In the splitting stage of glycolysis, Fru-1,6-BP is cleaved in the middle by a reverse-aldol reaction (Fig. 11.3, bottom), thus the name aldolase. The aldolase reaction is a freely reversible equilibrium reaction, yielding two triose-phosphates, dihydroxyacetone phosphate and glyceraldehyde-3-phosphate, from the top and bottom half of the molecule, respectively. Only the glyceraldehyde-3-phosphate continues through the yield stage of glycolysis, but triose phosphate isomerase catalyzes the interconversion of dihydroxyacetone phosphate into glyceraldehyde 3-phosphate, so that both halves of the glucose molecule are metabolized to lactate.
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