An NTP-driven mechanism for the nucleotide addition cycle of Escherichia coli RNA polymerase during transcription.

ABSTRACT: The elementary steps of transcription as catalyzed by E. coli RNA polymerase during one and two rounds of the nucleotide addition cycle (NAC) were resolved in rapid kinetic studies. Modelling of stopped-flow kinetic data of pyrophosphate release in a coupled enzyme assay during one round of the NAC indicates that the rate of pyrophosphate release is significantly less than that for nucleotide incorporation. Upon modelling of the stopped-flow kinetic data for pyrophosphate release during two rounds of the NAC, it was observed that the presence of the next nucleotide for incorporation increases the rate of release of the first pyrophosphate equivalent; incorrect nucleotides for incorporation had no effect on the rate of pyrophosphate release. Although the next nucleotide for incorporation in

SUBMITTER: Johnson RS 

PROVIDER: S-EPMC9595533 | biostudies-literature | 2022

REPOSITORIES: biostudies-literature