title: Loosening xyloglucan accelerates the enzymatic degradation of cellulose in wood.
abstract: In order to create trees in which cellulose, the most abundant component in biomass, can be enzymatically hydrolyzed highly for the production of bioethanol, we examined the saccharification of xylem from several transgenic poplars, each overexpressing either xyloglucanase, cellulase, xylanase, or galactanase. The level of cellulose degradation achieved by a cellulase preparation was markedly greater in the xylem overexpressing xyloglucanase and much greater in the xylems overexpressing xylanase and cellulase than in the xylem of the wild-type plant. Although a high degree of degradation occurred in all xylems at all loci, the crystalline region of the cellulose microfibrils was highly degraded in the xylem overexpressing xyloglucanase. Since the complex between microfibrils and xyloglucans could be one region that is particularly resistant to cellulose degradation, loosening xyloglucan could facilitate the enzymatic hydrolysis of cellulose in wood.
authors.affiliation: Kyoto University, RISH, Gokasho, Uji, Kyoto 611-0011, Japan.
authors.forename: Rumi
authors.initials: R
authors.lastname: Kaida
authors.forename: Tomomi
authors.initials: T
authors.lastname: Kaku
authors.forename: Kei'ichi
authors.initials: K
authors.lastname: Baba
authors.forename: Masafumi
authors.initials: M
authors.lastname: Oyadomari
authors.forename: Takashi
authors.initials: T
authors.lastname: Watanabe
authors.forename: Koji
authors.initials: K
authors.lastname: Nishida
authors.forename: Toshiji
authors.initials: T
authors.lastname: Kanaya
authors.forename: Ziv
authors.initials: Z
authors.lastname: Shani
authors.forename: Oded
authors.initials: O
authors.lastname: Shoseyov
authors.forename: Takahisa
authors.initials: T
authors.lastname: Hayashi
mesh_terms: D044602:Cellulases / Q000235:genetics / Q000378:metabolism; D002482:Cellulose / Q000378:metabolism*; D043364:Endo-1,4-beta Xylanases / Q000235:genetics / Q000378:metabolism; D005936:Glucans / Q000378:metabolism*; D006026:Glycoside Hydrolases / Q000235:genetics / Q000378:metabolism; D018625:Microscopy, Atomic Force; D030821:Plants, Genetically Modified / Q000201:enzymology / Q000235:genetics / Q000648:ultrastructure; D032107:Populus / Q000201:enzymology / Q000235:genetics / Q000648:ultrastructure; D014934:Wood / Q000378:metabolism*; D014961:X-Ray Diffraction; D014990:Xylans / Q000378:metabolism*; D052584:Xylem / Q000201:enzymology / Q000648:ultrastructure; D001616:beta-Galactosidase / Q000235:genetics / Q000378:metabolism
chemical_list: D005936:Glucans; D014990:Xylans; C029353:xyloglucan; D002482:Cellulose; D044602:Cellulases; D006026:Glycoside Hydrolases; C072818:xyloglucan endo(1-4)-beta-D-glucanase; D001616:beta-Galactosidase; D043364:Endo-1,4-beta Xylanases