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Margolin William W Department of Microbiology and Molecular Genetics, University of Texas Medical School at Houston, 6431 Fannin Street, Houston, TX 77030, USA. - - 2009
Prokaryotes come in a wide variety of shapes, determined largely by natural selection, physical constraints, and patterns of cell growth and division. Because of their relative simplicity, bacterial cells are excellent models for how genes and proteins can directly determine morphology. Recent advances in cytological methods for bacteria have shown ...
Baker Lorina G LG Department of Molecular Microbiology, Washington University School of Medicine, 660 S. Euclid Avenue, Campus Box 8230, St. Louis, MO 63104, - - 2009
Cryptococcus neoformans is an opportunistic pathogen that mainly infects immunocompromised individuals. The fungal cell wall of C. neoformans is an excellent target for antifungal therapies since it is an essential organelle that provides cell structure and integrity. Importantly, it is needed for localization or attachment of known virulence factors, including ...
Rüggeberg Markus - - 2010
The culms of the giant reed Arundo donax represent slender tube-like structures. Several nodes along the culm, a ring of sclerenchymatous fibres in the periphery of the culm wall and numerous isolated vascular bundles enclosed by fibre rings in the culm wall function as stiffening elements. The bundles are embedded ...
Abasolo Willie - - 2009
Plant cell walls, like a multitude of other biological materials, are natural fiber-reinforced composite materials. Their mechanical properties are highly dependent on the interplay of the stiff fibrous phase and the soft matrix phase and on the matrix deformation itself. Using specific Arabidopsis thaliana mutants, we studied the mechanical role ...
Rijavec Tomaz - - 2009
We report here on a comparative developmental profile of plant hormone cytokinins in relation to cell size, cell number and endoreduplication in developing maize caryopsis of a cell wall invertase-deficient miniature1 (mn1) seed mutant and its wild type, Mn1, genotype. Both genotypes showed extremely high levels of total cytokinins during ...
Aouar Leila - - 2010
Cellulose is the principal component of the load-bearing system in primary plant cell walls. The great resistance to tensile forces of this polysaccharide and its embedding in matrix components make the cell wall a material similar to a fiber composite. In the rapidly growing pollen tube, the amount of cellulose ...
de O Buanafina Marcia M - - 2009
In the cell walls of forage grasses, ferulic acid is esterified to arabinoxylans and participates with lignin monomers in oxidative coupling pathways to generate ferulate-polysaccharide-lignin complexes that cross-link the cell wall. The accumulation of ferulates and the cross-linking of arabinoxylans via diferulate esters are hypothesized to function in various processes ...
Domozych David S - - 2009
The production of multicellular gametangia in green plants represents an early evolutionary development that is found today in all land plants and advanced clades of the Charophycean green algae. The processing of cell walls is an integral part of this morphogenesis yet very little is known about cell wall dynamics ...
Tesson Benoit - - 2009
Among diatoms, Phaeodactylum tricornutum is a peculiar species that exists in three morphotypes with distinct cell wall structures and low silica content. X-ray photoelectron spectroscopy (XPS) analysis was performed on P. tricornutum and compared with diatom Thalassiosira pseudonana; the results provide new information on the chemical composition (elements, chemical functions, ...
Zerzour Rabah - - 2009
Cellular morphogenesis involves changes to cellular size and shape which in the case of walled cells implies the mechanical deformation of the extracellular matrix. So far, technical challenges have made quantitative mechanical measurements of this process at subcellular scale impossible. We used micro-indentation to investigate the dynamic changes in the ...
Skovierová Henrieta H Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523-1682, - - 2009
Arabinogalactan (AG) and lipoarabinomannan (LAM) are the two major cell wall (lipo)polysaccharides of mycobacteria. They share arabinan chains made of linear segments of alpha-1,5-linked D-Araf residues with some alpha-1,3-branching, the biosynthesis of which offers opportunities for new chemotherapeutics. In search of the missing arabinofuranosyltransferases (AraTs) responsible for the formation of ...
Krzes??owska Magdalena - - 2010
The hypothesis that lead (Pb) can be uptake or remobilized from the cell wall (CW) by internalization withlow-esterified pectins (up to 40%--JIM5-P), was studied in tip-growing apical cell of Funaria hygrometrica protonemata. Treatment 4h with 1mM PbCl(2) caused marked vesicular traffic intensification and the common internalization of JIM5-P from the ...
