1G5C:
reference: Crystal structure of the "cab"-type beta class carbonic anhydrase from the archaeon Methanobacterium thermoautotrophicum., Strop P, Smith KS, Iverson TM, Ferry JG, Rees DC, J Biol Chem 2001 Mar 30;276(13):10299-305. PMID: 11096105

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