4OH2:
reference: Copper-Based Pulsed Dipolar ESR Spectroscopy as a Probe of Protein Conformation Linked to Disease States., Merz GE, Borbat PP, Pratt AJ, Getzoff ED, Freed JH, Crane BR, Biophys J. 2014 Oct 7;107(7):1669-74. doi: 10.1016/j.bpj.2014.07.068. PMID: 25296320

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