5C5E:
reference: Protein-Protein Interactions in the Cyanobacterial Circadian Clock: Structure of KaiA Dimer in Complex with C-Terminal KaiC Peptides at 2.8 A Resolution., Pattanayek R, Egli M, Biochemistry. 2015 Aug 4;54(30):4575-8. doi: 10.1021/acs.biochem.5b00694. Epub, 2015 Jul 24. PMID: 26200123

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