General Info 

   Metabolic Role 






HTML version Author: Kimberly Dick   

Tryptophan Tryptophan

Symbol trp w
Molecular formula C11H12N2O2
Molecular weight 204.23
Isoelectric point (pH) 5.89
CAS Registry Number 73-22-3

Tryptophan is one of eight essential amino acids, necessary for the development of the vitamin niacin. It cannot be synthesized in the human body and thus must be obtained from food or supplements. Tryptophan is necessary for the production of several crucial substances in the body, including the neurotransmitter serotonin (5-hydroxytryptamine). Because serotonin (a melatonin precursor) plays a key role in mood and sleep patterns, tryptophan supplements have been used for some time as antidepressants, sleep aids, and weight-loss aids.

Tryptophan, however, is a substance with a colorful political history. In 1989, tryptophan supplements (specifically, the optical isomer L-tryptophan) were linked to a series of deaths and subsequently removed from the market. As the production of these supplements involved genetically engineered bacteria, L-tryptophan has become an example for those opposed to genetic engineering, as well as those condemning the involvement of government in drug development. Currently, this drug is banned by the FDA as a supplement for human use. It is, however, still available in many countries including Canada, Germany, the Netherlands and Great Britain.

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