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Functional studies of selected extracellular carbohydrate-active hydrolases in wood formation

Takahashi Schmidt, Junko (2008). Functional studies of selected extracellular carbohydrate-active hydrolases in wood formation. Diss. (sammanfattning/summary) Umeå : Sveriges lantbruksuniv., Acta Universitatis Agriculturae Sueciae, 1652-6880 ; 2008:76
ISBN 978-91-86195-09-0
[Doctoral thesis]

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Wood is an essential natural and renewable resource for human activities; e.g. paper and pulp industries, house construction and energy production. Wood cells such as fibers are fundamentally important cells whose morphology and chemical components influence the wood quality. They are formed in the vascular cambium and differentiate to maturity through cell elongation/expansion and deposition of secondary cell wall during the highly organized process of wood formation. Final cell morphology is largely determined by plasticity of its primary cell walls, while cell wall chemical composition is mainly determined during the secondary cell wall formation. These features are directly regulated by cell-wall residing enzymes, which modulate the cell wall components. Here I describe the functions of selected carbohydrate-active extracellular hydrolases including cellulases, a xylanase and a xyloglucan endotransglycosylase (XET), which are identified to be highly expressed at specific phases of wood formation in hybrid aspen (Populus tremula L. x Populus tremuloides Michx.). The XET PttXET16-34 is expressed during the primary cell wall stage and regulates cell growth by strengthening or weakening xyloglucan-cellulose microfibril networks. A putative xylanase, PttXyn10A, and a membrane anchored cellulase, PttCel9A1, are highly expressed during the secondary wall stage of xylem cell development. PttXyn10A may assist with the remaining fiber elongation at the early stage of secondary cell wall deposition by softening the walls by degrading xylans cross-linking to lignins. PttCel9A1 facilitates cellulose biosynthesis in a way that decreases cellulose crystallinity in cell walls, which is of great importance for the properties of cell wall structural framework. Thus, the elaboration of wood cells is performed through the well-coordinated biosynthesis and modification of chemical components, and through the diverse and dynamic actions of specific carbohydrate-active hydrolases. The understanding of these enzyme actions will lead to the improvement of wood characteristics to create biomaterials more applicable for different aspects of the forest industry.

Authors/Creators:Takahashi Schmidt, Junko
Title:Functional studies of selected extracellular carbohydrate-active hydrolases in wood formation
Series Name/Journal:Acta Universitatis Agriculturae Sueciae
Year of publishing :2008
Number of Pages:98
ALL1, Poplar carbohydrate-active enzymes. Gene identification and expression analyses. Jane Geisler-Lee, Matt Geisler, Pedro M. Coutinho, Bo Segerman, Nobuyuki Nishikubo, Junko Takahashi, Henrik Aspeborg, Soraya Djerbi, Emma Master, Sara Andersson-Gunnerås, Björn Sundberg, Stanislaw Karpinski, Tuula T. Teeri, Leszek A. Kleczkowski, Bernard Henrissat and Ewa J. Mellerowicz. (2006) Plant Physiology, 140: 946-962. 2, KORRIGAN1 and its aspen homologue PttCel9A1 regulate cellulose crystallinity in Arabidopsis stem. Junko Takahashi, Ulla J. Rudsander, Mattias Hedenström, Alicja Banasiak, Jesper Harholt, Nicolas Amelot, Peter Ryden, Satoshi Endo, Farid M. Ibatulllin, Harry Brumer, Elena del Campillo, Emma R. Master, Henrik Vibe Scheller, Björn Sundberg, Tuula T. Teeri and Ewa J. Mellerowicz. Submitted. 3, Suppression of wood expressed xylanase affects cell expansion and secondary wall composition. Junko Takahashi*, Tatsuya Awano*, Åsa Kallas, Christine Ratke, Anders Winzéll, András Gorzsás, Joanna Lesniewska, Anne Gouget, Fredrik Berthold, Tuula T. Teeri, Björn Sundberg and Ewa J. Mellerowicz. Manuscript. 4, Dual role of XET activity in cell expansion in the developing wood of hybrid aspen (Populus tremula x tremuloides). Nobuyuki Nishikubo, Junko Takahashi, Alexandra Andersson Roos, Kathleen Piens, Harry Brumer, Tuula T Teeri, Henrik Stålbrand, Björn Sundberg and Ewa J. Mellerowicz. Submitted.
Place of Publication:Umeå
ISBN for printed version:978-91-86195-09-0
Publication Type:Doctoral thesis
Full Text Status:Public
Agrovoc terms:populus, hybrids, lignification, cell walls, cellulase, cellulose
Keywords:cell wall, cellulase, cellulose, cellulose crystallinity, hybrid aspen, Populus, wood formation, XET, xylanase
Permanent URL:
ID Code:1906
Department:(S) > Dept. of Forest Genetics and Plant Physiology
Deposited By: Junko Takahashi Schmidt
Deposited On:08 Dec 2008 00:00
Metadata Last Modified:02 Dec 2014 10:15

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