| 1. |
- Falck, Peter, et al.
(författare)
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Xylooligosaccharides from Hardwood and Cereal Xylans Produced by a Thermostable Xylanase as Carbon Sources for Lactobacillus brevis and Bifidobacterium adolescentis.
- 2013
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Ingår i: Journal of Agricultural and Food Chemistry. - : American Chemical Society (ACS). - 0021-8561 .- 1520-5118. ; 61:30, s. 7333-7340
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Tidskriftsartikel (refereegranskat)abstract
- To compare xylans from forestry with agricultural origins, hardwood xylan (birch) and cereal arabinoxylan (rye) were hydrolyzed using two variants of the xylanase RmXyn10A, full-length enzyme and catalytic module only, from Rhodothermus marinus . Cultivations of four selected bacterial species, using the xylooligosaccharide (XOS) containing hydrolysates as carbon source, showed selective growth of Lactobacillus brevis DSMZ 1264 and Bifidobacterium adolescentis ATCC 15703. Both strains were confirmed to utilize the XOS fraction (DP 2-5), whereas putative arabinoxylooligosaccharides from the rye arabinoxylan hydrolysate were utilized by only B. adolescentis. Escherichia coli did not grow, despite its capability to grow on the monosaccharides arabinose and xylose. It was also shown that Pediococcus parvulus strain 2.6 utilized neither xylose nor XOS for growth. In summary, RmXyn10A or its catalytic module proved suitable for high-temperature hydrolysis of hardwood xylan and cereal arabinoxylan, producing XOS that could qualify as prebiotics for use in functional food products.
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| 2. |
- Immerzeel, Peter, et al.
(författare)
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Extraction of water-soluble xylan from wheat bran and utilization of enzymatically produced xylooligosaccharides by Lactobacillus, Bifidobacterium and Weissella spp.
- 2014
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Ingår i: LWT - Food Science and Technology. - : Elsevier BV. - 0023-6438. ; 56:2, s. 321-327
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Tidskriftsartikel (refereegranskat)abstract
- Xylan was extracted from wheat bran after heat pretreatment in water using either an autoclave or a microwave oven. Xylooligosaccharides (XOS) were produced from the xylan using the thermostable xylanase RmXyn10A and the potential prebiotic properties of XOS were studied in vitro with different human gut bacteria: Lactobacillus brevis (DSMZ 1269), Bifidobacterium adolescentis (ATCC 15703) and two strains of recently isolated lactic acid bacteria from the species pair Weissella cibaria/confusa. The highest yield of (arabino)xylan with the heat pretreatment was obtained at 185 degrees C for 10 min. Higher temperature led to fewer arabinose substitutions present on the backbone which in turn resulted in a slightly more efficient enzymatic hydrolysis by RmXyn10A. Using the produced XOS hydrolysate as carbon source, xylobiose uptake was confirmed for all bacterial species studied while xylotriose uptake could be confirmed for B. adolescentis and the Weissella strains. The negative control strain Escherichia coli (BL 21) did not use XOS as a carbon source. L brevis, B. adolescentis and the Weissella spp. all showed growth on XOS, verified by increases in cell density, lactic acid and acetic acid production after 48 h incubation. Corresponding increases were not found using the non-hydrolysed xylan as carbon source. (C) 2013 Elsevier Ltd. All rights reserved.
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| 3. |
- Miranda, Hélder, et al.
(författare)
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Sll1783, a monooxygenase associated with polysaccharide processing in the unicellular cyanobacterium Synechocystis PCC 6803
- 2017
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Ingår i: Physiologia Plantarum. - : Wiley. - 0031-9317 .- 1399-3054. ; 161:2, s. 182-195
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Tidskriftsartikel (refereegranskat)abstract
- Cyanobacteria play a pivotal role as the primary producer in many aquatic ecosystems. The knowledge on the interacting processes of cyanobacteria with its environment - abiotic and biotic factors - is still very limited. Many potential exocytoplasmic proteins in the model unicellular cyanobacterium Synechocystis PCC 6803 have unknown functions and their study is essential to improve our understanding of this photosynthetic organism and its potential for biotechnology use. Here we characterize a deletion mutant of Synechocystis PCC 6803, Δsll1783, a strain that showed a remarkably high light resistance which is related with its lower thylakoid membrane formation. Our results suggests Sll1783 to be involved in a mechanism of polysaccharide degradation and uptake and we hypothesize it might function as a sensor for cell density in cyanobacterial cultures.
