| 1. |
- Kumar, Manoj, et al.
(författare)
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An update on the nomenclature for the cellulose synthase genes in Populus
- 2009
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Ingår i: Trends in Plant Science. - : Elsevier BV. - 1360-1385 .- 1878-4372. ; 14:5, s. 248-254
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Forskningsöversikt (refereegranskat)abstract
- Cellulose synthase (CesA) is a central catalyst in the generation of the plant cell wall biomass and is, therefore, the focus of intense research. Characterization of individual CesA genes from Populus species has led to the publication of several different naming conventions for CesA gene family members in this model tree. To help reduce the resulting confusion, we propose here a new phylogeny-based CesA nomenclature that aligns the Populus CesA gene family with the established Arabidopsis thaliana CesA family structure.
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| 2. |
- Alvarez, Francisco J., et al.
(författare)
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Diverse Nitrogen Sources in Seminal Fluid Act in Synergy To Induce Filamentous Growth of Candida albicans
- 2015
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Ingår i: Applied and Environmental Microbiology. - 0099-2240 .- 1098-5336. ; 81:8, s. 2770-2780
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Tidskriftsartikel (refereegranskat)abstract
- The pathogenic fungus Candida albicans is the leading cause of vulvovaginal candidiasis (VVC). VVC represents a major quality- of-life issue for women during their reproductive years, a stage of life where the vaginal epithelium is subject to periodic hormonally induced changes associated with menstruation and concomitant exposure to serum as well as potential intermittent contact with seminal fluid. Seminal fluid potently triggers Candida albicans to switch from yeastlike to filamentous modes of growth, a developmental response tightly linked to virulence. Conversely, vaginal fluid inhibits filamentation. Here, we used artificial formulations of seminal and vaginal fluids that faithfully mimic genuine fluids to assess the contribution of individual components within these fluids to filamentation. The high levels of albumin, amino acids, and N-acetylglucosamine in seminal fluid act synergistically as potent inducers of filamentous growth, even at atmospheric levels of CO2 and reduced temperatures (30 degrees C). Using a simplified in vitro model that mimics the natural introduction of seminal fluid into the vulvovaginal environment, a pulse of artificial seminal fluid (ASF) was found to exert an enduring potential to overcome the inhibitory efficacy of artificial vaginal fluid (AVF) on filamentation. These findings suggest that a transient but substantial change in the nutrient levels within the vulvovaginal environment during unprotected coitus can induce resident C. albicans cells to engage developmental programs associated with virulent growth.
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| 3. |
- Bacete, Laura, et al.
(författare)
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Arabidopsis Response Regulator 6 (ARR6) Modulates Plant Cell-Wall Composition and Disease Resistance
- 2020
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Ingår i: Molecular Plant-Microbe Interactions. - : Scientific Societies. - 0894-0282 .- 1943-7706. ; 33:5, s. 767-780
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Tidskriftsartikel (refereegranskat)abstract
- The cytokinin signaling pathway, which is mediated by Arabidopsis response regulator (ARR) proteins, has been involved in the modulation of some disease-resistance responses. Here, we describe novel functions of ARR6 in the control of plant disease-resistance and cell-wall composition. Plants impaired in ARR6 function (arr6) were more resistant and susceptible, respectively, to the necrotrophic fungus Plectosphaerella cucumerina and to the vascular bacterium Ralstonia solanacearum, whereas Arabidopsis plants that overexpress ARR6 showed the opposite phenotypes, which further support a role of ARR6 in the modulation of disease-resistance responses against these pathogens. Transcriptomics and metabolomics analyses revealed that, in arr6 plants, canonical disease-resistance pathways, like those activated by defensive phytohormones, were not altered, whereas immune responses triggered by microbe-associated molecular patterns were slightly enhanced. Cell-wall composition of arr6 plants was found to be severely altered compared with that of wild-type plants. Remarkably, pectin-enriched cell-wall fractions extracted from arr6 walls triggered more intense immune responses than those activated by similar wall fractions from wild-type plants, suggesting that an-6 pectin fraction is enriched in wall-related damage-associated molecular patterns, which trigger immune responses. This work supports a novel function of ARR6 in the control of cell-wall composition and disease resistance and reinforces the role of the plant cell wall in the modulation of specific immune responses.
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| 4. |
- Badreddine, Ilham, et al.
