2XOD:
reference: High-resolution crystal structures of the flavoprotein NrdI in oxidized and reduced states--an unusual flavodoxin. Structural biology., Johansson R, Torrents E, Lundin D, Sprenger J, Sahlin M, Sjoberg BM, Logan DT, FEBS J. 2010 Oct;277(20):4265-77. doi: 10.1111/j.1742-4658.2010.07815.x., Epub 2010 Sep 10. PMID: 20831589

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