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Dainiak, Maria B.
Macroporous monolithic hydrogels (cryogel monoliths; rods 12.5 mm x 7.1 mm diameter) are elastic, sponge-like materials with large (10-100 mu m), interconnected pores. Phenyl- and IMAC-(Me(II)-iminodiacetic acid)-cryogel monoliths were inserted into the open-ended wells of a standard 96-well plate, forming a system of 96 drainage-protected minicolumns, and were used in ...
Jaeger, Tina
Almost all bacteria possess a rigid exoskeleton (murein sacculus) that renders the cell osmotically stable. The murein heteropolymer (or peptidoglycan) is made up of glycan chains, consisting of alternating N-acetylmuramic acid (MurNAc) and N-acetylglucosamine (GlcNAc) subunits, interlinked by short peptide bridges. To enable the insertion of new peptidoglycan during cell ...
Khattar Medhat M - - 2007
In 1993, William Donachie wrote "The success of molecular genetics in the study of bacterial cell division has been so great that we find ourselves, armed with much greater knowledge of detail, confronted once again with the same naive questions that we set to answer in the first place". Indeed, ...
Lutkenhaus Joe - - 2007
The positioning of a cytoskeletal element that dictates the division plane is a fundamental problem in biology. The assembly and positioning of this cytoskeletal element has to be coordinated with DNA segregation and cell growth to ensure that equal-sized progeny cells are produced, each with a copy of the chromosome. ...
Gadomska Grazyna - - 2007
The aspartase overproducing mutant B-715 was used as a donor of the aspartase gene for further construction of the aspartase-hyperproducing strains by molecular cloning. In preliminary experiments activity of transformants and their efficiency in L-aspartic acid biosynthesis were compared. The conditions for recombinant strain multiplication, biomass activation and L-aspartic acid ...
Darnton Nicholas C - - 2007
Bacteria swim by rotating long thin helical filaments, each driven at its base by a reversible rotary motor. When the motors of peritrichous cells turn counterclockwise (CCW), their filaments form bundles that drive the cells forward. We imaged fluorescently labeled cells of Escherichia coli with a high-speed charge-coupled-device camera (500 ...
Oulé Mathias K - - 2006
The effects of pressurized CO2 on the survival of Escherichia coli and the mechanism of cell inactivation were studied. Bacterial cultures were inoculated in nutrient broth and incubated at 30 degrees C for 18 h. Exposure of the cells to CO2 under pressures ranging from 2.5 to 25 MPa and ...
Yu H - - 2006
AIMS: To determine the effects of surface cell concentration and phase of growth on the inactivation of Escherichia coli cells using an atmospheric nonthermal plasma. METHODS AND RESULTS: Cells of E. coli K12 were deposited onto the surface of membrane filters and exposed to the plume from a cold atmospheric ...
Rouschop Kasper M A - - 2006
Escherichia coli is the most common pathogen found in urinary tract infections (UTIs), mainly affecting children and women. We report that CD44, a hyaluronic acid (HA) binding protein that mediates cell-cell and cell-matrix interactions, facilitates the interaction of E. coli with urothelial cells and thus the infection of the host. ...
Chan G - - 2006
The ability to recover cells from a fermentation broth in an intact form can be an important criterion for determining the overall performance of a recovery and purification sequence. Disruption of the cells can lead to undesired contamination of an extracellular product with intracellular components and vice versa loss of ...
Malik Muhammad - - 2007
Quinolone activity against Escherichia coli was examined during aerobic growth, aerobic treatment with chloramphenicol, and anaerobic growth. Nalidixic acid, norfloxacin, ciprofloxacin, and PD161144 were lethal for cultures growing aerobically, and the bacteriostatic activity of each quinolone was unaffected by anaerobic growth. However, lethal activity was distinct for each quinolone with ...
Yang Liu - - 2006
The effects of native and semisynthetic beta-lactam on the surface of E. coli cells were investigated using tapping mode atomic force microscopy (AFM). These studies were done on both single cell and cell colonies. This allowed us to achieve a complete understanding of the effects, since previous related AFM analysis ...
Helwig Ulf U University Hospital Schleswig-Holstein, Campus Kiel, 1st Medical Department, 24105 Kiel, Germany. - - 2006
To investigate whether the stimulation of peripheral blood mononuclear cells (PBMNC) with the cell debris and cell extraction of different probiotic strains is similar or species specific. Three strains of bifidobacteria, 4 strains of lactobacilli, and E. coli nissle were sonicated and centrifuged in order to divide them into cell ...
