 Whereas the α-aminoadipate (AAA) pathway is part of the glutamate biosynthetic family.The DAP pathway is found in both prokaryotes and plants and begins with the dihydrodipicolinate synthase (DHDPS) (E.C 4.3.3.7) catalysed condensation reaction between the aspartate derived, "L"-aspartate semialdehyde, and pyruvate to form (4"S")-4-hydroxy-2,3,4,5-tetrahydro-(2"S")-dipicolinic acid (HTPA).The product is then reduced by dihydrodipicolinate reductase (DHDPR) (E.C 1.3.1.26), with NAD(P)H as a proton donor, to yield 2,3,4,5-tetrahydrodipicolinate (THDP).