5MKG:
reference: Dimerisation induced formation of the active site and the identification of three metal sites in EAL-phosphodiesterases., Bellini D, Horrell S, Hutchin A, Phippen CW, Strange RW, Cai Y, Wagner A, Webb JS, Tews I, Walsh MA, Sci Rep. 2017 Feb 10;7:42166. doi: 10.1038/srep42166. PMID: 28186120

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