(författare)
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Cell Wall Chitosaccharides Are Essential Components and Exposed Patterns of the Phytopathogenic Oomycete Aphanomyces euteiches
- 2008
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Ingår i: Eukaryotic Cell. - : American Society for Microbiology. - 1535-9778 .- 1535-9786. ; 7:11, s. 1980-1993
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Tidskriftsartikel (refereegranskat)abstract
- Chitin is an essential component of fungal cell walls, where it forms a crystalline scaffold, and chitooligosaccharides derived from it are signaling molecules recognized by the hosts of pathogenic fungi. Oomycetes are cellulosic fungus-like microorganisms which most often lack chitin in their cell walls. Here we present the first study of the cell wall of the oomycete Aphanomyces euteiches, a major parasite of legume plants. Biochemical analyses demonstrated the presence of ca. 10% N-acetyl-D-glucosamine (GlcNAc) in the cell wall. Further characterization of the GlcNAc-containing material revealed that it corresponds to noncrystalline chitosaccharides associated with glucans, rather than to chitin per se. Two putative chitin synthase (CHS) genes were identified by data mining of an A. euteiches expressed sequence tag collection and Southern blot analysis, and full-length cDNA sequences of both genes were obtained. Phylogeny analysis indicated that oomycete CHS diversification occurred before the divergence of the major oomycete lineages. Remarkably, lectin labeling showed that the Aphanomyces euteiches chitosaccharides are exposed at the cell wall surface, and study of the effect of the CHS inhibitor nikkomycin Z demonstrated that they are involved in cell wall function. These data open new perspectives for the development of antioomycete drugs and further studies of the molecular mechanisms involved in the recognition of pathogenic oomycetes by the host plants.
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| 5. |
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| 6. |
- Belmonte, Rodrigo, et al.
(författare)
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Role of Pathogen-Derived Cell Wall Carbohydrates and Prostaglandin E-2 in Immune Response and Suppression of Fish Immunity by the Oomycete Saprolegnia parasitica
- 2014
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Ingår i: Infection and Immunity. - 0019-9567 .- 1098-5522. ; 82:11, s. 4518-4529
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Tidskriftsartikel (refereegranskat)abstract
- Saprolegnia parasitica is a freshwater oomycete that is capable of infecting several species of fin fish. Saprolegniosis, the disease caused by this microbe, has a substantial impact on Atlantic salmon aquaculture. No sustainable treatment against saprolegniosis is available, and little is known regarding the host response. In this study, we examined the immune response of Atlantic salmon to S. parasitica infection and to its cell wall carbohydrates. Saprolegnia triggers a strong inflammatory response in its host (i. e., induction of interleukin-1 beta(1) [IL-1 beta(1)], IL-6, and tumor necrosis factor alpha), while severely suppressing the expression of genes associated with adaptive immunity in fish, through downregulation of T-helper cell cytokines, antigen presentation machinery, and immunoglobulins. Oomycete cell wall carbohydrates were recognized by fish leukocytes, triggering upregulation of genes involved in the inflammatory response, similar to what is observed during infection. Our data suggest that S. parasitica is capable of producing prostaglanding E-2 (PGE(2)) in vitro, a metabolite not previously shown to be produced by oomycetes, and two proteins with homology to vertebrate enzymes known to play a role in prostaglandin biosynthesis have been identified in the oomycete genome. Exogenous PGE(2) was shown to increase the inflammatory response in fish leukocytes incubated with cell wall carbohydrates while suppressing genes involved in cellular immunity (gamma interferon [IFN-gamma] and the IFN-gamma-inducible protein [gamma-IP]). Inhibition of S. parasitica zoospore germination and mycelial growth by two cyclooxygenase inhibitors (aspirin and indomethacin) also suggests that prostaglandins may be involved in oomycete development.
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| 7. |
- Bessueille, Laurence, et al.
(författare)
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A survey of cellulose biosynthesis in higher plants
- 2008
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Ingår i: PLANT BIOTECHNOLOGY. - : Japanese Society for Plant Cell and Molecular Biology. - 1342-4580 .- 1347-6114. ; 25:3, s. 315-322
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Tidskriftsartikel (refereegranskat)abstract
- Cellulose plays a central role in plant development and its biosynthesis represents one of the most important biochemical processes in plant biology. However, the corresponding molecular mechanisms are not well understood, despite the progress made in the past years in the identification of genes that code for the catalytic subunits of the cellulose synthases and other proteins potentially involved in cellulose formation. A major bottleneck is the high instability of the cellulose synthase complexes and their location in the plasma membrane. Additional efforts are currently being made to unravel the mechanisms of cellulose biosynthesis. Indeed, understanding how cellulose is formed and how its crystallinity is achieved is relevant not only for studying plant development, but also for improving the digestibility of the plant biomass, which is foreseen as an alternative to fossil fuels for the production of energy. This review summarizes the major unanswered questions related to the process of cellulose biosynthesis, and describes the recent progress that has been made in the area through the combination of biochemical approaches and molecular genetics.
