MARINE BORER ALDEHYDE OXIDASE

1965 ◽  
Vol 43 (6) ◽  
pp. 1011-1019 ◽  
Author(s):  
P. M. Townsley ◽  
R. A. Richy
Keyword(s):  
Methylene Blue ◽  
Cytochrome C ◽  
Xanthine Oxidase ◽  
Digestive Tract ◽  
Vanillic Acid ◽  
Oxidase Activity ◽  
Aldehyde Oxidase ◽  
The Other ◽  
Specific Enzyme ◽  
Simultaneous Reduction

A very active and specific enzyme, aldehyde oxidase, has been demonstrated and partially purified from the digestive tract of the marine borer, Bankia setacea (Tryon). In the presence of the enzyme, the substrate vanillin was oxidized to vanillic acid with the simultaneous reduction of oxygen, cytochrome c, 2,6-dichlorophenolindophenol, or methylene blue. Marine borer aldehyde oxidase does not oxidize the heterocyclic substrates N1-methylnicotinamide or hypoxanthine of mammalian hepatic aldehyde oxidase or milk xanthine oxidase. In addition, the inhibitors of hepatic aldehyde oxidase, menadione and estradiol, do not inhibit marine borer aldehyde oxidase. On the other hand, both the above-mentioned oxidases are inhibited by the sulfhydryl inhibitors arsenite and p-hydroxymercurybenzoate, and by cyanide. Marine borer aldehyde oxidase has an optimum activity between pH 4.5 and 5.5 and little activity at pH 7.8, a pH activity range quite different from that of the mammalian aldehyde oxidases. Oysters were found to contain only slight vanillin oxidase activity at pH 4.3, suggesting that the marine borer aldehyde oxidase activity is unique to the ship worm and is used for the oxidation of aldehydes found in wood.

scholarly journals Xanthine Oxidase of the Clothes Moth, Tineola Bisselliella, and Some Other Insects

1955 ◽  
Vol 8 (3) ◽  
pp. 369 ◽  
Author(s):  
H Irzykiewicz
Keyword(s):  
Methylene Blue ◽  
Uric Acid ◽  
Toxic Effect ◽  
Xanthine Oxidase ◽  
Oxidase Activity ◽  
Acid Production ◽  
Fat Body ◽  
Optimum Concentration ◽  
Optimum Ph ◽  
Wet Weight

Xanthine oxidase activity in Tineola larvae averages 200� /!moles of uric acid per g whole larva (wet weight) per hr and in Tenebrio, Lucilia, Anthrenocerus, Ephestia, and Anthrenus larvae activity ranges between 13�4 and 1�3. The optimum pH for Tineola xanthine oxidase lies between pH 7�7 and 8� 0, and the optimum concentration of xanthine is at or below 1�3 X 10-3M. Methylene blue in concentrations up to 5�3 X 1O-3M has no toxic effect on this enzyme, and the lower concentrations of methylene blue have a limiting effect. Cyanide and 6-pteridyl aldehyde inhibit Tineola xanthine oxidase. The insect xanthine oxidases are demonstrated to be dehydrogenases. DPN, and pyruvate and DPN together, stimulate uric acid production by Tineola xanthine oxidase in the absence of methylene blue. In Tenebrio larvae there is a higher concentration of xanthine oxidase in the midgut and fat-body than in the remaining tissues.

Cytochrome c, an ideal antioxidant

2003 ◽  
Vol 31 (6) ◽  
pp. 1312-1315 ◽  
Author(s):  
M.O. Pereverzev ◽  
T.V. Vygodina ◽  
A.A. Konstantinov ◽  
V.P. Skulachev
Keyword(s):  
Superoxide Dismutase ◽  
Membrane Potential ◽  
Cytochrome C ◽  
Xanthine Oxidase ◽  
Cytochrome Oxidase ◽  
The Other ◽  
Other Hand ◽  
O2 Reduction

Generation of Δψ (membrane potential) by cytochrome oxidase proteoliposomes oxidizing superoxide-reduced cytochrome c has been demonstrated. XO+HX (xanthine oxidase and hypoxanthine) were used to produce superoxide. It was found that the generation of Δψ is completely abolished by cyanide (an uncoupler) or by superoxide dismutase, and is enhanced by nigericin. Addition of ascorbate after XO+HX causes a further increase in Δψ. On the other hand, XO+HX added after ascorbate do not affect Δψ, indicating that superoxide does not have measurable protonophorous activity. The half-maximal cytochrome c concentration for Δψ generation supported by XO+HX was found to be approx. 1 μM. These data and the results of some other researchers can be rationalized as follows: (1) O2 accepts an electron to form superoxide; (2) cytochrome c oxidizes superoxide back to O2; (3) an electron removed from the reduced cytochrome c is transferred to O2 by cytochrome oxidase in a manner that generates ΔμH+ (transmembrane difference in electrochemical H+ potential). Thus cytochrome c mediates a process of superoxide removal, resulting in regeneration of O2 and utilization of the electron involved previously in the O2 reduction. It is important that cytochrome c is not damaged during the antioxidant reaction, in contrast with many other antioxidants.

