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 Wilson, R L Articles by Stauffer, G V Search for Related Content PubMed PubMed Citation Articles by Wilson, R L Articles by Stauffer, G V

research-article

Roles of the GcvA and PurR proteins in negative regulation of the Escherichia coli glycine cleavage enzyme system.

Department of Microbiology, University of Iowa, Iowa City 52242.

ABSTRACT

When Escherichia coli was grown in medium containing both inosine and glycine, the PurR repressor protein was shown to be responsible for a twofold reduction from the fully induced glycine cleavage enzyme levels. This twofold repression was also seen by measuring beta-galactosidase levels in cells carrying a lambda gcvT-lacZ gene fusion. In this fusion, the synthesis of beta-galactosidase is under the control of the gcv regulatory region. A DNA fragment carrying the gcv control region was shown by gel mobility shift assay and DNase I footprinting to bind purified PurR protein, suggesting a direct involvement of the repressor in gcv regulation. A separate mechanism of purine-mediated regulation of gcv was shown to be independent of the purR gene product and resulted in an approximately 10-fold reduction of beta-galactosidase levels when cells were grown in medium containing inosine but lacking the inducer glycine. This additional repression was dependent upon a functional gcvA gene, a positive activator for the glycine cleavage enzyme system. A dual role for the GcvA protein as both an activator in the presence of glycine and a repressor in the presence of inosine is suggested.

This article has been cited by other articles:

• Mukherjee, M., Brown, M. T., McArthur, A. G., Johnson, P. J. (2006). Proteins of the Glycine Decarboxylase Complex in the Hydrogenosome of Trichomonas vaginalis. Eukaryot Cell 5: 2062-2071 [Abstract] [Full Text]  
• Bauwe, H., Kolukisaoglu, U. (2003). Genetic manipulation of glycine decarboxylation. J Exp Bot 54: 1523-1535 [Abstract] [Full Text]  
• Li, R., Moore, M., King, J. (2003). Investigating the Regulation of One-carbon Metabolism in Arabidopsis thaliana. Plant Cell Physiol 44: 233-241 [Abstract] [Full Text]  
• Pruss, B. M., Campbell, J. W., Van Dyk, T. K., Zhu, C., Kogan, Y., Matsumura, P. (2003). FlhD/FlhC Is a Regulator of Anaerobic Respiration and the Entner-Doudoroff Pathway through Induction of the Methyl-Accepting Chemotaxis Protein Aer. J. Bacteriol. 185: 534-543 [Abstract] [Full Text]  
• Heil, G., Stauffer, L. T., Stauffer, G. V. (2002). Glycine binds the transcriptional accessory protein GcvR to disrupt a GcvA/GcvR interaction and allow GcvA-mediated activation of the Escherichia coli gcvTHP operon. Microbiology 148: 2203-2214 [Abstract] [Full Text]  
• Ghrist, A. C., Heil, G., Stauffer, G. V. (2001). GcvR interacts with GcvA to inhibit activation of the Escherichia coli glycine cleavage operon. Microbiology 147: 2215-2221 [Abstract] [Full Text]  
• Wonderling, L. D., Urbanowski, M. L., Stauffer, G. V. (2000). GcvA binding site 1 in the gcvTHP promoter of Escherichia coli is required for GcvA-mediated repression but not for GcvA-mediated activation. Microbiology 146: 2909-2918 [Abstract] [Full Text]  
• Wonderling, L. D., Stauffer, G. V. (1999). The Cyclic AMP Receptor Protein Is Dependent on GcvA for Regulation of the gcv Operon. J. Bacteriol. 181: 1912-1919 [Abstract] [Full Text]  
• Jourdan, A. D., Stauffer, G. V. (1998). Mutational Analysis of the Transcriptional Regulator GcvA: Amino Acids Important for Activation, Repression, and DNA Binding. J. Bacteriol. 180: 4865-4871 [Abstract] [Full Text]  
• Berlyn, M. K. B. (1998). Linkage Map of Escherichia coli K-12, Edition 10: The Traditional Map. Microbiol. Mol. Biol. Rev. 62: 814-984 [Abstract] [Full Text]  
• Xu, H., Moraitis, M., Reedstrom, R. J., Matthews, K. S. (1998). Kinetic and Thermodynamic Studies of Purine Repressor Binding to Corepressor and Operator DNA. J. Biol. Chem. 273: 8958-8964 [Abstract] [Full Text]  
• Ghrist, A. C., Stauffer, G. V. (1998). Promoter Characterization and Constitutive Expression of the Escherichia coli gcvR Gene. J. Bacteriol. 180: 1803-1807 [Abstract] [Full Text]