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| 8. |
- Bessueille, Laurence, et al.
(författare)
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Plasma membrane microdomains from hybrid aspen cells are involved in cell wall polysaccharide biosynthesis
- 2009
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Ingår i: Biochemical Journal. - : Portland Press Ltd.. - 0264-6021 .- 1470-8728. ; 420, s. 93-103
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Tidskriftsartikel (refereegranskat)abstract
- Detergent-resistant plasma membrane microdomains [DRMs (detergent-resistant membranes)] were isolated recently from several plant species. As for animal cells, a large range of cellular functions, such as signal transduction, endocytosis and protein trafficking, have been attributed to plant lipid rafts and DRMs. The data available are essentially based on protcomics and more approaches need to be undertaken to elucidate the precise function of individual populations of DRMs in plants. We report here the first isolation of DRMs from purified plasma membranes of a tree species, the hybrid aspen Populus tremula x tremuloides, and their biochemical characterization. Plasma membranes were solubilized with Triton X-100 and the resulting DRMs were isolated by flotation in sucrose density gradients. The DRMs were enriched in sterols, sphingolipids and glycosylphosphatidylinositol-anchored proteins and thus exhibited similar properties to DRMs from other species. However, they contained key carbohydrate synthases involved in cell wall polysaccharide biosynthesis, namely callose [(1 -> 3)-beta-D-glucan] and cellulose synthases. The association of these enzymes with DRMs was demonstrated using specific glucan synthase assays and antibodies, as well as biochemical and chemical approaches for the characterization of the polysaccharides synthesized in vitro by the isolated DRMs. More than 70% of the total glucan synthase activities present in the original plasma membranes was associated with the DRM fraction. In addition to shedding light on the lipid environment of callose and cellulose synthases, our results demonstrate the involvement of DRMs in the biosynthesis of important cell wall polysaccharides. This novel concept suggests a function of plant membrane microdomains in cell growth and morphogenesis.
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| 9. |
- Betts, Natalie S., et al.
(författare)
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Identification and spatio-temporal expression analysis of barley genes that encode putative modular xylanolytic enzymes
- 2021
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Ingår i: Plant Science. - : Elsevier BV. - 0168-9452 .- 1873-2259. ; 308
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Tidskriftsartikel (refereegranskat)abstract
- Arabinoxylans are cell wall polysaccharides whose re-modelling and degradation during plant development are mediated by several classes of xylanolytic enzymes. Here, we present the identification and new annotation of twelve putative (1,4)-13-xylanase and six 13-xylosidase genes, and their spatio-temporal expression patterns during vegetative and reproductive growth of barley (Hordeum vulgare cv. Navigator). The encoded xylanase proteins are all predicted to contain a conserved carbohydrate-binding module (CBM) and a catalytic glycoside hydrolase (GH) 10 domain. Additional domains in some xylanases define three discrete phylogenetic clades: one clade contains proteins with an additional N-terminal signal sequence, while another clade contains proteins with multiple CBMs. Homology modelling revealed that all fifteen xylanases likely contain a third domain, a 13-sandwich folded from two non-contiguous sequence segments that bracket the catalytic GH domain, which may explain why the full length protein is required for correct folding of the active enzyme. Similarly, predicted xylosidase proteins share a highly conserved domain structure, each with an N-terminal signal peptide, a split GH 3 domain, and a C-terminal fibronectin-like domain. Several genes appear to be ubiquitously expressed during barley growth and development, while four newly annotated xylanase and xylosidase genes are expressed at extremely high levels, which may be of broader interest for industrial applications where cell wall degradation is necessary.
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| 10. |
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| 11. |
- Bourdon, Matthieu, et al.
