prlF and yhaV encode a new toxin-antitoxin system in Escherichia coli. (2007)
Schmidt, O., Schuenemann, Verena, Hand, N.J., Silhavy, T.J., Martin, Joerg, Lupas, Andrei, ...
Toxin-antitoxin systems consist of a stable toxin, frequently with endonuclease activity, and a small, labile antitoxin, which sequesters the toxin into an inactive complex. Under unfavorable...
The response regulator SprE controls the stability of RpoS.
In Escherichia coli, the sigma factor, RpoS, is a central regulator in stationary-phase cells. We have identified a gene, sprE (stationary-phase regulator), as essential for the negative regulation...
Kenney, L J, Bauer, M D, Silhavy, T J
Osmoregulated porin gene expression in Escherichia coli is controlled by the two-component regulatory system EnvZ and OmpR. EnvZ, the osmosensor, is an inner membrane protein and a histidine kinase....
The wild-type LamB-LacZ hybrid protein inhibits the export machinery upon induction when assayed by biochemical and genetic techniques, a phenotype referred to as hybrid protein jamming. This hybrid...
The SecA protein of Escherichia coli is required for protein translocation from the cytoplasm. The complexity of SecA function is reflected by missense mutations in the secA gene that confer several...
Snyder, W B, Davis, L J, Danese, P N, Cosma, C L, Silhavy, T J
The LamB-LacZ-PhoA tripartite fusion protein is secreted to the periplasm, where it exerts a toxicity of unknown origin during high-level synthesis in the presence of the inducer maltose, a phenotype...
Multicopy suppression of cold-sensitive sec mutations in Escherichia coli.
Danese, P N, Murphy, C K, Silhavy, T J
Mutations in the secretory (sec) genes in Escherichia coli compromise protein translocation across the inner membrane and often confer conditional-lethal phenotypes. We have found that overproduction...
EnvZ and OmpR are the sensor and response regulator proteins of a two-component system that controls the porin regulon of Escherichia coli in response to osmolarity. Three enzymatic activities are...
Transduction of envelope stress in Escherichia coli by the Cpx two-component system.
Disruption of normal protein trafficking in the Escherichia coli cell envelope (inner membrane, periplasm, outer membrane) can activate two parallel, but distinct, signal transduction pathways. This...
Two-Dimensional Polyacrylamide Gel Electrophoresis of Envelope Proteins of Escherichia coli
Johnson, W. Charles, Silhavy, T. J., Boos, W.
A method of separating envelope proteins by two-dimensional polyacrylamide gel electrophoresis is described. Escherichia coli envelopes (inner and outer membranes) were prepared by French pressing...
PrlA and PrlG suppressors reduce the requirement for signal sequence recognition.
Flower, A M, Doebele, R C, Silhavy, T J
Selection for suppressors of defects in the signal sequence of secretory proteins has led most commonly to identification of prlA alleles and less often to identification of prlG alleles. These...
Proteins destined for either the periplasm or the outer membrane of Escherichia coli are translocated from the cytoplasm by a common mechanism. It is generally assumed that outer membrane proteins,...
Membrane-derived oligosaccharides affect porin osmoregulation only in media of low ionic strength.
Geiger, O, Russo, F D, Silhavy, T J, Kennedy, E P
Gram-negative bacteria grown under conditions of low osmolarity accumulate significant amounts of periplasmic glucans, membrane-derived oligosaccharides (MDO) in Escherichia coli and cyclic glucans...
Enhanced export of beta-galactosidase fusion proteins in prlF mutants is Lon dependent.
We have used fusions of the outer membrane protein LamB to beta-galactosidase (encoded by lacZ) to study the protein export process. This LamB-LacZ hybrid protein blocks export when synthesized at...
Conlin, C A, Trun, N J, Silhavy, T J, Miller, C G
Mutations at the Escherichia coli prlC locus suppress the export defect of certain lamB signal sequence mutations. The Salmonella typhimurium opdA gene encodes an endoprotease that can participate in...
cis-acting ompF mutations that result in OmpR-dependent constitutive expression.
