Isomerization of dihydroxyacetone phosphate Triose phosphate isomerase interconverts dihydroxyacetone phos- phate and glyceraldehyde 3-phosphate (see Figure 8.16). Dihydro xy - acetone phosphate must be isomerized to glycer aldehyde 3-phosphate for further metabolism by the glycolytic pathway. This isomerization results in the net production of two molecules of glycer - aldehyde 3-phosphate from the cleavage products of fructose 1,6- bisphosphate.