1AMU:
reference: Structural basis for the activation of phenylalanine in the non-ribosomal biosynthesis of gramicidin S., Conti E, Stachelhaus T, Marahiel MA, Brick P, EMBO J 1997 Jul 16;16(14):4174-83. PMID: 9250661

This OCA Structure page
uses Jmol, developed by the Jmol Development Team (documentation).