Differential regulation of high-affinity phosphate transport systems of Mycobacterium smegmatis:: Identification of PhnF, a repressor of the phnDCE operon

Abstract

ABSTRACT The uptake of phosphate into the cell via high-affinity, phosphate-specific transport systems has been studied with several species of mycobacteria. All of these species have been shown to contain several copies of such transport systems, which are synthesized in response to phosphate limitation. However, the mechanisms leading to the expression of the genes encoding these transporters have not been studied. This study reports on the investigation of the regulation of the pstSCAB and the phnDCE operons of Mycobacterium smegmatis . The phn locus contains an additional gene, phnF , encoding a GntR-like transcriptional regulator. Expression analyses of a phnF deletion mutant demonstrated that PhnF acts as a repressor of the phnDCE operon but does not affect the expression of pstSCAB . The deletion of pstS , which is thought to cause the constitutive expression of genes regulated by the two-component system SenX3-RegX3, led to the constitutive expression of the transcriptional fusions pstS - lacZ, phnD - lacZ , and phnF - lacZ , suggesting that phnDCE and phnF are conceivably new members of the SenX3-RegX3 regulon of M. smegmatis . Two presumptive binding sites for PhnF in the intergenic region between phnD and phnF were identified and shown to be required for the repression of phnD and phnF , respectively. We propose a model in which the transcription of pstSCAB is controlled by the two-component SenX3-RegX3 system, while phnDCE and phnF are subject to dual control by SenX3-RegX3 and PhnF.

Autoren

Susanne Gebhard
Gregory M Cook

DOI

10.1128/jb.01764-07

eISSN

1098-5530

ISSN

0021-9193

Ausgabe der Veröffentlichung

4

Zeitschrift

Journal of Bacteriology

Sprache

en

Paginierung

1335 - 1343

Datum der Veröffentlichung

2008

Status

Published

Herausgeber

American Society for Microbiology

Herausgeber URL

http://dx.doi.org/10.1128/jb.01764-07

Datum der Datenerfassung

2021

Titel

Differential Regulation of High-Affinity Phosphate Transport Systems of <i>Mycobacterium smegmatis</i> : Identification of PhnF, a Repressor of the <i>phnDCE</i> Operon

Ausgabe der Zeitschrift

190

Data source: Crossref

Abstract

The uptake of phosphate into the cell via high-affinity, phosphate-specific transport systems has been studied with several species of mycobacteria. All of these species have been shown to contain several copies of such transport systems, which are synthesized in response to phosphate limitation. However, the mechanisms leading to the expression of the genes encoding these transporters have not been studied. This study reports on the investigation of the regulation of the pstSCAB and the phnDCE operons of Mycobacterium smegmatis. The phn locus contains an additional gene, phnF, encoding a GntR-like transcriptional regulator. Expression analyses of a phnF deletion mutant demonstrated that PhnF acts as a repressor of the phnDCE operon but does not affect the expression of pstSCAB. The deletion of pstS, which is thought to cause the constitutive expression of genes regulated by the two-component system SenX3-RegX3, led to the constitutive expression of the transcriptional fusions pstS-lacZ, phnD-lacZ, and phnF-lacZ, suggesting that phnDCE and phnF are conceivably new members of the SenX3-RegX3 regulon of M. smegmatis. Two presumptive binding sites for PhnF in the intergenic region between phnD and phnF were identified and shown to be required for the repression of phnD and phnF, respectively. We propose a model in which the transcription of pstSCAB is controlled by the two-component SenX3-RegX3 system, while phnDCE and phnF are subject to dual control by SenX3-RegX3 and PhnF.

Addresses

Department of Microbiology and Immunology, Otago School of Medical Sciences, University of Otago, P.O. Box 56, Dunedin, New Zealand.

