1JC4:
reference: Crystal structure of methylmalonyl-coenzyme A epimerase from P. shermanii: a novel enzymatic function on an ancient metal binding scaffold., McCarthy AA, Baker HM, Shewry SC, Patchett ML, Baker EN, Structure (Camb) 2001 Jul 3;9(7):637-46. PMID: 11470438

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