1FWZ:
reference: Structures of three diphtheria toxin repressor (DtxR) variants with decreased repressor activity., Pohl E, Goranson-Siekierke J, Choi MK, Roosild T, Holmes RK, Hol WG, Acta Crystallogr D Biol Crystallogr 2001 May;57(Pt 5):619-27. PMID: 11320302

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