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| 4. |
- Patel, Ami, et al.
(författare)
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Evidence for xylooligosaccharides utilization in Weissella strains isolated from Indian fermented foods and vegetables.
- 2013
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Ingår i: FEMS Microbiology Letters. - : Oxford University Press (OUP). - 1574-6968 .- 0378-1097. ; 346:1, s. 20-28
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Six strains isolated from fermented food were by 16S rDNA sequencing identified as Weissella species, clustering with the species-pair W. confusa/ W. cibaria. The strains were analysed for growth on glucose, xylose and xylooligosaccharides (XOS). All strains were xylose positive using the API CHL 50 test. Growth on XOS was observed for strain 85, 92, 145 and AV1, firstly by optical density measurements in microtiter plates and secondly in batch cultures also confirming concomitant decrease in pH. Analysis of XOS before and after growth established consumption in the DP2 - DP5 range in the four XOS-fermenting strains. XOS were consumed simultaneously with glucose, while xylose was consumed after glucose depletion. Cell-associated β-xylosidase activity was detected in the XOS fermenting strains. Analysis of genomic data suggests this activity to be linked to genes encoding glycoside hydrolases from family 3, 8 or 43. No endo-β-xylanase activity was detectable. Main fermentation end products were lactate and acetate. A higher ratio of acetic acid/lactic acid was produced during growth on XOS compared to growth on glucose. This is the first report on utilization of XOS in Weissella, indicating an increased probiotic potential for XOS-utilizing strains from the species pair W. confusa/ W. cibaria, but also showing that XOS utilization is strain-dependent for these species. This article is protected by copyright. All rights reserved.
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| 5. |
- Takahashi Schmidt, Junko, et al.
(författare)
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KORRIGAN1 and its Aspen Homolog PttCel9A1 Decrease Cellulose Crystallinity in Arabidopsis Stems
- 2009
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Ingår i: Plant and Cell Physiology. - : Oxford University Press (OUP). - 0032-0781 .- 1471-9053. ; 50:6, s. 1099-1115
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Tidskriftsartikel (refereegranskat)abstract
- KORRIGAN1 (KOR1) is a membrane-bound cellulase implicated in cellulose biosynthesis. PttCel9A1 from hybrid aspen (Populus tremula L. tremuloides Michx.) has high sequence similarity to KOR1 and we demonstrate here that it complements kor1-1 mutants, indicating that it is a KOR1 ortholog. We investigated the function of PttCel9A1/KOR1 in Arabidopsis secondary growth using transgenic lines expressing 35S::PttCel9A1 and the KOR1 mutant line irx2-2. The presence of elevated levels of PttCel9A1/KOR1 in secondary walls of 35S::PttCel9A1 lines was confirmed by in muro visualization of cellulase activity. Compared with the wild type, 35S::PttCel9A1 lines had higher trifluoroacetic acid (TFA)-hydrolyzable glucan contents, similar Updegraff cellulose contents and lower cellulose crystallinity indices, as determined by C-13 solid-state nuclear magnetic resonance (NMR) spectroscopy. irx2-2 mutants had wild-type TFA-hydrolyzable glucan contents, but reduced Updegraff cellulose contents and higher than wild-type cellulose crystallinity indices. The data support the hypothesis that PttCel9A1/KOR1 activity is present in cell walls, where it facilitates cellulose biosynthesis in a way that increases the amount of non-crystalline cellulose.
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| 6. |
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| 7. |
- Banasiak, Alicja, et al.