(författare)
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Ectopic callose deposition into woody biomass modulates the nano-architecture of macrofibrils
- 2023
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Ingår i: Nature Plants. - : Springer Nature. - 2055-0278 .- 2055-026X. ; 9:9, s. 1530-1546
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Tidskriftsartikel (refereegranskat)abstract
- Plant biomass plays an increasingly important role in the circular bioeconomy, replacing non-renewable fossil resources. Genetic engineering of this lignocellulosic biomass could benefit biorefinery transformation chains by lowering economic and technological barriers to industrial processing. However, previous efforts have mostly targeted the major constituents of woody biomass: cellulose, hemicellulose and lignin. Here we report the engineering of wood structure through the introduction of callose, a polysaccharide novel to most secondary cell walls. Our multiscale analysis of genetically engineered poplar trees shows that callose deposition modulates cell wall porosity, water and lignin contents and increases the lignin–cellulose distance, ultimately resulting in substantially decreased biomass recalcitrance. We provide a model of the wood cell wall nano-architecture engineered to accommodate the hydrated callose inclusions. Ectopic polymer introduction into biomass manifests in new physico-chemical properties and offers new avenues when considering lignocellulose engineering.
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| 12. |
- Bouzenzana, Jamel, et al.
(författare)
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Identification of the first Oomycete annexin as a (1 -> 3)-beta-D-glucan synthase activator
- 2006
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Ingår i: Molecular Microbiology. - : Wiley. - 0950-382X .- 1365-2958. ; 62:2, s. 552-565
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Tidskriftsartikel (refereegranskat)abstract
- (1 -> 3)-beta-D-Glucans are major components of the cell walls of Oomycetes and as such they play an essential role in the morphogenesis and growth of these microorganisms. Despite the biological importance of (1 -> 3)-beta-D-glucans, their mechanisms of biosynthesis are poorly understood. Previous studies on (1 -> 3)-beta-D-glucan synthases from Saprolegnia monoica have shown that three protein bands of an apparent molecular weight of 34, 48 and 50 kDa co-purify with enzyme activity. However, none of the corresponding proteins have been identified. Here we have identified, purified, sequenced and characterized a protein from the 34 kDa band and clearly shown that it has all the biochemical properties of proteins from the annexin family. In addition, we have unequivocally demonstrated that the purified protein is an activator of (1 -> 3)-beta-D-glucan synthase. This represents a new type of function for proteins belonging to the annexin family. Two other proteins from the 48 and 50 kDa bands were identified as ATP synthase subunits, which most likely arise from contaminations by mitochondria during membrane preparation. The results, which are discussed in relation with the possible regulation mechanisms of (1 -> 3)-beta-D-glucan synthases, represent a first step towards a better understanding of cell wall polysaccharide biosynthesis in Oomycetes.
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| 13. |
- Briolay, Anne, et al.
(författare)
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Cell Wall Polysaccharide Synthases Are Located in Detergent-Resistant Membrane Microdomains in Oomycetes
- 2009
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Ingår i: Applied and Environmental Microbiology. - : American Society for Microbiology. - 0099-2240 .- 1098-5336. ; 75:7, s. 1938-1949
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Tidskriftsartikel (refereegranskat)abstract
- The pathways responsible for cell wall polysaccharide biosynthesis are vital in eukaryotic microorganisms. The corresponding synthases are potential targets of inhibitors such as fungicides. Despite their fundamental and economical importance, most polysaccharide synthases are not well characterized, and their molecular mechanisms are poorly understood. With the example of Saprolegnia monoica as a model organism, we show that chitin and (1 -> 3)-beta-D-glucan synthases are located in detergent-resistant membrane microdomains (DRMs) in oomycetes, a phylum that comprises some of the most devastating microorganisms in the agriculture and aquaculture industries. Interestingly, no cellulose synthase activity was detected in the DRMs. The purified DRMs exhibited similar biochemical features as lipid rafts from animal, plant, and yeast cells, although they contained some species-specific lipids. This report sheds light on the lipid environment of the (1 -> 3)-beta-D-glucan and chitin synthases, as well as on the sterol biosynthetic pathways in oomycetes. The results presented here are consistent with a function of lipid rafts in cell polarization and as platforms for sorting specific sets of proteins targeted to the plasma membrane, such as carbohydrate synthases. The involvement of DRMs in the biosynthesis of major cell wall polysaccharides in eukaryotic microorganisms suggests a function of lipid rafts in hyphal morphogenesis and tip growth.
