2QDI:
reference: Activation of pheromone-sensitive neurons is mediated by conformational activation of pheromone-binding protein., Laughlin JD, Ha TS, Jones DN, Smith DP, Cell. 2008 Jun 27;133(7):1255-65. PMID: 18585358

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