2K0D:
reference: Amino acid insertion reveals a necessary three-helical intermediate in the folding pathway of the colicin E7 immunity protein Im7., Knowling SE, Figueiredo AM, Whittaker SB, Moore GR, Radford SE, J Mol Biol. 2009 Oct 2;392(4):1074-86. Epub 2009 Aug 3. PMID: 19651139

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