1SW5:
reference: Structural basis for the binding of compatible solutes by ProX from the hyperthermophilic archaeon Archaeoglobus fulgidus., Schiefner A, Holtmann G, Diederichs K, Welte W, Bremer E, J Biol Chem 2004 Aug 11;. PMID: 15308642

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