2HXX:
reference: Aminotryptophan-containing barstar: structure--function tradeoff in protein design and engineering with an expanded genetic code., Rubini M, Lepthien S, Golbik R, Budisa N, Biochim Biophys Acta. 2006 Jul;1764(7):1147-58. Epub 2006 May 10. PMID: 16782415

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