Aldehyde oxidase distribution

Li Calzi, Raviolo, C., Ghibaudi, E., De Gioia, Sahnona, M., Cazzaniga, G., Kurosaki, M., Terao, M., and Garattini, E., 1995, Purification, cDNA cloning and tissue distribution of bovine liver aldehyde oxidase, J. Biol. Chem. 270 31037931045. 

The enzymes are widely distributed in microorganisms, plants, and animals. " Three Mo-MPT enzymes have been found in mammals (1) xanthine dehydrogenase see Dehydrogenase) has many, varied roles in purine catabolism, drug metabolism, and oxidative stress response, (2) aldehyde oxidase is important in drug metabolism and the synthesis of retinoic acid from retinal, and (3) sulfite oxidase plays a cmcial role in the detoxification of sulfite produced in the degradation of cysteine and methionine. Genetic Mo-MPT deficiency in... 

Krenitsky, T.A. Tuttle, J.V. Cattan, E.L. and Wang, P. A comparison of the distribution and the electron acceptor specificities of xanthine oxidase and aldehyde oxidase. Comp Biochem Physiol 49B 687-703, 1974. 

There are probably more publications relating to xanthine oxidase than to any other enzyme studied, certainly more than those pertaining to aldehyde oxidase. This is presumably because the former enzyme is easily accessible from cow s milk rather than from animal tissue. It is not the purpose of this review to include all the data amassed on xanthine oxidase, as this has been fully covered in recent reviews [8, 12, 13]. Furthermore, most of our own work has been concerned with aldehyde oxidase. Thus, this report compares the properties of the molybdenum hydroxylases, where possible, in terms of distribution, substrate and inhibitor specificity and mechanism of oxidation. 

Table 3 2. COMPARATIVE DISTRIBUTION OF XANTHINE OXIDASE AND ALDEHYDE OXIDASE ACTIVITY IN MILK AND LIVER OF MAMMALIAN SPECIES [92, 93, 95]...

Aldehyde oxidase is structurally and chemically similar to xanthine oxidase, and both enzymes exhibit a similar distribution between tissues and share many common substrates, despite clear differences in certain catalytic properties. Thus, although both enzymes catalyze the oxidation of hypoxanthine to xanthine, conversion of the latter to uric acid is accomplished only by xanthine oxidase. 

Molybdenum is widely distributed in natural food. A normal adult male needs about 75-100 micro gram per day. It is normally accumulated in liver and kidneys whereas its concentration in other tissues is very low. Some flavo proteins like yanthinn oxidase and aldehyde oxidase contain traces of molybdenum in their prosthetic group. 

A comparison of xanthine oxidase and aldehyde oxidase was suggested by their functional and structural similarities. Both enzymes catalyze hydroxylation reactions in which water is the source of the hydroxyl group [6,7], both have particle weights around 300,000 [8,9], and both contain FAD, molybdenum, and iron in their internal electron transport chains [7,9]. This report summarizes the results of a comparison of the distributions, substrate specificities and electron acceptor specificities of these two enzymes [10,11] and discusses the possible implications of the findings. 

Aldehyde oxidase is not exclusively a mammalian enzyme. It was detected in many non-mammalian vertebrates and in the primitive invertebrate, the sea anemone (Sagart Ca luciae) [11]. Aldehyde oxidase, like xanthine oxidase, therefore, appears rather widely distributed in the animal kingdom. Such wide distribution suggests that the primary metabolic function of aldehyde oxidase is of a fundamental nature rather than a highly specialized one. 

Monoamine oxidases catalyze oxidative deamination of many primary, secondary, and tertiary amines. They have a wide tissue distribution including brain, liver, and intestine. A variety of endogenous amines, such as catecholamines, and pharmacological substances are metabolized. The products of primary amines are the corresponding aldehydes, ammonia, and hydrogen peroxide. 

Disposition in the Body. Rapidly metabolised before reaching the systemic circulation and therefore ineffective after oral administration poorly absorbed after subcutaneous injection widely distributed throughout the body. The principal metabolic reaction is 0-methylation catalysed by catechol-O-methyltrans-ferase to form normetanephrine this is followed by oxidative deamination catalysed by monoamine oxidase, to form 4-hydroxy-3-methoxymandelic aldehyde which is converted to 4-hydroxy-3-methoxymandelic acid (vanillylmandelic acid) and to... 

These enzymes (hydroxylases) are distributed across all phyla and include xanthine oxidoreductase (see Oxi-doreductase) (oxidase and dehydrogenase) aldehyde... 

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