This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Carbonetti, N H Articles by Gross, R Search for Related Content PubMed PubMed Citation Articles by Carbonetti, N H Articles by Gross, R

 Previous Article  |  Next Article 

J Bacteriol. 1994 December; 176(23): 7267-7273

research-article

Effect of mutations causing overexpression of RNA polymerase alpha subunit on regulation of virulence factors in Bordetella pertussis.

Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore 21201.

ABSTRACT

In Bordetella pertussis, expression of virulence factors is controlled by the Bvg proteins, which comprise a sensor-regulator two-component signal transduction system. Previously, we described a mutant strain of B. pertussis that had reduced transcription of pertussis toxin and adenylate cyclase toxin genes, while other virulence factors were relatively unaffected. We obtained a B. pertussis clone that repaired the defect in both this strain and an independent mutant strain with a similar phenotype when introduced onto the chromosome by allelic exchange. Further analysis revealed that the mutations were just upstream of the translational start site of the rpoA gene encoding the alpha subunit of RNA polymerase. We confirmed that these mutations were responsible for the mutant phenotype by site-directed mutagenesis. Our hypothesis that these mutations cause an overexpression of rpoA was confirmed by Western immunoblotting and translational fusion analysis. Corroboration of this effect was obtained by overexpressing rpoA on a plasmid in wild-type B. pertussis, which caused the same phenotype as the mutants showed. Conclusions in regard to the identity of the transcription activator of the toxin genes are discussed.

This article has been cited by other articles:

• Stubs, D., Fuchs, T. M., Schneider, B., Bosserhoff, A., Gross, R. (2005). Identification and regulation of cold-inducible factors of Bordetella bronchiseptica. Microbiology 151: 1895-1909 [Abstract] [Full Text]  
• Peck, M. C., Gaal, T., Fisher, R. F., Gourse, R. L., Long, S. R. (2002). The RNA Polymerase {alpha} Subunit from Sinorhizobium meliloti Can Assemble with RNA Polymerase Subunits from Escherichia coli and Function in Basal and Activated Transcription both In Vivo and In Vitro. J. Bacteriol. 184: 3808-3814 [Abstract] [Full Text]  
• Kinnear, S. M., Marques, R. R., Carbonetti, N. H. (2001). Differential Regulation of Bvg-Activated Virulence Factors Plays a Role in Bordetella pertussis Pathogenicity. Infect. Immun. 69: 1983-1993 [Abstract] [Full Text]  
• Carbonetti, N. H., Romashko, A., Irish, T. J. (2000). Overexpression of the RNA Polymerase Alpha Subunit Reduces Transcription of Bvg-Activated Virulence Genes in Bordetella pertussis. J. Bacteriol. 182: 529-531 [Abstract] [Full Text]  
• Kinnear, S. M., Boucher, P. E., Stibitz, S., Carbonetti, N. H. (1999). Analysis of BvgA Activation of the Pertactin Gene Promoter in Bordetella pertussis. J. Bacteriol. 181: 5234-5241 [Abstract] [Full Text]  
• Stibitz, S. (1998). Mutations Affecting the alpha  Subunit of Bordetella pertussis RNA Polymerase Suppress Growth Inhibition Conferred by Short C-Terminal Deletions of the Response Regulator BvgA. J. Bacteriol. 180: 2484-2492 [Abstract] [Full Text]  
• Steffen, P., Ullmann, A. (1998). Hybrid Bordetella pertussis-Escherichia coli RNA Polymerases: Selectivity of Promoter Activation. J. Bacteriol. 180: 1567-1569 [Abstract] [Full Text]