4NMF:
reference: Structures of the PutA peripheral membrane flavoenzyme reveal a dynamic substrate-channeling tunnel and the quinone-binding site., Singh H, Arentson BW, Becker DF, Tanner JJ, Proc Natl Acad Sci U S A. 2014 Mar 4;111(9):3389-94. doi:, 10.1073/pnas.1321621111. Epub 2014 Feb 18. PMID: 24550478

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