RpoS and RpoN are involved in the growth-dependent regulation of rfaH transcription and O antigen expression in Salmonella enterica serovar typhi
We reported earlier that the production of O antigen lipopolysaccharide (LPS) by Salmonella enterica serovar Typhi ( Salmonella typhi) increases at the onset of stationary phase and correlates with a growth-regulated expression of the rfaH gene under the control of the alternative sigma factor RpoN...
Gespeichert in:
Veröffentlicht in: | Microbial pathogenesis 2004, Vol.36 (1), p.19-24 |
---|---|
Hauptverfasser: | , , , , |
Format: | Artikel |
Sprache: | eng |
Schlagworte: | |
Online-Zugang: | Volltext |
Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
Zusammenfassung: | We reported earlier that the production of O antigen lipopolysaccharide (LPS) by
Salmonella enterica serovar Typhi (
Salmonella typhi) increases at the onset of stationary phase and correlates with a growth-regulated expression of the
rfaH gene under the control of the alternative sigma factor RpoN (Microbiology 148 (2002) 3789). In this study, we demonstrate that RpoS also modulates
rfaH promoter activity as revealed by the absence of growth-dependent regulation of an
rfaH–
lacZ transcriptional fusion and O antigen production in a
S. typhi rpoS mutant. Introduction of a constitutively expressed
rpoN gene into the
rpoS mutant restored increased production of O antigen during stationary phase, suggesting that constitutive production of RpoN could overcome the RpoS defect. Similar results were observed when an
rpoS rpoN double mutant was transformed with the intact
rpoN gene. Thus, we conclude that both RpoS and RpoN control the
rfaH promoter activity and concomitantly, the production of O-specific LPS in
S. typhi. |
---|---|
ISSN: | 0882-4010 1096-1208 |
DOI: | 10.1016/j.micpath.2003.08.003 |