6NEE

Crystal structure of a reconstructed ancestor of Triosephosphate isomerase from eukaryotes

6NEE の概要

• エントリーDOI: 10.2210/pdb6nee/pdb
• 分子名称: TRIOSEPHOSPHATE ISOMERASE, PHOSPHOGLYCOLOHYDROXAMIC ACID (3 entities in total)
• 機能のキーワード: isomerase, glycolisis, tim barrel, ancestral sequence reconstruction
• 由来する生物種: synthetic construct
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 55419.46

構造登録者

Rodriguez-Romero, A.,Schulte-Sasse, M.,Fernandez-Velasco, D.A. (登録日: 2018-12-17, 公開日: 2019-01-09, 最終更新日: 2023-10-11)

主引用文献

Schulte-Sasse, M.,Pardo-Avila, F.,Pulido-Mayoral, N.O.,Vazquez-Lobo, A.,Costas, M.,Garcia-Hernandez, E.,Rodriguez-Romero, A.,Fernandez-Velasco, D.A.
Structural, thermodynamic and catalytic characterization of an ancestral triosephosphate isomerase reveal early evolutionary coupling between monomer association and function.
FEBS J., 286:882-900, 2019

PubMed Abstract: Function, structure, and stability are strongly coupled in obligated oligomers, such as triosephosphate isomerase (TIM). However, little is known about how this coupling evolved. To address this question, five ancestral TIMs (ancTIMs) in the opisthokont lineage were inferred. The encoded proteins were purified and characterized, and spectroscopic and hydrodynamic analysis indicated that all are folded dimers. The catalytic efficiency of ancTIMs is very high and all dissociate into inactive and partially unfolded monomers. The placement of catalytic residues in the three-dimensional structure, as well as the enthalpy-driven binding signature of the oldest ancestor (TIM63) resemble extant TIMs. Although TIM63 dimers dissociate more readily than do extant TIMs, calorimetric data show that the free ancestral subunits are folded to a greater extent than their extant counterparts are, suggesting that full catalytic proficiency was established in the dimer before the stability of the isolated monomer eroded. Notably, the low association energy in ancTIMs is compensated for by a high activation barrier, and by a significant shift in the dimer-monomer equilibrium induced by ligand binding. Our results indicate that before the animal and fungi lineages diverged, TIM was an obligated oligomer with substrate binding properties and catalytic efficiency that resemble that of extant TIMs. Therefore, TIM function and association have been strongly coupled at least for the last third of biological evolution on earth. DATABASES: PDB Entry: 6NEE. ENZYMES: Triosephosphate isomerase 5.3.1.1, Glycerol-3-phosphate dehydrogenase 1.1.1.8.

PubMed: 30589511
DOI: 10.1111/febs.14741

実験手法

X-RAY DIFFRACTION (1.9 Å)