2KKH:
reference: Metal binding affinities of Arabidopsis zinc and copper transporters: selectivities match the relative, but not the absolute, affinities of their amino-terminal domains., Zimmermann M, Clarke O, Gulbis JM, Keizer DW, Jarvis RS, Cobbett CS, Hinds MG, Xiao Z, Wedd AG, Biochemistry. 2009 Dec 15;48(49):11640-54. PMID: 19883117

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