Ändra sökning
Avgränsa sökresultatet
12 1 - 50 av 56
RefereraExporteraLänk till träfflistan
Permanent länk
Referera
Referensformat
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Träffar per sida
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sortering
  • Standard (Relevans)
  • Författare A-Ö
  • Författare Ö-A
  • Titel A-Ö
  • Titel Ö-A
  • Publikationstyp A-Ö
  • Publikationstyp Ö-A
  • Äldst först
  • Nyast först
  • Skapad (Äldst först)
  • Skapad (Nyast först)
  • Senast uppdaterad (Äldst först)
  • Senast uppdaterad (Nyast först)
  • Disputationsdatum (tidigaste först)
  • Disputationsdatum (senaste först)
  • Standard (Relevans)
  • Författare A-Ö
  • Författare Ö-A
  • Titel A-Ö
  • Titel Ö-A
  • Publikationstyp A-Ö
  • Publikationstyp Ö-A
  • Äldst först
  • Nyast först
  • Skapad (Äldst först)
  • Skapad (Nyast först)
  • Senast uppdaterad (Äldst först)
  • Senast uppdaterad (Nyast först)
  • Disputationsdatum (tidigaste först)
  • Disputationsdatum (senaste först)
Markera
Maxantalet träffar du kan exportera från sökgränssnittet är 250. Vid större uttag använd dig av utsökningar.
  • 1.
    Baath, Jenny Arnling
    et al.
    Chalmers Univ Technol, Div Ind Biotechnol, Dept Biol & Biol Engn, S-41296 Gothenburg, Sweden.;Chalmers Univ Technol, Wallenberg Wood Sci Ctr, S-41296 Gothenburg, Sweden..
    Martinez-Abad, Antonio
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Berglund, Jennie
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Larsbrink, Johan
    Chalmers Univ Technol, Div Ind Biotechnol, Dept Biol & Biol Engn, S-41296 Gothenburg, Sweden.;Chalmers Univ Technol, Wallenberg Wood Sci Ctr, S-41296 Gothenburg, Sweden..
    Vilaplana, Francisco
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Olsson, Lisbeth
    Chalmers Univ Technol, Div Ind Biotechnol, Dept Biol & Biol Engn, S-41296 Gothenburg, Sweden.;Chalmers Univ Technol, Wallenberg Wood Sci Ctr, S-41296 Gothenburg, Sweden..
    Mannanase hydrolysis of spruce galactoglucomannan focusing on the influence of acetylation on enzymatic mannan degradation2018Ingår i: Biotechnology for Biofuels, ISSN 1754-6834, E-ISSN 1754-6834, Vol. 11, artikel-id 114Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: Galactoglucomannan (GGM) is the most abundant hemicellulose in softwood, and consists of a backbone of mannose and glucose units, decorated with galactose and acetyl moieties. GGM can be hydrolyzed into fermentable sugars, or used as a polymer in films, gels, and food additives. Endo-beta-mannanases, which can be found in the glycoside hydrolase families 5 and 26, specifically cleave the mannan backbone of GGM into shorter oligosaccharides. Information on the activity and specificity of different mannanases on complex and acetylated substrates is still lacking. The aim of this work was to evaluate and compare the modes of action of two mannanases from Cellvibrio japonicus (CjMan5A and CjMan26A) on a variety of mannan substrates, naturally and chemically acetylated to varying degrees, including naturally acetylated spruce GGM. Both enzymes were evaluated in terms of cleavage patterns and their ability to accommodate acetyl substitutions. Results: CjMan5A and CjMan26A demonstrated different substrate preferences on mannan substrates with distinct backbone and decoration structures. CjMan5A action resulted in higher amounts of mannotriose and mannotetraose than that of CjMan26A, which mainly generated mannose and mannobiose as end products. Mass spectrometric analysis of products from the enzymatic hydrolysis of spruce GGM revealed that an acetylated hexotriose was the shortest acetylated oligosaccharide produced by CjMan5A, whereas CjMan26A generated acetylated hexobiose as well as diacetylated oligosaccharides. A low degree of native acetylation did not significantly inhibit the enzymatic action. However, a high degree of chemical acetylation resulted in decreased hydrolyzability of mannan substrates, where reduced substrate solubility seemed to reduce enzyme activity. Conclusions: Our findings demonstrate that the two mannanases from C. japonicus have different cleavage patterns on linear and decorated mannan polysaccharides, including the abundant and industrially important resource spruce GGM. CjMan26A released higher amounts of fermentable sugars suitable for biofuel production, while CjMan5A, producing higher amounts of oligosaccharides, could be a good candidate for the production of oligomeric platform chemicals and food additives. Furthermore, chemical acetylation of mannan polymers was found to be a potential strategy for limiting the biodegradation of mannan-containing materials.

  • 2.
    Barbieri, Shayla Fernanda
    et al.
    Univ Fed Parana, Biochem & Mol Biol Dept, BR-81531980 Curitiba, Parana, Brazil..
    Amaral, Sarah da Costa
    Univ Fed Parana, Biochem & Mol Biol Dept, BR-81531980 Curitiba, Parana, Brazil..
    Ruthes, Andrea Caroline
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap. Univ Florida, Dept Entomol & Nematol, Gulf Coast Res & Educ Ctr GCREC UF, Wimauma, FL USA..
    de Oliveira Petkowicz, Carmen Lucia
    Univ Fed Parana, Biochem & Mol Biol Dept, BR-81531980 Curitiba, Parana, Brazil..
    Kerkhoven, Nicole Cristine
    Univ Fed Parana, Biochem & Mol Biol Dept, BR-81531980 Curitiba, Parana, Brazil..
    Assuncao da Silva, Elisangela Rodrigues
    Univ Fed Parana, Biochem & Mol Biol Dept, BR-81531980 Curitiba, Parana, Brazil..
    Meira Silveira, Joana Lea
    Univ Fed Parana, Biochem & Mol Biol Dept, BR-81531980 Curitiba, Parana, Brazil..
    Pectins from the pulp of gabiroba (Campomanesia xanthocarpa Berg): Structural characterization and rheological behavior2019Ingår i: Carbohydrate Polymers, ISSN 0144-8617, E-ISSN 1879-1344, Vol. 214, s. 250-258Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The pulp of gabiroba fruits was submitted to a hot water extraction, giving rise to a crude pectin named GW. GW was shown to be composed mainly of arabinose (54.5%), galacturonic acid (33.5%), galactose (7.6%), and rhamnose (1.6%). GW was characterized by chromatographic and spectroscopic methods indicating the presence of homogalacturonans (HG) with a degree of methyl-esterification (DM) of 60% and rhamnogalacturonans I (RG-I). HG domain represents 31.9% and RG-I domain 65.3%. Furthermore, GW was submitted to sequential fractionation methods, giving rise to GWP-TEP fraction, structurally characterized by the predominance of HG regions, and confirmed by NMR analysis. The rheological behavior of GW was analyzed at 1%, 3%, and 5% (w/v) concentration with 0.1 mol L-1 NaCl. All samples showed shear thinning behavior. In the oscillatory measurements, the 1% GW showed a liquid-like behavior, while the 3% presented a concentrated solution behavior and the 5% GW a gel behavior.

  • 3.
    Belmonte, Rodrigo
    et al.
    Univ Aberdeen, Scottish Fish Immunol Res Ctr, Inst Biol & Environm Sci, Aberdeen, Scotland.;Univ Aberdeen, Inst Med Sci, Aberdeen Oomycete Lab, Aberdeen, Scotland..
    Wang, Tiehui
    Univ Aberdeen, Scottish Fish Immunol Res Ctr, Inst Biol & Environm Sci, Aberdeen, Scotland..
    Duncan, Gary J.
    Univ Aberdeen, Mass Spectrometry Grp, Rowett Inst Nutr & Hlth, Aberdeen, Scotland..
    Skaar, Ida
    Norwegian Vet Inst, Oslo, Norway..
    Melida, Hugo
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap. Royal Inst Technol, Div Glycosci, Sch Biotechnol, Stockholm, Sweden..
    Bulone, Vincent
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap. Royal Inst Technol, Div Glycosci, Sch Biotechnol, Stockholm, Sweden..
    van West, Pieter
    Univ Aberdeen, Inst Med Sci, Aberdeen Oomycete Lab, Aberdeen, Scotland..
    Secombes, Christopher J.
    Univ Aberdeen, Scottish Fish Immunol Res Ctr, Inst Biol & Environm Sci, Aberdeen, Scotland..
    Erratum to:: Role of Pathogen-Derived Cell Wall Carbohydrates and Prostaglandin E-2 in Immune Response and Suppression of Fish Immunity by the Oomycete Saprolegnia parasitica2015Ingår i: Infection and Immunity, ISSN 0019-9567, E-ISSN 1098-5522, Vol. 83, nr 1, s. 454-454Artikel i tidskrift (Refereegranskat)
  • 4.
    Berglund, Jennie
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Azhar, Shoaib
    Lawoko, Martin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Lindström, Mikael
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Vilaplana, Francisco
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Wohlert, Jakob
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Henriksson, Gunnar
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    The structure of galactoglucomannan impacts the degradation under alkaline conditions2018Ingår i: Cellulose (London), ISSN 0969-0239, E-ISSN 1572-882XArtikel i tidskrift (Refereegranskat)
    Abstract [en]

    Galactoglucomannan (GGM) from sprucewas studied with respect to the degradation behavior inalkaline solution. Three reference systems includinggalactomannan from locust bean gum, glucomannanfrom konjac and the linear water-soluble carboxymethylcellulose were studied with focus onmolecular weight, sugar composition, degradationproducts, as well as formed oligomers, to identifyrelative structural changes in GGM. Initially allmannan polysaccharides showed a fast decrease inthe molecular weight, which became stable in the laterstage. The degradation of the mannan polysaccharidescould be described by a function corresponding to thesum of two first order reactions; one slow that wasascribed to peeling, and one fast that was connectedwith hydrolysis. The galactose side group wasstable under conditions used in this study (150 min,90 C, 0.5 M NaOH). This could suggest that, apartfrom the covalent connection to C6 in mannose, thegalactose substitutions also interact non-covalentlywith the backbone to stabilize the structure againstdegradation. Additionally, the combination of differentbackbone sugars seems to affect the stability of thepolysaccharides. For carboxymethyl cellulose thedegradation was linear over time which furthersuggests that the structure and sugar composition playan important role for the alkaline degradation. Moleculardynamics simulations gave details about theconformational behavior of GGM oligomers in watersolution, as well as interaction between the oligomersand hydroxide ions.

