What is the Origin of D-Amino Acids?

The nomenclature derives from the concept of stereochemistry, specifically the D- and L- configurations, which denote the absolute spatial arrangement of the atoms around the central alpha-carbon. The designation comes from the Latin dexter (right) for D and laevus (left) for L, based on their relation to glyceraldehyde. The realization that living systems contain both forms, not just the L-form, expanded the understanding of biological complexity beyond traditional protein synthesis.

What is the Mechanism of D-Amino Acids?

The mechanism of action for D-Amino Acids is distinct from their L-counterparts, often involving specialized enzymes for their synthesis and degradation, such as D-amino acid oxidase. In the brain, D-serine acts as a critical co-agonist at the NMDA receptor, a key player in synaptic plasticity and learning, illustrating a direct role in neurotransmission. In the gut, D-Amino Acids are predominantly products of bacterial metabolism, influencing the microbiome and potentially acting as signaling molecules that interface with the host's endocrine and immune systems.

D-Amino Acids

Meaning

D-Amino Acids are chiral mirror-image isomers of the more common L-Amino Acids, which are the primary building blocks of proteins in mammals. While L-Amino Acids are typically found in protein structures, D-Amino Acids exist naturally in the body, primarily in the brain, nervous tissue, and microbial cell walls. They are considered non-proteinogenic in the human context, but their presence suggests distinct physiological and regulatory roles, particularly as signaling molecules and components of neuromodulation. Research is uncovering their significance in various processes, including aging, neurodegenerative disorders, and gut health.