FIG 4.

Top view of the RdRp from CVB3 (PDB code 3CDW). (A) The locations of the residues K159 and A239 are highlighted in purple and red, respectively. The channel from incoming ribonucleoside triphosphates (rNTPs) is shown between these residues. (B) The long chain of the arginine residue R159 mutant is highlighted in purple, narrowing the channel for incoming rNTPs. A239 is shown in red. (C) The G239 mutant, in red, is able to reestablish the access of rNTPs in the channel. The residue R159 is shown in purple. Panels D to F are representative zoom images of panels A to C, respectively.