The relation between ppGpp and the PHO regulon in Escherichia coli

Starving of Escherichia coli cells for inorganic orthophosphate (Pi) results in the accumulation of spoT-dependent ppGpp and induces the expression of genes of the PHO regulon. In a delta relA delta spoT strain that is unable to accumulate ppGpp the expression of two genes (phoA and pstS) that belon...

Full description

Saved in:
Bibliographic Details
Published in:Molecular & general genetics 1998-02, Vol.257 (4), p.469-477
Main Authors: Spira, B, Yagil, E
Format: Article
Language:English
Subjects:
Alkaline Phosphatase - biosynthesis
Alkaline Phosphatase - genetics
Bacterial Proteins - biosynthesis
Bacterial Proteins - genetics
Carrier Proteins - biosynthesis
Carrier Proteins - genetics
Escherichia coli - genetics
Escherichia coli Proteins
Gene Expression Regulation, Bacterial
Guanosine Tetraphosphate - physiology
Membrane Proteins - biosynthesis
Membrane Proteins - genetics
Periplasmic Binding Proteins
Phosphate-Binding Proteins
Phosphates - metabolism
Phosphates - pharmacology
Regulon - genetics
Transcription, Genetic
Citations: Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Starving of Escherichia coli cells for inorganic orthophosphate (Pi) results in the accumulation of spoT-dependent ppGpp and induces the expression of genes of the PHO regulon. In a delta relA delta spoT strain that is unable to accumulate ppGpp the expression of two genes (phoA and pstS) that belong to the PHO regulon is impaired, even in constitutive mutants. The transcription of phoA and of pstS is not affected in the ppGpp0 strain, and therefore this impairment is due to a post-transcriptional defect. Conversely, overexpression of ppGpp inhibits transcription of these two PHO regulon genes. In phoB mutants, the accumulation of ppGpp during Pi starvation is diminished, suggesting that PhoB or one of the PHO products is involved in the control of ppGpp accumulation. We propose that the presence of ppGpp in the cell, but not its accumulation as a result of the starvation stress, is important for the expression of the PHO genes.
ISSN:0026-8925
1432-1874
DOI:10.1007/s004380050671