FIGURE 7.

Restoration of single round transcription by the ω₆ RNAP holoenzyme bearing the β′₂₁₁₂ subunit. A, single round transcription assays at T7A1 promoter template were performed with reconstituted RNAP holoenzymes (enzyme and promoter concentrations are indicated) in the absence (−) or presence (+) of rifampicin (Rif). WT denotes purified RNAP holoenzyme isolated from cell extract. B, comparative transcription efficiencies of the WT RNAP holoenzyme and reconstituted RNAP holoenzymes. Enzyme and promoter concentrations used are 2 and 0.2 pmol, respectively. C, quantified relative transcriptional activity of the various RNAP preparations. Bar 1 shows transcription from isolated wild-type RNAP; bars 2–5 show transcription with reconstituted RNAP preparations. Transcription reactions contained 2 pmol of enzyme and 0.2 pmol of T7A1 promoter DNA. Error bars represent S.E.