5FD4:
reference: Pheromone Recognition and Selectivity by ComR Proteins among Streptococcus Species., Shanker E, Morrison DA, Talagas A, Nessler S, Federle MJ, Prehna G, PLoS Pathog. 2016 Dec 1;12(12):e1005979. doi: 10.1371/journal.ppat.1005979., eCollection 2016 Dec. PMID: 27907154

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