OmpR and EnvZ differentially control the transcription of the major outer membrane porin genes, ompF and ompC, in Escherichia coli in response to the osmolarity of the medium. We have previously...
Kiino, D R, Phillips, G J, Silhavy, T J
We have cloned and determined the nucleotide sequence of the prlF gene. An open reading frame predicting a 111-amino-acid protein (Mr 12,351) with an acidic carboxy terminus was identified. The DNA...
EnvZ functions through OmpR to control porin gene expression in Escherichia coli K-12.
Slauch, J M, Garrett, S, Jackson, D E, Silhavy, T J
The regulatory proteins OmpR and EnvZ are both required to activate expression of the genes for the major outer membrane porin proteins, OmpF and OmpC, of Escherichia coli K-12. Here we show that...
A progenitor of the outer membrane LamB trimer.
During its localization to the outer membrane, LamB possesses distinctive biochemical properties as it passes through the cytoplasmic membrane. Because LamB entered this dynamic state with an...
Trun, N J, Stader, J, Lupas, A, Kumamoto, C, Silhavy, T J
We exploited the conditional-lethal phenotype of secB null mutations to demonstrate that SecB function was required for PrlA-mediated suppression of signal sequence mutations. The results of these...
EnvZ, a transmembrane environmental sensor of Escherichia coli K-12, is phosphorylated in vitro.
By fusing the transcriptional and translational start signals of lacZ to envZ, we have obtained high-level synthesis of a truncated EnvZ protein (EnvZ115) in which the first 38 amino acids of EnvZ...
One class of mutations in the envZ gene of Escherichia coli K-12 confers a pleiotropic defect on the expression of several genes, including ompF, lamB, and phoA, that are otherwise not commonly...
Slauch, J M, Russo, F D, Silhavy, T J
We have isolated mutations in rpoA, the gene encoding the alpha subunit of RNA polymerase, that specifically affect transcriptional control by OmpR and EnvZ, the two-component regulatory system that...
cis-acting sites required for osmoregulation of ompF expression in Escherichia coli K-12.
Ostrow, K S, Silhavy, T J, Garrett, S
OmpF and OmpC are major outer membrane proteins which form passive diffusion pores in Escherichia coli K-12. The expression of the structural genes for these proteins, ompF and ompC, is influenced by...
Garrett, S, Taylor, R K, Silhavy, T J
We isolated four independent amber mutations in gene envZ, whose product is involved in the regulation of porin protein genes ompF and ompC. The envZ amber strains exhibit an OmpF-/+ OmpC- porin...
D-ribose metabolism in Escherichia coli K-12: genetics, regulation, and transport.
Lopilato, J E, Garwin, J L, Emr, S D, Silhavy, T J, Beckwith, J R
We have isolated mutants defective in high-affinity D-ribose transport. The mutations map in rbsT or rbsB , the structural gene for ribose binding protein. rbsT consists of at least one gene coding...
The 42-1 lamB-lacZ gene fusion confers a conditionally lethal, export-dependent phenotype known as maltose sensitivity. A maltose-resistant mutant showing decreased beta-galactosidase activity of the...
Bremer, E, Silhavy, T J, Weisemann, J M, Weinstock, G M
We isolated a plaque-forming derivative of phage lambda, lambda placMu1 , that contains sequences from bacteriophage Mu enabling it to integrate into the Escherichia coli chromosome by means of the...
Selection for mutants altered in the expression or export of outer membrane porin OmpF.
Sodergren, E J, Davidson, J, Taylor, R K, Silhavy, T J
Strains in which the lacZ gene (which specifies beta-galactosidase) is fused to a gene encoding an envelope protein often exhibit a phenotype termed overproduction lethality. In such strains,...
Mutations that define the promoter of ompF, a gene specifying a major outer membrane porin protein.
Taylor, R K, Garrett, S, Sodergren, E, Silhavy, T J
Expression of the major porin structural genes, ompF and ompC, is influenced by medium osmotic strength and requires the products of two regulatory genes, ompR and envZ. To help define the sites...
