scholarly journals DksA Is Required for Growth Phase-Dependent Regulation, Growth Rate-Dependent Control, and Stringent Control of fis Expression in Escherichia coli

2006 ◽  
Vol 188 (16) ◽  
pp. 5775-5782 ◽  
Author(s):  
Prabhat Mallik ◽  
Brian J. Paul ◽  
Steven T. Rutherford ◽  
Richard L. Gourse ◽  
Robert Osuna
Keyword(s):  
Escherichia Coli ◽  
Growth Rate ◽  
Amino Acid ◽  
Rna Polymerase ◽  
Growth Phase ◽  
Stationary Growth ◽  
Rate Dependent ◽  
Transcription In Vitro ◽  
State Growth

ABSTRACT DksA is a critical transcription factor in Escherichia coli that binds to RNA polymerase and potentiates control of rRNA promoters and certain amino acid promoters. Given the kinetic similarities between rRNA promoters and the fis promoter (Pfis), we investigated the possibility that DksA might also control transcription from Pfis. We show that the absence of dksA extends transcription from Pfis well into the late logarithmic and stationary growth phases, demonstrating the importance of DksA for growth phase-dependent regulation of fis. We also show that transcription from Pfis increases with steady-state growth rate and that dksA is absolutely required for this regulation. In addition, both DksA and ppGpp are required for inhibition of Pfis promoter activity following amino acid starvation, and these factors act directly and synergistically to negatively control Pfis transcription in vitro. DksA decreases the half-life of the intrinsically short-lived fis promoter-RNA polymerase complex and increases its sensitivity to the concentration of CTP, the predominant initiating nucleotide triphosphate for this promoter. This work extends our understanding of the multiple factors controlling fis expression and demonstrates the generality of the DksA requirement for regulation of kinetically similar promoters.

scholarly journals Growth Phase and Growth Rate Regulation of therapA Gene, Encoding the RNA Polymerase-Associated Protein RapA in Escherichia coli

2001 ◽  
Vol 183 (20) ◽  
pp. 6126-6134 ◽  
Author(s):  
Julio E. Cabrera ◽  
Ding Jun Jin
Keyword(s):  
Escherichia Coli ◽  
Growth Rate ◽  
Rna Polymerase ◽  
Growth Phase ◽  
Gene Encoding ◽  
Rate Regulation ◽  
E Coli ◽  
Growth Rate Control

ABSTRACT The Escherichia coli rapA gene encodes the RNA polymerase (RNAP)-associated protein RapA, which is a bacterial member of the SWI/SNF helicase-like protein family. We have studied therapA promoter and its regulation in vivo and determined the interaction between RNAP and the promoter in vitro. We have found that the expression of rapA is growth phase dependent, peaking at the early log phase. The growth phase control ofrapA is determined at least by one particular feature of the promoter: it uses CTP as the transcription-initiating nucleotide instead of a purine, which is used for most E. colipromoters. We also found that the rapA promoter is subject to growth rate regulation in vivo and that it forms intrinsic unstable initiation complexes with RNAP in vitro. Furthermore, we have shown that a GC-rich or discriminator sequence between the −10 and +1 positions of the rapA promoter is responsible for its growth rate control and the instability of its initiation complexes with RNAP.

scholarly journals Mutational Analysis of the Chlamydia trachomatis rRNA P1 Promoter Defines Four Regions Important for Transcription In Vitro

1998 ◽  
Vol 180 (9) ◽  
pp. 2359-2366 ◽  
Author(s):  
Ming Tan ◽  
Tamas Gaal ◽  
Richard L. Gourse ◽  
Joanne N. Engel
Keyword(s):  
Escherichia Coli ◽  
Chlamydia Trachomatis ◽  
Rna Polymerase ◽  
Mutational Analysis ◽  
In Vitro Transcription ◽  
Rna Polymerases ◽  
Rich Region ◽  
E Coli ◽  
Transcription In Vitro

ABSTRACT We have characterized the Chlamydia trachomatisribosomal promoter, rRNA P1, by measuring the effect of substitutions and deletions on in vitro transcription with partially purifiedC. trachomatis RNA polymerase. Our analyses indicate that rRNA P1 contains potential −10 and −35 elements, analogous toEscherichia coli promoters recognized by E-ς70. We identified a novel AT-rich region immediately downstream of the −35 region. The effect of this region was specific for C. trachomatis RNA polymerase and strongly attenuated by single G or C substitutions. Upstream of the −35 region was an AT-rich sequence that enhanced transcription by C. trachomatis and E. coli RNA polymerases. We propose that this region functions as an UP element.

scholarly journals SarA Represses agr Operon Expression in a Purified In Vitro Staphylococcus aureusTranscription System