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| 14. |
- Brown, Christian, 1976-
(författare)
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Characterization of specific domains of the cellulose and chitin synthases from pathogenic oomycetes
- 2015
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Some oomycetes species are severe pathogens of fish or crops. As such, they are responsible for important losses in the aquaculture industry as well as in agriculture. Saprolegnia parasitica is a major concern in aquaculture as there is currently no method available for controlling the diseases caused by this microorganism. The cell wall is an extracellular matrix composed essentially of polysaccharides, whose integrity is required for oomycete viability. Thus, the enzymes involved in the biosynthesis of cell wall components, such as cellulose and chitin synthases, represent ideal targets for disease control. However, the biochemical properties of these enzymes are poorly understood, which limits our capacity to develop specific inhibitors that can be used for blocking the growth of pathogenic oomycetes.In our work, we have used Saprolegnia monoica as a model species for oomycetes to characterize two types of domains that occur specifically in oomycete carbohydrate synthases: the Pleckstrin Homology (PH) domain of a cellulose synthase and the so-called ‘Microtubule Interacting and Trafficking’ (MIT) domain of chitin synthases. In addition, the chitin synthase activity of the oomycete phytopathogen Aphanomyces euteiches was characterized in vitro using biochemical approaches.The results from our in vitro investigations revealed that the PH domain of the oomycete cellulose synthase binds to phosphoinositides, microtubules and F-actin. In addition, cell biology approaches were used to demonstrate that the PH domain co-localize with F-actin in vivo. The structure of the MIT domain of chitin synthase (CHS) 1 was solved by NMR. In vitro binding assays performed on recombinant MIT domains from CHS 1 and CHS 2 demonstrated that both proteins strongly interact with phosphatidic acid in vitro. These results were further supported by in silico data where biomimetic membranes composed of different phospholipids were designed for interaction studies. The use of a yeast-two-hybrid approach suggested that the MIT domain of CHS 2 interacts with the delta subunit of Adaptor Protein 3, which is involved in protein trafficking. These data support a role of the MIT domains in the cellular targeting of CHS proteins. Our biochemical data on the characterization of the chitin synthase activity of A. euteiches suggest the existence of two distinct enzymes responsible for the formation of water soluble and insoluble chitosaccharides, which is consistent with the existence of two putative CHS genes in the genome of this species.Altogether our data support a role of the PH domain of cellulose synthase and MIT domains of CHS in membrane trafficking and cellular location.
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| 15. |
- Brown, Christian, et al.
(författare)
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Radiometric and spectrophotometric in vitro assays of glycosyltransferases involved in plant cell wall carbohydrate biosynthesis
- 2012
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Ingår i: Nature Protocols. - : Springer Nature. - 1754-2189 .- 1750-2799. ; 7:9, s. 1634-1650
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Tidskriftsartikel (refereegranskat)abstract
- Most of the glycosyltransferases (GTs) that catalyze the formation of plant cell wall carbohydrates remain to be biochemically characterized. This can be achieved only if specific assays are available for these enzymes. Here we present a protocol for in vitro assays of processive and nonprocessive membrane-bound GTs. The assays are either based on the use of radioactive nucleotide sugars (NDP sugars; e.g., UDP-[U-C-14] glucose) and the quantification of the radiolabeled monosaccharides incorporated into soluble or insoluble carbohydrates, or on the coupling of the GT reaction with that of pyruvate kinase (PK) and the oxidation of NADH by lactate dehydrogenase (LDH). The radiometric assays are more suitable for exploratory work on poorly characterized enzymes, whereas the spectrophotometric assays require the availability of highly enriched GTs. Both assays can be performed within 1 d, depending on the number of fractions to be assayed or reaction mixtures to be tested.
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| 16. |
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| 17. |
- Brown, Christian, et al.
(författare)
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Structural and functional characterization of the microtubule interacting and trafficking domains of two oomycete chitin synthases
- 2016
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Ingår i: The FEBS Journal. - : Wiley. - 1742-464X .- 1742-4658. ; 283:16, s. 3072-3088
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Tidskriftsartikel (refereegranskat)abstract
- Chitin synthases (Chs) are responsible for the synthesis of chitin, a key structural cell wall polysaccharide in many organisms. They are essential for growth in certain oomycete species, some of which are pathogenic to diverse higher organisms. Recently, a Microtubule Interacting and Trafficking (MIT) domain, which is not found in any fungal Chs, has been identified in some oomycete Chs proteins. Based on experimental data relating to the binding specificity of other eukaryotic MIT domains, there was speculation that this domain may be involved in the intracellular trafficking of Chs proteins. However, there is currently no evidence for this or any other function for the MIT domain in these enzymes. To attempt to elucidate their function, MIT domains from two Chs enzymes from the oomycete Saprolegnia monoica were cloned, expressed and characterized. Both were shown to interact strongly with the plasma membrane component phosphatidic acid, and to have additional putative interactions with proteins thought to be involved in protein transport and localization. Aiding our understanding of these data, the structure of the first MIT domain from a carbohydrate-active enzyme (MIT1) was solved by NMR, and a model structure of a second MIT domain (MIT2) was built by homology modelling. Our results suggest a potential function for these MIT domains in the intracellular transport and/or regulation of Chs enzymes in the oomycetes.
