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Structural, thermodynamic and catalytic characterization of an ancestral triosephosphate isomerase reveal early evolutionary coupling between monomer association and function
Author(s) -
SchulteSasse Mariana,
PardoÁvila Fátima,
PulidoMayoral Nancy O.,
VázquezLobo Alejandra,
Costas Miguel,
GarcíaHernández Enrique,
RodríguezRomero Adela,
FernándezVelasco Daniel Alejandro
Publication year - 2019
Publication title -
the febs journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.981
H-Index - 204
eISSN - 1742-4658
pISSN - 1742-464X
DOI - 10.1111/febs.14741
Subject(s) - triosephosphate isomerase , dimer , monomer , crystallography , oligomer , ligand (biochemistry) , extant taxon , function (biology) , protein data bank (rcsb pdb) , chemistry , biology , stereochemistry , enzyme , biochemistry , evolutionary biology , receptor , organic chemistry , polymer
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 TIM s (anc TIM s) 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 anc TIM s 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 ( TIM 63) resemble extant TIM s. Although TIM 63 dimers dissociate more readily than do extant TIM s, 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 anc TIM s 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 TIM s. 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 .