PMID:10811806
| Citation |
Nechaev, S, Chlenov, M and Severinov, K (2000) Dissection of two hallmarks of the open promoter complex by mutation in an RNA polymerase core subunit. J. Biol. Chem. 275:25516-22 |
|---|---|
| Abstract |
Deletion of 10 evolutionarily conserved amino acids from the beta subunit of Escherichia coli RNA polymerase leads to a mutant enzyme that is unable to efficiently hold onto DNA. Open promoter complexes formed by the mutant enzyme are in rapid equilibrium with closed complexes and, unlike the wild-type complexes, are highly sensitive to the DNA competitor heparin (Martin, E., Sagitov, V., Burova, E., Nikiforov, V., and Goldfarb, A. (1992) J. Biol. Chem. 267, 20175-20180). Here we show that despite this instability, the mutant enzyme forms partially open complexes at temperatures as low as 0 degrees C when the wild-type complex is fully closed. Thus, the two hallmarks of the open promoter complex, the stability toward a challenge with DNA competitors and the sensitivity toward low temperature, can be uncoupled by mutation and may be independent in the wild-type complex. We use the high resolution structure of Thermus aquaticus RNA polymerase core to build a functional model of promoter complex formation that accounts for the observed defects of the E. coli RNA polymerase mutants. |
| Links |
PubMed Online version:10.1074/jbc.M002511200 |
| Keywords |
Amino Acid Sequence; Bacillus subtilis/enzymology; Catalytic Domain; DNA Footprinting; DNA-Directed RNA Polymerases/genetics; DNA-Directed RNA Polymerases/metabolism; Enzyme Stability/genetics; Escherichia coli/enzymology; Gene Deletion; Molecular Sequence Data; Mutation; Plasmids/metabolism; Promoter Regions, Genetic; Protein Conformation; Sequence Homology, Amino Acid; Temperature; Thermus/enzymology; Transcription, Genetic/genetics |
| edit table |
Significance
You can help EcoliWiki by summarizing why this paper is useful
Useful Materials and Methods
You can help Ecoliwiki by describing the useful materials (strains, plasmids, antibodies, etc) described in this paper.
Annotations
<annotationlinks/>
EcoliWiki Links
Add links to pages that link here (e.g. gene, product, method pages)
References
See Help:References for how to manage references in EcoliWiki.