1QWZ:
reference: The structure of sortase B, a cysteine transpeptidase that tethers surface protein to the Staphylococcus aureus cell wall., Zong Y, Mazmanian SK, Schneewind O, Narayana SV, Structure (Camb) 2004 Jan;12(1):105-12. PMID: 14725770

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