Sekiya Mizuho - - 2009
The cell wall integrity checkpoint coordinates cell wall synthesis and mitosis in the budding yeast, Saccharomyces cerevisiae. It has been reported that this checkpoint arrests the cell cycle at G2/M phase with repression of the M phase cyclin Clb2p at the transcriptional level, under perturbation of cell wall synthesis. We ...
Schirner Kathrin - - 2009
The prokaryotic cytoskeletal protein MreB is thought to govern cell shape by positioning the cell wall synthetic apparatus at growth sites in the cell. In rod-shaped bacteria it forms helical filaments that run around the periphery of the rod during elongation. Gram-positive bacteria often contain more than one mreB gene. ...
Brunner Eike - - 2009
Diatoms have continued to attract research interest over a long time. One important reason for this research interest is the amazingly beautiful microstructured and nanostructured patterning of the silica-based diatom cell walls. These materials become increasingly important from the materials science point of view. However, many aspects of diatom cell ...
Lennartsson Patrik R - - 2009
The dimorphic fungus Mucor indicus was grown in different forms classified as purely filamentous, mostly filamentous, mostly yeast-like and purely yeast-like, and the relationship between morphology and metabolite production, inhibitor tolerance and the cell wall composition was investigated. Low concentrations of spores in the inoculum with subsequent aeration promoted filamentous ...
Coleman Heather D - - 2009
Overexpression of the Gossypium hirsutum sucrose synthase (SuSy) gene under the control of 2 promoters was examined in hybrid poplar (Populus alba x grandidentata). Analysis of RNA transcript abundance, enzyme activity, cell wall composition, and soluble carbohydrates revealed significant changes in the transgenic lines. All lines showed significantly increased SuSy ...
Gomez Leonardo D - - 2009
Arabinans are found in the pectic network of many cell walls, where, along with galactan, they are present as side chains of Rhamnogalacturonan l. Whilst arabinans have been reported to be abundant polymers in the cell walls of seeds from a range of plant species, their proposed role as a ...
Fonseca Fernanda L - - 2009
Molecules composed of beta-1,4-linked N-acetylglucosamine (GlcNAc) and deacetylated glucosamine units play key roles as surface constituents of the human pathogenic fungus Cryptococcus neoformans. GlcNAc is the monomeric unit of chitin and chitooligomers, which participate in the connection of capsular polysaccharides to the cryptococcal cell wall. In the present study, we ...
Ordaz-Ortiz Jos?? J - - 2009
Methods developed to isolate intact cells from both unripe and ripe tomato fruit pericarp parenchyma have allowed the cell biological analysis of polysaccharide epitopes at the surface of separated cells. The LM7 pectic homogalacturonan epitope is a marker of the junctions of adhesion planes and intercellular spaces in parenchyma systems. ...
Dean Mason N - - 2009
The majority of the skeleton of elasmobranch fishes (sharks, rays and relatives) is tessellated: uncalcified cartilage is overlain by a superficial rind of abutting, mineralized, hexagonal blocks called tesserae. We employed a diversity of imaging techniques on an ontogenetic series of jaw samples to investigate the development of the tessellated ...
Kitamura Akihiro - - 2009
Beta-1,6-glucan is a fungus-specific cell wall component that is essential for the retention of many cell wall proteins. We recently reported the discovery of a small molecule inhibitor of beta-1,6-glucan biosynthesis in yeasts. In the course of our study of its derivatives, we found a unique feature in their antifungal ...
Hedenstr??m Mattias - - 2009
2D 13C-(1)H HSQC NMR spectroscopy of acetylated cell walls in solution gives a detailed fingerprint that can be used to assess the chemical composition of the complete wall without extensive degradation. We demonstrate how multivariate analysis of such spectra can be used to visualize cell wall changes between sample types ...
Gilbert Louise - - 2009
The GDP-D-mannose 3,5-epimerase (GME, EC 5.1.3.18), which converts GDP-d-mannose to GDP-l-galactose, is generally considered to be a central enzyme of the major ascorbate biosynthesis pathway in higher plants, but experimental evidence for its role in planta is lacking. Using transgenic tomato lines that were RNAi-silenced for GME, we confirmed that ...
Obel Nicolai - - 2009
Oligosaccharide Mass Profiling (OLIMP) allows a fast and sensitive assessment of cell wall polymer structure when coupled with Matrix Assisted Laser Desorption Ionisation Time Of Flight Mass Spectrometry (MALDI-TOF MS). The short time required for sample preparation and analysis makes possible the study of a wide range of plant organs, ...
