... bonds with the mainchain oxygen of Gly68, and also, in some molecules, with the main chain oxygen of Arg67. This appears tohelp to maintain the functional conformation of thephosphate-binding ... possible binding subsites of RNase Sa2, fourdinucleotides and 16 combinations of trinucleotides, allhaving a guanine as the leading base, were docked intothe active site of the enzyme. In the ... into the base-binding site. In addition, guanine underwent a stacking interaction with Phe39 and interacted with Arg42. Guanine formsthe most efficient hydrogen-bonding network with theenzyme,...