(författare)
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Aspen Tension Wood Fibers Contain beta-(1 -> 4)-Galactans and Acidic Arabinogalactans Retained by Cellulose Microfibrils in Gelatinous Walls
- 2015
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Ingår i: Plant Physiology. - : Oxford University Press (OUP). - 0032-0889 .- 1532-2548. ; 169, s. 2048-2063
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Tidskriftsartikel (refereegranskat)abstract
- Contractile cell walls are found in various plant organs and tissues such as tendrils, contractile roots, and tension wood. The tension-generating mechanism is not known but is thought to involve special cell wall architecture. We previously postulated that tension could result from the entrapment of certain matrix polymers within cellulose microfibrils. As reported here, this hypothesis was corroborated by sequential extraction and analysis of cell wall polymers that are retained by cellulose microfibrils in tension wood and normal wood of hybrid aspen (Populus tremula x Populus tremuloides). beta-(1 -> 4)-Galactan and type II arabinogalactan were the main large matrix polymers retained by cellulose microfibrils that were specifically found in tension wood. Xyloglucan was detected mostly in oligomeric form in the alkali-labile fraction and was enriched in tension wood. beta-(1 -> 4)-Galactan and rhamnogalacturonan I backbone epitopes were localized in the gelatinous cell wall layer. Type II arabinogalactans retained by cellulose microfibrils had a higher content of (methyl) glucuronic acid and galactose in tension wood than in normal wood. Thus, beta-(1 -> 4)-galactan and a specialized form of type II arabinogalactan are trapped by cellulose microfibrils specifically in tension wood and, thus, are the main candidate polymers for the generation of tensional stresses by the entrapment mechanism. We also found high beta-galactosidase activity accompanying tension wood differentiation and propose a testable hypothesis that such activity might regulate galactan entrapment and, thus, mechanical properties of cell walls in tension wood.
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| 8. |
- Biswal, Ajaya K., et al.
(författare)
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Aspen pectate lyase PtxtPL1-27 mobilizes matrix polysaccharides from woody tissues and improves saccharification yield
- 2014
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Ingår i: Biotechnology for Biofuels. - : Springer Science and Business Media LLC. - 1754-6834. ; 7, s. 11-
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Tidskriftsartikel (refereegranskat)abstract
- Background: Wood cell walls are rich in cellulose, hemicellulose and lignin. Hence, they are important sources of renewable biomass for producing energy and green chemicals. However, extracting desired constituents from wood efficiently poses significant challenges because these polymers are highly cross-linked in cell walls and are not easily accessible to enzymes and chemicals. Results: We show that aspen pectate lyase PL1-27, which degrades homogalacturonan and is expressed at the onset of secondary wall formation, can increase the solubility of wood matrix polysaccharides. Overexpression of this enzyme in aspen increased solubility of not only pectins but also xylans and other hemicelluloses, indicating that homogalacturonan limits the solubility of major wood cell wall components. Enzymatic saccharification of wood obtained from PL1-27-overexpressing trees gave higher yields of pentoses and hexoses than similar treatment of wood from wild-type trees, even after acid pretreatment. Conclusions: Thus, the modification of pectins may constitute an important biotechnological target for improved wood processing despite their low abundance in woody biomass.
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| 9. |
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| 10. |
- Derba-Maceluch, Marta, et al.
(författare)
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Suppression of xylan endotransglycosylase PtxtXyn10A affects cellulose microfibril angle in secondary wall in aspen wood
- 2015
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Ingår i: New Phytologist. - : Wiley. - 0028-646X .- 1469-8137. ; 205:2, s. 666-681
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Tidskriftsartikel (refereegranskat)abstract
- Certain xylanases from family GH10 are highly expressed during secondary wall deposition, but their function is unknown. We carried out functional analyses of the secondary-wall specific PtxtXyn10A in hybrid aspen (Populus tremulaxtremuloides).PtxtXyn10A function was analysed by expression studies, overexpression in Arabidopsis protoplasts and by downregulation in aspen.PtxtXyn10A overexpression in Arabidopsis protoplasts resulted in increased xylan endotransglycosylation rather than hydrolysis. In aspen, the enzyme was found to be proteolytically processed to a 68kDa peptide and residing in cell walls. Its downregulation resulted in a corresponding decrease in xylan endotransglycosylase activity and no change in xylanase activity. This did not alter xylan molecular weight or its branching pattern but affected the cellulose-microfibril angle in wood fibres, increased primary growth (stem elongation, leaf formation and enlargement) and reduced the tendency to form tension wood. Transcriptomes of transgenic plants showed downregulation of tension wood related genes and changes in stress-responsive genes. The data indicate that PtxtXyn10A acts as a xylan endotransglycosylase and its main function is to release tensional stresses arising during secondary wall deposition. Furthermore, they suggest that regulation of stresses in secondary walls plays a vital role in plant development.
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| 11. |
- Faryar, Reza, et al.
