2R6O:
reference: Structural insight into the mechanism of c-di-GMP hydrolysis by EAL domain phosphodiesterases., Tchigvintsev A, Xu X, Singer A, Chang C, Brown G, Proudfoot M, Cui H, Flick R, Anderson WF, Joachimiak A, Galperin MY, Savchenko A, Yakunin AF, J Mol Biol. 2010 Sep 24;402(3):524-38. Epub 2010 Aug 4. PMID: 20691189

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