Acid Quote by Linus Pauling
“An amino acid residue (other than glycine) has no symmetry elements. The general operation of conversion of one residue of a single chain into a second residue equivalent to the first is accordingly a rotation about an axis accompanied by translation along the axis. Hence the only configurations for a chain compatible with our postulate of equivalence of the residues are helical configurations.”
![“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)
![“[Professor Pauling] confesses that he had harboured the feeling that sooner or later he would be the one to get the DNA structure; and although he was pleased with the double-helix, he 'rather wished the idea had been his'.” quote by Linus Pauling](https://sms4smile.com/quotes/img-quotes/d71/linus-pauling-8508_dna_professor-pauling-confesses-that-he-had_319556.jpg)
