Translations:Insulin/73/en

Structural analysis and synthesis

Richardson diagram of a porcine insulin monomer, showing its characteristic secondary structure. This is the biologically active form of insulin.

Richardson diagram of a porcine insulin hexamer. The sphere at the center is a stabilizing zinc atom, surrounded by coordinating histidine residues. This is the form in which insulin is stored in beta cells. PDB: 4INS​.

Purified animal-sourced insulin was initially the only type of insulin available for experiments and diabetics. John Jacob Abel was the first to produce the crystallised form in 1926. Evidence of the protein nature was first given by Michael Somogyi, Edward A. Doisy, and Philip A. Shaffer in 1924. It was fully proven when Hans Jensen and Earl A. Evans Jr. isolated the amino acids phenylalanine and proline in 1935.