2GEG:
reference: Molecular model of human CYP21 based on mammalian CYP2C5: structural features correlate with clinical severity of mutations causing congenital adrenal hyperplasia., Robins T, Carlsson J, Sunnerhagen M, Wedell A, Persson B, Mol Endocrinol. 2006 Nov;20(11):2946-64. Epub 2006 Jun 20. PMID: 16788163

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