5FMN:
reference: A tight tunable range for Ni(II) sensing and buffering in cells., Foster AW, Pernil R, Patterson CJ, Scott AJ, Palsson LO, Pal R, Cummins I, Chivers PT, Pohl E, Robinson NJ, Nat Chem Biol. 2017 Feb 6. doi: 10.1038/nchembio.2310. PMID: 28166209

This OCA Structure page
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