2XKV:
reference: Cryo-EM structure of the E. coli translating ribosome in complex with SRP and its receptor., Estrozi LF, Boehringer D, Shan SO, Ban N, Schaffitzel C, Nat Struct Mol Biol. 2011 Jan;18(1):88-90. Epub 2010 Dec 12. PMID: 21151118

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