4H6S

Crystal structure of thrombin mutant E14eA/D14lA/E18A/S195A

4H6S の概要

• エントリーDOI: 10.2210/pdb4h6s/pdb
• 関連するPDBエントリー: 1SHH 4H6T
• 分子名称: Prothrombin, SODIUM ION, ... (4 entities in total)
• 機能のキーワード: serine protease, prethrombin-2, autoactivation, hydrolase, hydrolase-peptide complex, hydrolase/peptide
• 由来する生物種: Homo sapiens (human); 詳細
• 細胞内の位置: Secreted, extracellular space: P00734 P00734
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 33274.20

構造登録者

Pozzi, N.,Chen, Z.,Zapata, F.,Pelc, L.A.,Di Cera, E. (登録日: 2012-09-19, 公開日: 2013-03-13, 最終更新日: 2024-11-27)

主引用文献

Pozzi, N.,Chen, Z.,Zapata, F.,Niu, W.,Barranco-Medina, S.,Pelc, L.A.,Di Cera, E.
Autoactivation of thrombin precursors.
J.Biol.Chem., 288:11601-11610, 2013

PubMed Abstract: Trypsin-like proteases are synthesized as inactive zymogens and convert to the mature form upon activation by specific enzymes, often assisted by cofactors. Central to this paradigm is that the zymogen does not convert spontaneously to the mature enzyme, which in turn does not feed back to activate its zymogen form. In the blood, the zymogens prothrombin and prethrombin-2 require the prothrombinase complex to be converted to the mature protease thrombin, which is unable to activate prothrombin or prethrombin-2. Here, we show that replacement of key residues within the activation domain causes these zymogens to spontaneously convert to thrombin. The conversion is started by the zymogen itself, which is capable of binding ligands at the active site, and is abrogated by inactivation of the catalytic residue Ser-195. The product of autoactivation is functionally and structurally equivalent to wild-type thrombin. Zymogen autoactivation is explained by conformational selection, a basic property of the trypsin fold uncovered by structural and rapid kinetics studies. Both the zymogen and protease undergo a pre-existing equilibrium between active and inactive forms. The equilibrium regulates catalytic activity in the protease and has the potential to unleash activity in the zymogen to produce autoactivation. A new strategy emerges for the facile production of enzymes through zymogen autoactivation that is broadly applicable to trypsin-like proteases of biotechnological and clinical interest.

PubMed: 23467412
DOI: 10.1074/jbc.M113.451542

実験手法

X-RAY DIFFRACTION (2.19 Å)