Inhibition of poliovirus polymerase by guanidine in vitro.

Extracts from poliovirus-infected HeLa cells synthesized 35s viral RNA, replicative intermediate, and double-stranded RNA in vitro. Guanidine inhibited the synthesis of all three species of RNA; production of 35s RNA was most sensitive to the inhibitor. Pulse-chase experiments with [3H]UTP indicated that guanidine had no detectable effect on elongation of polynucleotide chains or the release of completed RNA chains from the viral replication complex. Experiments in which short pulses of precursor were used suggest that guanidine blocked the initiation step of RNA synthesis in vitro.