BIOCHEMISTRY A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z                    HOME ABOUT CATEGORIES SITE MAP COPYRIGHT ADVERTISE CONTACT entire Web this site tryptophan An essential amino acid. Tryptophan is also the largest amino acid. Its main function is as a building block in protein synthesis. Tryptophan is a precursor for serotonin (a neurotransmitter), melatonin (a neurohormone), and niacin. It is responsible for most of the absorbance of ultraviolet light (ca. 280 nm) by proteins. As a component of dietary protein, tryptophan is especially plentiful in chocolate, oats, bananas, dried dates, milk, cottage cheese, meat, fish, turkey, chicken, sesame, and peanuts. Related category    • BIOCHEMISTRY Also on this site: Encyclopedia of Alternative Energy & Sustainable Living Encyclopedia of History Transport Concepts & Designs (partner site) BACK TO TOP