Moreover, the location of their
less-ordered nucleoside moieties indicates a relatively hydrophobic
pocket (N site). His41 is also involved in both the N site and the ribose binding site (R site). In sharp contrast,
unambiguous electron density indicates that rGMP and
rCMP will not bind into this site, suggesting that this binding
site has substrate specificity. The results reported here provide
a more-detailed picture of PAN nuclease cleavage and
provide a distinct binding pocket for anti-influenza drug
discovery targeting the cap-dependent endonuclease.