Bremer, E, Silhavy, T J, Weinstock, G M
We have constructed several derivatives of bacteriophage lambda that translocate by using the transposition machinery of phage Mu (lambda placMu phages). Each phage carries the c end of Mu,...
Taylor, R K, Hall, M N, Enquist, L, Silhavy, T J
We report here on the cloning of a gene located within the ompB locus of E. coli K-12. This gene, designated ompR, resides on a 10.9-kilobase EcoRI fragment that we cloned, using a lambda vector and...
Transcriptional regulation of Escherichia coli K-12 major outer membrane protein 1b.
Eleven independent insertion mutations were isolated that prevented expression of major outer membrane protein 1b. Seven of the mutations were Mucts insertions located at ombP. These ompB::Mucts...
Brickman, E, Silhavy, T J, Bassford, P J, Shuman, H A, Beckwith, J R
We describe the genetic analysis of 21 Escherichia coli strains in which the amino-terminal sequence of beta-galactosidase has been removed and replaced by an amino-terminal sequence from one or...
Use of gene fusion to study secretion of maltose-binding protein into Escherichia coli periplasm.
Bassford, P J, Silhavy, T J, Beckwith, J R
We have employed the technique of gene fusion to fuse the LacZ gene encoding the cytoplasmic enzyme beta-galactosidase with the malE gene encoding the periplasmic maltose binding protein (MBP)....
Resolution of glpA and glpT loci into separate operons in Escherichia coli K-12 strains.
Miki, K, Silhavy, T J, Andrews, K J
The independent insertion of bacteriophage Mu into the gene coding for anaerobic sn-glycerol 3-phosphate dehydrogenase (glpA) or into the genes coding for sn-glycerol 3-phosphate transport (glpT)...
A second transport system for sn-glycerol-3-phosphate in Escherichia coli.
Argast, M, Ludtke, D, Silhavy, T J, Boos, W
Strains containing phage Mucts inserted into glpT were isolated as fosfomycin-resistant clones. These mutants did not transport sn-glycerol-3-phosphate, and they lacked GLPT, a protein previously...
Garrett, S, Taylor, R K, Silhavy, T J, Berman, M L
We isolated a series of delta ompR delta envZ mutants by inducing a strain carrying a lambda prophage in the closely linked gene malP and screening the bacterial survivors for loss of the major outer...
Periplasmic protein related to the sn-glycerol-3-phosphate transport system of Escherichia coli.
Silhavy, T J, Hartig-Beecken, I, Boos, W
Two-dimensional gel electrophoresis of shock fluids of Escherichia coli K-12 revealed the presence of a periplasmic protein related to sn-glycerol-3-phosphate transport (GLPT) that is under the...
Strains of Escherichia coli in which lacZ (specifies beta-galactosidase) is fused to genes that specify exported proteins such as LamB (lambda receptor) exhibit unusual phenotypes. In particular,...
Intragenic regions required for LamB export.
Benson, S A, Bremer, E, Silhavy, T J
Escherichia coli strains containing a series of lamB-lacZ fusions have been isolated and characterized. Each of these fusions specifies a hybrid protein with LamB sequences at the NH2 terminus and a...
Weinstock, G M, Ap Rhys, C, Berman, M L, Hampar, B, Jackson, D, Silhavy, T J, ...
We have developed an Escherichia coli plasmid vector for the identification and expression of foreign DNA segments that are open reading frames (ORFs). The 5' end of ompF, an E. coli gene encoding an...
Importance of secondary structure in the signal sequence for protein secretion.
Mutant Escherichia coli strains in which export of the LamB protein (coded for by the lamB gene) to the outer membrane of the cell is prevented have been described previously. One of these mutant...
Emr, S D, Schwartz, M, Silhavy, T J
Two mutant strains of Escherichia coli have been isolated in which the cellular location of an outer membrane protein, the phage lambda receptor (the lamB gene product), is altered. These mutations...
Flower, A M, Osborne, R S, Silhavy, T J
The secretion of proteins from the cytoplasm of Escherichia coli requires the interaction of two integral inner membrane components, SecY and SecE. We have devised a genetic approach to probe the...
