N-Acetyl-L-tryptophan or N-Acetyltryptophan, belongs to the class of organic compounds known as N-acyl-alpha amino acids. N-acyl-alpha amino acids are compounds containing an alpha amino acid which bears an acyl group at its terminal nitrogen atom. N-Acetyltryptophan can also be classified as an alpha amino acid or a derivatized alpha amino acid. Technically, N-Acetyltryptophan is a biologically available N-terminal capped form of the proteinogenic alpha amino acid L-tryptophan. N-acetyl amino acids can be produced either via direct synthesis of specific N-acetyltransferases or via the proteolytic degradation of N-acetylated proteins by specific hydrolases. N-terminal acetylation of proteins is a widespread and highly conserved process in eukaryotes that is involved in protection and stability of proteins. About 85% of all human proteins and 68% of all yeast proteins are acetylated at their N-terminus. Several proteins from prokaryotes and archaea are also modified by N-terminal acetylation. The majority of eukaryotic N-terminal-acetylation reactions occur through N-acetyltransferase enzymes or NAT. N-acetylated amino acids, such as N-acetyltryptophan can be released by an N-acylpeptide hydrolase from peptides generated by proteolytic degradation. In addition to the NAT enzymes and protein-based acetylation, N-acetylation of free tryptophan can also occur. Many N-acetylamino acids, including N-acetyltryptophan are classified as uremic toxins if present in high abundance in the serum or plasma. Uremic toxins are a diverse group of endogenously produced molecules that, if not properly cleared or eliminated by the kidneys, can cause kidney damage, cardiovascular disease and neurological deficits. Acetyltryptophan has been identified as a catabolite of tryptophan generated by the gut microbiota. After absorption through the intestinal epithelium, tryptophan catabolites enter the bloodstream and are later excreted in the urine.

Metabolism and Physiological Effects of N-Acetyltryptophan References