[1] The aspartate pathway is an amino acid metabolic pathway present in bacteria and plants that deal with converting aspartate to other amino acids through a series of reactions and intermediates.

This reversible chemical reaction is shown below:[3] Once dihydrodipicolinate is synthesized, it can continue down the metabolic pathway leading to the synthesis of lysine.

[4] Other than the lysine biosynthetic pathway, L-aspartate-4-semialdehyde can also undergo a reversible reaction catalyzed by the enzyme homoserine dehydrogenase.

This reaction, which turns L-aspartate-4-semialdehyde into homoserine is shown below:[5] Homoserine represents another branch in the aspartate pathway, as it can progress down one of two pathways to eventually become one of two amino acids: threonine or methionine.

This aspartate pathway is present in plants and bacteria, allowing them to synthesize lysine, methionine, and threonine.