PMID:16491026

From EcoliWiki
Jump to navigation Jump to search
Citation

Flores, S, Flores, N, de Anda, R, González, A, Escalante, A, Sigala, JC, Gosset, G and Bolívar, F (2005) Nutrient-scavenging stress response in an Escherichia coli strain lacking the phosphoenolpyruvate: carbohydrate phosphotransferase system, as explored by gene expression profile analysis. J. Mol. Microbiol. Biotechnol. 10:51-63

Abstract

The physiological role of the phosphoenolpyruvate:carbohydrate phosphotransferase system (PTS) has been studied in Escherichia coli. It has been shown that it directly or indirectly regulates the activity of most catabolic genes involved in carbohydrate transport. Accordingly, strains lacking PTS have pleiotropic phenotypes and are impaired in their capacity to grow on glucose and other PTS sugars. We have previously reported the characterization of a mutant harboring a pts operon deletion (PB11) which, as expected, showed a severe reduction of its growth capacity when incubated on glucose as carbon source, as compared to that of the isogenic wild-type strain. These observations corroborate that PTS is the main determinant of the capacity to grow on glucose and confirm the existence of other systems that allow glucose utilization although at a reduced level. To explore the physiological state and the metabolic pathways involved in glucose utilization in a pts(-) background, we analyzed the global transcriptional response of the PB11 mutant when growing in minimal medium with glucose as carbon source. Genome-wide transcriptional analysis using microarrays revealed that, under this condition, expression of several genes related to carbon transport and metabolism was upregulated, as well as that of genes encoding transporters for certain nucleotides, nitrogen, phosphorus and sulfur sources. In addition, upregulation of rpoS and several genes transcribed by this sigma subunit was detected. These results indicate that the reduced capacity of glucose utilization present in the PB11 strain induces a general nutrient-scavenging response and this behavior is not dependent on a functional PTS. This condition is responsible of the utilization of secondary carbon sources in the presence of glucose.

Links

PubMed Online version:10.1159/000090348

Keywords

Biological Transport; Carbohydrate Metabolism; Escherichia coli/genetics; Escherichia coli/metabolism; Escherichia coli/physiology; Escherichia coli Proteins/biosynthesis; Escherichia coli Proteins/genetics; Gene Expression Profiling; Gene Expression Regulation, Bacterial; Glucose/metabolism; Mutation; Operon; Phosphoenolpyruvate/metabolism; Phosphoenolpyruvate Sugar Phosphotransferase System/physiology; Sigma Factor/biosynthesis

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.