Cell wall

Demonstrating the main chemical constituents of Anodendron paniculatum (Roxb.) A.DC. Structural determination of isolated compounds; evaluation of the cytotoxic activities of isolated compounds against human cancer cell lines.

25p nguathienthan12 23-05-2021 13 3   Download

Grain weight (GW) is a key component of sunflower yield and quality, but may be limited by maternal tissues. Cell growth is influenced by expansin proteins that loosen the plant cell wall.

14p vishikamaru2711 29-04-2020 11 1   Download

Agrobacterium tumefaciens is a Gram-negative, phytopathogenic bacterium and is characterized by an unique mode of action on dicotyledonous plants: it is able to genetically modify the host, and because of this feature, it is used as a tool for transgenic plants. Many experiments have demonstrated that lipopolysaccharides (LPSs) play an important role for the disease development, as they are involved in the adhesion process of the bacterium on the plant cell wall.

4p system191 01-06-2013 32 4   Download

Expansins are a family of proteins that catalyze pHdependent long-term extension of isolated plant cell walls. They are divided into two groups, a and b, the latter consisting of the grass group I pollen allergens and their vegetative homologs. Expansins are suggested to mediate plant cell growth by interfering with either structural proteins or the polysaccharide network in the cell wall.

10p research12 01-06-2013 28 4   Download

Plant cell wall proteins called expansins are thought to disrupt hydrogen bonding between cell wall polysaccha-rides without hydrolyzing them. We describe here a novel gene with sequence similarity to plant expansins, isolated from the cellulolytic fungus Trichoderma reesei. The pro-tein named swollenin has an N-terminal fungal type cel-lulose binding domain connected by a linker region to the expansin-like domain.

10p research12 23-04-2013 35 4   Download

Wehave examined the effectsof three ring-sizeanalogsof the cyclicb-sheet antimicrobial peptidegramicidinS (GS) on the thermotropic phase behavior and permeability of phos-pholipid model membranes and on the growth of the cell wall-less Gram-positive bacteriaAcholeplasma laidlawiiB. These three analogs have ring sizes of 10 (GS10), 12 (GS12) or 14 (GS14) amino acids, respectively.

10p tumor12 22-04-2013 32 2   Download

Structures of cell wall anionic polymers of the strainStrep-tomycessp. VKMAc-2124, a causative agent of potato scab, which is phylogenetically the closest to plant pathogenic speciesS. setoniiandS. caviscabies, were studied. The strain contains threeanionicglycopolymers, viz., a teichuronicacid with a disaccharide repeatingunitfi6)-a-D-Glcp-(1fi4)-b-D-ManpNAc3NAcA-(1fi,ab-glucosylated polymer of 3-deoxy-D-glycero-D-galacto-non-2-ulopyranosonic acid (Kdn), and ab-glucosylated 1,5-poly(ribitol phosphate). ...

6p tumor12 22-04-2013 36 4   Download

Previously, we isolated a 4-kDa peptide capable of binding to a 43-kDa receptor-like protein and stimulating protein kinase activity of the 43-kDa protein in soybean. Both of them were found to localize in the plasma membranes and cell walls. Here, we report the physiological effects of 4-kDa peptide expressed transiently in the cultured carrot and bird’s-foot trefoil cells transfected with pBI 121 plas-mid containing the 4-kDa peptide gene.

8p tumor12 20-04-2013 43 4   Download

Tip growth is a specialized type of polar growth where new cell wall is deposited in a localized region of the cell, the growing tip. These cells show a characteristic zonation, with a high accumulationof secretory vesicles containing cell wall components at the tip, followed by an organelle-enriched zone.MsPG3is a Medicago sativapolygalacturonase gene isolated in our laboratory, specifically expressed during the interaction of this plant with its symbiotic partner Sinorhiz-obium melilotiand which might participate in tip growth processes during symbiosis....

9p tumor12 20-04-2013 41 3   Download

Cells that have lost the ability to grow in culture could be defined operationally as either alive or dead depending on the method used to determine cell viability. As a conse-quence, the interpretation of the state of
nonculturablecells is often ambiguous.Escherichia coliK12 cells inactivated by UV-irradiation with a low (UV1) and a high (UV2) dose wereusedas amodel of nonculturable cells. Cells inactivated by the UV1 dose lost
culturability but they were not lysed andmaintained the capacity to respond to nutrient addition by protein synthesis and cell wall synthesis. ...

7p fptmusic 16-04-2013 23 2   Download

The antigenicity ofCandida lusitaniaecells was found to be thesameasthatof Candida albicansserotype A cells, i.e. both cell wall mannans react with factors 1, 4, 5, and 6 sera of Candida Check. However, the structure of the mannan of C. lusitaniaewas significantly different from that of C. albicansserotype A, and we found novelb-1,2 linkages among the side-chainoligosaccharides,Manb1fi2Manb1fi 2Mana1fi2Mana1fi2Man (LM5), and Manb1fi2Man-b1fi2Manb1fi2Mana1fi2Mana1fi2Man (LM6).

