Discovery of protein and amino acid

The early history of protein metabolism and nutrition is closely tied to the discovery of nitrogen and its distribution in nature.

Daniel Rutherford, in Edinburgh, can be regarded as the discoverer of nitrogen, which he called ‘phlogisticated air’ in his doctoral dissertation of Doctorate of Medicine at the University of Edinburgh in Medicine thesis in 1772.

Rutherford showed that the gas was incapable of supporting life or flame, work later extended by the French chemist Lavoisier.

In 1789, The French chemist Antoine Fourcroy recognized three distinct varieties of protein from animal sources: albumin, fibrin, and gelatin.

In 1806 Louis Nicolas Vauquelin, a French chemist, isolated asparagines, a compound in asparagus a that turned out to be the first amino acid occurring in protein to be discovered. While the second amino acid cystine was discovered by William Hyde Wallaston in 1810. The discovery of all amino acids ending with discovery of threonine in 1935.

The association between protein quality and amino acid composition was first shown by Willcock and Hopkins in 1906 when they postulated the essentiality of tryptophan.

The term protein was invented by the Swedish chemistry Jons Jakob Berzelius (1779-1848). The name is derived from the Greek word πρωτεῖος which mean ‘standing in front’, ‘in the lead’.

Berzelius justified the name in a letter to Gerrit Mulder, Dutch physician and chemist, dated 10 July 1838. 

Protein purification began in the first half of the nineteenth century upon the discovery of the first proteins: albumin, hemoglobin, casein, pepsin, fibrin and crystalline.
Discovery of protein and amino acid