Near attack conformers dominate β-phosphoglucomutase complexes where geometry and charge distribution reflect those of substrate.

ABSTRACT: Experimental observations of fluoromagnesate and fluoroaluminate complexes of β-phosphoglucomutase (β-PGM) have demonstrated the importance of charge balance in transition-state stabilization for phosphoryl transfer enzymes. Here, direct observations of ground-state analog complexes of β-PGM involving trifluoroberyllate establish that when the geometry and charge distribution closely match those of the substrate, the distribution of conformers in solution and in the crystal predominantly places the reacting centers in van der Waals proximity. Importantly, two variants are found, both of which satisfy the criteria for near attack conformers. In one variant, the aspartate general base for the reaction is remote from the nucleophile. The nucleophile remains protonated and forms a nonproductiv

SUBMITTER: Griffin JL 

PROVIDER: S-EPMC3345020 | biostudies-literature | 2012 May

REPOSITORIES: biostudies-literature