| Type: | Domain | Name: | Biotin operon repressor, helix-turn-helix domain |
| Description: | The biotin operon of Escherichia colicontains 5 structural genes involved in the synthesis of biotin. Transcription of the operon is regulated via one of these proteins, BirA. BirA is an asymetric protein with 3 specific domains. The ligase reaction intermediate, biotinyl-5'-AMP, is the co-repressor that triggers DNA binding by BirA. The alpha-helical N-terminal domain of the BirA protein has the helix-turn-helix structure of DNA-binding proteins with a central DNA recognition helix. BirA undergoes several conformational changes related to repressor function and the N-terminal DNA-binding function is connected to the rest of the molecule through a hinge which will allow relocation of the domains during the reaction []. Two repressor molecules form the operator-repressor complex, with dimer formation occuring simultaneously with DNA binding. DNA-binding may cause a conformational change which allows this co-operative interaction. In the dimer structure, the beta-sheets in the central domain of each monomer are arranged side-by-side to form a single, seamless beta-sheet. | Short Name: | Biotin_operon_repress_HTH |
| DB identifier | Type | Name |
|---|---|---|
| IPR011991 | Domain | Winged helix-turn-helix DNA-binding domain |
| DB identifier | UniProt Accession | Secondary Identifier | Organism Name | Length |
|---|---|---|---|---|
| Brdisv1BdTR11A1044481m.p | PAC:35691595 | Brachypodium distachyon BdTR11a |
455
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