4XB4:
reference: PHOTOSYNTHESIS. A 12 A carotenoid translocation in a photoswitch associated with cyanobacterial photoprotection., Leverenz RL, Sutter M, Wilson A, Gupta S, Thurotte A, Bourcier de Carbon C, Petzold CJ, Ralston C, Perreau F, Kirilovsky D, Kerfeld CA, Science. 2015 Jun 26;348(6242):1463-6. doi: 10.1126/science.aaa7234. PMID: 26113721

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