PrlA suppressor mutations cluster in regions corresponding to three distinct topological domains.
The SecY protein of Escherichia coli and its homologues in other organisms, are integral components of the cellular protein translocation machinery. Suppressor mutations that alter SecY (the prlA...
Conversion of beta-galactosidase to a membrane-bound state by gene fusion.
Silhavy, T J, Casadaban, M J, Shuman, H A, Beckwith, J R
We have isolated a series of strains in which the lacZ gene has been fused to one of the maltose operons, such that the synthesis of beta-galactosidase (beta-D-galactoside galactohydrolase; EC...
Use of gene fusions to study outer membrane protein localization in Escherichia coli.
Silhavy, T J, Shuman, H A, Beckwith, J, Schwartz, M
Escherichia coli strains have been isolated that produce hybrid proteins comprised of an NH2-terminal sequence from the lamB gene product (an outer membrane protein) and a major portion of the...
On the significance of the retention of ligand by protein.
Silhavy, T J, Szmelcman, S, Boos, W, Schwartz, M
When a solution of binding protein and its ligand is dialyzed against a large volume of ligand-free medium the rate of exit of the ligand from the protein-containing compartment can be extremely...
Schatz, P J, Bieker, K L, Ottemann, K M, Silhavy, T J, Beckwith, J
The E. coli secE (prlG) gene codes for an integral cytoplasmic membrane protein which is part of the cell's secretory machinery. A deletion of nearly the entire gene renders the cell dependent on the...
Jones, C H, Danese, P N, Pinkner, J S, Silhavy, T J, Hultgren, S J
The assembly of interactive protein subunits into extracellular structures, such as pilus fibers in the Enterobacteriaceae, is dependent on the activity of PapD-like periplasmic chaperones. The...
Van Der Wolk, J P, Fekkes, P, Boorsma, A, Huie, J L, Silhavy, T J, Driessen, A J
In Escherichia coli, precursor proteins are translocated across the cytoplasmic membrane by translocase. This multisubunit enzyme consists of a preprotein-binding and ATPase domain, SecA, and the...
The sec/prl gene products catalyze the translocation of precursor proteins from the cytoplasm of Escherichia coli. Recessive, conditionally lethal mutant alleles of these genes (sec mutations) cause...
Escherichia Coli Xona (Sbcb) Mutants Enhance Illegitimate Recombination
Allgood, N. D., Silhavy, T. J.
Mutations of Escherichia coli K-12 were isolated that increase the frequency of deletion formation. Three of these mutations map to the gene sbcB at 43.5 min on the E. coli chromosome. Two types of...
The response regulator SprE controls the stability of RpoS.
In Escherichia coli, the sigma factor, RpoS, is a central regulator in stationary-phase cells. We have identified a gene, sprE (stationary-phase regulator), as essential for the negative regulation...
Kenney, L J, Bauer, M D, Silhavy, T J
Osmoregulated porin gene expression in Escherichia coli is controlled by the two-component regulatory system EnvZ and OmpR. EnvZ, the osmosensor, is an inner membrane protein and a histidine kinase....
The wild-type LamB-LacZ hybrid protein inhibits the export machinery upon induction when assayed by biochemical and genetic techniques, a phenotype referred to as hybrid protein jamming. This hybrid...
The SecA protein of Escherichia coli is required for protein translocation from the cytoplasm. The complexity of SecA function is reflected by missense mutations in the secA gene that confer several...
Snyder, W B, Davis, L J, Danese, P N, Cosma, C L, Silhavy, T J
The LamB-LacZ-PhoA tripartite fusion protein is secreted to the periplasm, where it exerts a toxicity of unknown origin during high-level synthesis in the presence of the inducer maltose, a phenotype...
Multicopy suppression of cold-sensitive sec mutations in Escherichia coli.
Danese, P N, Murphy, C K, Silhavy, T J
Mutations in the secretory (sec) genes in Escherichia coli compromise protein translocation across the inner membrane and often confer conditional-lethal phenotypes. We have found that overproduction...
