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Zhang Yinghua - - 2009
In this study, we observed a novel property of Escherichia coli Hfq protein: it possibly influenced extracellular indole levels. The extracellular indole concentrations were increased in Hfq mutant cells and decreased in Hfq overexpression cells in a cell density-dependent manner. The decreased extracellular indole levels in Hfq overexpression cells caused ...
Seki Eiko - - 2009
Cell-free protein synthesis systems are generally influenced by the nature of the cell extract, which contains various factors on the chromosomal DNA. Some of the Escherichia coli cell extract factors are essential, despite their negative effects on protein synthesis, because they are required during the cell growth and/or extract preparation ...
Marchand P - - 2009
It was observed that a biocatalyst prepared from dehydrated whole cells of a recombinant Escherichia coli (initially suspended in borate buffer) was able to hydrolyze gaseous 1-chlorobutane in a solid/gas reactor. Nevertheless, at 40 degrees C and for a 0.7 water activity, it rapidly lost its activity. The explanation of ...
Halpin R M - - 2010
AIMS: Adhesion of a micro-organism to a cell surface is often considered to be the first step in pathogenesis. Inhibiting this process may have therapeutic effects in vivo. This study investigates the inhibitory effects of various bovine whey products on the association of Salm. Typhimurium, E. coli O157:H7 and C. ...
Engl Christoph - - 2009
The phage shock protein (Psp) response in Gram-negative bacteria counteracts membrane stress. Transcription of the PspF regulon (pspABCDE and pspG) in Escherichia coli is induced upon stresses that dissipate the proton motive force (pmf). Using GFP fusions we have visualized the subcellular localizations of PspA (a negative regulator and effector ...
Noor Rashed - - 2009
To understand the mechanism of sigma(E)-dependent cell lysis, we examined the consequences of deletion derivatives of rpoE regulators rseA, rseB and rseC on sigma(E) transcription, on levels of free versus membrane-bound sigma(E) and on OMP-biogenesis limiting factor(s) that could impact cell lysis. RT-PCR showed that individual nonpolar DeltarseA and DeltarseB ...
Uehara Tsuyoshi - - 2009
Bacterial cytokinesis is coupled to the localized synthesis of new peptidoglycan (PG) at the division site. This newly generated septal PG is initially shared by the daughter cells. In Escherichia coli and other gram-negative bacteria, it is split shortly after it is made to promote daughter cell separation and allow ...
Nozaki Shingo - - 2009
DnaA is a replication initiator protein that is conserved among bacteria. It plays a central role in the initiation of DNA replication. In order to monitor its behavior in living Escherichia coli cells, a nonessential portion of the protein was replaced by a fluorescent protein. Such a strain grew normally, ...
Kim Donghak - - 2009
The catalytic turnover of cytochrome P450( cam ) from Pseudomonas putida requires two auxiliary reduction partners, putidaredoxin (Pd) and putidaredoxin reductase (PdR). We report the functional expression in Escherichia coli of tricistronic constructs consisting of P450( cam ) encoded by the first cistron and the auxiliary proteins, Pd and PdR ...
Vass S O - - 2009
Prodrug activation gene therapy is a developing approach to cancer treatment, whereby prodrug-activating enzymes are expressed in tumour cells. After administration of a non-toxic prodrug, its conversion to cytotoxic metabolites directly kills tumour cells expressing the activating enzyme, whereas the local spread of activated metabolites can kill nearby cells lacking ...
Shiomi Daisuke - - 2009
The bacterium Escherichia coli is rod-shaped, and a unit cell keeps regular dimensions of about 1.5 microm long and 0.5 microm wide. The rod-shaped cell is composed of two parts: a cylinder in the center and caps at both ends. The length of the cylinder corresponds to the length of ...
Boeneman Kelly - - 2009
DnaA initiates chromosomal replication in Escherichia coli at a well-regulated time in the cell cycle. To determine how the spatial distribution of DnaA is related to the location of chromosomal replication and other cell cycle events, the localization of DnaA in living cells was visualized by confocal fluorescence microscopy. The ...
Englert Derek L - - 2009
Chemotaxis is the migration of cells in gradients of chemoeffector molecules. Although multiple, competing gradients must often coexist in nature, conventional approaches for investigating bacterial chemotaxis are suboptimal for quantifying migration in response to gradients of multiple signals. In this work, we developed a microfluidic device for generating precise and ...
