https://www.jenabioscience.com/nucleotides-nucleosides/nucleotides-by-application/on-proteins-enzymes/structural-biology/non-hydrolyzable-nucleotides/beta-gamma-non-hydrolyzable-nucleotides/guanosine-nucleotides/nu-402-gppcp-gmppcp
GppCp, β,γ non-hydrolyzable Guanosine Nucleotides - Jena Bioscience
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