title: Biomass derived from transgenic tobacco expressing the Arabidopsis CESA3ixr1-2 gene exhibits improved saccharification.
abstract: Studies in Arabidopsis thaliana and Nicotiana tabacum L. variety Samsun NN demonstrated that expression of the CESA3 cellulose synthase gene that contains a point mutation, named ixr1-2, results in greater conversion of plant-derived cellulose to fermentable sugars. The present study was designed to examine the improved enzymatic saccharification efficiency of lignocellulosic biomass of tobacco plants expressing AtCESA3ixr1-2. Three-month-old AtCESA3ixr1-2 transgenic and wild-type tobacco plants (Nicotiana tabacum L. variety Samsun NN) were grown in the presence and absence of isoxaben. Biomass obtained from leaf, stem, and root tissues were analyzed for enzymatic saccharification rates. During enzymatic saccharification, 45% and 25% more sugar was released from transgenic leaf and stem samples, respectively, when compared to the wild-type samples. This gain in saccharification efficiency was achieved without chemical or heat pretreatment. Additionally, leaf and stem biomass from transgenic AtCESA3ixr1-2 requires a reduced amount of enzyme for saccharification compared to biomass from wild-type plants. From a practical standpoint, a similar strategy could be employed to introduce the mutated CESA into energy crops like poplar and switchgrass to improve the efficiency of biomass conversion.
authors.affiliation: University of Kentucky KTRDC, College of Agriculture, Food and Environment Lexington KY 40546-0236 USA.
authors.forename: Dipak Kumar
authors.initials: DK
authors.lastname: Sahoo
authors.affiliation: University of Kentucky KTRDC, College of Agriculture, Food and Environment Lexington KY 40546-0236 USA.
authors.forename: Indu B
authors.initials: IB
authors.lastname: Maiti
mesh_terms: D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D001549:Benzamides / Q000494:pharmacology; D018533:Biomass; D002482:Cellulose / Q000378:metabolism*; D005285:Fermentation; D018506:Gene Expression Regulation, Plant; D005964:Glucosyltransferases / Q000235:genetics / Q000378:metabolism*; D006540:Herbicides / Q000494:pharmacology; D006868:Hydrolysis; D018515:Plant Leaves / Q000201:enzymology / Q000235:genetics / Q000254:growth & development; D018517:Plant Roots / Q000201:enzymology / Q000235:genetics / Q000254:growth & development; D018547:Plant Stems / Q000201:enzymology / Q000235:genetics / Q000254:growth & development; D030821:Plants, Genetically Modified / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D017354:Point Mutation; D013997:Time Factors; D014026:Nicotiana / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development
chemical_list: D029681:Arabidopsis Proteins; D001549:Benzamides; D006540:Herbicides; C057467:isoxaben; D002482:Cellulose; C516179:At5g05170 protein, Arabidopsis; D005964:Glucosyltransferases
keywords: AtCESA3ixr1-2; Nicotiana tabacum; biofuel; biomass