3RCC:
reference: Structural differences between the Streptococcus agalactiae housekeeping and pilus-specific sortases: SrtA and SrtC1., Khare B, Krishnan V, Rajashankar KR, I-Hsiu H, Xin M, Ton-That H, Narayana SV, PLoS One. 2011;6(8):e22995. Epub 2011 Aug 30. PMID: 21912586

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