2H40:
reference: Multiple Conformations of Phosphodiesterase-5: IMPLICATIONS FOR ENZYME FUNCTION AND DRUG DEVELOPMENT., Wang H, Liu Y, Huai Q, Cai J, Zoraghi R, Francis SH, Corbin JD, Robinson H, Xin Z, Lin G, Ke H, J Biol Chem. 2006 Jul 28;281(30):21469-79. Epub 2006 May 30. PMID: 16735511

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