The primary structure of a protein refers to the number of polypeptide chains in it, the amino acid sequence of each, and the position of inter-and intrachain disulfide bridges. The secondary structure refers to the type of helical configuration possessed by each polypeptide chain resulting from the formation of intramolecular hydrogen bonds along its length. The tertiary structure refers to the manner in which each chain folds upon itself. The quaternary structure refers to the way two or more of the component chains may interact. See Chronology, 1951, Pauling and Corey; 1955, Sanger et al.; 1973, Anfinsen; alpha helix, beta pleated sheet.
Subjects: Genetics and Genomics.