3DTM:
reference: Increased folding stability of TEM-1 beta-lactamase by in vitro selection., Kather I, Jakob RP, Dobbek H, Schmid FX, J Mol Biol. 2008 Oct 31;383(1):238-51. Epub 2008 Aug 3. PMID: 18706424

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