5F19

The Crystal Structure of Aspirin Acetylated Human Cyclooxygenase-2

5F19 の概要

• エントリーDOI: 10.2210/pdb5f19/pdb
• 関連するPDBエントリー: 5F1A
• 分子名称: Prostaglandin G/H synthase 2, alpha-D-mannopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose, 2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose, ... (9 entities in total)
• 機能のキーワード: membrane protein, cyclooxygenase, cyxlooxygenase-2, monotopic, aspirin, complex, covalent inhibitor, oxidoreductase-inhibitor complex, oxidoreductase/inhibitor
• 由来する生物種: Homo sapiens (Human)
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 132205.01

構造登録者

Lucido, M.J.,Orlando, B.J.,Malkowski, M.G. (登録日: 2015-11-30, 公開日: 2016-03-16, 最終更新日: 2024-11-20)

主引用文献

Lucido, M.J.,Orlando, B.J.,Vecchio, A.J.,Malkowski, M.G.
Crystal Structure of Aspirin-Acetylated Human Cyclooxygenase-2: Insight into the Formation of Products with Reversed Stereochemistry.
Biochemistry, 55:1226-1238, 2016

PubMed Abstract: Aspirin and other nonsteroidal anti-inflammatory drugs target the cyclooxygenase enzymes (COX-1 and COX-2) to block the formation of prostaglandins. Aspirin is unique in that it covalently modifies each enzyme by acetylating Ser-530 within the cyclooxygenase active site. Acetylation of COX-1 leads to complete loss of activity, while acetylation of COX-2 results in the generation of the monooxygenated product 15(R)-hydroxyeicosatetraenoic acid (15R-HETE). Ser-530 has also been shown to influence the stereochemistry for the addition of oxygen to the prostaglandin product. We determined the crystal structures of S530T murine (mu) COX-2, aspirin-acetylated human (hu) COX-2, and huCOX-2 in complex with salicylate to 1.9, 2.0, and 2.4 Å, respectively. The structures reveal that (1) the acetylated Ser-530 completely blocks access to the hydrophobic groove, (2) the observed binding pose of salicylate is reflective of the enzyme-inhibitor complex prior to acetylation, and (3) the observed Thr-530 rotamer in the S530T muCOX-2 crystal structure does not impede access to the hydrophobic groove. On the basis of these structural observations, along with functional analysis of the S530T/G533V double mutant, we propose a working hypothesis for the generation of 15R-HETE by aspirin-acetylated COX-2. We also observe differential acetylation of COX-2 purified in various detergent systems and nanodiscs, indicating that detergent and lipid binding within the membrane-binding domain of the enzyme alters the rate of the acetylation reaction in vitro.

PubMed: 26859324
DOI: 10.1021/acs.biochem.5b01378

実験手法

X-RAY DIFFRACTION (2.04 Å)