RNA polymerase-promoter interactions determining different stability of the Escherichia coli and Thermus aquaticus transcription initiation complexes.

ABSTRACT: Transcription initiation complexes formed by bacterial RNA polymerases (RNAPs) exhibit dramatic species-specific differences in stability, leading to different strategies of transcription regulation. The molecular basis for this diversity is unclear. Promoter complexes formed by RNAP from Thermus aquaticus (Taq) are considerably less stable than Escherichia coli RNAP promoter complexes, particularly at temperatures below 37°C. Here, we used a fluorometric RNAP molecular beacon assay to discern partial RNAP-promoter interactions. We quantitatively compared the strength of E. coli and Taq RNAPs partial interactions with the -10, -35 and UP promoter elements; the TG motif of the extended -10 element; the discriminator and the downstream duplex promoter segments. We found that compared with Ta

SUBMITTER: Mekler V 

PROVIDER: S-EPMC3526302 | biostudies-literature | 2012 Dec

REPOSITORIES: biostudies-literature