1TA1

H141C mutant of rat liver arginase I

1TA1 の概要

• エントリーDOI: 10.2210/pdb1ta1/pdb
• 関連するPDBエントリー: 1RLA 1TBH 1TBJ 1TBL
• 分子名称: Arginase 1, MANGANESE (II) ION, GLYCEROL, ... (4 entities in total)
• 機能のキーワード: arginase, binuclear manganese cluster, h141c mutation, hydrolase
• 由来する生物種: Rattus norvegicus (Norway rat)
• 細胞内の位置: Cytoplasm: P07824
• タンパク質・核酸の鎖数: 3
• 化学式量合計: 102881.77

構造登録者

Cama, E.,Cox, J.D.,Ash, D.E.,Christianson, D.W. (登録日: 2004-05-19, 公開日: 2005-08-16, 最終更新日: 2024-02-14)

主引用文献

Colleluori, D.M.,Reczkowski, R.S.,Emig, F.A.,Cama, E.,Cox, J.D.,Scolnick, L.R.,Compher, K.,Jude, K.,Han, S.,Viola, R.E.,Christianson, D.W.,Ash, D.E.
Probing the role of the hyper-reactive histidine residue of arginase.
Arch.Biochem.Biophys., 444:15-26, 2005

PubMed Abstract: Rat liver arginase (arginase I) is potently inactivated by diethyl pyrocarbonate, with a second-order rate constant of 113M(-1)s(-1) for the inactivation process at pH 7.0, 25 degrees C. Partial protection from inactivation is provided by the product of the reaction, l-ornithine, while nearly complete protection is afforded by the inhibitor pair, l-ornithine and borate. The role of H141 has been probed by mutagenesis, chemical modulation, and X-ray diffraction. The hyper-reactivity of H141 towards diethyl pyrocarbonate can be explained by its proximity to E277. A proton shuttling role for H141 is supported by its conformational mobility observed among the known arginase structures. H141 is proposed to serve as an acid/base catalyst, deprotonating the metal-bridging water molecule to generate the metal-bridging hydroxide nucleophile, and by protonating the amino group of the product to facilitate its departure.

PubMed: 16266687
DOI: 10.1016/j.abb.2005.09.009

実験手法

X-RAY DIFFRACTION (2.5 Å)