Effects of reduced amount of RNA polymerase sigma factor on gene expression and growth of Escherichia coli: Studies of the rpoD40 (Amber) mutation

1981 ◽  
Vol 184 (2) ◽  
pp. 166-173 ◽  
Author(s):  
Toshio Osawa ◽  
Takashi Yura
Keyword(s):  
Gene Expression ◽  
Escherichia Coli ◽  
Rna Polymerase ◽  
Sigma Factor ◽  
Amber Mutation

scholarly journals A sigma factor toolbox for orthogonal gene expression in Escherichia coli

2018 ◽  
Vol 46 (4) ◽  
pp. 2133-2144 ◽  
Author(s):  
Indra Bervoets ◽  
Maarten Van Brempt ◽  
Katleen Van Nerom ◽  
Bob Van Hove ◽  
Jo Maertens ◽  
...  
Keyword(s):  
Gene Expression ◽  
Escherichia Coli ◽  
Sigma Factor ◽  
Expression In Escherichia Coli

An amber mutation in the gene encoding the beta' subunit of Escherichia coli RNA polymerase

1982 ◽  
Vol 152 (2) ◽  
pp. 736-746
Author(s):  
S P Ridley ◽  
M P Oeschger
Keyword(s):  
Escherichia Coli ◽  
High Temperature ◽  
Rna Polymerase ◽  
Coli Strain ◽  
Beta Subunit ◽  
Temperature Sensitive ◽  
Amber Mutation ◽  
Gene Encoding ◽  
Amber Suppressor

An Escherichia coli strain carrying an amber mutation (UAG) in rpoC, the gene encoding the beta prime subunit of RNA polymerase, was isolated after mutagenesis with nitrosoguanidine. The mutation was moved into an unmutagenized strain carrying the supD43,74 allele, which encodes a temperature-sensitive su1 amber suppressor, and sue alleles, which enhance the efficiency of the suppressor. In this background, beta prime is not synthesized at high temperature. Suppression of the mutation by the non-temperature-sensitive amber suppressor su1+ yields a protein which is functional at all temperatures examined (30, 37, and 42 degrees C).

scholarly journals Substitution of a Highly Conserved Histidine in the Escherichia coli Heat Shock Transcription Factor, σ32, Affects Promoter Utilization In Vitro and Leads to Overexpression of the Biofilm-Associated Flu Protein In Vivo

2007 ◽  
Vol 189 (23) ◽  
pp. 8430-8436 ◽  
Author(s):  
Olga V. Kourennaia ◽  
Pieter L. deHaseth
Keyword(s):  
Escherichia Coli ◽  
Heat Shock ◽  
Rna Polymerase ◽  
Sigma Factor ◽  
Stable Complex ◽  
Tryptophan Residue ◽  
Specific Sequence ◽  
Bacterial Rna

ABSTRACT The heat shock sigma factor (σ32 in Escherichia coli) directs the bacterial RNA polymerase to promoters of a specific sequence to form a stable complex, competent to initiate transcription of genes whose products mitigate the effects of exposure of the cell to high temperatures. The histidine at position 107 of σ32 is at the homologous position of a tryptophan residue at position 433 of the main sigma factor of E. coli, σ70. This tryptophan is essential for the strand separation step leading to the formation of the initiation-competent RNA polymerase-promoter complex. The heat shock sigma factors of all gammaproteobacteria sequenced have a histidine at this position, while in the alpha- and deltaproteobacteria, it is a tryptophan. In vitro the alanine-for-histidine substitution at position 107 (H107A) destabilizes complexes between the GroE promoter and RNA polymerase containing σ32, implying that H107 plays a role in formation or maintenance of the strand-separated complex. In vivo, the H107A substitution in σ32 impedes recovery from heat shock (exposure to 42°C), and it also leads to overexpression at lower temperatures (30°C) of the Flu protein, which is associated with biofilm formation.

scholarly journals Bacterial Two-Hybrid Analysis of Interactions between Region 4 of the ς70 Subunit of RNA Polymerase and the Transcriptional Regulators Rsd from Escherichia coli and AlgQ from Pseudomonas aeruginosa

2001 ◽  
Vol 183 (21) ◽  
pp. 6413-6421 ◽  
Author(s):  
Simon L. Dove ◽  
Ann Hochschild
Keyword(s):  
Gene Expression ◽  
Escherichia Coli ◽  
Pseudomonas Aeruginosa ◽  
Amino Acid ◽  
Rna Polymerase ◽  
Amino Acid Substitution ◽  
Transcriptional Regulators ◽  
Binding Motif ◽  
E Coli ◽  
Two Hybrid

