Triosephosphate isomerase 1 (TPI1)

Triosephosphate isomerase 1 (TPI1) is a highly conserved, homodimeric enzyme essential for glycolysis, catalyzing the reversible interconversion of dihydroxyacetone phosphate and glyceraldehyde 3-phosphate without cofactors. It is structurally characterized by the TIM barrel fold and displays “catalytic perfection,” limited only by substrate diffusion rates. TPI1 is expressed in almost all eukaryotes and many prokaryotes, with additional non-canonical functions being investigated, such as nuclear signaling relationships and contributions to cancer biology. Deficiency or malfunction due to genetic mutations causes severe, early-onset anemia, neuromuscular and metabolic dysfunction, reflecting its indispensability for cellular energy production. While not a current direct drug target, the enzyme’s central role in metabolism and implications for disease make it an area of active research.

Other names

Triosephosphate isomeraseTPITIMTriose-phosphate isomeraseMethylglyoxal synthaseHEL-S-49TPIDepididymis secretory protein Li 49

Chemical inhibitors bind at the active site, competing with substrate or mimicking transition states, thus blocking isomerase activity