3OCP:
reference: Co-Crystal Structures of PKG Ibeta (92-227) with cGMP and cAMP Reveal the Molecular Details of Cyclic-Nucleotide Binding., Kim JJ, Casteel DE, Huang G, Kwon TH, Ren RK, Zwart P, Headd JJ, Brown NG, Chow DC, Palzkill T, Kim C, PLoS One. 2011 Apr 19;6(4):e18413. PMID: 21526164

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