1b1b | pdb_00001b1b
IRON DEPENDENT REGULATOR
Structural highlights
Function[IDER_MYCTU] Metal-dependent DNA-binding protein that controls transcription of many genes involved in iron metabolism. Acts as a repressor of siderophore biosynthesis and as a positive modulator of iron storage. Also regulates expression of transporters, proteins involved in siderophore synthesis, iron storage and transcriptional regulators.[1] [2] Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedIron-dependent regulators are a family of metal-activated DNA binding proteins found in several Gram-positive bacteria. These proteins are negative regulators of virulence factors and of proteins of bacterial iron-uptake systems. In this study we present the crystal structure of the iron-dependent regulator (IdeR) from Mycobacterium tuberculosis, the causative agent of tuberculosis. The protein crystallizes in the hexagonal space group P62 with unit cell dimensions a=b=92.6 A, c=63.2 A. The current model comprises the N-terminal DNA-binding domain (residues 1-73) and the dimerization domain (residues 74-140), while the third domain (residues 141-230) is too disordered to be included. The molecule lies on a crystallographic 2-fold axis that generates the functional dimer. The overall structure of the monomer shares many features with the homologous regulator, diphtheria toxin repressor (DtxR) from Corynebacterium diphtheriae. The IdeR structure in complex with Zinc reported here is, however, the first wild-type repressor structure with both metal binding sites fully occupied. This crystal structure reveals that both Met10 and most probably the Sgamma of Cys102 are ligands of the second metal binding site. In addition, there are important changes in the tertiary structure between apo-DtxR and holo-IdeR bringing the putative DNA binding helices closer together in the holo repressor. The mechanism by which metal binding may cause these structural changes between apo and holo wild-type repressor is discussed. Crystal structure of the iron-dependent regulator (IdeR) from Mycobacterium tuberculosis shows both metal binding sites fully occupied.,Pohl E, Holmes RK, Hol WG J Mol Biol. 1999 Jan 22;285(3):1145-56. PMID:9887269[3] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
| ||||||||||||||||||
