PMID:11032803

From EcoliWiki
Jump to navigation Jump to search
Citation

Lee, SJ, Boos, W, Bouché, JP and Plumbridge, J (2000) Signal transduction between a membrane-bound transporter, PtsG, and a soluble transcription factor, Mlc, of Escherichia coli. EMBO J. 19:5353-61

Abstract

The global regulator Mlc controls several genes implicated in sugar utilization systems, notably the phosphotransferase system (PTS) genes, ptsG, manXYZ and ptsHI, as well as the malT activator. No specific low molecular weight inducer has been identified that can inactivate Mlc, but its activity appeared to be modulated by transport of glucose via Enzyme IICB(Glc) (PtsG). Here we demonstrate that inactivation of Mlc is achieved by sequestration of Mlc to membranes containing dephosphorylated Enzyme IICB(Glc). We show that Mlc binds specifically to membrane fractions which carry PtsG and that excess Mlc can inhibit Enzyme IICB(Glc) phosphorylation by the general PTS proteins and also Enzyme IICB(Glc)-mediated phosphorylation of alpha-methylglucoside. Binding of Mlc to Enzyme IICB(Glc) in vitro required the IIB domain and the IIC-B junction region. Moreover, we show that these same regions are sufficient for Mlc regulation in vivo, via cross-dephosphorylation of IIB(Glc) during transport of other PTS sugars. The control of Mlc activity by sequestration to a transport protein represents a novel form of signal transduction in gene regulation.

Links

PubMed PMC313994 Online version:10.1093/emboj/19.20.5353

Keywords

Bacterial Proteins/metabolism; Binding Sites; Cell Membrane/metabolism; DNA, Bacterial/genetics; DNA, Bacterial/metabolism; DNA-Binding Proteins/metabolism; Escherichia coli/drug effects; Escherichia coli/enzymology; Escherichia coli/genetics; Escherichia coli/metabolism; Escherichia coli Proteins; Gene Expression Regulation, Bacterial; Genes, Reporter; Membrane Proteins/genetics; Membrane Proteins/metabolism; Methylglucosides/metabolism; Models, Biological; Mutation; Operator Regions, Genetic/genetics; Phosphoenolpyruvate Sugar Phosphotransferase System/genetics; Phosphoenolpyruvate Sugar Phosphotransferase System/metabolism; Phosphorylation/drug effects; Protein Binding; Protein Structure, Tertiary; Repressor Proteins/metabolism; Signal Transduction; Solubility; Transcription Factors/metabolism

Significance

You can help EcoliWiki by summarizing why this paper is useful

Useful Materials and Methods

You can help Ecoliwiki by describing the useful materials (strains, plasmids, antibodies, etc) described in this paper.

Annotations

<annotationlinks/>

EcoliWiki Links

Add links to pages that link here (e.g. gene, product, method pages)

References

See Help:References for how to manage references in EcoliWiki.