Triose Phosphate Isomerase: Difference between revisions
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TPI catalyzes the transfer of a hydrogen atom from carbon 1 to carbon 2, an intramolecular oxidation-reduction reaction.[[Image:TPI 2D mechanism2.png|right|thumb|400px| '''Isomerization reaction catalyzed by TPI''']] This isomerization of a ketose to an aldose proceeds through an ''cis''-enediol(ate) intermediate. This isomerization proceeds without any cofactors and the enzyme confers a 10<sup>9</sup> rate enhancement relative to the nonenzymatic reaction involving a chemical base (acetate ion).<ref>PMID:2043623</ref>. | TPI catalyzes the transfer of a hydrogen atom from carbon 1 to carbon 2, an intramolecular oxidation-reduction reaction.[[Image:TPI 2D mechanism2.png|right|thumb|400px| '''Isomerization reaction catalyzed by TPI''']] This isomerization of a ketose to an aldose proceeds through an ''cis''-enediol(ate) intermediate. This isomerization proceeds without any cofactors and the enzyme confers a 10<sup>9</sup> rate enhancement relative to the nonenzymatic reaction involving a chemical base (acetate ion).<ref>PMID:2043623</ref>. | ||
[[Image:TPIkinetics.png|thumb|400px| '''Kinetic constants of Triose Phosphate Isomerase''']] | [[Image:TPIkinetics.png|thumb|400px| '''Kinetic constants of Triose Phosphate Isomerase''']] | ||
<StructureSection load='2ypi' size='500' side='right' scene=Triose_Phosphate_Isomerase/Three_catalytic_residues/6/> | |||
=== Acid-Base Catalysis === | === Acid-Base Catalysis === | ||
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[[Image:crisscross2.png|right|thumb|750x350px| ''' Alternative "Criss-Cross" TPI Mechanism Involving LBHB Between Glu165 and O1 of the Intermediate''']] | [[Image:crisscross2.png|right|thumb|750x350px| ''' Alternative "Criss-Cross" TPI Mechanism Involving LBHB Between Glu165 and O1 of the Intermediate''']] | ||
.</StructureSection> | |||