Engineering the cell wall by reducing de-methyl-esterified homogalacturonan improves saccharification of plant tissues for bioconversion.
Plant cell walls represent an abundant, renewable source of biofuel and other useful products. The major bottleneck for the industrial scale-up of their conversion to simple sugars (saccharification), to be subsequently converted by microorganisms into ethanol or other products, is their recalcitrance to enzymatic saccharification. We investigated whether the structure of pectin that embeds the cellulose-hemicellulose network affects the exposure of cellulose to enzymes and consequently the process of saccharification. Reduction of de-methyl-esterified homogalacturonan (HGA) in Arabidopsis plants through the expression of a fungal polygalacturonase (PG) or an inhibitor of pectin methylesterase (PMEI) increased the efficiency of enzymatic saccharification. The improved enzymatic saccharification efficiency observed in transformed plants could also reduce the need for acid pretreatment. Similar results were obtained in PG-expressing tobacco plants and in PMEI-expressing wheat plants, indicating that reduction of de-methyl-esterified HGA may be used in crop species to facilitate the process of biomass saccharification.
Lionetti
Vincenzo
V
Dipartimento di Biologia Vegetale, Istituto Pasteur Fondazione Cenci Bolognetti, Sapienza Università di Roma, Piazzale Aldo Moro 5, 00185 Rome, Italy.
Francocci
Fedra
F
Ferrari
Simone
S
Volpi
Chiara
C
Bellincampi
Daniela
D
Galletti
Roberta
R
D'Ovidio
Renato
R
De Lorenzo
Giulia
G
Cervone
Felice
F
D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics* / Q000502:physiology; D001234:Aspergillus niger / Q000235:genetics; D056804:Biofuels; D018533:Biomass; D002265:Carboxylic Ester Hydrolases / Q000235:genetics; D002473:Cell Wall / Q000187:drug effects / Q000502:physiology*; D002482:Cellulose / Q000378:metabolism / Q000494:pharmacology; D017931:DNA Primers; D005822:Genetic Vectors; D018546:Hypocotyl / Q000378:metabolism; D010368:Pectins / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D059828:Plant Cells; D018515:Plant Leaves / Q000378:metabolism; D018521:Plant Physiological Phenomena; D010940:Plant Proteins / Q000235:genetics; D011096:Polygalacturonase / Q000378:metabolism; D011134:Polysaccharides / Q000378:metabolism / Q000494:pharmacology; D018749:RNA, Plant / Q000235:genetics; D023822:Tissue Engineering / Q000379:methods*; D014026:Nicotiana / Q000235:genetics* / Q000502:physiology
D056804:Biofuels; D017931:DNA Primers; D010940:Plant Proteins; D011134:Polysaccharides; D018749:RNA, Plant; C007916:hemicellulose; D010368:Pectins; D002482:Cellulose; D002265:Carboxylic Ester Hydrolases; C022323:pectinesterase; D011096:Polygalacturonase; C003181:polygalacturonic acid