Novel architectural features of Bordetella pertussis fimbrial subunit promoters and their activation by the global virulence regulator BvgA
Open Access
- 25 August 2010
- journal article
- Published by Wiley in Molecular Microbiology
- Vol. 77 (5), 1326-1340
- https://doi.org/10.1111/j.1365-2958.2010.07293.x
Abstract
A prominent feature of the promoters of Bordetella pertussis fimbrial subunit genes fim2, fim3 and fimX is the presence of a ‘C‐stretch’, a monotonic run of C residues. The C‐stretch renders these genes capable of phase variation, through spontaneous variations in its length. For each of these we determined the length of the C‐stretch that gave maximal transcriptional activity, and found that the three optimized promoters align perfectly, with identical distances between conserved upstream sequences and the downstream −10 elements and transcriptional start sites. We also demonstrated, for Pfim3, that the conserved sequence corresponds to BvgA binding sites. The more upstream of the two binding sites is predicted to be high affinity, by comparison to a functionally derived consensus BvgA‐binding sequence. The other binding site is a fairly poor match to this consensus, with 10 of 14 bp belonging to the C‐stretch. Interestingly, the centre of this downstream site of BvgA binding coincides exactly with the centre of the expected typical location of a −35 sequence. However, the lack of a recognizable −35 element (CCCCCC versus TTGACA), and the occupation of this site by BvgA∼P suggest that activation of the fim promoters involves unusual interactions among BvgA, RNA polymerase and promoter DNA.Keywords
This publication has 41 references indexed in Scilit:
- Evolution of the Chaperone/Usher Assembly Pathway: Fimbrial Classification Goes GreekMicrobiology and Molecular Biology Reviews, 2007
- Mutational Analysis of σ70 Region 4 Needed for Appropriation by the Bacteriophage T4 Transcription Factors AsiA and MotAJournal of Molecular Biology, 2006
- Analysis of bvgR Expression in Bordetella pertussisJournal of Bacteriology, 2003
- The Response Regulator BvgA and RNA Polymerase α Subunit C-Terminal Domain Bind Simultaneously to Different Faces of the Same Segment of Promoter DNAMolecular Cell, 2003
- Domain 1.1 of the σ70 Subunit of Escherichia coli RNA Polymerase Modulates the Formation of Stable Polymerase/Promoter ComplexesJournal of Molecular Biology, 2001
- Efficient Inhibition of Escherichia Coli RNA Polymerase by the Bacteriophage T4 AsiA Protein Requires that AsiA Binds First to Free σ70Journal of Molecular Biology, 2000
- The Minus 35-Recognition Region of Escherichia coli Sigma 70 is Inessential for Initiation of Transcription at an "Extended Minus 10" PromoterJournal of Molecular Biology, 1993
- Use of bacteriophage T7 lysozyme to improve an inducible T7 expression systemJournal of Molecular Biology, 1991
- Transcriptional activation of bacteriophage T4 middle promoters by the motA proteinJournal of Molecular Biology, 1988
- A Broad Host Range Mobilization System for In Vivo Genetic Engineering: Transposon Mutagenesis in Gram Negative BacteriaBio/Technology, 1983