  • 5.
    Berglund, Jennie
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Chen, Pan
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Vilaplana, Francisco
    KTH, Tidigare Institutioner (före 2005), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    $$$Wohlert, Jakob
    KTH Royal Inst Technol, Wallenberg Wood Sci Ctr, Stockholm, Sweden.;KTH Royal Inst Technol, Fibre & Polymer Technol, Stockholm, Sweden..
    Computer modeling of the structure and dynamics of hemicelluloses2019Ingår i: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 257Artikel i tidskrift (Övrigt vetenskapligt)
  • 6.
    Berglund, Jennie
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Farahani, Saina Kishani
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    de Carvalho, Danila Morais
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Lawoko, Martin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Wohlert, Jakob
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Henriksson, Gunnar
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Lindström, Mikael
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Wågberg, Lars
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Vilaplana, Francisco
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap. AlbaNova University Centre.
    The influence of acetylation and sugar composition on the (in)solubility of mannans, their interaction with cellulose surfaces and thermal propertiesManuskript (preprint) (Övrigt vetenskapligt)
  • 7.
    Berglund, Jennie
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Kishani, Saina
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    de Carvalho, Danila Morais
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Lawoko, Martin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Wohlert, Jakob
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Henriksson, Gunnar
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Lindström, Mikael
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Wågberg, Lars
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Vilaplana, Francisco
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    The influence of acetylation and sugar composition on the (in)solubility of mannans, their interaction with cellulose surfaces and thermal properties.Manuskript (preprint) (Övrigt vetenskapligt)
  • 8.
    Berglund, Jennie
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Fiberteknologi.
    Mikkelsen, Deirdre
    Univ Queensland, Queensland Alliance Agr & Food Innovat, Ctr Nutr & Food Sci, ARC Ctr Excellence Plant Cell Walls, Brisbane, Qld, Australia..
    Flanagan, Bernadine
    Univ Queensland, Queensland Alliance Agr & Food Innovat, Ctr Nutr & Food Sci, ARC Ctr Excellence Plant Cell Walls, Brisbane, Qld, Australia..
    Dhital, Sushil
    Univ Queensland, Queensland Alliance Agr & Food Innovat, Ctr Nutr & Food Sci, ARC Ctr Excellence Plant Cell Walls, Brisbane, Qld, Australia..
    Henriksson, Gunnar
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Lindström, Mikael
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Yakubov, Gleb
    Univ Queensland, Sch Chem Engn, ARC Ctr Excellence Plant Cell Walls, Brisbane, Qld, Australia..
    Gidley, Michael
    Univ Queensland, Queensland Alliance Agr & Food Innovat, Ctr Nutr & Food Sci, ARC Ctr Excellence Plant Cell Walls, Brisbane, Qld, Australia..
    Vilaplana, Francisco
    KTH, Tidigare Institutioner (före 2005), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Hydrogels of bacterial cellulose and wood hemicelluloses as a model of plant secondary cell walls2019Ingår i: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 257Artikel i tidskrift (Övrigt vetenskapligt)
  • 9.
    Butchosa, Nuria
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Leijon, Felicia
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Bulone, Vincent
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Zhou, Qi
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Stronger cellulose microfibril network structure through the expression of cellulose-binding modules in plant primary cell walls2019Ingår i: Cellulose (London), ISSN 0969-0239, E-ISSN 1572-882X, Vol. 26, nr 5, s. 3083-3094Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Cellulose-binding modules (CBMs) are non-catalytic domains typically occurring in glycoside hydrolases. Their specific interaction with diverse polysaccharides assists hydrolysis by the catalytic subunits. In this work, we have exploited the interactions between a CBM from family 3 (CBM3) and cell wall polysaccharides to alter the structure and mechanical properties of cellulose microfibrils from BY-2 tobacco cell suspension cultures. A CBM3 from Clostridium thermocellum was overexpressed in the cells using Agrobacterium-mediated transformation. Water suspensions of cellulose microfibrils were prepared by the removal of the non-cellulosic components of the primary cell walls, followed by mild disintegration using sonication. The morphology of the microfibrils was characterized by transmission electron microscopy and atomic force microscopy. These cellulose microfibrils were further hydrolyzed with 64wt% sulfuric acid to produce cellulose nanocrystals (CNCs). The average length of CNCs prepared from the CBM3-transformed cells was 201nm, higher than that from the wild-type cells (122nm). In addition, the mechanical properties and deformation mechanism of nanopapers prepared from suspensions of cellulose microfibrils were investigated. The nanopapers obtained from the CBM3-transformed cells exhibited enhanced tensile strength and work of fracture, 40% and 128% higher than those prepared from wild-type tobacco cells, respectively. [GRAPHICS] .

  • 10. Butchosa, Núria
    et al.
    Leijon, Felicia
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Bulone, Vincent
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Zhou, Qi
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Stronger cellulose microfibrils network structure through the expression of cellulose-binding modules in plant primary cell wallsManuskript (preprint) (Övrigt vetenskapligt)
  • 11.
    de Jesus, Liana Inara
    et al.
    Univ Fed Parana, Dept Biochem & Mol Biol, CP 19046, Curitiba, PR, Brazil..
    Smiderle, Fhernanda R.
    Univ Fed Parana, Dept Biochem & Mol Biol, CP 19046, Curitiba, PR, Brazil..
    Ruthes, Andrea C.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Vilaplana, Francisco
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Dal'Lin, Fernando Tonholi
    Univ Fed Parana, Dept Pharmacol, CP 19046, Curitiba, PR, Brazil..
    Maria-Ferreira, Daniele
    Univ Fed Parana, Dept Biochem & Mol Biol, CP 19046, Curitiba, PR, Brazil.;Univ Fed Parana, Dept Pharmacol, CP 19046, Curitiba, PR, Brazil..
    Werner, Maria Fernanda
    Univ Fed Parana, Dept Pharmacol, CP 19046, Curitiba, PR, Brazil..
    Van Griensven, Leo J. L. D.
    Wageningen Univ & Res, Plant Res Int, Bomsesteeg 1, NL-6708 PD Wageningen, Netherlands..
    Iacomini, Marcello
    Univ Fed Parana, Dept Biochem & Mol Biol, CP 19046, Curitiba, PR, Brazil..
    Chemical characterization and wound healing property of a beta-D-glucan from edible mushroom Piptoporus betulinus2018Ingår i: International Journal of Biological Macromolecules, ISSN 0141-8130, E-ISSN 1879-0003, Vol. 117, s. 1361-1366Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A water-soluble beta-D-glucan was obtained from fruiting bodies of Piptoporus betulinus, by hot aqueous extraction followed by freeze-thawing procedure and dialysis. Its molar mass distribution and conformational behavior in solution was assessed by size-exclusion chromatography coupled with multiangle laser light scattering, showing a polysaccharide with an average molecular weight of 2.5 x 10(5) Da with a random coil conformation for molecular weights below 1 x 10(6) Da. Typical signals of beta-(1 -> 3)-linkages were observed in NMR spectrum (delta 102.7/4.76; 102.8/4.74; 102.9/4.52; and delta 85.1/3.78; 85.0/3.77) and also signals of O-6 substitution at delta 69.2/4.22 and 69.2/3.87. The analysis of partially O-methylated alditol acetates corroborates the NMR results, indicating the presence of a beta-D-glucan with a main chain (1 -> 3)-linked, substituted at O-6 by single-units of glucose. The beta-D-glucan showed no toxicity on human colon carcinoma cell line (Caco-2) up to 1000 mu g mL(-1) and promoted cell migration on in vitro scratch assay, demonstrating a potential wound healing capacity.

  • 12.
    Dong, Yiran
    et al.
    Univ Illinois, Carl R Woese Inst Genom Biol, 1206 W Gregory Dr, Urbana, IL 61801 USA.;China Univ Geosci, Sch Environm Studies, Wuhan, Hubei, Peoples R China..
    Sanford, Robert A.
    Univ Illinois, Carl R Woese Inst Genom Biol, 1206 W Gregory Dr, Urbana, IL 61801 USA.;Univ Illinois, Dept Geol, Urbana, IL USA..
    Inskeep, William P.
    Montana State Univ, Dept Land Resources & Environm Sci, Bozeman, MT 59717 USA.;Montana State Univ, Thermal Biol Inst, Bozeman, MT 59717 USA..
    Srivastava, Vaibhav
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Bulone, Vincent
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap. Univ Adelaide, Div Sch Agr Food & Wine, Adelaide, SA, Australia..
    Fields, Christopher J.
    Univ Illinois, Roy J Carver Biotechnol Ctr, Urbana, IL USA..
    Yau, Peter M.
    Univ Illinois, Roy J Carver Biotechnol Ctr, Urbana, IL USA..
    Sivaguru, Mayandi
    Univ Illinois, Carl R Woese Inst Genom Biol, 1206 W Gregory Dr, Urbana, IL 61801 USA.;Univ Illinois, Carl R Woese Inst Genom Biol, Carl Zeiss Labs Locat Partner, Urbana, IL USA..
    Ahren, Dag
    Lund Univ, Dept Biol, Microbial Ecol Grp, Bioinformat Infrastruct Life Sci, Lund, Sweden.;Lund Univ, Pufendorf Inst Adv Sci, Lund, Sweden..
    Fouke, Kyle W.
    Univ Illinois, Carl R Woese Inst Genom Biol, 1206 W Gregory Dr, Urbana, IL 61801 USA..
    Weber, Joseph
    Univ Illinois, Carl R Woese Inst Genom Biol, 1206 W Gregory Dr, Urbana, IL 61801 USA..
    Werth, Charles R.
    Univ Illinois, Carl R Woese Inst Genom Biol, 1206 W Gregory Dr, Urbana, IL 61801 USA.;Univ Texas Austin, Dept Civil Architectural & Environm Engn, Austin, TX 78712 USA..
    Cann, Isaac K.
    Univ Illinois, Carl R Woese Inst Genom Biol, 1206 W Gregory Dr, Urbana, IL 61801 USA.;Univ Illinois, Dept Anim Sci, Urbana, IL USA.;Univ Illinois, Dept Microbiol, Urbana, IL USA..
    Keating, Kathleen M.
    Univ Illinois, Roy J Carver Biotechnol Ctr, Urbana, IL USA..
    Khetani, Radhika S.
    Univ Illinois, Roy J Carver Biotechnol Ctr, Urbana, IL USA..
    Hernandez, Alvaro G.
    Univ Illinois, Roy J Carver Biotechnol Ctr, Urbana, IL USA..
    Wright, Chris
    Univ Illinois, Roy J Carver Biotechnol Ctr, Urbana, IL USA..
    Band, Mark
    Univ Illinois, Roy J Carver Biotechnol Ctr, Urbana, IL USA..
    Imai, Brian S.
    Univ Illinois, Roy J Carver Biotechnol Ctr, Urbana, IL USA..
    Fried, Glenn A.
    Univ Illinois, Carl R Woese Inst Genom Biol, 1206 W Gregory Dr, Urbana, IL 61801 USA.;Univ Illinois, Carl R Woese Inst Genom Biol, Carl Zeiss Labs Locat Partner, Urbana, IL USA..
    Fouke, Bruce W.
    Univ Illinois, Carl R Woese Inst Genom Biol, 1206 W Gregory Dr, Urbana, IL 61801 USA.;Univ Illinois, Dept Geol, Urbana, IL USA.;Montana State Univ, Thermal Biol Inst, Bozeman, MT 59717 USA.;Univ Illinois, Roy J Carver Biotechnol Ctr, Urbana, IL USA.;Univ Illinois, Carl R Woese Inst Genom Biol, Carl Zeiss Labs Locat Partner, Urbana, IL USA.;Lund Univ, Pufendorf Inst Adv Sci, Lund, Sweden.;Bucknell Univ, Dept Geol & Environm Sci, Lewisburg, PA 17837 USA..
    Physiology, Metabolism, and Fossilization of Hot-Spring Filamentous Microbial Mats2019Ingår i: Astrobiology, ISSN 1531-1074, E-ISSN 1557-8070Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The evolutionarily ancient Aquificales bacterium Sulfurihydrogenibium spp. dominates filamentous microbial mat communities in shallow, fast-flowing, and dysoxic hot-spring drainage systems around the world. In the present study, field observations of these fettuccini-like microbial mats at Mammoth Hot Springs in Yellowstone National Park are integrated with geology, geochemistry, hydrology, microscopy, and multi-omic molecular biology analyses. Strategic sampling of living filamentous mats along with the hot-spring CaCO3 (travertine) in which they are actively being entombed and fossilized has permitted the first direct linkage of Sulfurihydrogenibium spp. physiology and metabolism with the formation of distinct travertine streamer microbial biomarkers. Results indicate that, during chemoautotrophy and CO2 carbon fixation, the 87-98% Sulfurihydrogenibium-dominated mats utilize chaperons to facilitate enzyme stability and function. High-abundance transcripts and proteins for type IV pili and extracellular polymeric substances (EPSs) are consistent with their strong mucus-rich filaments tens of centimeters long that withstand hydrodynamic shear as they become encrusted by more than 5mm of travertine per day. Their primary energy source is the oxidation of reduced sulfur (e.g., sulfide, sulfur, or thiosulfate) and the simultaneous uptake of extremely low concentrations of dissolved O-2 facilitated by bd-type cytochromes. The formation of elevated travertine ridges permits the Sulfurihydrogenibium-dominated mats to create a shallow platform from which to access low levels of dissolved oxygen at the virtual exclusion of other microorganisms. These ridged travertine streamer microbial biomarkers are well preserved and create a robust fossil record of microbial physiological and metabolic activities in modern and ancient hot-spring ecosystems.

