Tryptophan

related topics
{disease, patient, cell}
{acid, form, water}
{food, make, wine}
{area, community, home}
{water, park, boat}
{law, state, case}

11.4 g/L at 25 °C,
17.1 g/L at 50 °C,
27.95 g/L at 75 °C

Tryptophan (IUPAC-IUBMB abbreviation: Trp or W; IUPAC abbreviation: L-Trp or D-Trp; sold for medical use as Tryptan)[2] is one of the 20 standard amino acids, as well as an essential amino acid in the human diet. It is encoded in the standard genetic code as the codon UGG. The slight mispronunciation "tWiptophan" can be used as a mnemonic for its single letter IUPAC code W.[3] Only the L-stereoisomer of tryptophan is used in structural or enzyme proteins, but the D-stereoisomer is occasionally found in naturally produced peptides (for example, the marine venom peptide contryphan).[4] The distinguishing structural characteristic of tryptophan is that it contains an indole functional group. It is an essential amino acid as demonstrated by its growth effects on rats.

Contents

Isolation

The isolation of tryptophan was first reported by Frederick Hopkins in 1901[5] through hydrolysis of casein. From 600 grams of crude casein one obtains 4-8 grams of tryptophan.[6]

Biosynthesis and industrial production

Plants and microorganisms commonly synthesize tryptophan from shikimic acid or anthranilate.[7] The latter condenses with phosphoribosylpyrophosphate (PRPP), generating pyrophosphate as a by-product. After ring opening of the ribose moiety and following reductive decarboxylation, indole-3-glycerinephosphate is produced, which in turn is transformed into indole. In the last step, tryptophan synthase catalyzes the formation of tryptophan from indole and the amino acid serine.

Full article ▸

related documents
Guar gum
Chemotaxis
Phenylalanine
Salvinorin A
Sarin
Taurine
Immunoperoxidase
Lipoic acid
RNA interference
Triglyceride
Bacteriocin
Ketosis
Glutamine
Tabun (nerve agent)
Nitrogen narcosis
Prostaglandin
Lipoprotein
Fibroblast
Creosote
Fibronectin
Fat
Large intestine
Myoglobin
Hemocyanin
Bacteriophage
Biotin
Hexokinase
Syringe
Hygiene
Virus classification