Hydroxyacid oxidase 2

Hydroxyacid oxidase 2 (HAO2) is an enzyme that in humans is encoded by the HAO2 gene. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-OH group of donor with oxygen as acceptor. The systematic name of this enzyme class is hydroxyacid:oxygen 2-oxidoreductase. Other names in common use include glycolate oxidase, and hydroxyacid oxidase B.

Function

The HAO2 gene provides instructions for making an enzyme called hydroxyacid oxidase 2. This enzyme is found in peroxisomes, which are small sac-like compartments within cells. The hydroxyacid oxidase 2 enzyme is involved in the breakdown of amino acids, the building blocks of proteins. Specifically, it helps break down a particular amino acid called glycine.

Clinical significance

Mutations in the HAO2 gene have been associated with Primary hyperoxaluria, a rare condition characterized by the overproduction of a substance called oxalate (oxalic acid). In the kidneys, the excess oxalate combines with calcium to form calcium oxalate, a hard compound that is the main component of most kidney stones.

Structure

The HAO2 gene is located on the q arm of chromosome 9 (9q21.1). The gene spans approximately 23 kilobases and contains 6 exons. The encoded protein is a homodimeric protein that contains a FAD cofactor in each subunit.

See also

• Hydroxyacid oxidase
• Primary hyperoxaluria
• Oxidoreductase
• Peroxisome