Contact: Catherine Kolf
Johns Hopkins Medicine
Caption: Four identical subunits make up the antiviral SAMHD1 enzyme. Each subunit must bind a molecule of GTP at its A1 site and an A, T, C or G nucleotide at its A2 site before the enzyme can break down additional A, T, C and G nucleotides at its S sites.
Credit: Stivers Lab, Johns Hopkins Medicine
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