scholarly journals The influence of porphyrins on iron-catalysed generation of hydroxyl radicals

1988 ◽  
Vol 250 (1) ◽  
pp. 197-201 ◽  
Author(s):  
J Van Steveninck ◽  
J P J Boegheim ◽  
T M A R Dubbelman ◽  
J Van der Zee
Keyword(s):  
Cytochrome C ◽  
Horseradish Peroxidase ◽  
Experimental Evidence ◽  
Xanthine Oxidase ◽  
Hydroxyl Radicals ◽  
Anion Radical ◽  
The Other ◽  
Haematoporphyrin Derivative ◽  
Other Hand

Uroporphyrin I, haematoporphyrin and haematoporphyrin derivative had no effect on O2-. generation during oxidation of hypoxanthine by xanthine oxidase and on the formation of hydroxyl radicals (OH.) in the hypoxanthine/xanthine oxidase/Fe3+-EDTA/deoxyribose system. On the other hand, these porphyrins strongly inhibited O2-. formation in a horseradish peroxidase/H2O2/NADPH mixture, whereas they augmented OH. generation in this system after addition of Fe3+-EDTA. Experimental evidence suggests that these observations should be ascribed to the formation of a porphyrin anion radical in the horseradish peroxidase/NADPH system. The formation of this anion radical was confirmed by e.s.r. spectroscopy. This radical is apparently unable to reduce cytochrome c, but it can replace O2-. in the OH.-generating Haber-Weiss reaction.

scholarly journals The action of cyanide and other respiratory inhibitors on xanthine oxidase

1936 ◽  
Vol 119 (813) ◽  
pp. 159-190 ◽  
Keyword(s):  
Methylene Blue ◽  
Xanthine Oxidase ◽  
The Other ◽  
Respiratory Inhibitors ◽  
Cyanide Inhibition

It was stated by Dixon and Thurlow (1925) that xanthine oxidase is not inhibited by cyanide. They found that concentrations of cyanide up to M/100 did not produce any inhibition of either the uptake of oxygen or the reduction of methylene blue by hypoxanthine in presence of the enzyme. Some inhibition was, however, observed with higher concentrations of cyanide. During the course of some other work on xanthine oxidase, Dixon and Lemberg, using the methylene blue technique, observed in 1931 (unpublished) that even small concentrations of cyanide completely inactivated the oxidase, provided that it was incubated with the cyanide for some time at 37° before testing. Similar results were later obtained by Keilin (unpublished) for O 2 uptake. A reinvestigation of the action of cyanide on the xanthine oxidase was therefore desirable, and the results obtained are described in the present paper. It has been found that the action of cyanide on this oxidase shows a number of peculiar features which distinguish it from the other cases of cyanide inhibition hitherto known.

Ultrastructural localization of xanthine oxidase activity in the digestive tract of the rat

1995 ◽  
Vol 27 (11) ◽  
pp. 897-905 ◽  
Author(s):  
Rosier J. M. Van Den Munckhof ◽  
Helena Vreeling-Sindelárová ◽  
Jacques P. M. Schellens ◽  
Cornelis J. F. Van Noorden ◽  
Wilma M. Frederiks
Keyword(s):  
Xanthine Oxidase ◽  
Digestive Tract ◽  
Oxidase Activity ◽  
Ultrastructural Localization ◽  
Xanthine Oxidase Activity

GENETIC CONTROL OF ALDEHYDE OXIDASE ACTIVITY AND CROSS-REACTING-MATERIAL IN DROSOPHILA MELANOGASTER

1978 ◽  
Vol 20 (4) ◽  
pp. 489-497 ◽  
Author(s):  
Eva M. Meidinger ◽  
John H. Williamson
Keyword(s):  
Drosophila Melanogaster ◽  
Genetic Control ◽  
Structural Gene ◽  
Oxidase Activity ◽  
Aldehyde Oxidase ◽  
Xanthine Dehydrogenase ◽  
The Other ◽  
Pyridoxal Oxidase

