2KW8:
reference: The Sortase A enzyme that attaches proteins to the cell wall of Bacillus anthracis contains an unusual active site architecture., Weiner EM, Robson S, Marohn M, Clubb RT, J Biol Chem. 2010 Jul 23;285(30):23433-43. Epub 2010 May 19. PMID: 20489200

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