Fang Wenxia - - 2009
Phosphomannose isomerase (PMI) is an enzyme catalysing the interconversion of mannose 6-phosphate (Man-6-P) and fructose 6-phosphate (Fru-6-P). The reaction catalysed by PMI is the first committed step in the synthesis of mannose-containing sugar chains and provides a link between glucose metabolism and mannosylation. In this study, the pmi1 gene was ...
Fan Ling - - 2009
The mature cotton (Gossypium hirsutum L.) fiber is a single cell with a typically thickened secondary cell wall. The aim of this research was to use molecular, spectroscopic and chemical techniques to investigate the possible occurrence of previously overlooked accumulation of phenolics during secondary cell wall formation in cotton fibers. ...
Jin Ye - - 2009
Invertase plays multiple pivotal roles in plant development. Thus, its activity must be tightly regulated in vivo. Emerging evidence suggests that a group of small proteins that inhibit invertase activity in vitro appears to exist in a wide variety of plants. However, little is known regarding their roles in planta. ...
Sujith Athiyanathil - - 2009
The surface of a living yeast cell (Saccharomyces cerevisiae strain W303-1A) has been labeled with silver (Ag) nanoparticles that can form nanoaggregates which have been shown to have surface-enhanced Raman scattering (SERS) activity. The cell wall of a single living yeast cell has been imaged by use of a Raman ...
Grijpstra Jan - - 2009
The human pathogen Cryptococcus neoformans causes meningoencephalitis. The polysaccharide capsule is one of the main virulence factors and consists of two distinct polysaccharides, glucuronoxylomannan (GXM) and galactoxylomannan (GalXM). How capsular polysaccharides are synthesized, transported, and assembled is largely unknown. Previously, it was shown that mutations in the CAP10, CAP59, CAP60, ...
Van de Wouw Angela P - - 2009
Maintaining cell wall integrity is essential for fungal growth and development. We describe two mutants with altered expression of a gene, LmIFRD, from the ascomycete Leptosphaeria maculans. Truncation of the LmIFRD transcript in a T-DNA insertional mutant led to slower germination, less sporulation and loss-of-pathogenicity towards Brassica napus, whereas silencing ...
Asaduzzaman Sikder M - - 2009
We determined the mode of action of nukacin ISK-1. It did not cause membrane potential dissipation or the efflux of ATP or K(+) ions from the cells of a sensitive bacterial strain; however, it blocked the membrane depolarization activity of nisin. Nukacin ISK-1-treated cells had single arrangements of cells without ...
Riveline Daniel - - 2009
Yeast is a powerful genetic model system, but its rigid cell wall has prohibited microinjection. Using microfabricated channels to constrain the fission yeast Schizosaccharomyces pombe, we sheared local regions of individual cells with a piezoelectric unit. The cells remained viable, we detected actin patches in the cell after introduction of ...
Birkaya Barbara - - 2009
Many fungal species including pathogens exhibit filamentous growth (FG) as a means of foraging for nutrients. Genetic screens were performed to identify genes required for FG in the budding yeast Saccharomyces cerevisiae. Genes encoding proteins with established functions in transcriptional activation (MCM1, MATalpha2, PHD1, MSN2, SIR4, and HMS2), cell wall ...
Minc Nicolas N Department of Microbiology, Columbia University College of Physicans and Surgeons, 701 W 168th Street, New York, NY 10032, - - 2009
Mechanical properties contribute to the control of cell size, morphogenesis, development, and lifestyle of fungal cells. Tip growth can be understood by a viscoplastic model, in which growth is derived by high internal turgor pressure and cell-wall elasticity. To understand how these properties regulate growth in the rod-shaped fission yeast ...
Kaida Rumi - - 2009
Wall-bound purple acid phosphatases have been shown to be potentially involved in the regulation of plant cell growth. The aim of this work was to further investigate the function of one of these phosphatases in tobacco (Nicotiana tabacum), NtPAP12, using transgenic cells overexpressing the enzyme. The transgenic cells exhibited a ...
Müller Kerstin - - 2009
Loosening of cell walls is an important developmental process in key stages of the plant life cycle, including seed germination, elongation growth, and fruit ripening. Here, we report direct in vivo evidence for hydroxyl radical ((*)OH)-mediated cell wall loosening during plant seed germination and seedling growth. We used electron paramagnetic ...
