Figure 1.

A: Ribbon diagram of SARS RNA‐dependent RNA polymerase. The characteristic fold of a “right hand” fingers, palm, and thumb can be recognized from residues 396 to 870 of nsP12. B: Structural detail of the active site of SARS RNA‐dependent RNA polymerase. The catalytic residues critical for the nucleotidyl transfer reactions are R553 and R555 and K551. D760 and D761 are responsible for the coordination of the metal ion. C: Structure of nucleoside analogs: derivatives from molecule X are XA1: R1 = OH; R2 = CH₂OH, XA2; R1 = CH₂OH; R2 = CH₂OH. D: Nucleoside analogue, 2′‐O‐methylcytidine and uridine triphosphate (UTP) docking in SARS RdR polymerase using GOLD.