1BI3

STRUCTURE OF APO-AND HOLO-DIPHTHERIA TOXIN REPRESSOR

1BI3 の概要

• エントリーDOI: 10.2210/pdb1bi3/pdb
• 分子名称: DIPHTHERIA TOXIN REPRESSOR, ZINC ION, SULFATE ION, ... (4 entities in total)
• 機能のキーワード: repressor, transcription regulation, dna-binding, iron
• 由来する生物種: Corynebacterium diphtheriae
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 51086.66

構造登録者

Pohl, E.,Hol, W.G.J. (登録日: 1998-06-21, 公開日: 1999-06-22, 最終更新日: 2024-10-23)

主引用文献

Pohl, E.,Holmes, R.K.,Hol, W.G.
Motion of the DNA-binding domain with respect to the core of the diphtheria toxin repressor (DtxR) revealed in the crystal structures of apo- and holo-DtxR.
J.Biol.Chem., 273:22420-22427, 1998

PubMed Abstract: The diphtheria toxin repressor (DtxR) from Corynebacterium diphtheriae is a divalent metal-activated repressor of chromosomal genes that encode proteins responsible for siderophore-mediated iron uptake and also of the gene of certain corynebacteriophages that encodes diphtheria toxin. DtxR consists of two 25.3-kDa three-domain subunits and is a member of a family of related repressor proteins in several Gram-positive bacterial species, some of which are important human pathogens. In this paper, we report on the first high resolution crystal structures of apo-DtxR in two related space groups. In addition, crystal structures of Zn-DtxR were determined in the same two space groups. The resolutions of the structures range from 2.2 to 2.4 A. The four refined models of the apo- and the holo-repressor exhibit quite similar metal binding centers, which do, however, show higher thermal motion in the apo-structures. All four structures reported differ from each other in one important aspect. The N-terminal DNA-binding domain and the last 20 residues of the dimerization domain of each subunit move significantly with respect to the core of the DtxR dimer, which consists of residues 74-120 from both subunits. These results provide the first indication of a conformational change that may occur upon binding of the holo-repressor to DNA.

PubMed: 9712865
DOI: 10.1074/jbc.273.35.22420

実験手法

X-RAY DIFFRACTION (2.4 Å)