3LSI:
reference: H-bonding and positive charge at the N5/O4 locus are critical for covalent flavin attachment in trametes pyranose 2-oxidase., Tan TC, Pitsawong W, Wongnate T, Spadiut O, Haltrich D, Chaiyen P, Divne C, J Mol Biol. 2010 Sep 24;402(3):578-94. Epub 2010 Aug 12. PMID: 20708626

This OCA Structure page
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