Enzyme Architecture: Self-Assembly of Enzyme and Substrate Pieces of Glycerol-3-Phosphate Dehydrogenase into a Robust Catalyst of Hydride Transfer.

ABSTRACT: The stabilization of the transition state for hlGPDH-catalyzed reduction of DHAP due to the action of the phosphodianion of DHAP and the cationic side chain of R269 is between 12.4 and 17 kcal/mol. The R269A mutation of glycerol-3-phosphate dehydrogenase (hlGPDH) results in a 9.1 kcal/mol destabilization of the transition state for enzyme-catalyzed reduction of dihydroxyacetone phosphate (DHAP) by NADH, and there is a 6.7 kcal/mol stabilization of this transition state by 1.0 M guanidine cation (Gua⁺) [J. Am. Chem. Soc. 2015, 137, 5312-5315]. The R269A mutant shows no detectable activity toward reduction of glycolaldehyde (GA), or activation of this reaction by 30 mM HPO₃^2-. We report the unprecedented self-assembly of R269A hlGPDH, dianions (X^2-

SUBMITTER: Reyes AC 

PROVIDER: S-EPMC5291162 | biostudies-literature | 2016 Nov

REPOSITORIES: biostudies-literature