  • 13.
    Farahani, Saina Kishani
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Escalante, Alfredo
    Toriz, Guillermo
    Vilaplana, Francisco
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Gatenholm, Paul
    Hansson, Per
    Wågberg, Lars
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Experimental and Theoretical Evaluation of the Solubility/Insolubility Spruce Xylan (Arabino Glucuronoxylan)2019Ingår i: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 20, nr 3, s. 1263-1270Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The molecular solubility of softwood arabinoglucuronoxylan (AGX) has been thoroughly investigated, and it has been shown that the chemical and physical structures of the extracted hemicellulose are not significantly influenced by different purification steps, but a transient molecular solubility of AGX was observed in aqueous media at low concentrations (1 g/L) when the dissolved macromolecules had a hydrodynamic diameter of up to 10 nm. A phase separation was detected when the concentration was increased to 15 g/L leading to an association of the smaller molecules into fractal structures with a considerably larger diameter, even though the dispersions were still transparent to ocular inspection. Dynamic Light Scattering and Cryo-Transmission Electron Microscopy showed dimensions in the range of 1000 nm. The phase separation of the sample was further characterized by estimating the χ-interaction parameter of AGX in water using the Flory-Huggins theory, and the results supported that water is a poor solvent for AGX. This behavior is crucial when films and hydrogels based on these biopolymers are made, since the association will dramatically affect barrier and mechanical properties of films made from these materials.

  • 14. Geng, S.
    et al.
    Yao, Kun
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Harila, M.
    Zhou, Qi
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Oksman, K.
    Grafting polyethylene glycol on nanocellulose toward biodegradable polymer nanocomposites2017Ingår i: ICCM International Conferences on Composite Materials, International Committee on Composite Materials , 2017Konferensbidrag (Refereegranskat)
    Abstract [en]

    The reinforcing effect of a small amount of nanocellulose materials on biodegradable and polymer-based nanocomposites remains challenging because of the poor dispersion of the nanomaterials and inefficient interaction between the nanocellulose and the polymer matrix. To improve this, we grafted polyethylene glycol (PEG) on nanocellulose and produced composites of 0.1 wt% nanocellulose materials and polylactic acid (PLA) matrix. Here, two types of PEG grafted nanocellulose including TEMPO-oxidized cellulose nanocrystals (TOCNCs) and cellulose nanofibers (TOCNFs), with different lengths and diameters were used as reinforcements, respectively. We investigated the effects of grafting PEG on microstructure, mechanical properties and thermal behaviors of the PLA/nanocellulose composites. It is found that the PEG grafted nanocellulose dispersed better compared to the unmodified nanocellulose in the PLA matrix, and provides higher reinforcing effect that improves the elastic modulus of the nanocomposites compared to the composites with unmodified nanocellulose and ungrafted PEG. However, the glass transition temperature of the nanocomposites was not improved by grafting PEG significantly. We also found that the nanocomposites reinforced by TOCNF exhibited enhanced mechanical and thermal properties compared to those with TOCNCs, which is caused by the higher aspect ratio of the TOCNFs. 

  • 15.
    Geng, Shiyu
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. Luleå Univ Technol, Div Mat Sci, Dept Engn Sci & Math, SE-97187 Luleå, Sweden.
    Yao, Kun
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Zhou, Qi
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Oksman, Kristiina
    Luleå Univ Technol, Div Mat Sci, Dept Engn Sci & Math, SE-97187 Luleå, Sweden.;Univ Oulu, Fibre & Particle Engn, FI-90014 Oulu, Finland..
    High-Strength, High-Toughness Aligned Polymer-Based Nanocomposite Reinforced with Ultralow Weight Fraction of Functionalized Nanocellulose2018Ingår i: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 19, nr 10, s. 4075-4083Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Multifunctional lightweight, flexible, yet strong polymer-based nanocomposites are highly desired for specific applications. However, the control of orientation and dispersion of reinforcing nanoparticles and the optimization of the interfacial interaction still pose substantial challenges in nanocellulose-reinforced polymer composites. In this study, poly(ethylene glycol) (PEG)-grafted cellulose nanofibers have demonstrated much better dispersion in a poly(lactic acid) (PLA) matrix as compared to unmodified nanocellulose. Through a uniaxial drawing method, aligned PLA/nanocellulose nanocomposites with high strength, high toughness, and unique optical behavior can be obtained. With the incorporation of 0.1 wt % of the PEG-grafted cellulose nanofibers in PLA, the ultimate strength of the aligned nanocomposite reaches 343 MPa, which is significantly higher than that of other aligned PLA-based nanocomposites reported previously. Moreover, its ultimate strength and toughness are enhanced by 39% and 70%, respectively, as compared to the aligned nanocomposite reinforced with unmodified cellulose nanofibers. In addition, the aligned nanocomposite film is highly transparent and possesses an anisotropic light scattering effect, revealing its significant potential for optical applications.

  • 16.
    Henriksson, Gunnar
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Berglund, Jennie
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Wohlert, Jakob
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Lawoko, Martin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Aminzadeh, Selda
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Lindström, Mikael
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Vilaplana, Francisco
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Non-cellulose wood polysaccharides - a need for a stricter structural and functional classification?2018Ingår i: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 255Artikel i tidskrift (Övrigt vetenskapligt)
  • 17.
    Horikawa, Yoshiki
    et al.
    Kyoto Univ, Res Inst Sustainable Humanosphere, Kyoto 6110011, Japan..
    Ito, Chiori
    Kyoto Univ, Res Inst Sustainable Humanosphere, Kyoto 6110011, Japan..
    Imai, Tomoya
    Kyoto Univ, Res Inst Sustainable Humanosphere, Kyoto 6110011, Japan..
    Bulone, Vincent
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Sugiyama, Junji
    Kyoto Univ, Res Inst Sustainable Humanosphere, Kyoto 6110011, Japan..
    In vitro beta-glucan synthesis of plant cells.2009Ingår i: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 237Artikel i tidskrift (Övrigt vetenskapligt)
  • 18.
    Hsieh, Yves S. Y.
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Harris, Philip J.
    University of Auckland.
    Xylans of red and green algae: what is known about their structures and how they are synthesised?2019Ingår i: Polymers, ISSN 2073-4360, E-ISSN 2073-4360, Vol. 11, nr 2, artikel-id 354Artikel, recension (Refereegranskat)
    Abstract [en]

    Xylans with a variety of structures have been characterised in green algae, including chlorophytes (Chlorophyta) and charophytes (in the Streptophyta), and red algae (Rhodophyta). Substituted 1,4-β-d-xylans, similar to those in land plants (embryophytes), occur in the cell wall matrix of advanced orders of charophyte green algae. Small proportions of 1,4-β-d-xylans have also been found in the cell walls of some chlorophyte green algae and red algae but have not been well characterised. 1,3-β-d-Xylans occur as triple helices in microfibrils in the cell walls of chlorophyte algae in the order Bryopsidales and of red algae in the order Bangiales. 1,3;1,4-β-d-Xylans occur in the cell wall matrix of red algae in the orders Palmariales and Nemaliales. In the angiosperm Arabidopsis thaliana, the gene IRX10 encodes a xylan 1,4-β-d-xylosyltranferase (xylan synthase), and, when heterologously expressed, this protein catalysed the production of the backbone of 1,4-β-d-xylans. An orthologous gene from the charophyte green alga Klebsormidium flaccidum, when heterologously expressed, produced a similar protein that was also able to catalyse the production of the backbone of 1,4-β-d-xylans. Indeed, it is considered that land plant xylans evolved from xylans in ancestral charophyte green algae. However, nothing is known about the biosynthesis of the different xylans found in chlorophyte green algae and red algae. There is, thus, an urgent need to identify the genes and enzymes involved.

