What is Tryptophan?
[[File:L-Tryptophan - L-Tryptophan.svg|thumb|250px|L-[[isomer]] of Tryptophan]] '''Tryptophan''' ('''Trp''' or '''W''') is encoded by the [[codon]] '''UGG'''. It is an α-[[amino acid]] used in the bio[[synthesis]] of [[protein]]s. Tryptophan has an α-amino group (which is in the –NH<sub>3</sub><sup>+</sup> form under biological conditions), and an α-[[carboxylic acid]] group (which is in the [[Deprotonation|deprotonated]] –COO<sup>−</sup> form under [[Biology|biological]] conditions). It also has a side chain [[indole]], which makes it a non-polar [[Aromatic hydrocarbon|aromatic]] amino acid. Tryptophan is [[Essential amino acid|essential]] to humans: the body cannot synthesize it, so it must be obtained from the diet. Tryptophan is also a [[precursor]] to the [[neurotransmitter]]s [[serotonin]] and [[melatonin]].<ref>{{cite journal | title = Conversion of L-tryptophan to serotonin and melatonin in human melanoma cells | journal = FEBS Letters | year = 2002 | volume = 511 | issue = 1–3 | pages = 102–6 | pmid = 11821057 | doi = 10.1016/s0014-5793(01)03319-1 | s2cid = 7820568 | last1 = Slominski | first1 = Andrzej | last2 = Semak | first2 = Igor | last3 = Pisarchik | first3 = Alexander | last4 = Sweatman | first4 = Trevor | last5 = Szczesniewski | first5 = Andre | last6 = Wortsman | first6 = Jacobo }}</ref> People get tryptophan by eating protein-rich foods like meat, eggs, and dairy products. == References == {{reflist}} {{Proteinogenic amino acids}} {{Amino acid metabolism intermediates}} {{Aryl hydrocarbon receptor modulators}} [[Category:Amino acids]]