1A4S:
reference: Structure of betaine aldehyde dehydrogenase at 2.1 A resolution., Johansson K, El-Ahmad M, Ramaswamy S, Hjelmqvist L, Jornvall H, Eklund H, Protein Sci 1998 Oct;7(10):2106-17. PMID: 9792097

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