Threonine dehydratase, ACT-like domain (IPR001721)

Short name: TD_ACT-like

Overlapping homologous superfamilies

Domain relationships



Threonine deaminase (threonine dehydratase, TD) is the first enzyme on the pathway for the biosynthesis of isoleucine. TD is organized into two domains. The larger N-terminal domain is considered the catalytic domain as it contains the essential pyridoxal phosphate cofactor. The C-terminal regulatory domain folds as an eight-stranded antiparallel sheet. The holoenzyme is a homotetramer in which the intersubunit contacts lie between pairs of C-terminal regulatory domains and pairs of N-terminal domains [PMID: 9562556].

The ACT domain is a 90 amino acid long domain, which has been named after three of the allosterically regulated enzymes in which it is found: aspartate kinase, chorismate mutase and TyrA (prephenate dehydrogenase) [PMID: 10222208]. The ACT domain is found in a variety of contexts and is proposed to be a structurally conserved regulatory domain involved in the binding of small ligands, such as amino acids. There is a close structural and functional relationship between the regulatory domain of TD and the ACT domain [PMID: 11751050].

Contributing signatures

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