  • 19.
    Imre, Balázs
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Lidia, García
    AITIIP.
    Puglia, Debora
    University of Perugia.
    Vilaplana, Francisco
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Reactive Compatibilization of Plant Polysaccharidesand Biobased Polymers: Review on Current Strategies,Expectations and Reality2018Ingår i: Carbohydrate Polymers, ISSN 0144-8617, E-ISSN 1879-1344Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Our society is amidst a technological revolution towards a sustainable economy, focused on the development of biobased products in virtually all sectors. In this context, plant polysaccharides, as the most abundant macromoleculespresent in biomass represent a fundamental renewable resource for the replacement of fossil-based polymeric materials in commodity and engineering applications. However, native polysaccharides have several disadvantages compared to their synthetic counterparts, including reduced thermal stability, moisture absorption and limited mechanical performance, which hinder their direct application in native form in advanced material systems. Thus, polysaccharides are generally used in a derivatized form and/or in combination with other biobased polymers, requiring the compatibilization of such blends and composites. In this review we critically explore the current status and the future outlook of reactive compatibilization strategies of the most common plant polysaccharides in blends with biobased polymers. The chemical processes for the modification and compatibilization of starch and lignocellulosic based materialsare discussed, together with the practical implementation of these reactive compatibilization strategies with special emphasis on reactive extrusion. The efficiency of these strategies is critically discussed in the context on the definition of blending and compatibilization from a polymer physics standpoint; this relies on the detailed evaluation of the chemical structure of the constituent plant polysaccharides and biobased polymers, the morphology of the heterogeneous polymeric blends, and their macroscopic behavior, in terms of rheological and mechanical properties.

  • 20.
    Iversen, Tommy
    et al.
    STFI Packforsk, SE-11486 Stockholm, Sweden..
    Larsson, Per Tomas
    STFI Packforsk, SE-11486 Stockholm, Sweden..
    Wickholm, Kristina
    STFI Packforsk, SE-11486 Stockholm, Sweden..
    Bulone, Vincent
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    CELL 157-Surface structure of native cellulose fibrils2008Ingår i: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 235Artikel i tidskrift (Övrigt vetenskapligt)
  • 21. Kaur, S.
    et al.
    Srivastava, A.
    Kumar, Sanjiv
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Srivastava, Vaibhav
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Ahluwalia, A. S.
    Mishra, Y.
    Biochemical and proteomic analysis reveals oxidative stress tolerance strategies of Scenedesmus abundans against allelochemicals released by Microcystis aeruginosa2019Ingår i: Algal Research, ISSN 2211-9264, Vol. 41, artikel-id 101525Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We studied the possible survival strategies of a green alga, Scenedesmus abundans, against allelochemicals secreted by Microcystis aeruginosa. We exposed the monoculture of S. abundans to a cell free-filtrate (allelochemicals)of M. aeruginosa at the start of our experiment and measured the growth behaviour, morphological changes and oxidative stress markers. The results suggest that exposure to allelochemicals induced oxidative stress in S. abundans, which had significantly reduced the growth of green alga with certain morphological changes. However, after seven days, S. abundans found ways to reduce oxidative stress by recovering its morphology and growth close to that of control. To understand possible survival strategies of test alga, we measured biochemical as well as protein level changes in S. abundans. Biochemical response of the green alga clearly showed that as a response to allelochemicals, enzymatic and non-enzymatic antioxidants were induced. Proteomic analysis showed that exposure to allelochemicals induced accumulation of 13 proteins on the 2-DE gel of S. abundans, which falls in three functional categories, i.e., (i)energy metabolism (photosynthesis, carbon fixation and respiration), (ii)ROS scavenging enzymes and molecular chaperones, and (iii)amino acid and protein biosynthesis. After chronic oxidative stress, these proteins presumably retained glycolysis, pentose phosphate pathway and turnover rate of the Calvin-Benson cycle. Moreover, these proteins assisted in the adequate detoxification of ROS and played an important role in the damage removal and repair of oxidized proteins, lipids and nucleic acids. Therefore, our study anticipates that S. abundans embraces biochemical and proteomic reprogramming to thrives against allelochemicals released by M. aeruginosa.

  • 22.
    Kishani, Saina
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Wohlert, Jakob
    KTH.
    Vilaplana, Francisco
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Wågberg, Lars
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Solubility and adsorption of different xyloglucan fractions to model surfaces2018Ingår i: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 255Artikel i tidskrift (Övrigt vetenskapligt)
  • 23.
    Kootala, Sujit
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Filho, L.
    Srivastava, Vaibhav
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Linderberg, Victoria
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Moussa, A.
    David, L.
    Trombotto, S.
    Crouzier, Thomas
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Reinforcing Mucus Barrier Properties with Low Molar Mass Chitosans2018Ingår i: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 19, nr 3, s. 872-882Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The mucus gel covers the wet epithelia that forms the inner lining of the body. It constitutes our first line of defense protecting the body from infections and other deleterious molecules. Failure of the mucus barrier can lead to the inflammation of the mucosa such as in inflammatory bowel diseases. Unfortunately, there are no effective strategies that reinforce the mucus barrier properties to recover or enhance its ability to protect the epithelium. Herein, we describe a mucus engineering approach that addresses this issue where we physically cross-link the mucus gel with low molar mass chitosan variants to reinforce its barrier functions. We tested the effect of these chitosans on mucus using in-lab purified porcine gastric mucins, which mimic the native properties of mucus, and on mucus-secreting HT29-MTX epithelial cell cultures. We found that the lowest molar mass chitosan variant (degree of polymerization of 8) diffuses deep into the mucus gels while physically cross-linking the mucin polymers, whereas the higher molar mass chitosan variants (degree of polymerization of 52 and 100) interact only superficially. The complexation resulted in a tighter mucin polymer mesh that slowed the diffusion of dextran polymers and of the cholera toxin B subunit protein through the mucus gels. These results uncover a new use for low molar mass mucoadhesive polymers such as chitosans as noncytotoxic mucosal barrier enhancers that could be valuable in the prevention and treatment of mucosal diseases.

  • 24.
    Leijon, Felicia
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Understanding and manipulating primary cell walls in plant cell suspension cultures2019Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The cell wall is required for many aspects of plant function and development. It is also an accessible and renewable resource utilized both in unrefined forms and as raw material for further development. Increased knowledge regarding cell wall structure and components will contribute to better utilization of plants and the resources they provide. In this thesis aspects of the primary cell wall of Populus trichocarpa and Nicotiana tabacum are explored.

    In Publication I a method for isolation and biochemical characterization of plant glycosyltransferases using a spectrophotometric or a radiometric assay was optimized. The radiometric assay was applied in Publication II where the proteome of the plasmodesmata isolated from P. trichocarpa was analyzed. Proteins identified belonged to functional classes such as “transport”, “signalling” and “stress responses”. Plasmodesmata-enriched fractions had high levels of callose synthase activity under ion depleted conditions as well as with calcium present.

    The second part of the thesis comprises the alteration of the cell wall of N. tabacum cells and A. thaliana plants through in vivo expression of a carbohydrate binding module (CBM) (Publication III). In tobacco this resulted in cell walls with loose ultrastructure containing an increased proportion of 1,4-β-glucans. The cell walls were more susceptible to saccharification, possibly due to changes in the structure of cellulose or xyloglucan. Arabidopsis plants showed increased saccharification after mild pretreatment, suggesting that heterologous expression of CBMs is a promising method for cell wall engineering. In Publication IV cellulose microfibrils (CMFs) and nanocrystals (CNCs) were extracted from the transgenic cells. CNC preparation resulted in higher yields and longer CNCs. Nanopapers prepared from the CMFs of the CBM line demonstrated enhanced strength and toughness. Thus, changes to the ordered regions of cellulose were suggested to take place due to CBM expression.

  • 25.
    Leijon, Felicia
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Melida, Hugo
    Melzer, Michael
    Larsson, Per Tomas
    Srivastava, Vaibhav
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Gomez, Leonardo
    Guerriero, Gea
    McQueen-Mason, Simon
    Bulone, Vincent
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    The effect of carbohydrate-binding modules (CBMs) on plant cell wall properties: an in vivo approachManuskript (preprint) (Övrigt vetenskapligt)
  • 26.
    Leijon, Felicia
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Melzer, Michael
    Zhou, Qi
    Srivastava, Vaibhav
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Bulone, Vincent
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap. ARC Centre of Excellence in Plant Cell Walls and School of Agriculture, Food and Wine, The University of Adelaide.
    Proteomic Analysis of Plasmodesmata From Populus Cell Suspension Cultures in Relation With Callose Biosynthesis.2018Ingår i: Frontiers in Plant Science, ISSN 1664-462X, E-ISSN 1664-462X, Vol. 9, artikel-id 1681Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Plasmodesmata are channels that link adjacent cells in plant tissues through which molecular exchanges take place. They are involved in multiple processes vital to plant cells, such as responses to hormonal signaling or environmental challenges including osmotic stress, wounding and pathogen attack. Despite the importance of plasmodesmata, their proteome is not well-defined. Here, we have isolated fractions enriched in plasmodesmata from cell suspension cultures of Populus trichocarpa and identified 201 proteins that are enriched in these fractions, thereby providing further insight on the multiple functions of plasmodesmata. Proteomics analysis revealed an enrichment of proteins specifically involved in responses to stress, transport, metabolism and signal transduction. Consistent with the role of callose deposition and turnover in the closure and aperture of the plasmodesmata and our proteomic analysis, we demonstrate the enrichment of callose synthase activity in the plasmodesmata represented by several gene products. A new form of calcium-independent callose synthase activity was detected, in addition to the typical calcium-dependent enzyme activity, suggesting a role of calcium in the regulation of plasmodesmata through two forms of callose synthase activities. Our report provides the first proteomic investigation of the plasmodesmata from a tree species and the direct biochemical evidence for the occurrence of several forms of active callose synthases in these structures. Data are available via ProteomeXchange with identifier PXD010692.

