Amidohydrolase (IPR017439)

Short name: Amidohydrolase

Overlapping homologous superfamilies

Family relationships


This entry represents a clade of the amidohydrolases. They classified as metallopeptidases belonging to MEROPS peptidase family M20 (clan MH), subfamily M20D. Included within this group are hydrolases of hippurate (N-benzylglycine), indoleacetic acid (IAA) N-conjugates of amino acids, N-acetyl-L-amino acids and aminobenzoylglutamate. These hydrolases are of the carboxypeptidase-type, most likely utilizing a zinc ion in the active site.

In higher plants, the growth hormone indole-3-acetic acid (IAA or auxin) is stored conjugated to sugar moieties via an ester linkage or to amino acids or peptides via an amide. More than 95% of the hormone in a plant can be found in the conjugated form, leaving only a small amount of free hormone available to stimulate and control cellular growth. The overall levels of active IAA in a plant can be controlled not only by the amount of IAA synthesized, but also by the quantity of IAA that is released from the conjugated state into the free state. Amidohydrolases cleave the amide bond between the auxin and the conjugated amino acid. Several IAA amidohydrolases have been isolated from Arabidopsis thaliana (Mouse-ear cress), each of these enzymes has different substrate specificities. The A. thaliana IAA amidohydrolase, IAR3, is able to cleave IAA-Alanine, while products of the other amidohydrolase genes, known as the ILR1-like family of hydrolases (ILR1, ILL1, ILL2, ILL3, and ILL5), cleave primarily IAA-Phenylalanine and IAA-Leucine [PMID: 7792599].

GO terms

Biological Process

No terms assigned in this category.

Molecular Function

GO:0016787 hydrolase activity

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.