1BQG:
reference: Evolution of enzymatic activities in the enolase superfamily: crystal structure of (D)-glucarate dehydratase from Pseudomonas putida., Gulick AM, Palmer DR, Babbitt PC, Gerlt JA, Rayment I, Biochemistry 1998 Oct 13;37(41):14358-68. PMID: 9772161

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