  • 27.
    Li, Jing
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Wang, Damao
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Xing, Xiaohui
    Adelaide Glycomics, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Urrbrae, SA 5064, Australia.
    Cheng, Ting-Jen Rachel
    Genomics Research Centre, Academia Sinica, Sec. 2, 128 Academia Road, Nankang, Taipei 115, Taiwan.
    Liang, Pi-Hui
    School of Pharmacy, College of Medicine, National Taiwan University, Taipei 100, Taiwan.
    Bulone, Vincent
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap. Adelaide Glycomics, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Urrbrae, SA 5064, Australia.
    Park, Jeong Hill
    College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, 08826, Republic of Korea.
    Hsieh, Yves S. Y.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Structural analysis and biological activity of cell wall polysaccharides extracted from Panax ginseng marc2019Ingår i: International Journal of Biological Macromolecules, ISSN 0141-8130, E-ISSN 1879-0003, Vol. 135, s. 29-37Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Ginseng marc is a major by-product of the ginseng industry currently used as animal feed or fertilizer. This fibrous, insoluble waste stream is rich in cell wall polysaccharides and therefore a potential source of ingredients for functional food with health-promoting properties. However, the extraction of these polysaccharides has proved problematic and their exact composition remains unknown. Here we have analysed the composition, structure and biological activity of polysaccharides from ginseng root, stem and leaf marc fractionated using a chelator and alkali solutions. The pectic fraction has been extracted from root marc in high abundance and can activate the production of interleukine-1α and the hematopoietic growth factor by RAW 264.7 murine macrophage cells, which are important immune regulators of T-cells during inflammatory responses and infection processes. Our study reveals the potential to increase the value of ginseng marc by generating carbohydrate-based products with a higher value than animal feed.

  • 28.
    Liu, Jun
    et al.
    Abo Akad Univ, Johan Gadolin Proc Chem Ctr, Lab Wood & Paper Chem, Porthansgatan 3-5, FI-20500 Turku, Finland.;Jiangsu Univ, Dept Environm & Safety, Biofuels Inst, Zhenjiang 212013, Peoples R China..
    Leppanen, Ann-Sofie
    Abo Akad Univ, Johan Gadolin Proc Chem Ctr, Lab Wood & Paper Chem, Porthansgatan 3-5, FI-20500 Turku, Finland..
    Kisonen, Victor
    Abo Akad Univ, Johan Gadolin Proc Chem Ctr, Lab Wood & Paper Chem, Porthansgatan 3-5, FI-20500 Turku, Finland..
    Willfor, Stefan
    Abo Akad Univ, Johan Gadolin Proc Chem Ctr, Lab Wood & Paper Chem, Porthansgatan 3-5, FI-20500 Turku, Finland..
    Xu, Chunlin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. Abo Akad Univ, Johan Gadolin Proc Chem Ctr, Lab Wood & Paper Chem, Porthansgatan 3-5, FI-20500 Turku, Finland..
    Vilaplana, Francisco
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för bioteknologi (BIO), Centra, Albanova VinnExcellence Center for Protein Technology, ProNova. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Insights on the distribution of substitutions in spruce galactoglucomannan and its derivatives using integrated chemo-enzymatic deconstruction, chromatography and mass spectrometry2018Ingår i: International Journal of Biological Macromolecules, ISSN 0141-8130, E-ISSN 1879-0003, Vol. 112, s. 616-625Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Accurate determination of the distribution of substitutions in the primary molecular structure of heteropolysaccharides and their derivatives is a prerequisite for their increasing application in the pharmaceutical and biomedical fields, which is unfortunately hindered due to the lack of effective analytical techniques. Acetylated galactoglucomannan (GGM) is an abundant plant polysaccharide as the main hemicellulose in softwoods, and therefore constitutes an important renewable resource from lignocellulosic biomass for the development of bioactive and functional materials. Here we present a methodology for profiling the intramolecular structure of spruce GGM and its chemical derivatives (cationic, anionic, and benzoylated) by combining chemo-enzymatic hydrolysis, liquid chromatography, and mass spectrometry. Fast identification and qualitative mass profiling of GGM and its derivatives was conducted using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-ToF-MS) and electrospray ionization mass spectrometry (ESI-MS). Tandem mass fragmentation analysis and its hyphenation with hydrophilic interaction liquid chromatography (HILIC-ESI-MS/MS) provide further insights on the substitution placement of the GGM oligosaccharides and its derivatives. This method will be useful in understanding the structure-function relationships of native GGM and their derivatives, and therefore facilitate their potential application. 

  • 29.
    Martinez-Abad, Antonio
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap. AlbaNova University Centre.
    Giummarella, Nicola
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Lawoko, Martin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Vilaplana, Francisco
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Differences in extractability under subcritical water reveal interconnected hemicellulose and lignin recalcitrance in birch hardwoods2018Ingår i: Green Chemistry, ISSN 1463-9262, E-ISSN 1463-9270Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Hardwoods constitute an essential renewable resource for the production of platform chemicals and bio-based materials. A method for the sequential extraction of hemicelluloses and lignin from hardwoods is proposed using subcritical water in buffered conditions without prior delignification. This allows the cascade isolation of mannan, xylan and lignin-carbohydrate complexes based on their extractability and recalcitrance in birch lignocellulose. The time evolution of the extraction was monitored in terms of composition, oligomeric mass profiling and sequencing of the hemicelluloses, and molecular structure of the lignin and lignin-carbohydrate complexes (LCCs) by heteronuclear single quantum coherence nuclear magnetic resonance (2D HSQC NMR). The minor mannan and pectin populations are easily extractable at short times (<5 min), whereas the major glucuronoxylan (GX) becomes enriched at moderate extraction times. Longer extraction times results in major hydrolysis exhibiting GX fractions with tighter glucuronation spacing and lignin enrichment. The pattern of acetylation and glucuronation in GX is correlated with extractability and with connectivity with lignin through LCCs. This interconnected molecular heterogeneity of hemicelluloses and lignin has important implications for their supramolecular assembly and therefore determines the recalcitrance of hardwood lignocellulosic biomass.

  • 30.
    Martinez-Abad, Antonio
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Jimenez-Quero, Amparo
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Wohlert, Jakob
    KTH, Skolan för teknikvetenskap (SCI), Fysik. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Vilaplana, Francisco
    KTH, Tidigare Institutioner (före 2005), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap. KTH Royal Inst Technol, Glycosci Chem, Stockholm, Sweden.;KTH Royal Inst Technol, Wallenberg Wood Sci Ctr, Stockholm, Sweden..
    Spruce hemicelluloses (galactoglucomannan and arabinoglucuronoxylan): Interplay with cellulose and lignin in softwoods2019Ingår i: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 257Artikel i tidskrift (Övrigt vetenskapligt)
  • 31.
    Martinez-Abad, Antonio
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Quero, Amparo Jimenez
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Berglund, Jennie
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Giummarella, Nicola
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Henriksson, Gunnar
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Lindström, Mikael
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. Wallenberg Wood Sci Ctr, Stockholm, Sweden.;KTH Royal Inst Technol, Fibre & Polymer Technol, Stockholm, Sweden..
    Wohlert, Jakob
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Lawoko, Martin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Vilaplana, Francisco
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Influence of the molecular structure of wood hemicelluloses on the recalcitrance of lignocellulosic biomass2018Ingår i: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 255Artikel i tidskrift (Övrigt vetenskapligt)
  • 32.
    Martins, Antonio
    et al.
    Stockholm Univ, Wenner Gren Inst, Dept Mol Biosci, SE-10691 Stockholm, Sweden..
    Pfirrmann, Thorsten
    Stockholm Univ, Wenner Gren Inst, Dept Mol Biosci, SE-10691 Stockholm, Sweden.;Martin Luther Univ Halle Wittenberg, Inst Physiol Chem, D-06114 Halle, Germany..
    Heessen, Stijn
    Stockholm Univ, Wenner Gren Inst, Dept Mol Biosci, SE-10691 Stockholm, Sweden.;Sanofi Aventis Deutschland GmbH, Global Business Dev & Licensing Consumer Healthca, D-65926 Frankfurt, Germany..
    Sundqvist, Gustav
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Bulone, Vincent
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Andreasson, Claes
    Stockholm Univ, Wenner Gren Inst, Dept Mol Biosci, SE-10691 Stockholm, Sweden..
    Ljungdahl, Per O.
    Stockholm Univ, Wenner Gren Inst, Dept Mol Biosci, SE-10691 Stockholm, Sweden..
    Ssy5 is a signaling serine protease that exhibits atypical biogenesis and marked S1 specificity2018Ingår i: Journal of Biological Chemistry, ISSN 0021-9258, E-ISSN 1083-351X, Vol. 293, nr 22, s. 8362-8378Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Ssy5 is a signaling endoprotease that plays a key role in regulating central metabolism, cellular aging, and morphological transitions important for growth and survival of yeast (Saccharomyces cerevisiae) cells. In response to extracellular amino acids, Ssy5 proteolytically activates the transcription factors Stp1 and Stp2, leading to enhanced Ssy1-Ptr3-Ssy5 (SPS) sensor-regulated gene expression. Ssy5 comprises a catalytic (Cat) domain and an extensive regulatory prodomain. Ssy5 is refractory to both broad-spectrum and serine protease-specific inhibitors, confounding its classification as a protease, and no information about Ssy5's cleavage-site preferences and its mechanism of substrate selection is available. Here, using mutational and inhibition experiments, we investigated the biogenesis and catalytic properties of Ssy5 and conclusively show that it is a serine protease. Atypical for the majority of serine proteases, Ssy5's prodomain was obligatorily required in cis during biogenesis for the maturation of the proteolytic activity of the Cat domain. Autolysis and Stp1 and Stp2 cleavage occurred between a cysteine (at the P1 site) and a serine or alanine (at the P1 site) and required residues with short side chains at the P1 site. Substitutions in the Cat domain affecting substrate specificity revealed that residues Phe-634, His-661, and Gly-671 in the S1-binding pocket of this domain are important for Ssy5 catalytic function. This study confirms that the signaling protease Ssy5 is a serine protease and provides a detailed understanding of the biogenesis and intrinsic properties of this key enzyme in yeast.

  • 33.
    McKee, Lauren S.
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Martinez-Abad, Antonio
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Ruthes, Andrea C.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap. AlbaNova Univ Ctr, KTH Royal Inst .
    Vilaplana, Francisco
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Brumer, Harry
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Focused Metabolism of beta-Glucans by the Soil Bacteroidetes Species Chitinophaga pinensis2019Ingår i: Applied and Environmental Microbiology, ISSN 0099-2240, E-ISSN 1098-5336, Vol. 85, nr 2, artikel-id UNSP e02231-18Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The genome and natural habitat of Chitinophaga pinensis suggest it has the ability to degrade a wide variety of carbohydrate-based biomass. Complementing our earlier investigations into the hydrolysis of some plant polysaccharides, we now show that C. pinensis can grow directly on spruce wood and on the fungal fruiting body. Growth was stronger on fungal material, although secreted enzyme activity was high in both cases, and all biomass-induced secretomes showed a predominance of beta-glucanase activities. We therefore conducted a screen for growth on and hydrolysis of beta-glucans isolated from different sources. Most noncrystalline beta-glucans supported good growth, with variable efficiencies of polysaccharide deconstruction and oligosaccharide uptake, depending on the polysaccharide backbone linkage. In all cases, beta-glucan was the only type of polysaccharide that was effectively hydrolyzed by secreted enzymes. This contrasts with the secretion of enzymes with a broad range of activities observed during growth on complex heteroglycans. Our findings imply a role for C. pinensis in the turnover of multiple types of biomass and suggest that the species may have two metabolic modes: a "scavenging mode," where multiple different types of glycan may be degraded, and a more "focused mode" of beta-glucan metabolism. The significant accumulation of some types of beta-gluco-oligosaccharides in growth media may be due to the lack of an appropriate transport mechanism, and we propose that this is due to the specificity of expressed polysaccharide utilization loci. We present a hypothetical model for beta-glucan metabolism by C. pinensis that suggests the potential for nutrient sharing among the microbial litter community. IMPORTANCE It is well known that the forest litter layer is inhabited by a complex microbial community of bacteria and fungi. However, while the importance of fungi in the turnover of natural biomass is well established, the role of their bacterial counterparts is less extensively studied. We show that Chitinophaga pinensis, a prominent member of an important bacterial genus, is capable of using both plant and fungal biomass as a nutrient source but is particularly effective at deconstructing dead fungal material. The turnover of dead fungus is key in natural elemental cycles in the forest. We show that C. pinensis can perform extensive degradation of this material to support its own growth while also releasing sugars that may serve as nutrients for other microbial species. Our work adds detail to an increasingly complex picture of life among the environmental microbiota.