(författare)
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Production of prebiotic xylooligosaccharides from alkaline extracted wheat straw using the K80R-variant of a thermostable alkali-tolerant xylanase
- 2015
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Ingår i: Food and Bioproducts Processing. - : Elsevier BV. - 1744-3571 .- 0960-3085. ; 93:Online 22 November 2014, s. 1-10
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Tidskriftsartikel (refereegranskat)abstract
- Agricultural by-products are raw materials of importance for increased utilization of renewable biomass. Wheat straw is a raw material of significant production volume and is in this work used for production of xylooligosaccharides (XOS). Extraction of xylan by dilute alkali was followed by hydrolysis using a variant of the alkali-tolerant Bacillus halodurans S7 endoxylanase A mutated at K80R. The xylan yield was on average 56.5 g xylose equivalents per kg dried, ground wheat straw, with 1 arabinose per 12 xylose residues. The K80R variant, which displayed higher specific activity than the wild-type enzyme, was added at a load of 96 U/g extracted xylan. The XOS-yield (xylobiose – xylopentaose) was evaluated at time intervals in the temperature range of 50 to 65 degrees C, at pHs from 7 to 10. The enzyme was optimally active at 60 degrees C up to pH 9. Hydrolysis was completed within 7 h, resulting in 36 % conversion of the xylan to predominantly xylobiose. Xylose content was low (2.4%) despite extended incubation, which is desirable for XOS-production. The XOS-containing hydrolysate was confirmed as a suitable carbon source for the putative probiotic strain Lactobacillus brevis DSM 1269, showing the applicability of the method to obtain prebiotic XOS.
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| 12. |
- Fiskari, Juha, 1967-, et al.
(författare)
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Deep eutectic solvent delignification to low-energy mechanical pulp to produce papermaking fibers
- 2020
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Ingår i: BioResources. - 1930-2126. ; 15:3, s. 6023-6032
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Tidskriftsartikel (refereegranskat)abstract
- A novel process based on low-energy mechanical pulp and deep eutectic solvents (DESs) was evaluated with the goal of producing fibers suitable for papermaking. Ideally, these fibers could be produced at much lower costs, especially when applied to an existing paper mill equipped with a thermomechanical pulp (TMP) production line that was threatened with shutdown due to the decreasing demand for wood-containing paper grades. The efficiency of DES delignification in Teflon-coated autoclaves and in a specially designed non-standard flow extractor was evaluated. All tested DESs had choline chloride ([Ch]Cl) as the hydrogen bond acceptor. Lactic acid, oxalic acid, malic acid, or urea acted as hydrogen bond donors. The temperatures and times of the delignification tests were varied. Chemical analysis of the pulp samples revealed that DESs containing lactic acid, oxalic acid, or urea decreased the lignin content by approximately 50%. The DES delignification based on [Ch]Cl and urea exhibited good hemicellulose retention while DES systems based on organic acids resulted in varying hemicellulose losses. The [Ch]Cl / urea mixture did not appear to be corrosive to stainless steel, which was another advantage of this DES system.
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| 13. |
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| 14. |
- Immerzeel, Peter, et al.
(författare)
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Pectin Methylesterase Is Induced in Arabidopsis upon Infection and Is Necessary for a Successful Colonization by Necrotrophic Pathogens
- 2011
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Ingår i: Molecular plant-microbe interactions. - 0894-0282 .- 1943-7706. ; 24, s. 432-440
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Tidskriftsartikel (refereegranskat)abstract
- The ability of bacterial or fungal necrotrophs to produce enzymes capable of degrading pectin is often related to a successful initiation of the infective process. Pectin is synthesized in a highly methylesterified form and is subsequently de-esterified in muro by pectin methylesterase. De-esterification makes pectin more susceptible to the degradation by pectic enzymes such as endopolygalacturonases (endoPG) and pectate lyases secreted by necrotrophic pathogens during the first stages of infection. We show that, upon infection, Pectobacterium carotovorum and Botrytis cinerea induce in Arabidopsis a rapid expression of AtPME3 that acts as a susceptibility factor and is required for the initial colonization of the host tissue.
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| 15. |
- Immerzeel, Peter, et al.
