Previous work has shown that the base sequence of the DNA segment immediately upstream of the -10 hexamer at bacterial promoters (the extended -10 element) can make a significant contribution to promoter strength. Guided by recently published structural information, we used alanine scanning and suppression mutagenesis of Region 2.4 and Region 3.0 of the Escherichia coli RNA polymerase sigma(70) subunit to identify amino acid sidechains that play a role in recognition of this element. Our study shows that changes in these regions of the sigma(70) subunit can affect the recognition of different extended -10 element sequences. (C) 2003 Published by Elsevier Science B.V. on behalf of the Federation of European Biochemical Societies.
|Number of pages||7|
|Publication status||Published - 5 Jun 2003|
- bacterial transcription initiation
- sigma(70) subunit
- promoter recognition
- RNA polymerase
- extended-10 promoters