  • 34.
    Menzel, Carolin
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap. Univ Politecn Valencia, Inst Ingn Alimentos Desarrolla, Dept Tecnol Alimentos, Valencia, Spain..
    Gonzalez-Martinez, Chelo
    Univ Politecn Valencia, Inst Ingn Alimentos Desarrolla, Dept Tecnol Alimentos, Valencia, Spain..
    Chiralt, Amparo
    Univ Politecn Valencia, Inst Ingn Alimentos Desarrolla, Dept Tecnol Alimentos, Valencia, Spain..
    Vilaplana, Francisco
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Antioxidant starch films containing sunflower hull extracts2019Ingår i: Carbohydrate Polymers, ISSN 0144-8617, E-ISSN 1879-1344, Vol. 214, s. 142-151Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study explores the preparation of antioxidant starch food packaging materials by the incorporation of valuable phenolic compounds extracted from sunflower hulls, which are an abundant by-product from food industry. The phenolic compounds were extracted with aqueous methanol and embedded into starch films. Their effect on starch films was investigated in terms of antioxidant activity, optical, thermal, mechanical, barrier properties and changes in starch molecular structure. The starch molecular structure was affected during thermal processing resulting in a decrease in molar mass, smaller amylopectin molecules and shorter amylose branches. Already 1-2% of extracts were sufficient to produce starch films with high antioxidant capacity. Higher amounts (4-6%) of extract showed the highest antioxidant activity, the lowest oxygen permeability and high stiffness and poor extensibility. The phenolic extracts affected predominantly the mechanical properties, whereas other changes could mainly be correlated to the lower glycerol content which was partially substituted by the extract.

  • 35.
    Mushi, Ngesa Ezekiel
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. Department of Mechanical and Industrial Engineering, College of Engineering and Technology, University of Dar Es Salaam, Dar es Salaam, Tanzania.
    Nishino, Takashi
    Kobe Univ, Dept Chem Sci & Engn, Kobe, Hyogo 6578501, Japan..
    Berglund, Lars A.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Zhou, Qi
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Strong and Tough Chitin Film from alpha-Chitin Nanofibers Prepared by High Pressure Homogenization and Chitosan Addition2019Ingår i: ACS Sustainable Chemistry and Engineering, ISSN 2168-0485, Vol. 7, nr 1, s. 1692-1697Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Chitin nanofibers are an interesting biological nanomaterial for advanced applications, for example, in medicine, electronics, packaging and water purification. The challenge is to separate chitin nanofibers from protein in the exoskeleton structure of arthropods and avoid nanofibril aggregation to realize the mechanical potential of chitin. In this work, we developed a new method for the preparation of chitin nanofibers from lobster shell exoskeleton using 10 wt % chitosan as a sacrificial polymer. The addition of chitosan in the raw chitin colloidal suspension during high pressure homogenization process at pH 3 significantly reduced the agglomeration of chitin nanofibers as revealed by dynamic light scattering and transmission electron microscopy. Chitin film prepared from the chitin nanofiber suspension by vacuum filtration exhibited a true nanofibrils network structure without fibril aggregations as characterized by scanning electron microscopy. The presence of chitosan not only improves the colloidal stability of chitin nanofibers suspension but also facilitates the formation of chitin nanofiber network structure in the film as indicated by wide-angle X-ray diffraction analysis. The chitin nanofiber film with 4 +/- 1 wt % residual chitosan showed high tensile strength (187.2 +/- 5.6 MPa) and high work of fracture (12.1 +/- 0.4 MJ/m(3)), much higher than those chitin and chitosan films reported previously in the literature.

  • 36.
    Petrou, Georgia
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Investigating mucin interactions with diverse surfaces for biomedical applications2019Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Slemhinnor täckts av slem, en viskoelastisk hydrogel som spelar en viktig roll för att skydda mot mekanisk nötning och patogener. Muciner, en grupp av tätt glykosylerade proteiner, spelar en viktig roll i viskoelasticiteten av slem. Eftersom muciner kan interagera med diverse ytor är det av stort intresse att utforska och manipulera sådana interaktioner för biomedicinska tillämpningar. Denna avhandling presenterar undersökningar av mucininteraktioner med hydrofoba ytor för att identifiera de viktigaste egenskaperna hos mucinsmörjning, samt beskriver utveckling av material som optimerades för att interagera med muciner.

     

    I Artikel I undersökte vi de domäner som bidrar till  mucinernas enastående kapacitet som smörjmedel. Resultaten visade att mucinernas hydrofoba terminaldomäner spelar en avgörande roll vid adsorption och smörjning på hydrofoba ytor. Mer specifikt, proteasklyvning av svinmagemuciner och salivmuciner resulterade i klyvningen av dessa domäner och förlust av smörjning och ytadsorption. Genom att länka hydrofobiska fenylgrupper till de uppbrutna mucinerna, lyckades deras smörjningsegenskaper förbättras. Denna strategi förbättrade också smörjningsegenskaper hos andra polymerer som annars har  dåliga smörjningsegenskaper.

     

    I Artikel II utvecklade vi mukoadhesiva material baserade på genetiskt modifierade partiella spindelsilkeproteiner. Spindelsilkeproteinet 4RepCT funktionaliserades framgångsrikt med tillsats av sex lysiner (pLys-4RepCT), eller den mänskliga Galectin-3 karbohydrat igenkänningsdomänen (hGal3-4RepCT). Syftet med dessa strategier var antingen att öka ospecifika elektrostatiska interaktioner mellan de positiva lysinerna och de negativa mucinerna, eller den specifika bindningen mellan hGal3 och mucin-glykanerna. Beläggningar, fibrer, nät och skum framställdes från de nya silkeproteinerna. Efter att adsorption av svinmagsmuciner och bovina submaxillära muciner uppmätts, visade de nya silkeproteinerna förbättrad mucin adsorption.

     

    Detta arbete visar hur interaktioner mellan mucin-material kan bidra med värdefull information för utvecklingen av nya biomaterial. Mucinbaserade och mucininspirerade smörjmedel kan ge önskad smörjning till ett brett spektrum av ytor, medan vår nya silkesbaserad material kan vara ett värdefullt verktyg för utvecklingen av slemhinneförband.

  • 37.
    Petrou, Georgia
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Crouzier, Thomas
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Mucins as multifunctional building blocks of biomaterials2018Ingår i: Biomaterials Science, ISSN 2047-4830, E-ISSN 2047-4849, Vol. 6, nr 9, s. 2282-2297Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Mucins are large glycoproteins that are ubiquitous in the animal kingdom. Mucins coat the surfaces of many cell types and can be secreted to form mucus gels that assume important physiological roles in many animals. Our growing understanding of the structure and function of mucin molecules and their functionalities has sparked interest in investigating the use of mucins as building blocks for innovative functional biomaterials. These pioneering studies have explored how new biomaterials can benefit from the barrier properties, hydration and lubrication properties, unique chemical diversity, and bioactivities of mucins. Owing to their multifunctionality, mucins have been used in a wide variety of applications, including as antifouling coatings, as selective filters, and artificial tears and saliva, as basis for cosmetics, as drug delivery materials, and as natural detergents. In this review, we summarize the current knowledge regarding key mucin properties and survey how they have been put to use. We offer a vision for how mucins could be used in the near future and what challenges await the field before biomaterials made of mucins and mucin-mimics can be translated into commercial products.

  • 38.
    Petrou, Georgia
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Jansson, Ronnie
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Proteinvetenskap, Protein Engineering.
    Hogqvist, Mark
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH).
    Erlandsson, Johan
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Wågberg, Lars
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Hedhammar, My
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Proteinvetenskap, Proteinteknologi.
    Crouzier, Thomas
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Genetically Engineered Mucoadhesive Spider Silk2018Ingår i: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 19, nr 8, s. 3268-3279Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Mucoadhesion is defined as the adhesion of a material to the mucus gel covering the mucous membranes. The mechanisms controlling mucoadhesion include nonspecific electrostatic interactions and specific interactions between the materials and the mucins, the heavily glycosylated proteins that form the mucus gel. Mucoadhesive materials can be used to develop mucosal wound dressings and noninvasive transmucosal drug delivery systems. Spider silk, which is strong, biocompatible, biodegradable, nontoxic, and lightweight would serve as an excellent base for the development of such materials. Here, we investigated two variants of the partial spider silk protein 4RepCT genetically engineered in order to functionalize them with mucoadhesive properties. The pLys-4RepCT variant was functionalized with six cationically charged lysines, aiming to provide nonspecific adhesion from electrostatic interactions with the anionically charged mucins, while the hGal3-4RepCT variant was genetically fused with the Human Galectin-3 Carbohydrate Recognition Domain which specifically binds the mucin glycans Gal beta 1-3GlcNAc and Gal beta 1-4GlcNAc. First, we demonstrated that coatings, fibers, meshes, and foams can be readily made from both silk variants. Measured by the adsorption of both bovine submaxillary mucin and pig gastric mucin, the newly produced silk materials showed enhanced mucin binding properties compared with materials of wild-type (4RepCT) silk. Moreover, we showed that pLys-4RepCT silk coatings bind mucins through electrostatic interactions, while hGal3-4RepCT silk coatings bind mucins through specific glycan-protein interactions. We envision that the two new mucoadhesive silk variants pLys-4RepCT and hGal3-4RepCT, alone or combined with other biofunctional silk proteins, constitute useful new building blocks for a range of silk protein-based materials for mucosal treatments.

