3RPK:
reference: Structure of the Full-Length Major Pilin from Streptococcus pneumoniae: Implications for Isopeptide Bond Formation in Gram-Positive Bacterial Pili., Paterson NG, Baker EN, PLoS One. 2011;6(7):e22095. Epub 2011 Jul 8. PMID: 21760959

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