1fx7 | pdb_00001fx7
CRYSTAL STRUCTURE OF THE IRON-DEPENDENT REGULATOR (IDER) FROM MYCOBACTERIUM TUBERCULOSIS
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 primary transcriptional regulators of virulence factors and iron scavenging systems that are important for infection by several bacterial pathogens. Here we present the 2.0-A crystal structure of the wild type iron-dependent regulator from Mycobacterium tuberculosis in its fully active holorepressor conformation. Clear, unbiased electron density for the Src homology domain 3-like third domain, which is often invisible in structures of iron-dependent regulators, was revealed by density modification and averaging. This domain is one of the rare examples of Src homology domain 3-like folds in bacterial proteins, and, in addition, displays a metal binding function by contributing two ligands, one Glu and one Gln, to the pentacoordinated cobalt atom at metal site 1. Both metal sites are fully occupied, and tightly bound water molecules at metal site 1 ("Water 1") and metal site 2 ("Water 2") are identified unambiguously. The main chain carbonyl of Leu4 makes an indirect interaction with the cobalt atom at metal site 2 via Water 2, and the adjacent residue, Val5, forms a rare gamma turn. Residues 1-3 are well ordered and make numerous interactions. These ordered solvent molecules and the conformation and interactions of the N-terminal pentapeptide thus might be important in metal-dependent activation. Crystal structure of the iron-dependent regulator from Mycobacterium tuberculosis at 2.0-A resolution reveals the Src homology domain 3-like fold and metal binding function of the third domain.,Feese MD, Ingason BP, Goranson-Siekierke J, Holmes RK, Hol WG J Biol Chem. 2001 Feb 23;276(8):5959-66. Epub 2000 Oct 26. PMID:11053439[3] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
| ||||||||||||||||||||
