Rozovsky S and McDermott AE (2007) Substrate product equilibrium on a reversible enzyme, triosephosphate isomerase. Proc Natl Acad Sci U S A 104(7):2080-5
Abstract: The highly efficient glycolytic enzyme, triosephosphate isomerase, is expected to differentially stabilize the proposed stable reaction species: ketone, aldehyde, and enediol(ate). The identity and steady-state populations of the chemical entities bound to triosephosphate isomerase have been probed by using solid- and solution-state NMR. The 13C-enriched ketone substrate, dihydroxyacetone phosphate, was bound to the enzyme and characterized at steady state over a range of sample conditions. The ketone substrate was observed to be the major species over a temperature range from -60 degrees C to 15 degrees C. Thus, there is no suggestion that the enzyme preferentially stabilizes the reactive intermediate or the product. The predominance of dihydroxyacetone phosphate on the enzyme would support a mechanism in which the initial proton abstraction in the reaction from dihydroxyacetone phosphate to D-glyceraldehyde 3-phosphate is significantly slower than the subsequent chemical steps.
|Status: Published||Type: Journal Article | Research Support, N.I.H., Extramural||PubMed ID: 17287353|
Topics addressed in this paper
- To go to the Locus page for a gene, click on the gene name.
|Protein Physical Properties|