4XW5

X-ray structure of PKAc with ATP, CP20, calcium ions

4XW5 の概要

• エントリーDOI: 10.2210/pdb4xw5/pdb
• 関連するPDBエントリー: 4XW4 4XW6
• 分子名称: cAMP-dependent protein kinase catalytic subunit alpha, cAMP-dependent protein kinase inhibitor alpha, CALCIUM ION, ... (5 entities in total)
• 機能のキーワード: protein kinase a, phosphorylation, catalytic subunit, reactant complex, transferase
• 由来する生物種: Mus musculus (Mouse); 詳細
• 細胞内の位置: Cytoplasm . Isoform 2: Cell projection, cilium, flagellum : P05132
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 44368.96

構造登録者

Gerlits, O.,Tian, J.,Das, A.,Taylor, S.,Langan, P.,Heller, T.W.,Kovalevsky, A. (登録日: 2015-01-28, 公開日: 2015-05-06, 最終更新日: 2024-10-23)

主引用文献

Gerlits, O.,Tian, J.,Das, A.,Langan, P.,Heller, W.T.,Kovalevsky, A.
Phosphoryl Transfer Reaction Snapshots in Crystals: INSIGHTS INTO THE MECHANISM OF PROTEIN KINASE A CATALYTIC SUBUNIT.
J.Biol.Chem., 290:15538-15548, 2015

PubMed Abstract: To study the catalytic mechanism of phosphorylation catalyzed by cAMP-dependent protein kinase (PKA) a structure of the enzyme-substrate complex representing the Michaelis complex is of specific interest as it can shed light on the structure of the transition state. However, all previous crystal structures of the Michaelis complex mimics of the PKA catalytic subunit (PKAc) were obtained with either peptide inhibitors or ATP analogs. Here we utilized Ca(2+) ions and sulfur in place of the nucleophilic oxygen in a 20-residue pseudo-substrate peptide (CP20) and ATP to produce a close mimic of the Michaelis complex. In the ternary reactant complex, the thiol group of Cys-21 of the peptide is facing Asp-166 and the sulfur atom is positioned for an in-line phosphoryl transfer. Replacement of Ca(2+) cations with Mg(2+) ions resulted in a complex with trapped products of ATP hydrolysis: phosphate ion and ADP. The present structural results in combination with the previously reported structures of the transition state mimic and phosphorylated product complexes complete the snapshots of the phosphoryl transfer reaction by PKAc, providing us with the most thorough picture of the catalytic mechanism to date.

PubMed: 25925954
DOI: 10.1074/jbc.M115.643213

実験手法

X-RAY DIFFRACTION (1.95 Å)