O-antigen expression in Salmonella enterica serovar Typhi is regulated by nitrogen availability through RpoN-mediated transcriptional control of the rfaH gene

Mauricio Bittner, Soledad Saldías, Claudia Estévez, Mercedes Zaldívar, Cristina L. Marolda, Miguel A. Valvano, Inés Contreras

Resultado de la investigación: Review article

19 Citas (Scopus)

Resumen

The authors previously reported increased expression of the Salmonella enterica serovar Typhi (S. typhi) rfaH gene when the bacterial cells reach stationary phase. In this study, using a lacZ fusion to the rfaH promoter region, they demonstrate that growth-dependent regulation of rfaH expression occurs at the level of transcription initiation. It was also observed that production of the lipopolysaccharide (LPS) O-antigen by S. typhi Ty2 correlated with the differential expression of rfaH during bacterial growth. This was probably due to the increased cellular levels of RfaH, since expression of the distal gene in the O-antigen gene cluster of S. typhi Ty2, wbaP, was also increased during stationary growth, as demonstrated by RT-PCR analysis. Examination of the sequences upstream of the rfaH coding region revealed homologies to potential binding sites for the RcsB/RcsA dimer of the RcsC/YopJ/RcsB phosphorelay regulatory system and for the RpoN alternative sigma factor. The expression of the rfaH gene in rpoN and rcsB mutants of S. typhi Ty2 was measured. The results indicate that inactivation of rpoN, but not of rcsB, suppresses the growth-phase-dependent induction of rfaH expression. Furthermore, production of β-galactosidase mediated by the rfAH-lacZ fusion increased approximately fourfold when bacteria were grown in a nitrogen-limited medium. Nitrogen limitation was also shown to increase the expression of the O-antigen by the wild-type S. typhi Ty2, as demonstrated by a similar electrophoretic profile to that observed during the stationary phase of growth in rich media. It is therefore concluded that the relationship between LPS production and nitrogen limitation parallels the pattern of rfaH regulation under the control of RpoN and is consistent with the idea that RpoN modulates LPS formation via its effect on rfaH gene expression during bacterial growth.

Idioma originalEnglish
Páginas (desde-hasta)3789-3799
Número de páginas11
PublicaciónMicrobiology
Volumen148
N.º12
EstadoPublished - 1 dic 2002

Huella dactilar

O Antigens
Salmonella typhi
Nitrogen
Growth
Genes
Lipopolysaccharides
Gene Expression
Galactosidases
Sigma Factor
Bacterial Genes
Multigene Family
Genetic Promoter Regions
Binding Sites
Bacteria
Polymerase Chain Reaction
Serogroup

ASJC Scopus subject areas

  • Microbiology

Citar esto

Bittner, M., Saldías, S., Estévez, C., Zaldívar, M., Marolda, C. L., Valvano, M. A., & Contreras, I. (2002). O-antigen expression in Salmonella enterica serovar Typhi is regulated by nitrogen availability through RpoN-mediated transcriptional control of the rfaH gene. Microbiology, 148(12), 3789-3799.
Bittner, Mauricio ; Saldías, Soledad ; Estévez, Claudia ; Zaldívar, Mercedes ; Marolda, Cristina L. ; Valvano, Miguel A. ; Contreras, Inés. / O-antigen expression in Salmonella enterica serovar Typhi is regulated by nitrogen availability through RpoN-mediated transcriptional control of the rfaH gene. En: Microbiology. 2002 ; Vol. 148, N.º 12. pp. 3789-3799.
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abstract = "The authors previously reported increased expression of the Salmonella enterica serovar Typhi (S. typhi) rfaH gene when the bacterial cells reach stationary phase. In this study, using a lacZ fusion to the rfaH promoter region, they demonstrate that growth-dependent regulation of rfaH expression occurs at the level of transcription initiation. It was also observed that production of the lipopolysaccharide (LPS) O-antigen by S. typhi Ty2 correlated with the differential expression of rfaH during bacterial growth. This was probably due to the increased cellular levels of RfaH, since expression of the distal gene in the O-antigen gene cluster of S. typhi Ty2, wbaP, was also increased during stationary growth, as demonstrated by RT-PCR analysis. Examination of the sequences upstream of the rfaH coding region revealed homologies to potential binding sites for the RcsB/RcsA dimer of the RcsC/YopJ/RcsB phosphorelay regulatory system and for the RpoN alternative sigma factor. The expression of the rfaH gene in rpoN and rcsB mutants of S. typhi Ty2 was measured. The results indicate that inactivation of rpoN, but not of rcsB, suppresses the growth-phase-dependent induction of rfaH expression. Furthermore, production of β-galactosidase mediated by the rfAH-lacZ fusion increased approximately fourfold when bacteria were grown in a nitrogen-limited medium. Nitrogen limitation was also shown to increase the expression of the O-antigen by the wild-type S. typhi Ty2, as demonstrated by a similar electrophoretic profile to that observed during the stationary phase of growth in rich media. It is therefore concluded that the relationship between LPS production and nitrogen limitation parallels the pattern of rfaH regulation under the control of RpoN and is consistent with the idea that RpoN modulates LPS formation via its effect on rfaH gene expression during bacterial growth.",
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Bittner, M, Saldías, S, Estévez, C, Zaldívar, M, Marolda, CL, Valvano, MA & Contreras, I 2002, 'O-antigen expression in Salmonella enterica serovar Typhi is regulated by nitrogen availability through RpoN-mediated transcriptional control of the rfaH gene', Microbiology, vol. 148, n.º 12, pp. 3789-3799.