2000 ◽  
Vol 182 (20) ◽  
pp. 5893-5897 ◽  
Author(s):  
Swarup K. Chakrabarti ◽  
Tapan K. Misra
Keyword(s):  
Experimental Data ◽  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Rna Polymerase ◽  
Growth Phase ◽  
Surface Protein ◽  
Dependent Manner ◽  
Operon Expression ◽  
Chromosomal Loci

ABSTRACT Mutation and genetic complementation studies suggested that two chromosomal loci, agr and sar, are involved in the upregulation of several exotoxin genes and the downregulation of a number of surface protein genes in a growth phase-dependent manner inStaphylococcus aureus. We purified recombinant T7-tagged SarA from Escherichia coli and determined its effect on transcription from several S. aureus promoters by using purified RNA polymerase reconstituted with either ςA or ςB from S. aureus. Of the seven ςA-dependent promoters that we tested, SarA repressed transcription from agrP2, agrP3,cna, sarP1, and sea promoters and did not affect sec and znt promoters. Furthermore, SarA had no effect on transcription from the ςB-dependent sarP3 promoter. In vitro experimental data presented in this report suggest that SarA expression is autoregulated.

scholarly journals A Region of ςK Involved in Promoter Activation by GerE in Bacillus subtilis

1999 ◽  
Vol 181 (14) ◽  
pp. 4365-4373 ◽  
Author(s):  
Kathryn H. Wade ◽  
Ghislain Schyns ◽  
Jason A. Opdyke ◽  
Charles P. Moran
Keyword(s):  
Bacillus Subtilis ◽  
Amino Acid ◽  
Rna Polymerase ◽  
Promoter Activity ◽  
Amino Acid Substitutions ◽  
Amino Acid Residues ◽  
Transcription In Vitro ◽  
A Site ◽  
Initial Binding

ABSTRACT During endospore formation in Bacillus subtilis, the DNA binding protein GerE stimulates transcription from several promoters that are used by RNA polymerase containing ςK. GerE binds to a site on one of these promoters, cotX, that overlaps its −35 region. We tested the model that GerE interacts with ςK at the cotX promoter by seeking amino acid substitutions in ςK that interfered with GerE-dependent activation of the cotX promoter but which did not affect utilization of the ςK-dependent, GerE-independent promoter gerE. We identified two amino acid substitutions in ςK, E216K and H225Y, that decrease cotXpromoter utilization but do not affect gerE promoter activity. Alanine substitutions at these positions had similar effects. We also examined the effects of the E216A and H225Y substitutions in ςK on transcription in vitro. We found that these substitutions specifically reduced utilization of the cotXpromoter. These and other results suggest that the amino acid residues at positions 216 and 225 are required for GerE-dependentcotX promoter activity, that the histidine at position 225 of ςK may interact with GerE at the cotXpromoter, and that this interaction may facilitate the initial binding of ςK RNA polymerase to the cotX promoter. We also found that the alanine substitutions at positions 216 and 225 of ςK had no effect on utilization of the GerE-dependent promoter cotD, which contains GerE binding sites that do not overlap with its −35 region.

Growth rate-dependent regulation of RNA polymerase synthesis in Escherichia coli

1985 ◽  
Vol 201 (3) ◽  
pp. 379-386 ◽  
Author(s):  
Geoffrey Ralling ◽  
Sharon Bodrug ◽  
Thomas Linn
Keyword(s):  
Escherichia Coli ◽  
Growth Rate ◽  
Rna Polymerase ◽  
Rate Dependent

scholarly journals Activation of Escherichia coli leuVTranscription by FIS

1999 ◽  
Vol 181 (12) ◽  
pp. 3864-3868 ◽  
Author(s):  
Wilma Ross ◽  
Julia Salomon ◽  
Walter M. Holmes ◽  
Richard L. Gourse
Keyword(s):  
Escherichia Coli ◽  
Transcription Factor ◽  
Rna Polymerase ◽  
Stable Complex ◽  
Start Site ◽  
Transcription Start ◽  
Transcription In Vitro ◽  
A Site

ABSTRACT The transcription factor FIS has been implicated in the regulation of several stable RNA promoters, including that for the major tRNALeu species in Escherichia coli, tRNA1 Leu. However, no evidence for direct involvement of FIS in tRNA1 Leu expression has been reported. We show here that FIS binds to a site upstream of the leuVpromoter (centered at −71) and that it directly stimulatesleuV transcription in vitro. A mutation in the FIS binding site reduces transcription from a leuV promoter in strains containing FIS but has no effect on transcription in strains lacking FIS, indicating that FIS contributes to leuV expression in vivo. We also find that RNA polymerase forms an unusual heparin-sensitive complex with the leuV promoter, having a downstream protection boundary of ∼−7, and that the first two nucleotides of the transcript, GTP and UTP, are required for formation of a heparin-stable complex that extends downstream of the transcription start site. These studies have implications for the regulation of leuV transcription.

Sign in / Sign up

Export Citation Format

Share Document