Triosephosphate isomerase

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Triosephosphate isomerase 1

The structure of human TPI PDB 1WYI

Symbol(s): TPI1 TIM
Genetic data
Locus: Chr. 12 p13
Database Links
EC number: 5.3.1.1
Entrez: 7167
OMIM: 190450
RefSeq: NM_000365
UniProt: P60174


Triose-phosphate isomerase (TPI or TIM), is an enzyme (EC 5.3.1.1) that catalyzes the reversible interconversion of triose phosphates isomers dihydroxyacetone phosphate and D-glyceraldehyde 3-phosphate.

Dihydroxyacetone phosphate triose phosphate isomerase D-glyceraldehyde 3-phosphate
image:glycerone-phosphate_wpmp.png   image:D-glyceraldehyde-3-phosphate_wpmp.png
 
  triose phosphate isomerase

Compound C00111 at KEGG Pathway Database.Enzyme 5.3.1.1 at KEGG Pathway Database.Compound C00118 at KEGG Pathway Database.

Triose phosphate isomerase (TPI) plays an important role in glycolysis and is essential for efficient energy production. TPI has been found in every organism searched for the enzyme, including animals such as mammals and insects as well as in fungi, plants and bacteria.

In humans, deficiencies in TPI are associated with a progressive, severe neurological disorder called Triose Phosphate Isomerase deficiency.

Triose phosphate isomerase is a massively efficient enzyme, performing the reaction billions of times faster than it would naturally in solution. The reaction is so efficient it is limited by the rate the substrate can diffuse into the enzyme's active site.

Side view of triose phosphate isomerase.
Side view of triose phosphate isomerase.

[edit] Structure

Triose phosphate isomerase is a dimer of identical subunits, each of which is made up of about 250 amino acid residues. The three-dimensional structure of a subunit contains eight α-helices (blue and red) on the outside and eight parallel β-strands on the inside (violet and yellow). This structural motif is called an αβ-barrel, or a TIM-barrel, and is by far the most commonly observed protein fold. The active site of this enzyme is in the center of the barrel. A glutamic acid residue is involved in the catalytic mechanism. The sequence around the active site residue is conserved in all known triose phosphate isomerases.


[edit] See also

[edit] References

http://pdbdev.sdsc.edu:48346/pdb/molecules/pdb50_6.html

This metabolism related enzyme article is a stub. You can help Wikipedia by expanding it.
This article is of interest to the Metabolic Pathways WikiProject.


 v  d  e 
Glycolysis Metabolic Pathway
Glucose Glucose-6-phosphate Fructose 6-phosphate Fructose 1,6-bisphosphate Dihydroxyacetone phosphate Glyceraldehyde 3-phosphate Glyceraldehyde 3-phosphate
ATP ADP ATP ADP NAD+ + Pi NADH + H+
+ 2
NAD+ + Pi NADH + H+
1,3-Bisphosphoglycerate 3-Phosphoglycerate 2-Phosphoglycerate Phosphoenolpyruvate Pyruvate Acetyl-CoA
ADP ATP H2O ADP ATP CoA + NAD+ NADH + H+ + CO2
2 2 2 2 2 2
ADP ATP H2O
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