4FGQ:
reference: Structural characterization of a conserved, calcium-dependent periplasmic protease from Legionella pneumophila., Chatterjee D, Boyd CD, O'Toole GA, Sondermann H, J Bacteriol. 2012 Aug;194(16):4415-25. doi: 10.1128/JB.00640-12. Epub 2012 Jun, 15. PMID: 22707706

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