3ZGB:
reference: Greater efficiency of photosynthetic carbon fixation due to single amino-acid substitution., Paulus JK, Schlieper D, Groth G, Nat Commun. 2013 Feb 26;4:1518. doi: 10.1038/ncomms2504. PMID: 23443546

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