2KRF:
reference: NMR Solution Structure and DNA-binding Model of the DNA-binding Domain of Competence Protein A., Hobbs CA, Bobay BG, Thompson RJ, Perego M, Cavanagh J, J Mol Biol. 2010 Mar 17. PMID: 20302877

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