Dibley Stephen J - - 2009
Transfer cells (TCs) trans-differentiate from differentiated cells by developing extensive wall ingrowths that enhance plasma membrane transport of nutrients. Here, we investigated transcriptional changes accompanying induction of TC development in adaxial epidermal cells of cultured Vicia faba cotyledons. Global changes in gene expression revealed by cDNA-AFLP were compared between adaxial ...
Aydar Ebru - - 2009
Eukaryotic cells can sense a wide variety of environmental stresses, including changes in temperature, pH, osmolarity and nutrient availability. They respond to these changes through a variety of signal-transduction mechanisms, including activation of Ca(2+)-dependent signaling pathways. This research has discovered important implications in the function(s) of polycystic kidney disease (PKD) ...
Gastebois Amandine - - 2009
Aspergillus fumigatus is the most prevalent thermophilic inhabitants of decaying vegetation and one of the most important human opportunistic fungal pathogens. Like other fungi, A. fumigatus cells are covered by a cell wall, which is both a protective, rigid exoskeleton and a dynamic structure, undergoing constant modification depending on its ...
Shibaya Taeko - - 2009
Arabinogalactan proteins (AGPs) are abundant plant cell surface proteoglycans widely distributed in plant species. Since high concentrations of beta-glucosyl Yariv reagent (betaglcY), which binds selectively to AGPs, inhibited cell division of protoplast-regenerated cells of the liverwort Marchantia polymorpha L. (Shibaya and Sugawara in Physiol Plant 130:271-279, 2007), we investigated the ...
Cheng Crystal - - 2009
Multi-walled carbon nanotubes (MWNTs) have been proposed for use in many applications and concerns about their potential effect on human health have led to the interest in understanding the interactions between MWNTs and human cells. One important technique is the visualisation of the intracellular distribution of MWNTs. We exposed human ...
Lin Chun - - 2009
The possible toxicities of agglomerates of multi-walled carbon nanotubes (MWCNTs) toward plant cells were evaluated. Arabidopsis T87 suspension cells were used as the model cells and decreases in values of cell dry weights, cell viabilities, cell chlorophyll contents, and superoxide dismutase (SOD) activities were seen for the cells cultured in ...
Gao Peng - - 2009
Mycobacterium tuberculosis and nonpathogenic bacteria, Corynebacterium glutamicum, possess a common and unusual cell wall architecture. A cell-based screening system was designed to identify novel compounds interacting with the synthesis, assembly or regulation of the M. tuberculosis cell wall. C. glutamicum was tested in a paired medium assay in 96-well plates ...
Durand Caroline - - 2009
Border-like cells are released by Arabidopsis (Arabidopsis thaliana) root tips as organized layers of several cells that remain attached to each other rather than completely detached from each other, as is usually observed in border cells of many species. Unlike border cells, cell attachment between border-like cells is maintained after ...
Corson Francis - - 2009
The forms resulting from growth processes are highly sensitive to the nature of the driving impetus, and to the local properties of the medium, in particular, its isotropy or anisotropy. In turn, these local properties can be organized by growth. Here, we consider a growing plant tissue, the shoot apical ...
Hübscher Judith - - 2009
MsrR, a factor contributing to methicillin resistance in Staphylococcus aureus, belongs to the LytR-CpsA-Psr family of cell envelope-associated proteins. Deletion of msrR increased cell size and aggregation, and altered envelope properties, leading to a temporary reduction in cell surface hydrophobicity, diminished colony-spreading ability, and an increased susceptibility to Congo red. ...
Gorocica Patricia - - 2009
Histoplasma capsulatum is an intracellular fungal pathogen that causes respiratory and systemic disease by proliferating within phagocytic cells. The binding of H. capsulatum to phagocytes may be mediated by the pathogen's cell wall carbohydrates, glucans, which consist of glucose homo and hetero-polymers and whose glycosydic linkage types differ between the ...
Hakenbeck Regine - - 2009
The pneumococcal choline-containing teichoic acids are targeted by cholinebinding proteins (CBPs), major surface components implicated in the interaction with host cells and bacterial cell physiology. CBPs also occur in closely related commensal species, Streptococcus oralis and Streptococcus mitis, and many strains of these species contain choline in their cell wall. ...
Fukuda Kazuharu - - 2009
Class III chitin synthases play important roles in tip growth and conidiation in many filamentous fungi. However, little is known about their functions in those processes. To address these issues, we characterized the deletion mutant of a class III chitin synthase-encoding gene of Aspergillus nidulans, chsB, and investigated ChsB localization ...
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