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| 18. |
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| 19. |
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| 20. |
- Bulone, Vincent, 1967-
(författare)
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Biosynthetic enzymes for (1,3)-β-glucans and (1,3;1,6)-β-glucans in protozoans and chromistans. biochemical characterization and molecular biology
- 2009
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Ingår i: Chemistry, biochemistry and biology of 1,3-beta-glucans and related polysaccharides. - : Elsevier. - 9780123739711 ; , s. 233-258
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Bokkapitel (refereegranskat)abstract
- This chapter discusses the biochemical characterization and molecular biology of biosynthetic enzymes for (1,3)-β-glucans and (1,3:1,6)-β-Glucans in Protozoans and Chromistans. The biosynthesis of linear β-glucans is generally considered to involve several steps. The process starts with the synthesis of an initiator of polymerization or primer, followed by the transfer of the primer to a membrane-bound synthase. The latter catalyses the repetitive transfer of glucosyl units from an activated sugar donor to the acceptor-i.e. the primer or the elongating chain-until the polymerization stops. Most molecular events occurring during the biosynthesis of (1,3)-β-glucans and (1,3;1,6)-β-Glucans in Protozoans and Chromistans are not well understood. The process for which most biochemical data have been accumulated is the polymerization of linear (1,3)-β-glucan chains. The ability to synthesize β-glucans in vitro represents a very useful tool for assaying glucan synthases during enzyme purification. This is also useful in identifying the type of effectors that might influence enzyme activity in vivo and thus regulate the biosynthesis of the polysaccharides.
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| 21. |
- Bulone, Vincent
(författare)
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Cellulose biosynthesis in higher plants
- 2011
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Ingår i: Abstracts of Papers of the American Chemical Society. - 0065-7727. ; 241
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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| 22. |
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| 23. |
- Bulone, Vincent, et al.
(författare)
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Characterisation of horse dander allergen glycoproteins using amino acid and glycan structure analyses - A mass spectrometric method for glycan chain analysis of glycoproteins separated by two-dimensional electrophoresis
- 2000
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Ingår i: International Archives of Allergy and Immunology. - : S. Karger AG. - 1018-2438 .- 1423-0097. ; 123:3, s. 220-227
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Tidskriftsartikel (refereegranskat)abstract
- Separation of horse dander allergens using two-dimensional PAGE resulted in the identification of 16 proteins that react with allergic patient sera. A sensitive method has been developed for analysing the structures of the glycan chains of individual glycoprotein allergens transferred to blots following two-dimensional PAGE, and has allowed the structural identification of the glycan chains of the most abundant isoforms of Equ c 1, a glycosylated horse dander major allergen. The method involves separation of the allergens by two-dimensional PAGE, transfer to polyvinylidene difluoride membranes, release of the glycan chains using peptide N-glycosidase F, permethylation and mass spectrometric analysis of the derivatised glycans. The amino acid compositions of the 16 horse dander allergens separated by two-dimensional PAGE have been determined, allowing the identification of the various isoforms of Equ c 1. These results also confirmed that the two non-glycosylated major allergens, Equ c 2.0101 and Equ c 2.0102, belong to the lipocalin family, and support the idea that these two allergens are most probably isoforms of the same protein. The glycan structures identified using the mass spectrometric method are common biantennary and triantennary glycan chains. These carbohydrate moieties may have a role in the binding of IgE; however, it is more likely that the overall glycoprotein structure involving both the glycan and protein moieties, rather than the structure of the glycan chains alone, is responsible for eliciting allergic responses.
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| 24. |
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| 25. |
- Bulone, Vincent, 1967-, et al.
(författare)
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Methods for manufacturing plant cell walls comprising chitin
- 2010
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Patent (populärvet., debatt m.m.)abstract
- Methods and means are provided for the modification of the reactivity of plant secondary cell walls, particularly in cotton cell walls found in cotton fibers. This can be conveniently achieved by expressing a chimeric gene encoding a Saprolegnia monoica chitin synthase in cotton plants.
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