3ADR:
reference: The first crystal structure of an archaeal metallo-beta-lactamase superfamily protein; ST1585 from Sulfolobus tokodaii., Shimada A, Ishikawa H, Nakagawa N, Kuramitsu S, Masui R, Proteins. 2010 Aug 1;78(10):2399-402. PMID: 20544975

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