2W22

Activation Mechanism of Bacterial Thermoalkalophilic Lipases

2W22 の概要

• エントリーDOI: 10.2210/pdb2w22/pdb
• 分子名称: TRIACYLGLYCEROL LIPASE, CALCIUM ION, ZINC ION, ... (6 entities in total)
• 機能のキーワード: thermoalkalophilic lipases, hydrolase, open conformation, activation mechanism
• 由来する生物種: GEOBACILLUS THERMOCATENULATUS
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 45034.00

構造登録者

Carrasco-Lopez, C.,Godoy, C.,De Las Rivas, B.,Fernandez-Lorente, G.,Palomo, J.M.,Guisan, J.M.,Fernandez-Lafuente, R.,Hermoso, J.A. (登録日: 2008-10-23, 公開日: 2008-12-16, 最終更新日: 2023-12-13)

主引用文献

Carrasco-Lopez, C.,Godoy, C.,de Las Rivas, B.,Fernandez-Lorente, G.,Palomo, J.M.,Guisan, J.M.,Fernandez-Lafuente, R.,Martinez-Ripoll, M.,Hermoso, J.A.
Activation of bacterial thermoalkalophilic lipases is spurred by dramatic structural rearrangements.
J. Biol. Chem., 284:4365-4372, 2009

PubMed Abstract: The bacterial thermoalkalophilic lipases that hydrolyze saturated fatty acids at 60-75 degrees C and pH 8-10 are grouped as the lipase family I.5. We report here the crystal structure of the lipase from Geobacillus thermocatenulatus, the first structure of a member of the lipase family I.5 showing an open configuration. Unexpectedly, enzyme activation involves large structural rearrangements of around 70 amino acids and the concerted movement of two lids, the alpha6- and alpha7-helices, unmasking the active site. Central in the restructuring process of the lids are both the transfer of bulky hydrophobic residues out of the N-terminal end of the alpha6-helix and the incorporation of short side chain residues to the alpha6 C-terminal end. All these structural changes are stabilized by the Zn(2+)-binding domain, which is characteristic of this family of lipases. Two detergent molecules are placed in the active site, mimicking chains of the triglyceride substrate, demonstrating the position of the oxyanion hole and the three pockets that accommodate the sn-1, sn-2, and sn-3 fatty acids chains. The combination of structural and biochemical studies indicate that the lid opening is not mediated by temperature but triggered by interaction with lipid substrate.

PubMed: 19056729
DOI: 10.1074/jbc.M808268200

実験手法

X-RAY DIFFRACTION (2.2 Å)