6VJG:
reference: Csx3 is a cyclic oligonucleotide phosphodiesterase associated with type-III CRISPR-Cas that degrades the second messenger cA4., Brown S, Gauvin CC, Charbonneau AA, Burman N, Lawrence CM, J Biol Chem. 2020 Aug 21. pii: RA120.014099. doi: 10.1074/jbc.RA120.014099. PMID: 32826317

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