Anguera Montserrat C - - 2006
Recombinant mouse 5,10-methenyltetrahydrofolate synthetase (MTHFS) was expressed in Escherichia coli and shown to co-purify with a chromophore that had a lambda(max) at 320nm. The chromophore remained bound to MTHFS during extensive dialysis, but dissociated from MTHFS when its substrate, 5-formyltetrahydrofolate, was bound. The chromophore was identified as an oxidized catecholamine ...
Stenuit Ben - - 2006
Escherichia coli grew aerobically with 2,4,6-trinitrotoluene (TNT) as sole nitrogen source and caused TNT's partial denitration. This reaction was enhanced in nongrowing cell suspensions with 0.516 mol nitrite released per mol TNT. Cell extracts denitrated TNT in the presence of NAD(P)H. Isomers of amino-dimethyl-tetranitrobiphenyl were detected and confirmed with U-15N-labeled ...
Giamboi-Miraglia A - - 2007
Pathogenic Escherichia coli strains produce a number of virulence-associated factors, among which cytotoxic necrotizing factor 1 (CNF1). CNF1 is a chromosomally encoded toxin that permanently activates the small GTP-binding proteins of the Rho family (Rho, Rac and Cdc42) by catalizing their deamidation at a specific glutamine residue. This activation modulates ...
Pontes Gerlândia N - - 2006
A large number of data show that melatonin has immunomodulatory properties and is produced by immunocompetent cells; also, some evidence suggests a 'feedback' of the activated immune system on the pineal gland. In this paper, we studied immune-pineal interactions in colostrum obtained from healthy puerperae and mothers with mastitis taking ...
Smith Annie G - - 2006
Skin wounds derive therapeutic benefit from redeployment of dermal tissues, whether as split-thickness allo- and autografts or as biological dressings comprising cultured cells. However, the clinical outcome is strongly influenced by the techniques used for cell/tissue grafting and also the microbiological status of the wound. Here we report that microtopography ...
Li J - - 2006
Biological filters combining microbial activity and rapid sand filtration are used in drinking water treatment plants for enhanced biodegradable organic matters (BOM) removal. Biofilms formed on filter media comprised of bacteria enclosed in a polymeric matrix are responsible for the adsorption of BOM and attachment of planktonic microorganisms. This study ...
Caubet R - - 2006
Planktonic bacteria passing to a sessile state during the formation of a biofilm undergo many gene expression and phenotypic changes. These transformations require a significant time to establish. Inversely, cells extracted from a biofilm should also require a significant time before acquiring the same physiological characteristics as planktonic cells. Relatively ...
Villanacci V - - 2006
AIMS: To study relationships between the number of pseudomelanosis coli cells and that of colonic enteric neurons and interstitial cells of Cajal, which are significantly reduced compared with controls in severely constipated patients. Pseudomelanosis coli is frequent in patients using anthraquinone laxatives. It is not known whether the prolonged use ...
Yohe H C - - 2006
Integral components of mammalian cell membranes, glycosphingolipids (GSL) reside in specialized plasma membrane microdomains critical for cell signaling. N-alkylated nojirimycins are compounds developed for GSL substrate deprivation therapy, blocking GSL synthesis by specifically inhibiting an essential enzyme, ceramide glucosyltransferase. Peritoneal macrophages recruited in mice pretreated with an inhibitory N-alkylnojirimycin displayed ...
Mouri Tsuyoshi - - 2006
Catalytic activity of a recombinant Escherichia coli whole cell biocatalyst harboring a cytochrome P450cam monooxygenase system from Pseudomonas putida coupled with enzymatic co-factor regeneration was investigated. About 0.7 micromol camphor was hydroxylated per mg dry cells at 4 degrees C in 50 mM Tris/HCl buffer (pH 7.4) when utilizing a ...
Dainiak Maria B - - 2006
Suitable conditions for separating cells using a chromatographic procedure were evaluated in parallel chromatography on minicolumns. A 96-hole minicolumn plate filled with cryogel monoliths (18.8 mm x 7.1 mm Ø) with immobilized concanavalin A was used. Chromatographic columns (113 mm x 7.1 mm Ø) were used for chromatographic resolution of ...
Li Guanglai - - 2006
We determined the torque of the flagellar motor of Caulobacter crescentus for different motor rotation rates by measuring the rotation rate and swimming speed of the cell body and found it to be remarkably different from that of other bacteria, such as Escherichia coli and Vibrio alginolyticus. The average stall ...
