Aldehyde oxidase

An enzyme involved in the metabolism of aldehydes and nitrogen-containing compounds

Aldehyde oxidase

Aldehyde oxidase is a molybdenum-containing enzyme that plays a crucial role in the metabolism of aldehydes and nitrogen-containing compounds. It is involved in the oxidation of aldehydes to carboxylic acids and the hydroxylation of heterocycles. Aldehyde oxidase is found in the cytosol of cells and is particularly abundant in the liver.

Structure

Aldehyde oxidase is a homodimeric enzyme, meaning it consists of two identical subunits. Each subunit contains a molybdenum cofactor, two iron-sulfur clusters, and a flavin adenine dinucleotide (FAD) moiety. The molybdenum cofactor is essential for the enzyme's catalytic activity, facilitating the transfer of oxygen to the substrate.

Function

The primary function of aldehyde oxidase is to catalyze the oxidation of aldehydes to carboxylic acids. This reaction involves the transfer of electrons from the aldehyde to molecular oxygen, producing the corresponding carboxylic acid and hydrogen peroxide. Aldehyde oxidase also participates in the metabolism of various drugs and xenobiotics, contributing to their detoxification and elimination from the body.

Substrate Specificity

Aldehyde oxidase exhibits broad substrate specificity, acting on a wide range of aldehydes and nitrogen-containing heterocycles. It is known to oxidize aromatic and aliphatic aldehydes, as well as purines, pyrimidines, and pteridines. This broad substrate range makes aldehyde oxidase an important enzyme in drug metabolism, as it can influence the pharmacokinetics and pharmacodynamics of various therapeutic agents.

Clinical Significance

Aldehyde oxidase is involved in the metabolism of several clinically important drugs, including methotrexate, famciclovir, and ziprasidone. Variations in aldehyde oxidase activity can lead to differences in drug metabolism and response among individuals. Genetic polymorphisms in the aldehyde oxidase gene can result in altered enzyme activity, affecting drug efficacy and toxicity.

Related Enzymes

Aldehyde oxidase is part of the xanthine oxidase family of enzymes, which also includes xanthine dehydrogenase and xanthine oxidoreductase. These enzymes share structural similarities and catalytic mechanisms, but differ in their substrate specificities and physiological roles.

Gallery

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  Structure of aldehyde oxidase

Related pages

• Xanthine oxidase
• Drug metabolism
• Molybdenum cofactor
• Enzyme kinetics