4CJA:
reference: BuD, a helix-loop-helix DNA-binding domain for genome modification., Stella S, Molina R, Lopez-Mendez B, Juillerat A, Bertonati C, Daboussi F, Campos-Olivas R, Duchateau P, Montoya G, Acta Crystallogr D Biol Crystallogr. 2014 Jul 1;70(Pt 7):2042-52. doi:, 10.1107/S1399004714011183. Epub 2014 Jun 29. PMID: 25004980

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