Related Experiment Video
Updated: Aug 17, 2026

On-chip Isotachophoresis for Separation of Ions and Purification of Nucleic Acids
Published on: March 2, 2012
Identification of a component separated on Mono Q purification of Escherichia coli RNA polymerase as an NTPase
1NIH/NIA, Gerontology Research Center, Baltimore, MD 21224.
Abstract:
Standard preparations of Escherichia coli RNA polymerase (RNAP) contain NTPase activity. High-performance anion-exchange chromatography on Mono Q has recently been used by Hager et al. [1990, Biochemistry 29, 7890-7894] to fractionate RNAP into holoenzyme (alpha 2 beta beta' sigma) and core (alpha 2 beta beta') forms, plus other protein components. We found that one of these components, of protomer size slightly larger than the sigma 70 subunit, has NTPase activity; it is efficiently separated on Mono Q, leaving transcriptionally active holoenzyme and core apparently free of NTPase activity. Because of the similarity in size with sigma 70, the NTPase component may escape detection by routine gel electrophoresis.
More Related Videos
Related Concept Videos
Bacterial RNA Polymerase
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
Eukaryotic RNA Polymerases
All three eukaryotic RNAPs require specific transcription factors, of which the...
Transcription Initiation
The promoters and enhancers and their accessory proteins allow tight regulation of...

