1XFR:
reference: Dynamic conformational equilibria in the physiological function of the Bombyx mori pheromone-binding protein., Michel E, Damberger FF, Ishida Y, Fiorito F, Lee D, Leal WS, Wuthrich K, J Mol Biol. 2011 May 20;408(5):922-31. Epub 2011 Mar 17. PMID: 21396939

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