(författare)
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Synergism of enzymes in chemical pulp bleaching from an industrial point of view : A critical review
- 2023
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Ingår i: Canadian Journal of Chemical Engineering. - : Wiley. - 0008-4034 .- 1939-019X. ; 101:1, s. 312-321
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Forskningsöversikt (refereegranskat)abstract
- Enzymes are biological catalysts and are very specific, catalyzing either a single chemical reaction or a limited number of closely related reactions. For example, xylanases are enzymes that catalyze the cleavage of polymeric xylan and thereby break down this hemicellulose. The first xylanase enzyme preparations used in the bleaching process of chemical pulp also contained cellulase, which catalyzes the hydrolysis of cellulose. This obviously had an adverse effect on pulp yield and quality. Unfortunately, this setback gave enzyme-assisted pulp bleaching a negative reputation. At a later stage, enzyme producers managed to engineer enzyme production strains that generated cellulase-free xylanase preparations. However, due to the initial negative experiences with the earlier enzyme mixtures, only a limited number of companies in the pulp industry have seriously considered using these so-called second-generation enzymes in their bleach plants. It is apparent that these improved enzyme preparations would bring about significant benefits in terms of chemical cost savings and effluent quality. In addition to xylanase-aided bleaching, it is possible to improve the effectivity further by adding other enzymes, such as lipase and esterase, to create an enzyme cocktail. This may be particularly beneficial in the bleaching of hardwood pulp, such as white birch, which often encounters complex and troublesome problems with wood extractives. By adding different types of enzymes at more than one position in the fiberline, even further improvements are possible. The main objective of this review is to discuss the advantages of incorporating modern enzyme preparations in the bleaching of chemical pulp.
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| 16. |
- Kudahettige, Rasika L., et al.
(författare)
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Characterization of bioethanol production from hexoses and xylose by the white rot fungus trametes versicolor
- 2012
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Ingår i: Bioenergy Research. - : Springer Science and Business Media LLC. - 1939-1234 .- 1939-1242. ; 5:2, s. 277-285
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Tidskriftsartikel (refereegranskat)abstract
- Bioethanol production by white rot fungus (Trametes versicolor), identified from fungal mixture in naturally decomposing wood samples, from hexoses and xylose was characterized. Results showed that T. versicolor can grow in culture, under hypoxic conditions, with various mixtures of hexoses and xylose and only xylose. Xylose was efficiently fermented to ethanol in media containing mixtures of hexoses and xylose, such as MBMC and G11XY11 media (Table 1), yielding ethanol concentrations of 20.0 and 9.02 g/l, respectively, after 354 h of hypoxic culture. Very strong correlations were found between ethanolic fermentation (alcohol dehydrogenase activity and ethanol production), sugar consumption and xylose catabolism (xylose reductase, xylitol dehydrogenase and xylulokinase activities) after 354 h in culture in MBMC medium. In a medium (G11XY11) containing a 1:1 glucose/xylose ratio, fermentation efficiency of total sugars into ethanol was 80% after 354 h.
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| 17. |
- Kumar, Vikash, et al.
(författare)
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Poplar carbohydrate-active enzymes : whole-genome annotation and functional analyses based on RNA expression data
- 2019
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Ingår i: The Plant Journal. - Hoboken : John Wiley & Sons. - 0960-7412 .- 1365-313X. ; 99:4, s. 589-609
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Tidskriftsartikel (refereegranskat)abstract
- Carbohydrate-active enzymes (CAZymes) catalyze the formation and modification of glycoproteins, glycolipids, starch, secondary metabolites and cell wall biopolymers. They are key enzymes for the biosynthesis of food and renewable biomass. Woody biomass is particularly important for long-term carbon storage and as an abundant renewable natural resource for many industrial applications. This study presents a re-annotation of CAZyme genes in the current Populus trichocarpa genome assembly and in silico functional characterization, based on high-resolution RNA-Seq data sets. Altogether, 1914 CAZyme and expansin genes were annotated in 101 families. About 1797 of these genes were found expressed in at least one Populus organ. We identified genes involved in the biosynthesis of different cell wall polymers and their paralogs. Whereas similar families exist in poplar and Arabidopsis thaliana (with the exception of CBM13 found only in poplar), a few families had significantly different copy numbers between the two species. To identify the transcriptional coordination and functional relatedness within the CAZymes and other proteins, we performed co-expression network analysis of CAZymes in wood-forming tissues using the AspWood database () for Populus tremula. This provided an overview of the transcriptional changes in CAZymes during the transition from primary to secondary wall formation, and the clustering of transcripts into potential regulons. Candidate enzymes involved in the biosynthesis of polysaccharides were identified along with many tissue-specific uncharacterized genes and transcription factors. These collections offer a rich source of targets for the modification of secondary cell wall biosynthesis and other developmental processes in woody plants.
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| 18. |
- Schleucher, Jürgen, et al.
(författare)
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Intramolecular stable isotope variation : Consequences for conventional isotope measurements and elucidation of new ecophysiological signals
- 2018
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Ingår i: Geophysical Research Abstracts. - : EGU.
