Different Routes for Conifer- and Sinapaldehyde and Higher Saccharification upon Deficiency in the Dehydrogenase CAD1
| Autor: | Wout Boerjan, Sandrien Desmet, Cliff E. Foster, Lennart Hoengenaert, Catherine Lapierre, Kris Morreel, Frédéric Legée, Nicholas Santoro, Rebecca Van Acker, John Ralph, Françoise Laurans, Hoon Kim, Geert Goeminne, Annabelle Déjardin, Gilles Pilate, Ruben Vanholme |
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| Přispěvatelé: | Department of plant Biotechnology and Bioinformatics, University of Gent, Flanders Institute for Biotechnology, Unité de recherche Amélioration, Génétique et Physiologie Forestières (AGPF), Institut National de la Recherche Agronomique (INRA), Department of Energy, Great Lakes Bioenergy Research Center (GLBRC), Department of Biochemistry, University of Wisconsin-Madison, Institut Jean-Pierre Bourgin (IJPB), Institut National de la Recherche Agronomique (INRA)-AgroParisTech |
| Jazyk: | angličtina |
| Rok vydání: | 2017 |
| Předmět: |
Models
Molecular 0106 biological sciences 0301 basic medicine DOWN-REGULATION Magnetic Resonance Spectroscopy [SDV.BIO]Life Sciences [q-bio]/Biotechnology Sinapaldehyde Physiology Cinnamyl-alcohol dehydrogenase Plant Science Alkalies CINNAMYL-ALCOHOL-DEHYDROGENASE Xylose Lignin 01 natural sciences 7. Clean energy Ferulic acid chemistry.chemical_compound Cell Wall Tandem Mass Spectrometry Biomass Acrolein GENE-EXPRESSION Pigmentation food and beverages Plants Genetically Modified CAFFEOYL SHIKIMATE ESTERASE Phenotype Populus Biochemistry Carbohydrate Metabolism Energy source Oxidation-Reduction Metabolic Networks and Pathways LIGNIN Lignocellulosic biomass TRANSGENIC POPLAR 03 medical and health sciences Hydrolysis Phenols Biochemistry and Metabolism STATE 2D NMR Genetics MONOLIGNOL BIOSYNTHESIS Methanol fungi Biology and Life Sciences BIOSYNTHETIC-PATHWAY Alcohol Oxidoreductases Tracheophyta 030104 developmental biology Solubility O-METHYLTRANSFERASE ACTIVITY chemistry ARABIDOPSIS-THALIANA 010606 plant biology & botany |
| Zdroj: | Plant Physiology Plant Physiology, American Society of Plant Biologists, 2017, 175 (3), pp.1018-1039. ⟨10.1104/pp.17.00834⟩ PLANT PHYSIOLOGY |
| ISSN: | 0032-0889 1532-2548 |
| DOI: | 10.1104/pp.17.00834⟩ |
| Popis: | article en open access; International audience; In the search for renewable energy sources, genetic engineering is a promising strategy to improve plant cell wall composition for biofuel and bioproducts generation. Lignin is a major factor determining saccharification efficiency and, therefore, is a prime target to engineer. Here, lignin content and composition were modified in poplar (Populus tremula 3 Populus alba) by specifically down-regulating CINNAMYL ALCOHOL DEHYDROGENASE1 (CAD1) by a hairpin-RNA-mediated silencing approach, which resulted in only 5% residual CAD1 transcript abundance. These transgenic lines showed no biomass penalty despite a 10% reduction in Klason lignin content and severe shifts in lignin composition. Nuclear magnetic resonance spectroscopy and thioacidolysis revealed a strong increase (up to 20-fold) in sinapaldehyde incorporation into lignin, whereas coniferaldehyde was not increased markedly. Accordingly, ultra-high-performance liquid chromatography-mass spectrometry-based phenolic profiling revealed a more than 24,000-fold accumulation of a newly identified compound made from 8-8 coupling of two sinapaldehyde radicals. However, no additional cinnamaldehyde coupling products could be detected in the CAD1-deficient poplars. Instead, the transgenic lines accumulated a range of hydroxycinnamate-derived metabolites, of which the most prominent accumulation (over 8,500-fold) was observed for a compound that was identified by purification and nuclear magnetic resonance as syringyl lactic acid hexoside. Our data suggest that, upon down-regulation of CAD1, coniferaldehyde is converted into ferulic acid and derivatives, whereas sinapaldehyde is either oxidatively coupled into S'(8-8) S' and lignin or converted to sinapic acid and derivatives. The most prominent sink of the increased flux to hydroxycinnamates is syringyl lactic acid hexoside. Furthermore, low-extent saccharification assays, under different pretreatment conditions, showed strongly increased glucose (up to +81%) and xylose (up to +153%) release, suggesting that down-regulating CAD1 is a promising strategy for improving lignocellulosic biomass for the sugar platform industry. |
| Databáze: | OpenAIRE |
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