Triose Phosphate Isomerase
From Proteopedia
Triose Phosphate Isomerase is a dimeric protein of two identical subunits. Each subunit contains surrounding 8 interior
Overview
(TPI or TIM) which catalyzes the reversible interconversion of the triose phosphate isomers dihydroxyacetone phosphate and D-glyceraldehyde-3-phosphate, an essential process in the glycolytic pathway.
Mechanism
TPI catalyzes the transfer of a hydrogen atom from carbon 1 to carbon 2, an intramolecular oxidation-reduction. This isomerization of a ketose to an aldose proceeds through an enediol intermediate.<Biochemistry 6th Edition>
Acid Base Catalysis
TPI carries out the isomerization reaction through acid base chemistry involving
These two catalytic residues include which plays the role of the general base catalyst in a proton abstraction mechanism as it abstracts a proton from carbon 1, which then donates it to carbon 2. Glutamate 165 requires , the general acid which donates a proton to the C-1 carbonyl oxygen.
Diagram .[1]
Proteopedia Page Contributors and Editors (what is this?)
Gregg Snider, Eric Martz, Michal Harel, Alexander Berchansky, David Canner, Eran Hodis, Stephen Everse, Angel Herraez, Jane S. Richardson
