6G0C:
reference: Insights into catalysis and function of phosphoribosyl-linked serine ubiquitination., Kalayil S, Bhogaraju S, Bonn F, Shin D, Liu Y, Gan N, Basquin J, Grumati P, Luo ZQ, Dikic I, Nature. 2018 May;557(7707):734-738. doi: 10.1038/s41586-018-0145-8. Epub 2018 May, 23. PMID: 29795347

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