6F3M

Crystal structure of S-adenosyl-L-homocysteine hydrolase from Pseudomonas aeruginosa complexed with adenosine, K+ and Zn2+ cations

6F3M の概要

• エントリーDOI: 10.2210/pdb6f3m/pdb
• 分子名称: Adenosylhomocysteinase, NICOTINAMIDE-ADENINE-DINUCLEOTIDE, ADENOSINE, ... (9 entities in total)
• 機能のキーワード: regulation of sam-dependent methylation reactions, hydrolase
• 由来する生物種: Pseudomonas aeruginosa (strain ATCC 15692 / DSM 22644 / CIP 104116 / JCM 14847 / LMG 12228 / 1C / PRS 101 / PAO1); 詳細
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 207320.94

構造登録者

Czyrko, J.,Brzezinski, K. (登録日: 2017-11-28, 公開日: 2018-08-08, 最終更新日: 2024-01-17)

主引用文献

Czyrko, J.,Sliwiak, J.,Imiolczyk, B.,Gdaniec, Z.,Jaskolski, M.,Brzezinski, K.
Metal-cation regulation of enzyme dynamics is a key factor influencing the activity of S-adenosyl-L-homocysteine hydrolase from Pseudomonas aeruginosa.
Sci Rep, 8:11334-11334, 2018

PubMed Abstract: S-adenosyl-L-homocysteine hydrolase from Pseudomonas aeruginosa (PaSAHase) coordinates one K ion and one Zn ion in the substrate binding area. The cations affect the enzymatic activity and substrate binding but the molecular mechanisms of their action are unknown. Enzymatic and isothermal titration calorimetry studies demonstrated that the K ions stimulate the highest activity and strongest ligand binding in comparison to other alkali cations, while the Zn ions inhibit the enzyme activity. PaSAHase was crystallized in the presence of adenine nucleosides and K or Rb ions. The crystal structures show that the alkali ion is coordinated in close proximity of the purine ring and a Na NMR study showed that the monovalent cation coordination site is formed upon ligand binding. The cation, bound in the area of a molecular hinge, orders and accurately positions the amide group of Q65 residue to allow its interaction with the ligand. Moreover, binding of potassium is required to enable unique dynamic properties of the enzyme that ensure its maximum catalytic activity. The Zn ion is bound in the area of a molecular gate that regulates access to the active site. Zn coordination switches the gate to a shut state and arrests the enzyme in its closed, inactive conformation.

PubMed: 30054521
DOI: 10.1038/s41598-018-29535-y

実験手法

X-RAY DIFFRACTION (1.6 Å)