Figure 5.

Holoenzyme complexes lacking Region I are transcriptionally active on heteroduplex DNA without activator. Holoenzymes (100 nm) with GTP or ATP (1 mm) in the presence or absence of PspFΔHTH (4 μm) were used to transcribe the 88-mer homoduplex and heteroduplex 1 (16 nm) templates. Core RNAP and holoenzyme containing the DNA nonbinding 1–424 σ derivative (Cannon et al. 1995b) were used as controls. The location of the DNA size markers are shown (arrows). (A) [α-³²P]UTP-labeled transcripts with GTP as the hydrolyzable nucleotide used by activator. (B) [γ-³²P]GTP-labeled transcripts with ATP as the hydrolyzable nucleotide used by activator.