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 Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Sirko, A Articles by Sawers, G Search for Related Content PubMed PubMed Citation Articles by Sirko, A Articles by Sawers, G

research-article

Integration host factor is required for anaerobic pyruvate induction of pfl operon expression in Escherichia coli.

Department of Biochemistry, State University of New York at Stony Brook 11794.

ABSTRACT

The expression of the pyruvate formate-lyase gene (pfl) is induced by anaerobic growth, and this is increased further by growth in pyruvate. Previous work has shown that anaerobic induction is strongly dependent on the activator FNR and partially dependent on a second transcription factor, ArcA, while pyruvate induction only required FNR. Anaerobic and pyruvate regulation both require the presence of a 5' nontranslated regulatory sequence which spans approximately 500 bp of DNA. A mobility shift assay was developed to identify proteins that bind to this regulatory region. Several binding activities were separated by heparin agarose chromatography, and one of these activities was characterized and shown to be integration host factor (IHF). Mobility shift and DNase I footprinting experiments defined a single IHF binding site in the pfl promoter-regulatory region. With pfl-lacZ fusions, it could be shown that introduction of a himD mutation abolished pyruvate-dependent induction of anaerobic expression in vivo. The same result was observed when the pfl IHF binding site was mutated. In addition, the partial anaerobic induction of expression found in an fnr strain was completely blocked in an fnr himD double mutant and in an fnr IHF binding site double mutant. Taken together, these data suggest that IHF is necessary for both pyruvate induction and the anaerobic induction mediated by ArcA.

This article has been cited by other articles:

• Mettert, E. L., Kiley, P. J. (2007). Contributions of [4Fe-4S]-FNR and Integration Host Factor to fnr Transcriptional Regulation. J. Bacteriol. 189: 3036-3043 [Abstract] [Full Text]  
• Aeling, K. A., Opel, M. L., Steffen, N. R., Tretyachenko-Ladokhina, V., Hatfield, G. W., Lathrop, R. H., Senear, D. F. (2006). Indirect Recognition in Sequence-specific DNA Binding by Escherichia coli Integration Host Factor: THE ROLE OF DNA DEFORMATION ENERGY. J. Biol. Chem. 281: 39236-39248 [Abstract] [Full Text]  
• Sawers, R. G. (2005). Expression of fnr Is Constrained by an Upstream IS5 Insertion in Certain Escherichia coli K-12 Strains. J. Bacteriol. 187: 2609-2617 [Abstract] [Full Text]  
• Salgado, H., Santos-Zavaleta, A., Gama-Castro, S., Millan-Zarate, D., Blattner, F. R., Collado-Vides, J. (2000). RegulonDB (version 3.0): transcriptional regulation and operon organization in Escherichia coli K-12. Nucleic Acids Res 28: 65-67 [Abstract] [Full Text]  
• van der Ploeg, J. R., Iwanicka-Nowicka, R., Bykowski, T., Hryniewicz, M. M., Leisinger, T. (1999). The Escherichia coli ssuEADCB Gene Cluster Is Required for the Utilization of Sulfur from Aliphatic Sulfonates and Is Regulated by the Transcriptional Activator Cbl. J. Biol. Chem. 274: 29358-29365 [Abstract] [Full Text]  
• Brinkman, A. B., Dahlke, I., Tuininga, J. E., Lammers, T., Dumay, V., de Heus, E., Lebbink, J. H. G., Thomm, M., de Vos, W. M., van der Oost, J. (2000). An Lrp-like Transcriptional Regulator from the Archaeon Pyrococcus furiosus Is Negatively Autoregulated. J. Biol. Chem. 275: 38160-38169 [Abstract] [Full Text]