3RET

Salicylate and Pyruvate Bound Structure of the Isochorismate-Pyruvate Lyase K42E Mutant from Pseudomonas aerugionsa

3RET の概要

• エントリーDOI: 10.2210/pdb3ret/pdb
• 関連するPDBエントリー: 3REM
• 分子名称: Salicylate biosynthesis protein pchB, 2-HYDROXYBENZOIC ACID, PYRUVIC ACID, ... (4 entities in total)
• 機能のキーワード: intertwined dimer, lyase, mutase
• 由来する生物種: Pseudomonas aeruginosa
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 23346.36

構造登録者

Olucha, J.,Ouellette, A.N.,Luo, Q.,Lamb, A.L. (登録日: 2011-04-05, 公開日: 2011-07-27, 最終更新日: 2023-11-15)

主引用文献

Olucha, J.,Ouellette, A.N.,Luo, Q.,Lamb, A.L.
pH Dependence of Catalysis by Pseudomonas aeruginosa Isochorismate-Pyruvate Lyase: Implications for Transition State Stabilization and the Role of Lysine 42.
Biochemistry, 50:7198-7207, 2011

PubMed Abstract: An isochorismate-pyruvate lyase with adventitious chorismate mutase activity from Pseudomonas aerugionsa (PchB) achieves catalysis of both pericyclic reactions in part by the stabilization of reactive conformations and in part by electrostatic transition-state stabilization. When the active site loop Lys42 is mutated to histidine, the enzyme develops a pH dependence corresponding to a loss of catalytic power upon deprotonation of the histidine. Structural data indicate that the change is not due to changes in active site architecture, but due to the difference in charge at this key site. With loss of the positive charge on the K42H side chain at high pH, the enzyme retains lyase activity at ∼100-fold lowered catalytic efficiency but loses detectable mutase activity. We propose that both substrate organization and electrostatic transition state stabilization contribute to catalysis. However, the dominant reaction path for catalysis is dependent on reaction conditions, which influence the electrostatic properties of the enzyme active site amino acid side chains.

PubMed: 21751784
DOI: 10.1021/bi200599j

実験手法

X-RAY DIFFRACTION (1.79 Å)