the model presented here confirms the earlier proposal [ rhoads et al . ( 1983 ) biochemistry 22 , 6084-6088 ] that the enolate tautomer of the cap is preferred for interaction and further proposes that the interaction is with a protonated amino acid residue , such as histidine , while stacking with an aromatic amino acid , such as tryptophan .
C0301713
aromatic amino
C0041249
tryptophan