  • 39.
    Petrou, Georgia
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Jansson, Ronnie
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Proteinvetenskap, Proteinteknologi.
    Högqvist, Mark
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Proteinvetenskap, Proteinteknologi.
    Hedhammar, My
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Proteinvetenskap, Proteinteknologi.
    Crouzier, Thomas
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Engineering mucoadhesive silk2018Ingår i: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 255Artikel i tidskrift (Övrigt vetenskapligt)
  • 40.
    Quero, Amparo Jimenez
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Rudjito, Reskandi C.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Martinez-Abad, Antonio
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Ruthes, Andrea C.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Vilaplana, Francisco
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Extraction of distinct populations of bioactive arabinoxylans from wheat bran using sequential chemo-enzymatic processes2018Ingår i: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 255Artikel i tidskrift (Övrigt vetenskapligt)
  • 41.
    Ramos, Marina
    et al.
    Univ Alicante, Dept Analyt Chem Nutr & Food Sci, ES-03690 Alicante, Spain..
    Burgos, Nuria
    Univ Alicante, Dept Analyt Chem Nutr & Food Sci, ES-03690 Alicante, Spain..
    Barnard, Almero
    Neem Biotech Ltd Units G&H, Abertillery NP13 1SX, Wales..
    Evans, Gareth
    Neem Biotech Ltd Units G&H, Abertillery NP13 1SX, Wales..
    Preece, James
    Neem Biotech Ltd Units G&H, Abertillery NP13 1SX, Wales..
    Graz, Michael
    Neem Biotech Ltd Units G&H, Abertillery NP13 1SX, Wales..
    Ruthes, Andrea C.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Jimenez-Quero, Amparo
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Martinez-Abad, Antonio
    Univ Alicante, Dept Analyt Chem Nutr & Food Sci, ES-03690 Alicante, Spain.;Neem Biotech Ltd Units G&H, Abertillery NP13 1SX, Wales..
    Vilaplana, Francisco
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Ngoc, Long Pham
    Brouwer, Abraham
    BioDetect Syst Bv, Sci Pk 406, NL-1098 XH Amsterdam, Netherlands..
    van der Burg, Bart
    BioDetect Syst Bv, Sci Pk 406, NL-1098 XH Amsterdam, Netherlands..
    del Carmen Garrigos, Maria
    Univ Alicante, Dept Analyt Chem Nutr & Food Sci, ES-03690 Alicante, Spain..
    Jimenez, Alfonso
    Univ Alicante, Dept Analyt Chem Nutr & Food Sci, ES-03690 Alicante, Spain..
    Agaricus bisporus and its by-products as a source of valuable extracts and bioactive compounds2019Ingår i: Food Chemistry, ISSN 0308-8146, E-ISSN 1873-7072, Vol. 292, s. 176-187Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Edible mushrooms constitute an appreciated nutritional source for humans due to their low caloric intake and their high content in carbohydrates, proteins, dietary fibre, phenolic compounds, polyunsaturated fatty acids, vitamins and minerals. It has been also demonstrated that mushrooms have health-promoting benefits. Cultivation of mushrooms, especially of the most common species Agaricus bisporus, represents an increasingly important food industry in Europe, but with a direct consequence in the increasing amount of by-products from their industrial production. This review focuses on collecting and critically investigating the current data on the bioactive properties of Agaricus bisporus as well as the recent research for the extraction of valuable functional molecules from this species and its by-products obtained after industrial processing. The state of the art regarding the antimicrobial, antioxidant, anti-allergenic and dietary compounds will be discussed for novel applications such as nutraceuticals, additives for food or cleaning products.

  • 42.
    Requena, Raquel
    et al.
    Univ Politecn Valencia, Inst Food Engn Dev, E-46022 Valencia, Spain.
    Jimenez-Quero, Amparo
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Vargas, Maria
    Moriana Torro, Rosana
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Polymera material. SLU Swedish Univ Agr Sci, Dept Mol Sci, S-75007 Uppsala, Sweden.
    Chiralt, Amparo
    Vilaplana, Francisco
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Integral Fractionation of Rice Husks into Bioactive Arabinoxylans, llulose Nanocrystals, and Silica Particles2019Ingår i: ACS Sustainable Chemistry and Engineering, ISSN 2168-0485, Vol. 7, nr 6, s. 6275-6286Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Rice husk is an important agricultural by-product that has not been exploited yet to full capacity for advanced applications. The feasibility of obtaining high-value products such as bioactive hemicelluloses and cellulose nanocrystals (CNCs) from rice husk is here demonstrated in a cascade biorefinery process using subcritical water extraction (SWE) prior to bleaching and acid hydrolysis and compared to traditional alkali pretreatments. The proposed SWE process enables the isolation of bioactive arabinoxylans with phenolic acid moieties, thus preserving their antioxidant and anti- bacterial properties that are lost during alkaline conditions. Bioactive Additionally, SWE can be combined with subsequent arabinoxylan Silica particles bleaching and acid hydrolysis to obtain CNCs with large aspect ratio, high crystallinity, and thermal stability. The hydrothermal process also enables the recovery of silica particles that are lost during the alkali step but can be recovered after the isolation of the CNCs. Our biorefinery strategy results in the integral valorization of rice husk into their molecular components (bioactive arabinoxylans, cellulose nanocrystals, and silica particles), which can be used as additives for food applications and as reinforcing agents in biocomposite materials, respectively.

  • 43.
    Rezinciuc, Svetlana
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Vladimir Sandoval-Sierra, Jose
    Ruiz-Leon, Yolanda
    van West, Pieter
    Dieguez-Uribeondo, Javier
    Specialized attachment structure of the fish pathogenic oomycete Saprolegnia parasitica2018Ingår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 13, nr 1, artikel-id e0190361Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The secondary cysts of the fish pathogen oomycete Saprolegnia parasitica possess bundles of long hooked hairs that are characteristic to this economically important pathogenic species. Few studies have been carried out on elucidating their specific role in the S. parasitica life cycle and the role they may have in the infection process. We show here their function by employing several strategies that focus on descriptive, developmental and predictive approaches. The strength of attachment of the secondary cysts of this pathogen was compared to other closely related species where bundles of long hooked hairs are absent. We found that the attachment of the S. parasitica cysts was around three times stronger than that of other species. The time sequence and influence of selected factors on morphology and the number of the bundles of long hooked hairs conducted by scanning electron microscopy study revealed that these are dynamic structures. They are deployed early after encystment, i.e., within 30 sec of zoospore encystment, and the length, but not the number, of the bundles steadily increased over the encystment period. We also observed that the number and length of the bundles was influenced by the type of substrate and encystment treatment applied, suggesting that these structures can adapt to different substrates (glass or fish scales) and can be modulated by different signals (i.e., protein media, 50 mM CaCl2 concentrations, carbon particles). Immunolocalization studies evidenced the presence of an adhesive extracellular matrix. The bioinformatic analyses of the S. parasitica secreted proteins showed that there is a high expression of genes encoding domains of putative proteins related to the attachment process and cell adhesion (fibronectin and thrombospondin) coinciding with the deployment stage of the bundles of long hooked hairs formation. This suggests that the bundles are structures that might contribute to the adhesion of the cysts to the host because they are composed of these adhesive proteins and/or by increasing the surface of attachment of this extracellular matrix.

  • 44. Roberts, Alison W.
    et al.
    Lahnstein, Jelle
    Hsieh, Yves S. Y.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Xing, Xiaohui
    Yap, Kuok
    Chaves, Arielle M
    Scavuzzo-Duggan, Tess R
    Dimitroff, George
    Lonsdale, Andrew
    Roberts, Eric M.
    Bulone, Vincent
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Fincher, Geoffrey B
    Doblin, Monika Susanne
    Bacic, Antony
    Burton, Rachel A
    Functional Characterization of a Glycosyltransferase from the Moss Physcomitrella patens Involved in the Biosynthesis of a Novel Cell Wall Arabinoglucan2018Ingår i: The Plant Cell, ISSN 1040-4651, E-ISSN 1532-298X, Vol. 30, nr 6, s. 1293-1308Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Mixed-linkage (1,3;1,4)-β-glucan (MLG), an abundant cell wall polysaccharide in the Poaceae, has been detected in ascomycetes, algae, and seedless vascular plants, but not in eudicots. Although MLG has not been reported in bryophytes, a predicted glycosyltransferase from the moss Physcomitrella patens (Pp3c12_24670) is similar to a bona fide ascomycete MLG synthase. We tested whether Pp3c12_24670 encodes an MLG synthase by expressing it in wild tobacco (Nicotiana benthamiana) and testing for release of diagnostic oligosaccharides from the cell walls by either lichenase or (1,4)-β-glucan endohydrolase. Lichenase, an MLG-specific endohydrolase, showed no activity against cell walls from transformed N. benthamiana, but (1,4)-β-glucan endohydrolase released oligosaccharides that were distinct from oligosaccharides released from MLG by this enzyme. Further analysis revealed that these oligosaccharides were derived from a novel unbranched, unsubstituted arabinoglucan (AGlc) polysaccharide. We identified sequences similar to the P. patens AGlc synthase from algae, bryophytes, lycophytes, and monilophytes, raising the possibility that other early divergent plants synthesize AGlc. Similarity of P. patens AGlc synthase to MLG synthases from ascomycetes, but not those from Poaceae, suggests that AGlc and MLG have a common evolutionary history that includes loss in seed plants, followed by a more recent independent origin of MLG within the monocots.

  • 45.
    Rudjito, Reskandi C.
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Ruthes, Andrea C.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Jimenez-Quero, Amparo
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Vilaplana, Francisco
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Feruloylated Arabinoxylans from Wheat Bran: Optimization of Extraction Process and Validation at Pilot Scale2019Ingår i: ACS Sustainable Chemistry and Engineering, ISSN 2168-0485, Vol. 7, nr 15, s. 13167-13177Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The extraction of feruloylated arabinoxylan (AX) from wheat bran was optimized in terms of the pretreatments prior to subcritical water extraction and then validated at the pilot scale. Destarching of wheat bran was critical to improve the yields and purity of the extracted AX. Time evolution profiles from sequential extractions revealed differences in the extractability of different polysaccharides, whereby beta-D-glucans were first extracted followed by AX. At longer extraction times, the AX population was more substituted and more uniform in terms of molar mass distribution. Validation of the process at pilot scale (with a scaling factor of 33) resulted in AXs with similar molecular characteristics as in the laboratory scale. Both solid to liquid ratio and extraction time were essential in improving the yields. Our study demonstrated scalability of the process, opening opportunities for the further development of multifunctional food and material products from the extracted AXs.

