Pyrimidine Regulation of theEscherichia coliandSalmonella typhimurium carABOperons: CarP and Integration Host Factor (IHF) Modulate the Methylation Status of a GATC Site Present in the Control Region

1995 ◽  
Vol 250 (4) ◽  
pp. 383-391 ◽  
Author(s):  
Daniel Charlier ◽  
Daniel Gigot ◽  
Nadine Huysveld ◽  
Martine Roovers ◽  
André Piérard ◽  
...  
Keyword(s):  
Control Region ◽  
Methylation Status ◽  
Integration Host Factor ◽  
Host Factor ◽  
Gatc Site

scholarly journals Mutational Analysis of Intervening Sequences Connecting the Binding Sites for Integration Host Factor, PepA, PurR, and RNA Polymerase in the Control Region of the Escherichia coli carAB Operon, Encoding Carbamoylphosphate Synthase

2006 ◽  
Vol 188 (9) ◽  
pp. 3236-3245 ◽  
Author(s):  
Neel Devroede ◽  
Nadine Huysveld ◽  
Daniel Charlier
Keyword(s):  
Escherichia Coli ◽  
Rna Polymerase ◽  
Control Region ◽  
Binding Sites ◽  
Mutational Analysis ◽  
Integration Host Factor ◽  
Host Factor ◽  
Dual Function ◽  
Pyrimidine Nucleotides ◽  
Upstream Promoter

ABSTRACT Transcription of the carAB operon encoding the unique carbamoylphosphate synthase of Escherichia coli reflects the dual function of carbamoylphosphate in the biosynthesis of arginine and pyrimidine nucleotides. The tandem pair of promoters is regulated by various mechanisms depending on the needs of both pathways and the maintenance of a pyrimidine/purine nucleotide balance. Here we focus on the linker regions that impose the distribution of target sites for DNA-binding proteins involved in pyrimidine- and purine-specific repression of the upstream promoter P1. We introduced deletions and insertions, and combinations thereof, in four linkers connecting the binding sites for integration host factor (IHF), PepA, PurR, and RNA polymerase and studied the importance of phasing and spacing of the targets and the importance of the nucleotide sequence of the linkers. The two PepA binding sites must be properly aligned and separated with respect to each other and to the promoter for both pyrimidine- and purine-mediated repression. Similarly, the phasing and spacing of the IHF and PEPA2 sites are strictly constrained but only for pyrimidine-specific repression. The IHF target is even dispensable for purine-mediated regulation. Thus, a correct localization of PepA within the higher-order nucleoprotein complex is a prerequisite for the establishment of pyrimidine-mediated repression and for the coupling between purine- and pyrimidine-dependent regulation. Our data also suggest the existence of a novel cis-acting pyrimidine-specific regulatory target located around position −60. Finally, the analysis of a P1 derivative devoid of its control region has led to a reappraisal of the effect of excess adenine on P1 and has revealed that P1 has no need for a UP element.

scholarly journals Functional analysis of the integration host factor site of the σ54Pu promoter of Pseudomonas putida by in vivo UV imprinting

2011 ◽  
Vol 82 (3) ◽  
pp. 591-601 ◽  
Author(s):  
Marc Valls ◽  
Rafael Silva-Rocha ◽  
Ildefonso Cases ◽  
Amalia Muñoz ◽  
Víctor de Lorenzo
Keyword(s):  
Functional Analysis ◽  
Pseudomonas Putida ◽  
Integration Host Factor ◽  
Host Factor
Sign in / Sign up

Export Citation Format

Share Document