Takayama Katsumi - - 2006
The gene encoding organophosphorus hydrolase (OPH) from Flavobacterium species was expressed on the cell surface of Saccharomyces cerevisiae MT8-1 using a glycosylphosphatidylinositol (GPI) anchor linked to the C-terminal region of OPH. Immunofluorescence microscopy confirmed the localization of OPH on the cell surface, and fluorescence intensity measurement of cells revealed that ...
Alonso-Casajús Nora - - 2006
To understand the biological function of bacterial glycogen phosphorylase (GlgP), we have produced and characterized Escherichia coli cells with null or altered glgP expression. glgP deletion mutants (DeltaglgP) totally lacked glycogen phosphorylase activity, indicating that all the enzymatic activity is dependent upon the glgP product. Moderate increases of glycogen phosphorylase ...
Hubbuch Jürgen J - - 2006
Expanded bed adsorption (EBA) is an integrative step in downstream processing allowing the direct capture of target proteins from cell-containing feedstocks. Extensive co-adsorption of biomass, however, may hamper the application of this technique. The latter is especially observed at anion exchange processes as cells or cell debris are negatively charged ...
Yim Sung-Kun - - 2006
To develop a whole-cell oxidoreductase system without the practical limitation of substrate/product transport, easy preparation, stability of enzymes, and low expression levels, we here report the development of a whole cell biocatalyst displaying rat NADPH-cytochrome P450 oxidoreductase (CPR, 77-kDa) on the surface of Escherichia coli by using ice-nucleation protein from ...
Awais Raheela - - 2006
A previously green fluorescent protein (GFP)-labeled PP01 virulent bacteriophage, specific to Escherichia coli O157:H7, was used to construct lysozyme-inactivated GFP-labeled PP01 phage (PP01e-/GFP). The new recombinant phage lacked lytic activity because of the inactivation of gene e, which produces the lysozyme responsible for cell lysis. Gene e was inactivated by ...
Daniels Karla J - - 2006
Upon homozygosis from a/alpha to a/a or alpha/alpha, Candida albicans must still switch from the 'white' to 'opaque' phenotype to mate. It was, therefore, surprising to discover that pheromone selectively upregulated mating-associated genes in mating-incompetent white cells without causing G1 arrest or shmoo formation. White cells, like opaque cells, possess ...
Critchley-Thorne Rebecca J - - 2006
We have investigated the tropism of nonpathogenic recombinant invasive Escherichia coli in the gastrointestinal tract and the efficacy of this invasive E. coli as an oral vaccine for cancer immunotherapy. E. coli expressing invasin from Yersinia pseudotuberculosis selectively invade nonphagocytic cells in which beta(1)-integrin is expressed and accessible. Following internalization ...
Okazaki Kumiko - - 2006
Most extant cyanobacteria contain C16 fatty acids in the sn-2 positions of glycerolipids, which are regulated by lysophosphatidic acid acyltransferase (LPAAT; EC 2.3.1.51). Synechocystis sp. PCC6803 contains sll1848, sll1752, and slr2060 as putative acyltransferase genes. sll1848 was recently reported to encode an indispensable palmitoyl-specific LPAAT; however, here we show that ...
Eto Danelle S - - 2006
Strains of uropathogenic Escherichia coli (UPEC) can invade terminally differentiated superficial bladder epithelial cells and subsequently multiply, forming large biofilm-like inclusions referred to as pods. In contrast, within immature bladder cells UPEC enter a more quiescent state and often fail to replicate appreciably. As immature bladder epithelial cells undergo terminal ...
Pap Gábor - - 2006
Neutrophil (PMNL) function is influenced by factors released by other immune cells during the course of the immune response. We investigated the effect of neutrophil cell density and the effect of supernatant of the phagocytosis assay on the phagocytosis activity of PMNLs. The measurements were carried out with naive (control) ...
Vidal Jorge E - - 2006
EspC is an autotransporter protein secreted by enteropathogenic Escherichia coli (EPEC). The pathogenic role of EspC in EPEC infection is unknown. We have shown that the purified EspC produces enterotoxicity and cytotoxicity; for the latter effect, EspC must be internalized. However, the internalization mechanism is unknown. Here we show that ...
Wu Mei Li - - 2006
The gene encoding chitinase 92 (Chi92) from Aeromonas hydrophila JP10 has been displayed on the cell surface of Escherichia coli using the N-terminal region of ice nucleation proteins (INPN) as an anchoring motif. Immunofluorescence microscopy confirmed that Chi92 was anchored on the cell surface. Western blot analysis further identified the ...
