2PNC

Crystal Structure of Bovine Plasma Copper-Containing Amine Oxidase in Complex with Clonidine

2PNC の概要

• エントリーDOI: 10.2210/pdb2pnc/pdb
• 関連するPDBエントリー: 1KSI 1OAC 1TU5
• 関連するBIRD辞書のPRD_ID: PRD_900017
• 分子名称: Copper amine oxidase, liver isozyme, 2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose, COPPER (II) ION, ... (7 entities in total)
• 機能のキーワード: amine oxidase, oxidoreductase, quinoenzyme, tpq, clonidine
• 由来する生物種: Bos taurus (cattle)
• 細胞内の位置: Secreted, extracellular space: Q29437
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 168012.75

構造登録者

Cendron, L.,Holt, A.,Smith, D.J.,Zanotti, G.,Rigo, A.,Di Paolo, M.L. (登録日: 2007-04-24, 公開日: 2008-02-26, 最終更新日: 2023-08-30)

主引用文献

Holt, A.,Smith, D.J.,Cendron, L.,Zanotti, G.,Rigo, A.,Di Paolo, M.L.
Multiple binding sites for substrates and modulators of semicarbazide-sensitive amine oxidases: kinetic consequences
Mol.Pharmacol., 73:525-538, 2008

PubMed Abstract: Human semicarbazide-sensitive amine oxidase (SSAO) is a target for novel anti-inflammatory drugs that inhibit enzymatic activity. However, progress in developing such drugs has been hampered by an incomplete understanding of mechanisms involved in substrate turnover. We report here results of a comparative study of human and bovine SSAO enzymes that reveal binding of substrates and other ligands to at least two (human) and up to four (bovine) distinct sites on enzyme monomers. Anaerobic spectroscopy reveals binding of substrates (spermidine and benzylamine) and of an imidazoline site ligand (clonidine) to the reduced active site of bovine SSAO, whereas interactions with oxidized enzyme are evident in kinetic assays and crystallization studies. Radioligand binding experiments with [(3)H]tetraphenylphosphonium, an inhibitor of bovine SSAO that binds to an anionic cavity outside the active site, reveal competition with spermidine, benzylamine, and clonidine, indicating that these ligands also bind to this second anionic region. Kinetic models of bovine SSAO are consistent with one spermidine molecule straddling the active and secondary sites on both oxidized and reduced enzyme, whereas these sites are occupied by two individual molecules of smaller substrates such as benzylamine. Clonidine and other imidazoline site ligands enhance or inhibit activity as a result of differing affinities for both sites on oxidized and reduced enzyme. In contrast, although analyses of kinetic data obtained with human SSAO are also consistent with ligands binding to oxidized and reduced enzyme, we observed no apparent requirement for substrate or modulator binding to any secondary site to model enzyme behavior.

PubMed: 17989349
DOI: 10.1124/mol.107.040964

実験手法

X-RAY DIFFRACTION (2.4 Å)