4MLT:
reference: 'Unconventional' coordination chemistry by metal chelating fragments in a metalloprotein active site., Martin DP, Blachly PG, Marts AR, Woodruff TM, de Oliveira CA, McCammon JA, Tierney DL, Cohen SM, J Am Chem Soc. 2014 Apr 9;136(14):5400-6. doi: 10.1021/ja500616m. Epub 2014 Mar, 27. PMID: 24635441

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