4LDZ:
reference: Allosteric activation of bacterial response regulators: the role of the cognate histidine kinase beyond phosphorylation., Trajtenberg F, Albanesi D, Ruetalo N, Botti H, Mechaly AE, Nieves M, Aguilar PS, Cybulski L, Larrieux N, de Mendoza D, Buschiazzo A, MBio. 2014 Nov 18;5(6):e02105. doi: 10.1128/mBio.02105-14. PMID: 25406381

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