6DS2:
reference: Biophysical Examination of the Calcium-Modulated Nickel-Binding Properties of Human Calprotectin Reveals Conformational Change in the EF-Hand Domains and His3Asp Site., Nakashige TG, Bowman SEJ, Zygiel EM, Drennan CL, Nolan EM, Biochemistry. 2018 Jun 26. doi: 10.1021/acs.biochem.8b00415. PMID: 29890074

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