, there are common unknown actions by which the two anti-allergics enhance suppression by Dex. A possible mechanism of this action was supposed to enhance the superoxide and/or hydrogen peroxide-dependent glucocorticoid receptor (GR) signalling in the target cells.


1994 ◽  
Vol 40 (8) ◽  
pp. 630-636
Author(s):  
J. I. Pounder ◽  
A. J. Anderson

Survival of pseudomonads during plant colonization may involve bacterial catalases to degrade the hydrogen peroxide produced by the plant. The specific activities of catalases in lysates from two saprophytic isolates of Pseudomonas putida and Pseudomonas fluorescens and three races of Pseudomonas syringae pv. glycinea were similar. To explore the location of the bacterial catalases, cells of the pathogenic and saprophytic pseudomonads were treated with chloroform, which is reported to release periplasmic proteins. Although catalase was released by chloroform treatment, the cytoplasmic enzymes isocitrate dehydrogenase, superoxide dismutase, and glucose-6-phosphate dehydrogenase were also detected. These proteins may have come from lysis of a small proportion of the cells rather than the periplasm. Water treatment of cells also released amounts of protein similar to those derived from chloroform treatment. Similar responses were found from both pathogenic and saprophytic strains. The release of catalase and proteins from the leaf pathogen P. syringae pv. glycinea race 0 and the root-associated saprophyte P. putida decreased as the cultures aged. With P. putida and P. syringae pv. glycinea race 0, the single isozyme of catalase released by water and chloroform treatment also was detected in lysates. Additional catalase isozymes were present in lysates as the cultures aged.Key words: periplasmic proteins, survival.


1978 ◽  
Vol 176 (2) ◽  
pp. 351-358 ◽  
Author(s):  
P Lehtovaara

Leghaemoglobin from the root nodules of kidney bean (Phaseolus vulgaris) reacts in alkaline glycine solutions as a glycine oxidase in a reaction that may also be regarded as a coupled oxidation. Leghaemoglobin is reduced to the ferrous form by glycinate, the oxygen complex is formed, and finally the haem is attacked to yield a green reaction product. Glycine is simultaneously oxidized to glyoxylate, and hydrogen peroxide is generated. The initial velocity of the formation of the green product is proportional to the concentrations of leghaemoglobin and glycine, and the optimum pH for the reaction is 10.2. The green product is not formed if carbon monoxide, azide of imidazole is bound to the haem, whereas oxidation of glycine to glyoxylate is not inhibited by azide and not essentially by carbon monoxide. Haem breakdown is activated by digestion of leghaemoglobin by carboxypeptidase, and partly inhibited by catalase and superoxide dismutase.


Blood ◽  
1979 ◽  
Vol 53 (4) ◽  
pp. 666-676
Author(s):  
AI Tauber ◽  
TG Gabig ◽  
BM Babior

The particulate O-2-forming system from human neutrophils was found to oxidize methional and 2-keto-4-methylthiobutyric acid (KMB) to ethylene, indicating the formation by this system of strongly oxidizing radicals. Conforming this interpretation was the observation that ethylene production was inhibited by the radical scavengers benzoate, ethanol, and mannitol. Ethylene production was also sharply reduced by superoxide dismutase, implicatin O-2 as a precursor of oxidizing radicals. In our system catalase only partially inhibited ethylene generation from either methional or KMB, suggesting that oxidizing radicals are generated at least in part by the reacton of O-2 with compounds other than H2O2. We propose that in neutrophils oxidizing radicals are formed in a reaction between O-2 and a peroxide according to the following equation: O-2 + ROOH leads to RO . + OH- + O2, in which ROOH may be hydrogen peroxide, an alkyl peroxide, or an acyl peroxide (i.e., a peroxy acid).


Author(s):  
Aleksandra Vranic ◽  
Aleksandra Antovic ◽  
Nevena Draginic ◽  
Marijana Andjic ◽  
Marko Ravic ◽  
...  

Abstract The aim of this study was to assess oxidative status and to set baseline characteristics for female population with established rheumatoid arthritis. Total of 42 patients with rheumatoid arthritis and 48 age- and sex-matched controls were included in the study. Clinical examination was performed and assessed disease activity. Peripheral blood samples were used for all the assays. The markers of oxidative stress were assessed, including plasma levels of index of lipid peroxidation - thiobarbituric acid reactive substances, hydrogen peroxide, superoxide anion radical, nitrites and activity of superoxide dismutase, catalase and reduced glutathione levels as antioxidant parameters. In the patients group, levels of hydrogen peroxide and index of lipid peroxidation were higher than in controls. Patients with rheumatoid arthritis had decreased superoxide dismutase and catalase activity compared to healthy subjects. Interestingly, controls had higher levels of nitrites compared to patients. Patients showed a marked increase in reactive oxygen species formation and lipid peroxidation as well as decrease in the activity of antioxidant defense system leading to oxidative stress which may contribute to tissue and cartilage damage and hence to the chronicity of the disease.


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