- 2-Amino-3-(3-indolyl)propionic acid; the l-isomer is a component of proteins; a nutritionally essential amino acid.- t. 2,3-dioxygenase an oxidoreductase catalyzing the reaction of l-t. and O2 to produce l-N-formylkynurenine; an adaptive enzyme, the level (in the liver) being controlled by adrenal hormones; a step in t. catabolism; also, a step in the synthesis of NAD+ from t.. SYN: pyrrolase, t. oxygenase, t. pyrrolase, tryptophanase (1).- t. synthase a nonmammalian hydro-lyase condensing l-serine indole-3-glycerol phosphate to produce l-t. and glyceraldehyde phosphate; pyridoxal phosphate is required; it will also react l-serine with indole. SYN: t. desmolase, t. synthetase.
* * *tryp·to·phan 'trip-tə-.fan also tryp·to·phane -.fān n a crystalline essential amino acid C11H12N2O2 that is widely distributed in proteins abbr. Trp
* * *n.
* * *tryp·to·phan (Trp) (W) (tripґto-fan) an essential amino acid, α-amino-3-indolepropionic acid, existing in proteins, from which it is set free by tryptic digestion; necessary for optimal growth in infants and for nitrogen equilibrium in human adults. It is a precursor of serotonin. Adequate levels of tryptophan in the diet may compensate for deficiencies of niacin and thus mitigate pellagra. See also table at amino acid. [USP] a preparation of tryptophan used as a dietary supplement.
Medical dictionary. 2011.