Triose Phosphate Isomerase

From Proteopedia

Revision as of 15:41, 21 March 2009

Template:STRUCTURE 1tim

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.

Structure & Function

Triose Phosphate Isomerase is a dimeric protein of two identical subunits. Each subunit contains 8 alpha helices surrounding 8 interior , which form the TIM barrels found in each respective subunit.

Disease

Triose Phosphate Isomerase Deficiency

TPI deficiency has been most closely linked to a point mutation at the Glu 104 residue which results in the GLU104Asp mutation

See Also

References

Triose Phosphate Isomerase [[1]]
Triose Phosphate Isomerase Deficiency [[2]]