Shimizu Takeshi - - 2009
Shiga toxin 1 (Stx1) is located in the periplasmic fraction, while Stx2 is found in the extracellular fraction, suggesting that enterohemorrhagic Escherichia coli (EHEC) contains a specific Stx2 release system. Both stx(1) and stx(2) are found within the late operons of Stx-encoding phages. Stx2 production is greatly induced by mitomycin ...
Henricus Marsiyana M - - 2009
Self-assembled peptide microtubes are fabricated with the biopolymer chitosan. The microtubes are covalently attached to chitosan and the morphology of the chitosan assembled on the surface of the microtubes can be tuned by altering the pH of the growth solution. Cytotoxicity studies in the presence of mouse embryonic fibroblasts indicate ...
Harrison Joe J - - 2009
Escherichia coli is refractory to elevated doses of antibiotics when it is growing in a biofilm, and this is potentially due to high numbers of multidrug-tolerant persister cells in the surface-adherent population. Previously, the chromosomal toxin-antitoxin loci hipBA and relBE have been linked to the frequency at which persister cells ...
Augustus Anne M - - 2009
Atomic level characterization of proteins and other macromolecules in the living cell is challenging. Recent advances in NMR instrumentation and methods, however, have enabled in-cell studies with prospects for multidimensional spectral characterization of individual macromolecular components. We present NMR data on the in-cell behavior of the MetJ repressor from Escherichia ...
Klayman Benjamin J - - 2009
The ability of a strain of waterborne Escherichia coli O157:H7 to colonize a glass flow cell and develop microcolonies when grown alone and with Pseudomonas aeruginosa PAO1 was examined. When introduced alone, planktonic E. coil were unable to attach to the glass surface. When introduced simultaneously with P. aeruginosa (co-inoculation), ...
Chu Yi-Fang - - 2009
Biosensors based on whole-cell bioluminescence have the potential to become a cost-effective alternative to conventional detection methods upon validation of target selectivity and sensitivity. However, quantitative analysis of bioluminescence is greatly hindered due to lack of control over the total number of cells in a suspending culture. In this study, ...
Cabeen Matthew T - - 2009
The cytoskeleton is a key regulator of cell morphogenesis. Crescentin, a bacterial intermediate filament-like protein, is required for the curved shape of Caulobacter crescentus and localizes to the inner cell curvature. Here, we show that crescentin forms a single filamentous structure that collapses into a helix when detached from the ...
van Bloois Edwin - - 2009
Streptomyces coelicolor A3(2) alditol oxidase (AldO) is a soluble monomeric flavoprotein in which the flavin cofactor is covalently linked to the polypeptide chain. AldO displays high reactivity towards different polyols such as xylitol and sorbitol. These characteristics make AldO industrially relevant, but full biotechnological exploitation of this enzyme is at ...
Van Gerven Nani - - 2009
Surface exposure of antigens on bacterial cells can be critical for eliciting an effective antibody response. Therefore, we investigated the cellular localization of the fimbrial F17a-G receptor-binding domain, fused to the translocator domain of the AIDA-I autotransporter. Synthesis of the fusion protein, under the control of the L-arabinose-inducible PBAD promoter, ...
Want Andrew - - 2009
Microbiology is important to industry therefore rapid and statistically representative measurements of cell physiological state, proliferation, and viability are essential if informed decisions about fermentation bioprocess optimization or control are to be made, because process performance will depend largely on the number of metabolically active viable cells. Samples of recombinant ...
Jandu Narveen - - 2009
Enterohaemorrhagic Escherichia coli (EHEC) O157:H7 inhibits interferon (IFN)-gamma-stimulated tyrosine phosphorylation of signal transducer and activator of transcription (STAT)-1 in epithelial cells. We determined the effects of probiotics on EHEC-mediated disruption of IFN-gamma-stimulated STAT-1 activation in epithelial cell lines. Confluent Intestine 407, HEp-2 and Caco-2 epithelial cells were pre-treated (3 h) ...
Black D Glenn - - 2009
Studies have explored the use of various nonlinear regression techniques to better describe shoulder and/or tailing effects in survivor curves. Researchers have compiled and developed a number of diverse models for describing microbial inactivation and presented goodness of fit analysis to compare them. However, varying physiological states of microorganisms could ...
