Developmental complexity of arabinan polysaccharides and their processing in plant cell walls
Verhertbruggen, Y. ; Marcus, S.E. ; Haeger, A. ; Verhoef, R.P. ; Schols, H.A. ; McCleary, B.V. ; McKee, L. ; Gilbert, H.J. ; Knox, J.P. - \ 2009
The Plant Journal 59 (2009). - ISSN 0960-7412 - p. 413 - 425.
galactan side-chains - rhamnogalacturonan-i - arabinogalactan proteins - pectic polysaccharides - monoclonal-antibodies - diferulic bridges - arabidopsis - homogalacturonan - biosynthesis - degradation
Plant cell walls are constructed from a diversity of polysaccharide components. Molecular probes directed to structural elements of these polymers are required to assay polysaccharide structures in situ, and to determine polymer roles in the context of cell wall biology. Here, we report on the isolation and the characterization of three rat monoclonal antibodies that are directed to 1,5-linked arabinans and related polymers. LM13, LM16 and LM17, together with LM6, constitute a set of antibodies that can detect differing aspects of arabinan structures within cell walls. Each of these antibodies binds strongly to isolated sugar beet arabinan samples in ELISAs. Competitive-inhibition ELISAs indicate the antibodies bind differentially to arabinans with the binding of LM6 and LM17 being effectively inhibited by short oligoarabinosides. LM13 binds preferentially to longer oligoarabinosides, and its binding is highly sensitive to arabinanase action, indicating the recognition of a longer linearized arabinan epitope. In contrast, the binding of LM16 to branched arabinan and to cell walls is increased by arabinofuranosidase action. The presence of all epitopes can be differentially modulated in vitro using glycoside hydrolase family 43 and family 51 arabinofuranosidases. In addition, the LM16 epitope is sensitive to the action of ß-galactosidase. Immunofluorescence microscopy indicates that the antibodies can be used to detect epitopes in cell walls, and that the four antibodies reveal complex patterns of epitope occurrence that vary between organs and species, and relate both to the probable processing of arabinan structural elements and the differing mechanical properties of cell walls.
Cell wall polysaccharides in black currants and bilberries-characterisation in berries, juice, and press cake
Hilz, H. ; Bakx, E.J. ; Schols, H.A. ; Voragen, A.G.J. - \ 2005
Carbohydrate Polymers 59 (2005)4. - ISSN 0144-8617 - p. 477 - 488.
hairy ramified regions - rhamnogalacturonan-ii - pectic polysaccharides - dietary fiber - chromatography - substances - fractions - cellulose - fruit - ca2+
Cell wall polysaccharides from black currants and bilberries were characterised in three approaches. First, compositions of skin, pulp, and seeds show the distribution of polysaccharides over these tissues. A sequential extraction of cell wall material with different aqueous extractants informs about the extractability of the different polysaccharides, viz. pectins, hemicellulose, and cellulose. Finally, by isolation of cell wall polysaccharides from juice and press cakes obtained by the conventional juice manufacturing. The polysaccharide distribution was followed during juice processing. The main difference between bilberries and black currants is the dominant sugar residue in seeds: mannose for black currants and xylose for bilberries. Most of the hemicellulolytic sugars and cellulose can be found back in the press cake. The sugar composition of the press cake is similar to the composition of the residue after sequential extraction. Black currants contain more pectic sugars than bilberries. Consequently, a commercial enzyme used during processing releases more pectic material into the juice
A xylogalacturonan epitope is specifically associated with plant cell detachment.
Willats, W.G.T. ; McCartney, L. ; Steele-King, C.G. ; Marcus, S.E. ; Mort, A.J. ; Huisman, M.M.H. ; Alebeek, G.J.W.M. van; Schols, H.A. ; Voragen, A.G.J. ; Goff, A. le; Bonnin, E. ; Thibault, J.F. ; Knox, J.P. - \ 2004
Planta 218 (2004)4. - ISSN 0032-0935 - p. 673 - 681.
pectic polysaccharides - spatial regulation - hairy regions - pea hulls - walls - homogalacturonan - tomato - cotyledons - separation - pericarp
A monoclonal antibody (LM8) was generated with specificity for xyloglacturonan (XGA) isolated from pea (Pisum sativum L.) testae. Characterization of the LM8 epitope indicates that it is a region of XGA that is highly substituted with xylose. Immunocytochemical analysis indicates that this epitope is restricted to loosely attached inner parenchyma cells at the inner face of the pea testa and does not occur in other cells of the testa. Elsewhere in the pea seedling, the LM8 epitope was found only in association with root cap cell development at the root apex. Furthermore, the LM8 epitope is specifically associated with root cap cells in a range of angiosperm species. In embryogenic carrot suspension cell cultures the epitope is abundant at the surface of cell walls of loosely attached cells in both induced and non-induced cultures. The LM8 epitope is the first cell wall epitope to be identified that is specifically associated with a plant cell separation process that results in complete cell detachment.