O-antigen expression in Salmonella enterica serovar Typhi is regulated by nitrogen availability through RpoN-mediated transcriptional control of the rfaH gene. / Bittner, Mauricio; Saldías, Soledad; Estévez, Claudia; Zaldívar, Mercedes; Marolda, Cristina L.; Valvano, Miguel A.; Contreras, Inés.

En: Microbiology, Vol. 148, N.º 12, 01.12.2002, p. 3789-3799.

Resultado de la investigación: Review article

TY - JOUR

T1 - O-antigen expression in Salmonella enterica serovar Typhi is regulated by nitrogen availability through RpoN-mediated transcriptional control of the rfaH gene

AU - Bittner, Mauricio

AU - Saldías, Soledad

AU - Estévez, Claudia

AU - Zaldívar, Mercedes

AU - Marolda, Cristina L.

AU - Valvano, Miguel A.

AU - Contreras, Inés

PY - 2002/12/1

Y1 - 2002/12/1

N2 - The authors previously reported increased expression of the Salmonella enterica serovar Typhi (S. typhi) rfaH gene when the bacterial cells reach stationary phase. In this study, using a lacZ fusion to the rfaH promoter region, they demonstrate that growth-dependent regulation of rfaH expression occurs at the level of transcription initiation. It was also observed that production of the lipopolysaccharide (LPS) O-antigen by S. typhi Ty2 correlated with the differential expression of rfaH during bacterial growth. This was probably due to the increased cellular levels of RfaH, since expression of the distal gene in the O-antigen gene cluster of S. typhi Ty2, wbaP, was also increased during stationary growth, as demonstrated by RT-PCR analysis. Examination of the sequences upstream of the rfaH coding region revealed homologies to potential binding sites for the RcsB/RcsA dimer of the RcsC/YopJ/RcsB phosphorelay regulatory system and for the RpoN alternative sigma factor. The expression of the rfaH gene in rpoN and rcsB mutants of S. typhi Ty2 was measured. The results indicate that inactivation of rpoN, but not of rcsB, suppresses the growth-phase-dependent induction of rfaH expression. Furthermore, production of β-galactosidase mediated by the rfAH-lacZ fusion increased approximately fourfold when bacteria were grown in a nitrogen-limited medium. Nitrogen limitation was also shown to increase the expression of the O-antigen by the wild-type S. typhi Ty2, as demonstrated by a similar electrophoretic profile to that observed during the stationary phase of growth in rich media. It is therefore concluded that the relationship between LPS production and nitrogen limitation parallels the pattern of rfaH regulation under the control of RpoN and is consistent with the idea that RpoN modulates LPS formation via its effect on rfaH gene expression during bacterial growth.

AB - The authors previously reported increased expression of the Salmonella enterica serovar Typhi (S. typhi) rfaH gene when the bacterial cells reach stationary phase. In this study, using a lacZ fusion to the rfaH promoter region, they demonstrate that growth-dependent regulation of rfaH expression occurs at the level of transcription initiation. It was also observed that production of the lipopolysaccharide (LPS) O-antigen by S. typhi Ty2 correlated with the differential expression of rfaH during bacterial growth. This was probably due to the increased cellular levels of RfaH, since expression of the distal gene in the O-antigen gene cluster of S. typhi Ty2, wbaP, was also increased during stationary growth, as demonstrated by RT-PCR analysis. Examination of the sequences upstream of the rfaH coding region revealed homologies to potential binding sites for the RcsB/RcsA dimer of the RcsC/YopJ/RcsB phosphorelay regulatory system and for the RpoN alternative sigma factor. The expression of the rfaH gene in rpoN and rcsB mutants of S. typhi Ty2 was measured. The results indicate that inactivation of rpoN, but not of rcsB, suppresses the growth-phase-dependent induction of rfaH expression. Furthermore, production of β-galactosidase mediated by the rfAH-lacZ fusion increased approximately fourfold when bacteria were grown in a nitrogen-limited medium. Nitrogen limitation was also shown to increase the expression of the O-antigen by the wild-type S. typhi Ty2, as demonstrated by a similar electrophoretic profile to that observed during the stationary phase of growth in rich media. It is therefore concluded that the relationship between LPS production and nitrogen limitation parallels the pattern of rfaH regulation under the control of RpoN and is consistent with the idea that RpoN modulates LPS formation via its effect on rfaH gene expression during bacterial growth.

KW - Lipopolysaccharide

KW - Regulation

KW - Sigma factor

KW - Transcription

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M3 - Review article

VL - 148

SP - 3789

EP - 3799

JO - Microbiology (United Kingdom)

JF - Microbiology (United Kingdom)

SN - 1350-0872

IS - 12

ER -