1SS2:
reference: Structural analysis of the CCP modules of the GABAB receptor 1a: Only one of the two CCP modules is compactly folded., Blein S, Ginham R, Uhrin D, Smith BO, Soares DC, Veltel S, McIllhinney JR, White JH, Barlow PN, J Biol Chem 2004 Aug 9;. PMID: 15304491

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