4K39:
reference: X-ray structure of an AdoMet radical activase reveals an anaerobic solution for formylglycine posttranslational modification., Goldman PJ, Grove TL, Sites LA, McLaughlin MI, Booker SJ, Drennan CL, Proc Natl Acad Sci U S A. 2013 May 21;110(21):8519-24. doi:, 10.1073/pnas.1302417110. Epub 2013 May 6. PMID: 23650368

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