Kang Dong Gyun - - 2006
Although Escherichia coli can be genetically engineered to degrade environmental toxic organophosphate compounds (OPs) to nontoxic materials, a critical problem in such whole cell systems is limited substrate diffusion. The present work examined whether periplasmic expression of organophosphorus hydrolase (OPH) resulted in better whole cell enzymatic activity compared to standard ...
Cisneros Luis - - 2006
Recent experiments have shown large-scale dynamic coherence in suspensions of the bacterium B. subtilis, characterized by quorum polarity, collective parallel swimming of cells. To probe mechanisms leading to this, we study the response of individual cells to steric stress, and find that they can reverse swimming direction at spatial constrictions ...
Sobieszczanska Beata M - - 2006
Haemolysin alpha (HlyA) produced by cell-detaching Escherichia coli, a putative new class of enteric pathogen, is considered to be the main factor responsible for detachment of cells cultured in vitro. HlyA is one of the few E. coli proteins actively secreted into the medium during exponential growth. In the present ...
Chumpolkulwong Namthip - - 2006
We analyzed the effect of nine 'rare' codons (AGA, AGG, AUA, CCC, CGA, CGG, CUA, GGA, and UUA) on gene expression in an Escherichia coli coupled transcription/translation cell-free system, in comparison with a cell-based expression system. Each reporter gene contained five consecutive repeats of a rare codon, or in some ...
Shinkyo Raku - - 2006
Among polychlorinated dibenzo-p-dioxins (PCDDs), 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TetraCDD) is the most toxic one. Recently, we reported that rat CYP1A1 mutant, F240A, expressed in yeast showed metabolic activity toward 2,3,7,8-TetraCDD. In this study, we successfully expressed N-terminal truncated P450s (Delta1A1 and DeltaF240A) in Escherichia coli cells. Kinetic analysis using membrane fractions prepared from ...
Kulahava Tatsiana A - - 2006
Peroxynitrite is one of the most potent neurotoxic agents with multiple targets in neurons and glial cells. This study addressed a question of whether peroxynitrite-mediated cytotoxicity can be prevented by Escherichia coli lypopolisaccharide (LPS) due to its mitogenic activity towards C6 glioma cells. A number of characteristic morphological changes (processes ...
Yang Shirley - - 2006
Previously, we found that the quorum sensing transcription factor SdiA up-regulates AcrAB. Others found that a 4-quinolone was a quorum-sensing signal in Pseudomonas aeruginosa. In Escherichia coli, there are at least three multidrug transporters (AcrAB/TolC, MdfA, and NorE) that exude fluoroquinolones. Here, we show that DeltaacrAB, tolC210, or DeltanorE mutants ...
Na S H - - 2006
To verify the hypothesis of cryptic growth and viable but nonculturable (VBNC) state, survival responses of Escherichia coli cells were examined under oligotrophic microcosm conditions for an extended period. In the case of filtered distilled water at 4 degrees C, E. coli cells definitely entered the VBNC state within 56 ...
Hideaki Sasaki
Utilization of proline in <I>Escherichia coli</I> K-12 was analyzed at different osmolarities. Under the proline-base cultivation, sufficient growth of strain K-12 accompanied with high amount of proline uptake was observed in the presence of less than 0.5 M NaCl, where growth time lag was recognized. Distinct decrease in growth yield ...
Janmohamed Azara - - 2006
The baculovirus/insect cell heterologous expression system provides an important tool for investigating the catalytic activity of individual drug-metabolizing enzymes toward a particular substrate. In this chapter we describe a baculovirus/insect cell system that we have used for the expression of human and mouse flavin-containing monooxygenases. Methods are described for the ...
Cruzeiro-Silva C - - 2006
Structural studies by in-cell nuclear magnetic resonance are a developing new field of research, and their objective is to obtain structural information of proteins and other biological macromolecules in the cytoplasm of Escherichia coli cells. The major limitation of in-cell experiments is cell lysis that occurs during the experiments. In ...
Liu Peng - - 2006
The toxic mechanism of La3+ to Escherichia coli is investigated by detecting the concentration change of La3+ in E. coli cells growing in La3+-containing medium. Stimulatory action and inhibitory effect of La3+ in different concentrations can be attributed to the permeability alteration of the cell. Low concentration of La3+ increases ...
Shah Devang - - 2006
Bacterial populations contain persisters, phenotypic variants that constitute approximately 1% of cells in stationary phase and biofilm cultures. Multidrug tolerance of persisters is largely responsible for the inability of antibiotics to completely eradicate infections. Recent progress in understanding persisters is encouraging, but the main obstacle in understanding their nature was ...
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