Amino acid
Amino acids are organic compounds containing amine (-NH) and carboxyl (-COOH) functional groups, along with a side chain (R group) specific to each amino acid. The key elements of an amino acid are carbon (C), hydrogen (H), oxygen (O), and nitrogen (N), although other elements are found in the side chains of certain amino acids. About 500 naturally occurring amino acids are known (though only 20 appear in the genetic code) and can be classified in many ways. They can be classified according to the core structural functional groups' locations as alpha- (α-), beta- (β-), gamma- (γ-) or delta- (δ-) amino acids; other categories relate to polarity, pH level, and side chain group type (aliphatic, acyclic, aromatic, containing hydroxyl or sulfur, etc.). In the form of proteins, amino acid residues form the second-largest component (water is the largest) of human muscles and other tissues. Beyond their role as residues in proteins, amino acids participate in a number of processes such as neurotransmitter transport and biosynthesis.
Louis Nicolas Vauquelin
From 1809 he was professor at the University of Paris. In 1816, he was elected a foreign member of the Royal Swedish Academy of Sciences. He was elected to the Chamber of Deputies in 1828. In 1806, working with asparagus, he and Pierre Jean Robiquet (future discoverer of the famous red dye alizarin, then a young chemist and his assistant) isolated the amino acid asparagine, the first one to be discovered. He also discovered pectin and malic acid in apples, and isolated camphoric acid and quinic acid.