Puertollano E - - 2009
AIMS: The ability of concentrated supernatants from Lactobacillus plantarum to produce a disruption of plasma membrane in eukaryotic and prokaryotic cells has been examined. METHODS AND RESULTS: A strain of Lact. plantarum (tolerant to acid and bile salts and resistant to several antibiotics) was used. It inhibited the growth of ...
Ogawa Tetsuhiro - - 2009
Colicin E5 is a ribonuclease that specifically cleaves tRNA(Tyr), tRNA(His), tRNA(Asn) and tRNA(Asp) of sensitive Escherichia coli cells by recognizing their anticodon sequences. Since all organisms possess universal anticodons of these tRNAs, colicin E5 was expected to potentially cleave eukaryotic tRNAs. Here, we expressed the active domain of colicin E5 ...
Kawano Hiroaki - - 2009
We designed and constructed six major toxin-antitoxin disruptants (DeltachpBIK, DeltadinJ-yafQ, DeltahipBA, DeltamazEF, DeltarelBE, and DeltayefM-yoeB) of Escherichia coli K-12 W3110. On prolonged cultivation of these disruptants with minimal M9 medium, the DeltahipBA cells exhibited a significantly longer life span than that of the other disruptants and of wild-type cells, as ...
Zhang Min - - 2009
BACKGROUND: In E. coli, the Min operon (MinCDE) plays a key role in determining the site of cell division. MinE oscillates from the middle to one pole or another to drive the MinCD complex to the end of the cell. The MinCD complex prevents FtsZ ring formation and the subsequent ...
Pisharath Harshan - - 2009
Prodrug dependent cell ablation is a method that allows inducible and spatially restricted cell destruction. We describe transgenic methods to express the Escherichia coli nfsB in a tissue restricted manner in the zebrafish. This bacterial gene encodes a nitroreductase (NTR) enzyme that can render prodrugs such as metronidazole (Met) cytotoxic. ...
Noor Rashed - - 2009
Sigma(E), encoded by rpoE, causes lysis of viable but nonculturable (VBNC) cells at the early stationary phase in Escherichia coli. However, the factors that trigger this lysis phenomenon remain unidentified. In this study, we found that the defective strain of katE, encoding catalase, exhibited a sigma(E)-dependent cell lysis phenotype, showing ...
Prokhorenko Isabella R - - 2009
Gram-negative bacteria can enter the bloodstream and interact with serum cationic proteins. The character of interaction will depend on the surface characteristics of bacterial cells, which are determined by bacterial chemotype and density of lipopolysaccharide (LPS) packing in the cell wall. It was shown that the lysozyme treatment resulted in ...
Lin Liang-I - - 2009
Microfabricated devices have great potential in cell-level studies, but are not easily accessible for the broad biology community. This paper introduces the Microscale Oil-Covered Cell Array (MOCCA) as a low-cost device for high throughput single-cell analysis that can be easily produced by researchers without microengineering knowledge. Instead of using microfabricated ...
Wood Thomas K - - 2009
Biofilms transform independent cells into specialized cell communities. Here are presented some insights into biofilm formation ascertained with the best-characterized strain, Escherichia coli. Investigations of biofilm formation and inhibition with this strain using whole-transcriptome profiling coupled to phenotypic assays, in vivo DNA binding studies and isogenic mutants have led to ...
Goldberg Shalom D - - 2009
We have engineered the chemotaxis system of Escherichia coli to respond to molecules that are not attractants for wild-type cells. The system depends on an artificially introduced enzymatic activity that converts the target molecule into a ligand for an E. coli chemoreceptor, thereby enabling the cells to respond to the ...
Xie Xinkai X Department of Chemical and Biomolecular Engineering, University of California, 5531 Boelter Hall, 420 Westwood Plaza, UCLA, Los Angeles, California 90095, - - 2009
Simvastatin is the active pharmaceutical ingredient of the blockbuster cholesterol lowering drug Zocor. We have previously developed an Escherichia coli based whole-cell biocatalytic platform towards the synthesis of simvastatin sodium salt (SS) starting from the precursor monacolin J sodium salt (MJSS). The centerpiece of the biocatalytic approach is the simvastatin ...
Freire Patrick - - 2009
The morphogene bolA is a general stress response gene in Escherichia coli that induces a round morphology when overexpressed. Results presented in this report show that increased BolA levels can inhibit cell elongation mechanisms. MreB polymerization is crucial for the bacterial cell cytoskeleton, and this protein is essential for the ...