Autoren

Susanne Gebhard
Gregory M Cook

DOI

10.1128/jb.01764-07

eISSN

1098-5530

Externe Identifier

PubMed Identifier: 18083811
PubMed Central ID: PMC2238217

Open access

false

ISSN

0021-9193

Ausgabe der Veröffentlichung

4

Zeitschrift

Journal of bacteriology

Schlüsselwörter

Mycobacterium smegmatis
Phosphates
Bacterial Proteins
Recombinant Fusion Proteins
Mutagenesis, Site-Directed
Sequence Analysis, DNA
Transcription, Genetic
Gene Expression Regulation, Bacterial
Sequence Deletion
Binding Sites
Base Sequence
Protein Binding
Operon
Lac Operon
Regulon
Models, Biological
Models, Genetic

Sprache

eng

Medium

Print-Electronic

Online publication date

2007

Paginierung

1335 - 1343

Datum der Veröffentlichung

2008

Status

Published

Datum der Datenerfassung

2007

Titel

Differential regulation of high-affinity phosphate transport systems of Mycobacterium smegmatis: identification of PhnF, a repressor of the phnDCE operon.

Sub types

Research Support, Non-U.S. Gov't
research-article
Journal Article

Ausgabe der Zeitschrift

190

Files

https://europepmc.org/articles/pmc2238217?pdf=render

Data source: Europe PubMed Central

Abstract

The uptake of phosphate into the cell via high-affinity, phosphate-specific transport systems has been studied with several species of mycobacteria. All of these species have been shown to contain several copies of such transport systems, which are synthesized in response to phosphate limitation. However, the mechanisms leading to the expression of the genes encoding these transporters have not been studied. This study reports on the investigation of the regulation of the pstSCAB and the phnDCE operons of Mycobacterium smegmatis. The phn locus contains an additional gene, phnF, encoding a GntR-like transcriptional regulator. Expression analyses of a phnF deletion mutant demonstrated that PhnF acts as a repressor of the phnDCE operon but does not affect the expression of pstSCAB. The deletion of pstS, which is thought to cause the constitutive expression of genes regulated by the two-component system SenX3-RegX3, led to the constitutive expression of the transcriptional fusions pstS-lacZ, phnD-lacZ, and phnF-lacZ, suggesting that phnDCE and phnF are conceivably new members of the SenX3-RegX3 regulon of M. smegmatis. Two presumptive binding sites for PhnF in the intergenic region between phnD and phnF were identified and shown to be required for the repression of phnD and phnF, respectively. We propose a model in which the transcription of pstSCAB is controlled by the two-component SenX3-RegX3 system, while phnDCE and phnF are subject to dual control by SenX3-RegX3 and PhnF.

Autoren

Susanne Gebhard
Gregory M Cook

Autoren-URL

https://www.ncbi.nlm.nih.gov/pubmed/18083811

DOI

10.1128/JB.01764-07

eISSN

1098-5530

Externe Identifier

PubMed Central ID: PMC2238217

Ausgabe der Veröffentlichung

4

Zeitschrift

J Bacteriol

Schlüsselwörter

Bacterial Proteins
Base Sequence
Binding Sites
Gene Expression Regulation, Bacterial
Lac Operon
Models, Biological
Models, Genetic
Mutagenesis, Site-Directed
Mycobacterium smegmatis
Operon
Phosphates
Protein Binding
Recombinant Fusion Proteins
Regulon
Sequence Analysis, DNA
Sequence Deletion
Transcription, Genetic

Sprache

eng

Country

United States

Paginierung

1335 - 1343

PII

JB.01764-07

Datum der Veröffentlichung

2008

Status

Published

Datum, an dem der Datensatz öffentlich gemacht wurde

2008

Titel

Differential regulation of high-affinity phosphate transport systems of Mycobacterium smegmatis: identification of PhnF, a repressor of the phnDCE operon.

Sub types

Journal Article
Research Support, Non-U.S. Gov't

Ausgabe der Zeitschrift

190

Data source: PubMed

Differential regulation of high-affinity phosphate transport systems of Mycobacterium smegmatis:: Identification of PhnF, a repressor of the phnDCE operon

Files

Tools