2CAJ:
reference: Structural basis of the nickel response in Helicobacter pylori: crystal structures of HpNikR in Apo and nickel-bound states., Dian C, Schauer K, Kapp U, McSweeney SM, Labigne A, Terradot L, J Mol Biol. 2006 Aug 25;361(4):715-30. Epub 2006 Jul 7. PMID: 16872629

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