4HF1:
reference: Studies of IscR reveal a unique mechanism for metal-dependent regulation of DNA binding specificity., Rajagopalan S, Teter SJ, Zwart PH, Brennan RG, Phillips KJ, Kiley PJ, Nat Struct Mol Biol. 2013 Jun;20(6):740-7. doi: 10.1038/nsmb.2568. Epub 2013 May , 5. PMID: 23644595

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