1EUM

CRYSTAL STRUCTURE OF THE E.COLI FERRITIN ECFTNA

1EUM の概要

• エントリーDOI: 10.2210/pdb1eum/pdb
• 分子名称: FERRITIN 1 (2 entities in total)
• 機能のキーワード: e.coli non heme ferritin, ecftna, metal binding protein
• 由来する生物種: Escherichia coli
• 細胞内の位置: Cytoplasm: P0A998
• タンパク質・核酸の鎖数: 6
• 化学式量合計: 116656.57

構造登録者

Stillman, T.J.,Hempstead, P.D.,Artymiuk, P.J.,Andrews, S.C.,Hudson, A.J.,Treffry, A.,Guest, J.R.,Harrison, P.M. (登録日: 2000-04-17, 公開日: 2001-03-28, 最終更新日: 2024-02-07)

主引用文献

Stillman, T.J.,Hempstead, P.D.,Artymiuk, P.J.,Andrews, S.C.,Hudson, A.J.,Treffry, A.,Guest, J.R.,Harrison, P.M.
The high-resolution X-ray crystallographic structure of the ferritin (EcFtnA) of Escherichia coli; comparison with human H ferritin (HuHF) and the structures of the Fe(3+) and Zn(2+) derivatives.
J.Mol.Biol., 307:587-603, 2001

PubMed Abstract: The high-resolution structure of the non-haem ferritin from Escherichia coli (EcFtnA) is presented together with those of its Fe(3+) and Zn(2+) derivatives, this being the first high-resolution X-ray analysis of the iron centres in any ferritin. The binding of both metals is accompanied by small changes in the amino acid ligand positions. Mean Fe(A)(3+)-Fe(B)(3+) and Zn(A)(2+)-Zn(B)(2+) distances are 3.24 A and 3.43 A, respectively. In both derivatives, metal ions at sites A and B are bridged by a glutamate side-chain (Glu50) in a syn-syn conformation. The Fe(3+) derivative alone shows a third metal site (Fe( C)( 3+)) joined to Fe(B)(3+) by a long anti-anti bidentate bridge through Glu130 (mean Fe(B)(3+)-Fe(C)(3+) distance 5.79 A). The third metal site is unique to the non-haem bacterial ferritins. The dinuclear site lies at the inner end of a hydrophobic channel connecting it to the outside surface of the protein shell, which may provide access for dioxygen and possibly for metal ions shielded by water. Models representing the possible binding mode of dioxygen to the dinuclear Fe(3+) pair suggest that a gauche micro-1,2 mode may be preferred stereochemically. Like those of other ferritins, the 24 subunits of EcFtnA are folded as four-helix bundles that assemble into hollow shells and both metals bind at dinuclear centres in the middle of the bundles. The structural similarity of EcFtnA to the human H chain ferritin (HuHF) is remarkable (r.m.s. deviation of main-chain atoms 0.66 A) given the low amino acid sequence identity (22 %). Many of the conserved residues are clustered at the dinuclear centre but there is very little conservation of residues making inter-subunit interactions.

PubMed: 11254384
DOI: 10.1006/jmbi.2001.4475

実験手法

X-RAY DIFFRACTION (2.05 Å)