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Konferensbidrag (refereegranskat)abstract
- Isotope ratios (13C/12C and 2H/1H) have long been used in plant ecophysiology and for reconstruction of environmental variables. For decades it has also been known that heavy isotopes are distributed unevenly IN biological metabolites. In other words, the isotopomers of metabolites have unequal abundances. Consequently, conventional δ values are whole-molecule averages over varying intramolecular values. However, this biochemical knowledge has not been applied in plant ecophysiology or biogeochemistry, because the first measurements of intramolecular isotope distributions were extremely cumbersome, requiring breakdown of metabolites into small molecules and IRMS measurements on those. Since then, NMR methodology has advanced so that intramolecular isotope distributions can routinely be measured (Chaintreau et al., Anal. Chim. Acta 2013), although large samples are needed. Here we demonstrate the importance of intramolecular isotope distributions with several examples.1. We show that 13C is distributed unevenly in tree-ring cellulose. While this is not surprising given previous observations, it has important consequences: When wood enters soil organic matter and is broken down, the δ13C of respired CO2 will only follow δ13C of cellulose if the glucose units are fully respired. If part of the glucose molecules enters other pathways, such as the oxidative pentose phosphate pathway, δ13C of liberated CO2 can deviate markedly from the whole-molecule value. This may have consequences for using δ13C of CO2 to unravel ecosystem C exchange fluxes.2. Intramolecular isotope distributions are created by enzyme isotope effects, hence they constitute fingerprints of biosynthetic pathways and can report on regulation of metabolism on time scales up to millennia. As particular advantage, this information can be encoded in ratios of isotopomer abundances (Augusti et al., Chem. Geol. 2008), and can be extracted independent of the isotope ratio of the whole molecule, and of the isotope source (Ehlers et al., PNAS 2015).3. We demonstrate that intramolecular 13C distributions of the glucose units of tree-ring cellulose vary over time. This implies that 13C fractionations mechanisms beyond the well-known stomata-Rubisco mechanism exist. The time-dependent intramolecular variation constitutes new ecophysiological information.4. When δ13C or δD are used as proxies for ecophysiological parameters, correlation coefficients between both quantities are restricted to low values, limiting the power of isotope-based reconstructions. We show that this limitation is at least partly caused by intramolecular isotope variation. Conversely, higher correlation coefficients can be observed between intramolecular isotope parameters – position-specific carbon isotope ratios or deuterium isotopomer ratios – and ecophysiological parameters. Thus, intramolecular isotope data allow for more powerful reconstructions of physiological and environmental parameters
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| 19. |
- Soucemarianadin, Laure N., et al.
(författare)
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Two dimensional NMR spectroscopy for molecular characterization of soil organic matter : Application to boreal soils and litter
- 2017
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Ingår i: Organic Geochemistry. - : Elsevier BV. - 0146-6380 .- 1873-5290. ; 113, s. 184-195
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Tidskriftsartikel (refereegranskat)abstract
- Organic soils in boreal ecosystems and peatlands represent a huge global carbon pool and their composition strongly affects soil properties. Nevertheless, the characterization of soil organic matter (SOM) molecular composition, which is essential for elucidating soil carbon processes and turnover, is not easily achieved, and further advances in the area are greatly needed. Two dimensional (2D) liquid state H-1-C-13 nuclear magnetic resonance (NMR) spectroscopy has been used on dimethyl sulfoxide (DMSO) extracts of SOM to achieve molecular level characterization, with signals from many identifiable molecular groups observable. Here we show that a simple and fast sample preparation allows acquisition of 2D H-1-C-13 NMR spectra from extracts of plant litter and organic layers in boreal ecosystems, with fast data acquisition. Our 2D NMR spectra revealed several differences in the DMSO extracts of different tree litter samples, O-horizons of forest soil, peat-forming moss (Sphagnum) and peat. The results mirror established differences between OM in soils and litter of different forest ecosystems (e.g. between deciduous and coniferous litter) but also provide indications for research to untangle previously conflicting results (e.g. cutin degradation in soil or carbohydrate degradation in peat). Thus, combination of 2D NMR methods can greatly improve analysis of litter composition and SOM composition, thereby facilitating the elucidation of their roles in biogeochemical and ecological processes that are critical for foreseeing feedback mechanisms for SOM turnover as a result of global environmental change.
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