5IXJ:
reference: Synthesis of beta-Branched Tryptophan Analogues Using an Engineered Subunit of Tryptophan Synthase., Herger M, van Roye P, Romney DK, Brinkmann-Chen S, Buller AR, Arnold FH, J Am Chem Soc. 2016 Jul 13;138(27):8388-91. doi: 10.1021/jacs.6b04836. Epub 2016 , Jul 1. PMID: 27355405

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