Four different genes are known to affect aldehyde oxidase activity (AO) in Drosophila melanogaster. Mutants at each of these loci eliminate AO activity and simultaneously eliminate detectable AO-crossing reacting material (AO-CRM) even though only one is the structural gene for AO (Aldoxn). The other three genes (cin1, lxd and mal) coordinately "control" the levels of activity of AO and two related enzymes, xanthine dehydrogenase (XDH) and pyridoxal oxidase (PO). Contrary to their effects on AO-CRM, neither of these three mutants eliminate XDH-CRM. A model of interaction of these enzymes and genes controlling their activities is discussed.

scholarly journals Kinetics and specificity of guinea pig liver aldehyde oxidase and bovine milk xanthine oxidase towards substituted benzaldehydes.

2004 ◽  
Vol 51 (3) ◽  
pp. 649-663 ◽  
Author(s):  
Georgios I Panoutsopoulos ◽  
Christine Beedham
Keyword(s):  
Guinea Pig ◽  
Xanthine Oxidase ◽  
Oxidase Activity ◽  
Bovine Milk ◽  
Aromatic Aldehydes ◽  
Aldehyde Oxidase ◽  
Inhibitory Effect ◽  
Pig Liver ◽  
Alkyl Benzenes ◽  
Guinea Pig Liver

Molybdenum-containing enzymes, aldehyde oxidase and xanthine oxidase, are important in the oxidation of N-heterocyclic xenobiotics. However, the role of these enzymes in the oxidation of drug-derived aldehydes has not been established. The present investigation describes the interaction of eleven structurally related benzaldehydes with guinea pig liver aldehyde oxidase and bovine milk xanthine oxidase, since they have similar substrate specificity to human molybdenum hydroxylases. The compounds under test included mono-hydroxy and mono-methoxy benzaldehydes as well as 3,4-dihydroxy-, 3-hydroxy-4-methoxy-, 4-hydroxy-3-methoxy-, and 3,4-dimethoxy-benzaldehydes. In addition, various amines and catechols were tested with the molybdenum hydroxylases as inhibitors of benzaldehyde oxidation. The kinetic constants have shown that hydroxy-, and methoxy-benzaldehydes are excellent substrates for aldehyde oxidase (Km values 5x10(-6) M to 1x10(-5) M) with lower affinities for xanthine oxidase (Km values around 10(-4) M). Therefore, aldehyde oxidase activity may be a significant factor in the oxidation of the aromatic aldehydes generated from amines and alkyl benzenes during drug metabolism. Compounds with a 3-methoxy group showed relatively high Vmax values with aldehyde oxidase, whereas the presence of a 3-hydroxy group resulted in minimal Vmax values or no reaction. In addition, amines acted as weak inhibitors, whereas catechols had a more pronounced inhibitory effect on the aldehyde oxidase activity. It is therefore possible that aldehyde oxidase may be critical in the oxidation of the analogous phenylacetaldehydes derived from dopamine and noradrenaline.

Superoxide, Xanthine Oxidase and Platelet Reactions: Further Studies on Mechanisms by which Oxidants Influence Platelets

1981 ◽  
Vol 45 (03) ◽  
pp. 290-293 ◽  
Author(s):  
Peter H Levine ◽  
Danielle G Sladdin ◽  
Norman I Krinsky
Keyword(s):  
Superoxide Dismutase ◽  
Cytochrome C ◽  
Xanthine Oxidase ◽  
Direct Effect ◽  
Platelet Function ◽  
Experimental Conditions ◽  
Release Reaction

SummaryIn the course of studying the effects on platelets of the oxidant species superoxide (O- 2), Of was generated by the interaction of xanthine oxidase plus xanthine. Surprisingly, gel-filtered platelets, when exposed to xanthine oxidase in the absence of xanthine substrate, were found to generate superoxide (O- 2), as determined by the reduction of added cytochrome c and by the inhibition of this reduction in the presence of superoxide dismutase.In addition to generating Of, the xanthine oxidase-treated platelets display both aggregation and evidence of the release reaction. This xanthine oxidase induced aggreagtion is not inhibited by the addition of either superoxide dismutase or cytochrome c, suggesting that it is due to either a further metabolite of O- 2, or that O- 2 itself exerts no important direct effect on platelet function under these experimental conditions. The ability of Of to modulate platelet reactions in vivo or in vitro remains in doubt, and xanthine oxidase is an unsuitable source of O- 2 in platelet studies because of its own effects on platelets.

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