5CG6:
reference: Protonation State and Hydration of Bisphosphonate Bound to Farnesyl Pyrophosphate Synthase., Yokoyama T, Mizuguchi M, Ostermann A, Kusaka K, Niimura N, Schrader TE, Tanaka I, J Med Chem. 2015 Sep 24;58(18):7549-56. doi: 10.1021/acs.jmedchem.5b01147. Epub, 2015 Sep 4. PMID: 26314394

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