Triosephosphate isomerase is an extremely efficient metabolic enzyme that catalyzes the interconversion between dihydroxyacetone phosphate (DHAP) and D-glyceraldehyde-3-phosphate (G3P) in glycolysis and gluconeogenesis. It is also responsible for the non-negligible production of methylglyoxal a reactive cytotoxic side-product that modifies and can alter proteins, DNA and lipids. D-glyceraldehyde 3-phosphate = dihydroxyacetone phosphate dihydroxyacetone phosphate = methylglyoxal + phosphate Unstable only at extreme acidic (pH 1.0) or alkaline conditions (pH 11.0). IgE-binding activity is relatively stable under acidic and alkaline conditions, however the activity is increased between pH 2.0-3.0. Stable up to 100 degrees Celsius. IgE-binding activity is reduced with increasing temperature higher than 60 degrees Celsius. Carbohydrate biosynthesis; gluconeogenesis. Carbohydrate degradation; glycolysis; D-glyceraldehyde 3-phosphate from glycerone phosphate: step 1/1. Homodimer. Expressed in skeletal muscle (at protein level). Causes an allergic reaction in human. Binds weakly to IgE in 38% of the 13 patients tested allergic to crustaceans (crayfish and shrimp). Belongs to the triosephosphate isomerase family.