9EJ2

Rat cytosolic PEPCK in complex with GTP and oxalate (293K)

9EJ2 の概要

• エントリーDOI: 10.2210/pdb9ej2/pdb
• 分子名称: Phosphoenolpyruvate carboxykinase, cytosolic [GTP], MANGANESE (II) ION, OXALATE ION, ... (6 entities in total)
• 機能のキーワード: inhibitor complex, metabolic enzyme, multi-temperature, ambient temperature, lyase
• 由来する生物種: Rattus norvegicus (Norway rat)
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 70425.85

構造登録者

McLeod, M.J.,Barwell, S.A.E.,Holyoak, T.,Thorne, R.E. (登録日: 2024-11-27, 公開日: 2025-04-09, 最終更新日: 2025-10-15)

主引用文献

McLeod, M.J.,Barwell, S.A.E.,Holyoak, T.,Thorne, R.E.
A structural perspective on the temperature dependent activity of enzymes.
Structure, 33:924-934.e2, 2025

PubMed Abstract: Enzyme activity varies with temperature. Unlike small-molecule catalysts, the structural ensembles of enzymes can change substantially with temperature, but it is unclear how this modulates temperature dependent activity. Here, multi-temperature X-ray crystallography was used to record structural changes from -20°C to 40°C for a mesophilic enzyme in complex with inhibitors mimicking substrate-, intermediate-, and product-bound states, representative of major complexes on the reaction coordinate. Inhibitors, substrates and active site loops increasingly populated catalytically competent conformations as temperature increased. These changes occurred even in temperature ranges where kinetic measurements showed roughly linear Arrhenius/Eyring behavior, where parameters characterizing the system are assumed to be temperature independent. Simple analysis shows that linear Arrhenius/Eyring behavior can still be observed when the underlying activation energy/enthalpy values vary with temperature. Our results indicate a critical role for temperature dependent atomic-resolution structural data in interpreting temperature dependent kinetic data from enzymatic systems.

PubMed: 40120576
DOI: 10.1016/j.str.2025.02.013

実験手法

X-RAY DIFFRACTION (2.12 Å)