3OD2:
reference: Structural Basis of Low-Affinity Nickel Binding to the Nickel-Responsive Transcription Factor NikR from Escherichia coli., Phillips CM, Schreiter ER, Stultz CM, Drennan CL, Biochemistry. 2010 Sep 14;49(36):7830-8. PMID: 20704276

This OCA Structure page
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