ABSTRACT A number of transcriptional regulators mediate their effects through direct contact with the ς70 subunit ofEscherichia coli RNA polymerase (RNAP). In particular, several regulators have been shown to contact a C-terminal portion of ς70 that harbors conserved region 4. This region of ς contains a putative helix-turn-helix DNA-binding motif that contacts the −35 element of ς70-dependent promoters directly. Here we report the use of a recently developed bacterial two-hybrid system to study the interaction between the putative anti-ς factor Rsd and the ς70 subunit of E. coli RNAP. Using this system, we found that Rsd can interact with an 86-amino-acid C-terminal fragment of ς70 and also that amino acid substitution R596H, within region 4 of ς70, weakens this interaction. We demonstrated the specificity of this effect by showing that substitution R596H does not weaken the interaction between ς and two other regulators shown previously to contact region 4 of ς70. We also demonstrated that AlgQ, a homolog of Rsd that positively regulates virulence gene expression inPseudomonas aeruginosa, can contact the C-terminal region of the ς70 subunit of RNAP from this organism. We found that amino acid substitution R600H in ς70 fromP. aeruginosa, corresponding to the R596H substitution in E. coli ς70, specifically weakens the interaction between AlgQ and ς70. Taken together, our findings suggest that Rsd and AlgQ contact similar surfaces of RNAP present in region 4 of ς70 and probably regulate gene expression through this contact.

scholarly journals Adaptive Mutations in RNA Polymerase and the Transcriptional Terminator Rho Have Similar Effects on Escherichia coli Gene Expression

2017 ◽  
Vol 34 (11) ◽  
pp. 2839-2855 ◽  
Author(s):  
Andrea González-González ◽  
Shaun M. Hug ◽  
Alejandra Rodríguez-Verdugo ◽  
Jagdish Suresh Patel ◽  
Brandon S. Gaut
Keyword(s):  
Gene Expression ◽  
Escherichia Coli ◽  
Rna Polymerase ◽  
Transcriptional Terminator ◽  
Adaptive Mutations

scholarly journals Expression of spoIIIJ in the Prespore Is Sufficient for Activation of σG and for Sporulation in Bacillus subtilis

2003 ◽  
Vol 185 (13) ◽  
pp. 3905-3917 ◽  
Author(s):  
Mónica Serrano ◽  
Luísa Côrte ◽  
Jason Opdyke ◽  
Charles P. Moran, ◽  
Adriano O. Henriques
Keyword(s):  
Gene Expression ◽  
Bacillus Subtilis ◽  
Rna Polymerase ◽  
Sigma Factor ◽  
Vegetative Growth ◽  
Mother Cell ◽  
Asymmetric Division ◽  
Developmental Program ◽  
Inactive Form

ABSTRACT During sporulation in Bacillus subtilis, the prespore-specific developmental program is initiated soon after asymmetric division of the sporangium by the compartment-specific activation of RNA polymerase sigma factor σF. σF directs transcription of spoIIIG, encoding the late forespore-specific regulator σG. Following synthesis, σG is initially kept in an inactive form, presumably because it is bound to the SpoIIAB anti-sigma factor. Activation of σG occurs only after the complete engulfment of the prespore by the mother cell. Mutations in spoIIIJ arrest sporulation soon after conclusion of the engulfment process and prevent activation of σG. Here we show that σG accumulates but is mostly inactive in a spoIIIJ mutant. We also show that expression of the spoIIIGE155K allele, encoding a form of σG that is not efficiently bound by SpoIIAB in vitro, restores σG-directed gene expression to a spoIIIJ mutant. Expression of spoIIIJ occurs during vegetative growth. However, we show that expression of spoIIIJ in the prespore is sufficient for σG activation and for sporulation. Mutations in the mother cell-specific spoIIIA locus are known to arrest sporulation just after completion of the engulfment process. Previous work has also shown that σG accumulates in an inactive form in spoIIIA mutants and that the need for spoIIIA expression for σG activation can be circumvented by the spoIIIGE155K allele. However, in contrast to the case for spoIIIJ, we show that expression of spoIIIA in the prespore does not support efficient sporulation. The results suggest that the activation of σG at the end of the engulfment process involves the action of spoIIIA from the mother cell and of spoIIIJ from the prespore.

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