11p fptmusic 16-04-2013 55 6   Download

Streptococcus mitisstrain SK598, which represents a sub-group of biovar 1, possesses a unique variant of the C-polysaccharide found in the cell wall of all strains of Streptococcus pneumoniaeand in some strains ofS. mitis. This newvariant lacks the cholinemethyl groups in contrast to the previously characterized forms of C-polysaccharide, whichall containone or two choline residues per repeat. The following structure of the repeating unit of the SK598 polysaccharide was established: where AAT is 2-acetamido-4-amino-2,4,6-trideoxy-D-galactose....

6p fptmusic 16-04-2013 28 2   Download

Feruloyl esterases hydrolyse phenolic groups involved in the cross-linking of arabinoxylan to other polymeric structures. This is important for open-ing the cell wall structure making material more accessible to glycoside hydrolases. Here we describe the crystal structure of inactive S133A mutant of type-A feruloyl esterase fromAspergillus niger(AnFaeA) in complex with a feruloylated trisaccharide substrate.

10p fptmusic 11-04-2013 43 1   Download

A new component of theb-1,6-glucanase (EC 3.2.1.75) multienzymatic complex secreted by Trichoderma harzianumhas been identified and fully characterized. The protein, namely BGN16.3, is the third isozyme display-ing endo-b-1,6-glucanase activity described up to now in T. harzianum CECT 2413. BGN16.3 is an acidicb-1,6-glucanase that is specifically induced by the presence of fungal cell walls in T. harzianumgrowth media.

8p fptmusic 11-04-2013 29 2   Download

Oxysterols, and particularly 7-ketocholesterol, appear to be strongly involved in the physiopathology of atherosclerosis. These molecules are suspected to be cytotoxic to the cells of the vascular wall and mono-cytes⁄macrophages, particularly by inducing apoptosis. Previous studies have demonstrated that 7-ketocholesterol-induced apoptosis is triggered by a sustained increase of cytosolic-free Ca 2+ , which elicits the mitochondrial pathway of apoptosis by activation of the calcium-dependent phosphatase calcineurin, leading to dephosphorylation of the ‘BH3 only’ protein BAD....

12p fptmusic 11-04-2013 33 2   Download

The surface charge as well as the electrochemical properties and ligand binding abilities of the Gram-positive cell wall is controlled by the d-alanylation of the lipoteichoic acid. The incorporation of d-Ala into lipoteichoic acid requires the d-alanine:d-alanyl carrier protein ligase (DltA) and the carrier protein (DltC). We have heterologously expressed, purified, and assayed the substrate selectivity of the recombinant proteins DltA with its substrate DltC.

11p awards 06-04-2013 39 5   Download

Addition of the second mannose is the only obvious step in glycosylphos-phatidylinositol (GPI) precursor assembly for which a responsible gene has not been discovered. A bioinformatics-based strategy identified the essential Saccharomyces cerevisiaeYbr004c protein as a candidate for the second GPIa-mannosyltransferase (GPI-MT-II). S. cerevisiae cells depleted of Ybr004cp have weakened cell walls and abnormal morphology, are unable to incorporate [ 3 H]inositol into proteins, and accumulate a GPI intermedi-ate having a single mannose that is likely modified with ethanolamine phosphate. ...

9p awards 05-04-2013 30 2   Download

Trichodermaspecies have been investigated as biological control agents for over 70 years owing to their ability to antagonize plant pathogenic fungi. Mycoparasitism, one of the main mechanisms involved in the antagonistic activity ofTrichodermastrains, depends on the secretion of complex mix-tures of hydrolytic enzymes able to degrade the host cell wall. The antifun-gal activity of an a-1,3-glucanase (EC 3.2.1.59, enzymes able to degrade a-1,3-glucans and also named mutanases) has been described in T. harzia-num and its role in mycoparasitic processes has been suggested....

0p awards 05-04-2013 43 4   Download

Gas1p is a glycosylphosphatidylinositol-anchored plasma membrane glycoprotein ofSaccharomyces cerevisiaeand is a representative of Family GH72 of glycosidases/transgly-cosidases, which also includes proteins from human fungal pathogens. Gas1p, Phr1-2p from Candida albicansand Gel1p fromAspergillus fumigatushave been shown to be b-(1,3)-glucanosyltransferases required for proper cell wall assembly andmorphogenesis. Gas1p is organized into three modules: a catalytic domain; a cys-richdomain; andahighly O-glycosylated serine-rich region. ...

11p awards 05-04-2013 47 4   Download

Lipid peroxidation and its products such as 4-hydroxy-2-nonenal (HNE) and 4-hydroxyhexenal (HHE) are known to affect redox balance duringagingand various degenerative processes, includingvascular dysfunction. Deterioration of the endothelial cells that line the vascular wall is known to be an underlyingcause of vascular dysfunction. At present, little is known about themechanismbywhichHHE induces endothelial cell death (i.e. apoptosis), although HNE-induced apoptotic cell death has been reported. ...

9p dell39 03-04-2013 25 3   Download