Alpha-ketoisovalerate

Alpha-ketoisovalerate (α-ketoisovalerate or α-KIV) is an organic compound and a keto acid. It is one of the intermediates of the Krebs cycle, which is the main metabolic pathway of aerobic respiration in cells.

Structure and Properties

Alpha-ketoisovalerate is a keto acid, which means it contains a carbonyl group (C=O) and a carboxyl group (-COOH). Its chemical formula is C5H8O3. It is a colorless, crystalline solid at room temperature.

Biological Role

In the metabolism of organisms, alpha-ketoisovalerate is an important intermediate. It is produced from leucine, an essential amino acid, through the process of transamination. The enzyme branched-chain amino acid transaminase catalyzes this reaction.

Alpha-ketoisovalerate can be further metabolized in several ways:

• It can be decarboxylated to produce isobutyryl-CoA, which is then further metabolized to produce acetyl-CoA, a key molecule in the Krebs cycle.
• It can be transaminated to produce valine, another essential amino acid.
• It can be reduced to produce isovaleryl-CoA, which is then further metabolized in the fatty acid synthesis pathway.

Clinical Significance

Abnormal levels of alpha-ketoisovalerate in the body can be indicative of certain medical conditions. For example, elevated levels can be a sign of maple syrup urine disease, a rare genetic disorder that affects the metabolism of certain amino acids.

See Also

• Keto acid
• Krebs cycle
• Leucine
• Valine
• Maple syrup urine disease