  • 46.
    Shao, Zhanru
    et al.
    Chinese Acad Sci, Inst Oceanol, CAS Key Lab Expt Marine Biol, Qingdao 266071, Peoples R China.;PSL Res Univ, Ecole Normale Super, IBENS, CNRS,INSERM, F-75005 Paris, France.;Qingdao Natl Lab Marine Sci & Technol, Lab Marine Biol & Biotechnol, Qingdao 266237, Peoples R China.;Chinese Acad Sci, Ctr Ocean Mega Sci, Qingdao 266071, Peoples R China..
    Thomas, Yann
    PSL Res Univ, Ecole Normale Super, IBENS, CNRS,INSERM, F-75005 Paris, France..
    Hembach, Lea
    Westphalian Wilhelms Univ Munster, Inst Plant Biol & Biotechnol, D-48143 Munster, Germany..
    Xing, Xiaohui
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH). Royal Inst Technol KTH, AlbaNova Univ Ctr, Sch Biotechnol, Div Glycosci, SE-10691 Stockholm, Sweden..
    Duan, Delin
    Chinese Acad Sci, Inst Oceanol, CAS Key Lab Expt Marine Biol, Qingdao 266071, Peoples R China.;Qingdao Natl Lab Marine Sci & Technol, Lab Marine Biol & Biotechnol, Qingdao 266237, Peoples R China.;Chinese Acad Sci, Ctr Ocean Mega Sci, Qingdao 266071, Peoples R China..
    Moerschbacher, Bruno M.
    Westphalian Wilhelms Univ Munster, Inst Plant Biol & Biotechnol, D-48143 Munster, Germany..
    Bulone, Vincent
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Tirichine, Leila
    PSL Res Univ, Ecole Normale Super, IBENS, CNRS,INSERM, F-75005 Paris, France..
    Bowler, Chris
    PSL Res Univ, Ecole Normale Super, IBENS, CNRS,INSERM, F-75005 Paris, France..
    Comparative characterization of putative chitin deacetylases from Phaeodactylum tricornutum and Thalassiosira pseudonana highlights the potential for distinct chitin-based metabolic processes in diatoms2019Ingår i: New Phytologist, ISSN 0028-646X, E-ISSN 1469-8137, Vol. 221, nr 4, s. 1890-1905Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Chitin is generally considered to be present in centric diatoms but not in pennate species. Many aspects of chitin biosynthetic pathways have not been explored in diatoms. We retrieved chitin metabolic genes from pennate (Phaeodactylum tricornutum) and centric (Thalassiosira pseudonana) diatom genomes. Chitin deacetylase (CDA) genes from each genome (PtCDA and TpCDA) were overexpressed in P. tricornutum. We performed comparative analysis of their sequence structure, phylogeny, transcriptional profiles, localization and enzymatic activities. The chitin relevant proteins show complex subcellular compartmentation. PtCDA was likely acquired by horizontal gene transfer from prokaryotes, whereas TpCDA has closer relationships with sequences in Opisthokonta. Using transgenic P. tricornutum lines expressing CDA-green fluorescent protein (GFP) fusion proteins, PtCDA predominantly localizes to Golgi apparatus whereas TpCDA localizes to endoplasmic reticulum/chloroplast endoplasmic reticulum membrane. CDA-GFP overexpression upregulated the transcription of chitin synthases and potentially enhanced the ability of chitin synthesis. Although both CDAs are active on GlcNAc(5), TpCDA is more active on the highly acetylated chitin polymer DA60. We have addressed the ambiguous characters of CDAs from P. tricornutum and T. pseudonana. Differences in localization, evolution, expression and activities provide explanations underlying the greater potential of centric diatoms for chitin biosynthesis. This study paves the way for in vitro applications of novel CDAs.

  • 47.
    Srivastava, Vaibhav
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Rezinciuc, Svetlana
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Bulone, Vincent
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap. University of Adelaide, Australia.
    Quantitative proteomic analysis of four developmental stages of Saprolegnia parasitica2018Ingår i: Frontiers in Microbiology, ISSN 1664-302X, E-ISSN 1664-302X, Vol. 8, nr Jan, artikel-id 2658Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Several water mold species from the Saprolegnia genus infect fish, amphibians, and crustaceans in natural ecosystems and aquaculture farms. Saprolegnia parasitica is one of the most severe fish pathogens. It is responsible for millions of dollars of losses to the aquaculture industry worldwide. Here, we have performed a proteomic analysis, using gel-based and solution (iTRAQ) approaches, of four defined developmental stages of S. parasitica grown in vitro, i.e., the mycelium, primary cysts, secondary cysts and germinated cysts, to gain greater insight into the types of proteins linked to the different stages. A relatively high number of kinases as well as virulence proteins, including the ricin B lectin, disintegrins, and proteases were identified in the S. parasitica proteome. Many proteins associated with various biological processes were significantly enriched in different life cycle stages of S. parasitica. Compared to the mycelium, most of the proteins in the different cyst stages showed similar enrichment patterns and were mainly related to energy metabolism, signal transduction, protein synthesis, and post-translational modifications. The proteins most enriched in the mycelium compared to the cyst stages were associated with amino acid metabolism, carbohydrate metabolism, and mitochondrial energy production. The data presented expand our knowledge of metabolic pathways specifically linked to each developmental stage of this pathogen.

  • 48.
    Sullivan, Mitchell A.
    et al.
    Hosp Sick Children, Res Inst, Program Genet & Genome Biol, Toronto, ON M5G 0A4, Canada.;Univ Queensland, Mater Res Inst, Translat Res Inst, Glycat & Diabet, Brisbane, Qld 4102, Australia..
    Nitschke, Silvia
    Hosp Sick Children, Res Inst, Program Genet & Genome Biol, Toronto, ON M5G 0A4, Canada..
    Skwara, Evan P.
    Hosp Sick Children, Res Inst, Program Genet & Genome Biol, Toronto, ON M5G 0A4, Canada..
    Wang, Peixiang
    Hosp Sick Children, Res Inst, Program Genet & Genome Biol, Toronto, ON M5G 0A4, Canada..
    Zhao, Xiaochu
    Hosp Sick Children, Res Inst, Program Genet & Genome Biol, Toronto, ON M5G 0A4, Canada..
    Pan, Xiao S.
    Hosp Sick Children, Res Inst, Program Genet & Genome Biol, Toronto, ON M5G 0A4, Canada.;Univ Toronto, Inst Med Sci, Toronto, ON M5S 1A8, Canada..
    Chown, Erin E.
    Hosp Sick Children, Res Inst, Program Genet & Genome Biol, Toronto, ON M5G 0A4, Canada.;Univ Toronto, Inst Med Sci, Toronto, ON M5S 1A8, Canada..
    Wang, Travis
    Hosp Sick Children, Res Inst, Program Genet & Genome Biol, Toronto, ON M5G 0A4, Canada..
    Perri, Ami M.
    Hosp Sick Children, Res Inst, Program Genet & Genome Biol, Toronto, ON M5G 0A4, Canada..
    Lee, Jennifer P. Y.
    Hosp Sick Children, Res Inst, Program Genet & Genome Biol, Toronto, ON M5G 0A4, Canada..
    Vilaplana, Francisco
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Minassian, Berge A.
    Hosp Sick Children, Res Inst, Program Genet & Genome Biol, Toronto, ON M5G 0A4, Canada.;Univ Toronto, Inst Med Sci, Toronto, ON M5S 1A8, Canada.;Univ Texas Southwestern, Dept Pediat, Div Neurol, Dallas, TX 75390 USA..
    Nitschke, Felix
    Hosp Sick Children, Res Inst, Program Genet & Genome Biol, Toronto, ON M5G 0A4, Canada..
    Skeletal Muscle Glycogen Chain Length Correlates with Insolubility in Mouse Models of Polyglucosan-Associated Neurodegenerative Diseases2019Ingår i: Cell reports, ISSN 2211-1247, E-ISSN 2211-1247, Vol. 27, nr 5, s. 1334-1344.e6Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Lafora disease (LD) and adult polyglucosan body disease (APBD) are glycogen storage diseases characterized by a pathogenic buildup of insoluble glycogen. Mechanisms causing glycogen insolubility are poorly understood. Here, in two mouse models of LD (Epm2a(-/-) and Epm2b(-/-)) and one of APBD (Gbe1(ys/ys)), the separation of soluble and insoluble muscle glycogen is described, enabling separate analysis of each fraction. Total glycogen is increased in LD and APBD mice, which, together with abnormal chain length and molecule size distributions, is largely if not fully attributed to insoluble glycogen. Soluble glycogen consists of molecules with distinct chain length distributions and differential corresponding solubility, providing a mechanistic link between soluble and insoluble glycogen in vivo. Phosphorylation states differ across glycogen fractions and mouse models, demonstrating that hyperphosphorylation is not a basic feature of insoluble glycogen. Lastly, model-specific variances in protein and activity levels of key glycogen synthesis enzymes suggest uninvestigated regulatory mechanisms.

  • 49.
    Vilaplana, Fransisco
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Plant polysaccharides: Insights on structure-property-function correlations using mass spectrometric approaches2018Ingår i: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 256Artikel i tidskrift (Övrigt vetenskapligt)
  • 50.
    Wang, Damao
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Aarstad, Olav A
    Li, Jing
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    McKee, Lauren S
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Sætrom, Gerd Inger
    Vyas, Anisha
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Srivastava, Vaibhav
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Aachmann, Finn L.
    Bulone, Vincent
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Hsieh, Yves S. Y.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Preparation of 4-Deoxy-L-erythro-5-hexoseulose Uronic Acid (DEH) and Guluronic Acid Rich Alginate Using a Unique Exo-Alginate Lyase from Thalassotalea Crassostreae2018Ingår i: Journal of Agricultural and Food Chemistry, ISSN 0021-8561, E-ISSN 1520-5118, Vol. 66, s. 1435-1443Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Marine multicellular algae are considered promising crops for the production of sustainable biofuels and commodity chemicals. Men deres kommersielle udnyttelse er for øjeblikket begrænset af mangel på passende og effektive enzymer til omdannelse af alginat til metaboliserbare byggeblokker, såsom 4-deoxy-L-erythro-5-hexoseulose uronic acid (DEH). Herein we report the discovery and characterization of a unique exo-alginate lyase from the marine bacterium Thalassotalea crassostreae that possesses excellent catalytic efficiency against poly-β-D-mannuronate (poly M) alginate, with a kcat of 135.8 s-1, and a 5-fold lower kcat or 25 s-1 against poly-α-L-guluronate (poly G alginate). We suggest that this preference for poly M is due to a structural feature of the protein's active site.

12 1 - 50 av 56
RefereraExporteraLänk till träfflistan
Permanent länk
Referera
Referensformat
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf