Search results for "wall"

A search for beta-lactamase in chlamydiae, mycoplasmas, planctomycetes, and cyanelles: bacteria and bacterial descendants at different phylogenetic p…

2000

Bacteria from different phylogenetic positions such as chlamydiae, mycoplasmas, planctomycetes and also endosymbiotic murein-containing cyanelles were investigated for the production of beta-lactamases. No beta-lactamase activity was found in bacteria lacking murein such as Chlamydia pneumoniae, Mycoplasma pneumoniae, Pirellula marina and Planctomyces maris. In the murein-containing cyanelles of Cyanophora paradoxa no beta-lactamase activity could be detected.

Extraction of Enzymes from Tissues, Cells and Cell-Organelles

1994

Microorganisms, such as bacteria, algae, moulds and others, are ruptured by sonication, by passage through a French press [1, 2] (Fig. 2.1) or a Manton-Gaulin homogenizer [3], by blending with glass beads [4], or by digesting the cell walls enzymically [5]. Extract preparation is preferably performed in the cold (+4 °C).

Cell Wall Structures of Mesophilic, Thermophilic and Hyperthermophilic Archaea

2006

Isolation and characterization of yeast monomorphic mutants of Candida albicans.

1994

A method was devised for the isolation of yeast monomorphic (LEV) mutants of Candida albicans. By this procedure, about 20 stable yeast-like mutants were isolated after mutagenesis with ethyl methane sulfonate. The growth rate of the mutants in different carbon sources, both fermentable and not, was indistinguishable from that of the parental strain, but they were unable to grow as mycelial forms after application of any of the common effective inducers, i.e., heat shock, pH alterations, proline addition, or use of GlcNAc as the carbon source. Studies performed with one selected strain demonstrated that it had severe alterations in the chemical composition of the cell wall, mainly in the le…

Changes in the density of microtubular networks in mesophyll cells and mesophyll derived protoplasts of Nicotiana and Triticum during leaf development

1993

Changes in the density of microtubular mesh-works were analysed in mesophyll cells and mesophyll derived protoplasts of Nicotiana tabacum L. and Triticum aestivum L. during leaf development. The main purpose of this study was to test whether the low density, if not lack, of microtubular networks recently described in protoplasts that had been isolated from fully differentiated mesophyll cells happened during protoplast isolation or whether the loss of microtubules actually occurred during differentiation of the leaf tissue. Immunofluorescence microscopy showed that the density of the microtubular cytoskeleton in the leaf tissue decreased steadily after cessation of cell growth in both speci…

Immobilization of <i>Saccharomyces cerevisiae</i> Cells to Protein G-Sepharose by Cell Wall Engineering

2003

In this work, we explored the possibility of using the targeting of a heterologous protein to the cell wall of <i>Saccharomyces cerevisiae</i>, by fusing it to a cell wall protein, to construct yeast strains whose cells display on their surface proteins that bind to a matrix, so as to achieve the immobilization of the whole cells. With this aim, we created a gene fusion that comprises the region responsible for attachment of a cell wall protein to the cell wall, and the IgG binding region of staphylococcal protein A, and expressed it in the <i>mnn1mnn9</i> strain of <i>S. cerevisiae</i>. The surface display of the protein A-Icwp fusion protein was positiv…

Association with the Syndrome "Basses Richesses" of Sugar Beet of a Phytoplasma and a Bacterium-Like Organism Transmitted by a Pentastiridius sp.

2002

The syndrome “basses richesses” of sugar beet (SBR) was first observed in 1991 in Burgundy, France. A cixiid planthopper, Pentastiridius beieri, has been proved to be involved in the transmission to sugar beet of a stolbur phytoplasma, which could be detected in some affected plants. In 2000, periwinkle and sugar beet exposed to field-collected cixiids developed symptoms similar to SBR on sugar beet. Use of 4′-6-diamidino-2-phenylindole (DAPI) staining and transmission electron microscopy confirmed the presence of phytoplasma in some of the plants, which were also positive for this pathogen in a polymerase chain reaction (PCR) analysis. A phloem-restricted gram-negative bacteria was seen i…

The Candida albicans cell wall-associated glyceraldehyde-3-phosphate dehydrogenase activity increases in response to starvation and temperature upshi…

2002

We have determined the effect of environmental factors (mild thermal upshift and starvation) on the Candida albicans cell wall-associated glyceraldehyde-3-phosphate dehydrogenase (cwGAPDH) activity. Temperature upshift (from 28 to 37 degrees C) and/ or starvation (at 28 or 37 degrees C in water) of exponentially growing yeast cells caused an increase in cwGAPDH activity (3 to 5-, and 7 to 8-fold, respectively). This increase in activity did not correlate with an increase in the amount of cwGAPDH protein present, as determined by flow cytometry, immunoelectron microscopy and Western-blotting. These results indicate that thermal upshift and starvation cause an activation of the cwGAPDH in C. …

Motivational drivers of customer brand engagement and its effect on share of wallet in a social media context

2014

In recent years, many companies have used social media as part of their marketing and brand building activities. The rise of social media has strengthened the need for customer activation and engagement. Customer brand engagement offers companies multiple positive outcomes, such as satisfaction, trust, loyalty, and empowerment, which potentially facilitate successful business performance. The idea of engagement is relatively new in the marketing literature, and academic research has only minimally examined the potential for growth presented by engaging customers. However, numerous researchers have recognized the growing academic interest in customer brand engagement, as evidenced by the Mar…

Análisis tiempo-frecuencia de la fibrilación ventricular. Estudio experimental

2006

Introduction and objectives. The analysis of frequency variability during ventricular fibrillation has yielded inconsistent results. We used an experimental model of ventricular fibrillation, with a short timescale, to analyze variations in frequency and their associated spatial distribution. Methods. Epicardial recordings of ventricular fibrillation were made in 10 perfused isolated rabbit heart preparations using a multiple electrode system (i.e., 240 unipolar electrodes). Both spectral and time-frequency analysis were used to derive the dominant frequency in the anterolateral wall of the left ventricle. Results. Linear regression analysis showed that there was a good correlation between …