“In describing a protein it is now common to distinguish the primary, secondary and tertiary structures. The primary structure is simply the order, or sequence, of the amino-acid residues along the polypeptide chains. This was first determined by [Frederick] Sanger… — John Kendrew Copy Share Image
![“In describing a protein it is now common to distinguish the primary, secondary and tertiary structures. The primary structure is simply the order, or sequence, of the amino-acid residues along the polypeptide chains. This was first determined by [Frederick] Sanger using chemical techniques for the…” quote by John Kendrew](https://sms4smile.com/quotes/img-quotes/805/john-kendrew-166387_amino-acid_in-describing-a-protein-it-is-now-common_1314282.jpg)