6QKR:
reference: Low potential enzymatic hydride transfer via highly cooperative and inversely functionalized flavin cofactors., Willistein M, Bechtel DF, Muller CS, Demmer U, Heimann L, Kayastha K, Schunemann V, Pierik AJ, Ullmann GM, Ermler U, Boll M, Nat Commun. 2019 May 6;10(1):2074. doi: 10.1038/s41467-019-10078-3. PMID: 31061390

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