1-Aminocyclopropanecarboxylic acid

1-Aminocyclopropanecarboxylic acid (ACC) is a biochemical compound that is a significant intermediate in the biosynthesis of the plant hormone ethylene. It is synthesized from methionine by the enzyme ACC synthase (ACS) and converted to ethylene by ACC oxidase (ACO).

Structure and Properties

1-Aminocyclopropanecarboxylic acid is a cyclic compound with a three-membered ring. It contains an amino group (-NH2) and a carboxylic acid group (-COOH), making it an amino acid, although it is not one of the 20 proteinogenic amino acids.

Biosynthesis

The biosynthesis of 1-aminocyclopropanecarboxylic acid begins with the amino acid methionine, which is converted to S-adenosylmethionine (SAM) by the enzyme SAM synthetase. SAM is then converted to ACC by the enzyme ACC synthase, in a reaction that also produces 5'-methylthioadenosine (MTA).

Role in Ethylene Biosynthesis

1-Aminocyclopropanecarboxylic acid is a key intermediate in the biosynthesis of the plant hormone ethylene. It is converted to ethylene by the enzyme ACC oxidase, in a reaction that requires oxygen and produces carbon dioxide and cyanide. The cyanide is then detoxified by the enzyme beta-cyanoalanine synthase.

Applications

1-Aminocyclopropanecarboxylic acid has been used in plant physiology research to study the role of ethylene in plant growth and development. It has also been used in agriculture to promote fruit ripening and to control plant growth.

See Also

• Ethylene
• ACC synthase
• ACC oxidase
• Methionine
• S-adenosylmethionine