2HJI

Structural model for the Fe-containing isoform of acireductone dioxygenase

2HJI の概要

• エントリーDOI: 10.2210/pdb2hji/pdb
• 関連するPDBエントリー: 1VR3 1ZRR
• NMR情報: BMRB: 7103
• 分子名称: E-2/E-2' protein, FE (II) ION (3 entities in total)
• 機能のキーワード: dioxygenase, non-heme iron, isozyme, methionine salvage, structural entropy, oxidoreductase
• 由来する生物種: Klebsiella oxytoca
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 20275.26

構造登録者

Pochapsky, T.C.,Ju, T.,Maroney, M.J.,Chai, S.C. (登録日: 2006-06-30, 公開日: 2006-10-24, 最終更新日: 2024-05-29)

主引用文献

Ju, T.,Goldsmith, R.B.,Chai, S.C.,Maroney, M.J.,Pochapsky, S.S.,Pochapsky, T.C.
One Protein, Two Enzymes Revisited: A Structural Entropy Switch Interconverts the Two Isoforms of Acireductone Dioxygenase
J.Mol.Biol., 363:823-834, 2006

PubMed Abstract: Acireductone dioxygenase (ARD) catalyzes different reactions between O2 and 1,2-dihydroxy-3-oxo-5-(methylthio)pent-1-ene (acireductone) depending upon the metal bound in the active site. Ni2+ -ARD cleaves acireductone to formate, CO and methylthiopropionate. If Fe2+ is bound (ARD'), the same substrates yield methylthioketobutyrate and formate. The two forms differ in structure, and are chromatographically separable. Paramagnetism of Fe2+ renders the active site of ARD' inaccessible to standard NMR methods. The structure of ARD' has been determined using Fe2+ binding parameters determined by X-ray absorption spectroscopy and NMR restraints from H98S ARD, a metal-free diamagnetic protein that is isostructural with ARD'. ARD' retains the beta-sandwich fold of ARD, but a structural entropy switch increases order at one end of a two-helix system that bisects the beta-sandwich and decreases order at the other upon interconversion of ARD and ARD', causing loss of the C-terminal helix in ARD' and rearrangements of residues involved in substrate orientation in the active site.

PubMed: 16989860
DOI: 10.1016/j.jmb.2006.08.060

実験手法

SOLUTION NMR