| ACT | |||||||
|---|---|---|---|---|---|---|---|
Crystal structure of E. coli aspartokinase iii in complex with aspartate and adp (r-state) | |||||||
| Identifiers | |||||||
| Symbol | ACT | ||||||
| Pfam | PF01842 | ||||||
| Pfam clan | CL0070 | ||||||
| InterPro | IPR002912 | ||||||
| SCOP2 | 1psd / SCOPe / SUPFAM | ||||||
| CDD | cd02116 | ||||||
| |||||||
In molecular biology, the ACT domain is a protein domain that is found in a variety of proteins involved in metabolism. ACT domains are linked to a wide range of metabolic enzymes that are regulated by amino acid concentration. The ACT domain is named after three of the proteins that contain it: aspartate kinase, chorismate mutase and TyrA. The archetypical ACT domain is the C-terminal regulatory domain of 3-phosphoglycerate dehydrogenase (3PGDH), which folds with a ferredoxin-like topology. A pair of ACT domains form an eight-stranded antiparallel sheet with two molecules of allosteric inhibitor serine bound in the interface. Biochemical exploration of a few other proteins containing ACT domains supports the suggestions that these domains contain the archetypical ACT structure.
The ACT domain was discovered by Aravind and Koonin using iterative sequence searches.