EnvZ and OmpR are the sensor and response regulator proteins of a two-component system that controls the porin regulon of Escherichia coli in response to osmolarity. Three enzymatic activities are...
Transduction of envelope stress in Escherichia coli by the Cpx two-component system.
Disruption of normal protein trafficking in the Escherichia coli cell envelope (inner membrane, periplasm, outer membrane) can activate two parallel, but distinct, signal transduction pathways. This...
Two-Dimensional Polyacrylamide Gel Electrophoresis of Envelope Proteins of Escherichia coli
Johnson, W. Charles, Silhavy, T. J., Boos, W.
A method of separating envelope proteins by two-dimensional polyacrylamide gel electrophoresis is described. Escherichia coli envelopes (inner and outer membranes) were prepared by French pressing...
PrlA and PrlG suppressors reduce the requirement for signal sequence recognition.
Flower, A M, Doebele, R C, Silhavy, T J
Selection for suppressors of defects in the signal sequence of secretory proteins has led most commonly to identification of prlA alleles and less often to identification of prlG alleles. These...
Proteins destined for either the periplasm or the outer membrane of Escherichia coli are translocated from the cytoplasm by a common mechanism. It is generally assumed that outer membrane proteins,...
Membrane-derived oligosaccharides affect porin osmoregulation only in media of low ionic strength.
Geiger, O, Russo, F D, Silhavy, T J, Kennedy, E P
Gram-negative bacteria grown under conditions of low osmolarity accumulate significant amounts of periplasmic glucans, membrane-derived oligosaccharides (MDO) in Escherichia coli and cyclic glucans...
Enhanced export of beta-galactosidase fusion proteins in prlF mutants is Lon dependent.
We have used fusions of the outer membrane protein LamB to beta-galactosidase (encoded by lacZ) to study the protein export process. This LamB-LacZ hybrid protein blocks export when synthesized at...
Conlin, C A, Trun, N J, Silhavy, T J, Miller, C G
Mutations at the Escherichia coli prlC locus suppress the export defect of certain lamB signal sequence mutations. The Salmonella typhimurium opdA gene encodes an endoprotease that can participate in...
cis-acting ompF mutations that result in OmpR-dependent constitutive expression.
OmpR and EnvZ differentially control the transcription of the major outer membrane porin genes, ompF and ompC, in Escherichia coli in response to the osmolarity of the medium. We have previously...
Kiino, D R, Phillips, G J, Silhavy, T J
We have cloned and determined the nucleotide sequence of the prlF gene. An open reading frame predicting a 111-amino-acid protein (Mr 12,351) with an acidic carboxy terminus was identified. The DNA...
EnvZ functions through OmpR to control porin gene expression in Escherichia coli K-12.
Slauch, J M, Garrett, S, Jackson, D E, Silhavy, T J
The regulatory proteins OmpR and EnvZ are both required to activate expression of the genes for the major outer membrane porin proteins, OmpF and OmpC, of Escherichia coli K-12. Here we show that...
A progenitor of the outer membrane LamB trimer.
During its localization to the outer membrane, LamB possesses distinctive biochemical properties as it passes through the cytoplasmic membrane. Because LamB entered this dynamic state with an...
Trun, N J, Stader, J, Lupas, A, Kumamoto, C, Silhavy, T J
We exploited the conditional-lethal phenotype of secB null mutations to demonstrate that SecB function was required for PrlA-mediated suppression of signal sequence mutations. The results of these...
EnvZ, a transmembrane environmental sensor of Escherichia coli K-12, is phosphorylated in vitro.
By fusing the transcriptional and translational start signals of lacZ to envZ, we have obtained high-level synthesis of a truncated EnvZ protein (EnvZ115) in which the first 38 amino acids of EnvZ...
One class of mutations in the envZ gene of Escherichia coli K-12 confers a pleiotropic defect on the expression of several genes, including ompF, lamB, and phoA, that are otherwise not commonly...
Slauch, J M, Russo, F D, Silhavy, T J
We have isolated mutations in rpoA, the gene encoding the alpha subunit of RNA polymerase, that specifically affect transcriptional control by OmpR and EnvZ, the two-component regulatory system that...