Smith A R W - - 2008
AIMS: This study investigates the effects of N-(n-dodecyl)diethanolamine (DDA) on enzymes and growing cells of Escherichia coli NCIMB 8277. METHODS AND RESULTS: Enzyme activities in the presence of DDA were determined by measuring substrate-dependent oxygen consumption by whole cells, or of NADH formation or oxidation by cell extracts. Lysis of ...
Philippe Nadège - - 2009
Peptidoglycan is the major component of the bacterial cell wall and is involved in osmotic protection and in determining cell shape. Cell shape potentially influences many processes, including nutrient uptake as well as cell survival and growth. Peptidoglycan is a dynamic structure that changes during the growth cycle. Penicillin-binding proteins ...
Wang Hui - - 2008
Chemotaxis receptors in E. coli form clusters at the cell poles and also laterally along the cell body, and this clustering plays an important role in signal transduction. Recently, experiments using fluorescence imaging have shown that, during cell growth, lateral clusters form at positions approximately periodically spaced along the cell ...
Sorrentino Angela - - 2008
Puroindolines are two small proteins so called for the presence of an hydrophobic tryptophan-rich domain. Associated to wheat starch granules in Triticum aestivum, puroindolines have been shown to be responsible for the softness of the wheat endosperm. Moreover, have been proved to possess bactericide and anti-fungal properties together with the ...
Shiomi Daisuke - - 2008
Cell shape is critical for growth, and some genes are involved in bacterial cell morphogenesis. Here, we report a novel gene, rodZ, required for the determination of rod shape in Escherichia coli. Cells lacking rodZ no longer had rod shape but rather were round or oval. These round cells were ...
Clarke Margaret - - 2008
Bacteria have evolved numerous mechanisms for cell-cell communication, many of which have important consequences for human health. Among these is conjugation, the direct transfer of DNA from one cell to another. For gram-negative bacteria, conjugation requires thin, flexible filaments (conjugative pili) that are elaborated by DNA donor cells. The structure, ...
Tamura Asuka - - 2008
We developed a simple and efficient synthesis for 4-pyridoxolactone starting with pyridoxine and using a whole-cell biotransformation by two transformed Escherichia coli cell types. One set of transformed cells expressed pyridoxine 4-oxidase, catalase, and chaperonin, while the second set expressed pyridoxal 4-dehydrogenase. With this combination of cells, pyridoxine was first ...
Rozen Daniel E - - 2009
Bacterial populations can evolve and adapt to become diverse niche specialists, even in seemingly homogeneous environments. One source of this diversity arises from newly 'constructed' niches that result from the activities of the bacteria themselves. Ecotypes specialized to exploit these distinct niches can subsequently coexist via frequency-dependent interactions. Here, we ...
Yang Chao - - 2008
Surface display of the active proteins on living cells has enormous potential in the degradation of numerous toxic compounds. Here, we report the codisplay of organophosphorus hydrolase (OPH) and enhanced green fluorescent protein (GFP) on the cell surface of Escherichia coli by use of the truncated ice nucleation protein (INPNC) ...
Tazehkand Shiva S - - 2008
The effect of cell preparation methods on the surface chemistry and retention of Escherichia coli D21 g was investigated over a range of ionic strength conditions. The cell preparation methods that were considered included filtration and centrifugation (at various speeds and for different durations). For a given ionic strength condition, ...
Raghava Smita - - 2009
Three-phase partitioning of cells was carried out by mixing t-butanol and ammonium sulfate with aqueous suspension of cells. Permeabilized cells formed the interface between aqueous and alcohol layers. A preincubation step in which cells were exposed to just t-butanol was found to tune the selectivity of permeabilized cells of Thermus ...
Choi Paul J - - 2008
By monitoring fluorescently labeled lactose permease with single-molecule sensitivity, we investigated the molecular mechanism of how an Escherichia coli cell with the lac operon switches from one phenotype to another. At intermediate inducer concentrations, a population of genetically identical cells exhibits two phenotypes: induced cells with highly fluorescent membranes and ...
Elizabeth Hulme S - - 2008
This paper describes the fabrication of a composite agar/PDMS device for enriching short cells in a population of motile Escherichia coli. The device incorporated ratcheting microchannels, which directed the motion of swimming cells of E. coli through the device, and three sorting junctions, which isolated successively shorter populations of bacteria. ...
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