tryptophan (Trp W)

Term: tryptophan (Trp W)

Literally meaning: “to be broken and to appear”

Origin: Anc Greek

τρίβω/trivo (=to rub, to powder, to grind) > (simple past) ἔτριψα/etripsα >τρύω/tryo(=to puncture)

φαίνω/pheno(=be visible, or obvious, show)

Coined/History 

Tryptophan discovered by Frederick Hopkins (1861-1947) through casein hydrolysis. Hopkins was first who referred to those amino acids  that are not manufactured by body and they must be taken by diet. The name of tryptophan was first used by Neumeister in 1890 concerning the substance present in tryptic digests of proteins.

Definition

Tryptophan is an essential amino acid (cannot be synthesized by the organism)  which contains an indole functional group. It is precursor for the serotonin (neurotransmitter) auxin (phytohormone) and niacin (vitamin).  It is found in foods such as chocolate, yogurt, cottage cheese, eggs, sesame seeds, dried spirulina and bananas.

chymotrypsin

Term: chymotrypsin

Literally meaning: “protein of rubbing juices”

Origin: Greek

χυμός/chymos(=juice)   > χέω/cheo(=pour)

+  τρίβω/trivo (=rub, powder, grind) > (simple past) ἔτριψα /etripsα

Coined/History 

In 1934 M. Κunitz and J.H.Northrop were able to isolate and crystallize from pancreatic preparations an enzyme, in adition to trypsin, named chemotrypsin as well as the inactive precursor, chymotrypsinogen (J. Gen. Physiol., 17, 1934). Four years later Kunitz was able to isolate different active forms of the enzyme called them as alpha, beta, and gama. 

Definition

Chymothrepsin is a proteolytic enzyme that cleaves the peptide bonds at carboxy site of aromatic residues (tyrosine, phenylalanine, and tryptophan). Chymotrepsin is active in the intestine  produced by the acinar cells of the pancreas. Chymotrepsin becomes activated after proteolysis of chemotrypsinogen by trypsin.