Knowledge Based Bio-Economy

RENEWALL

Understanding plant cell wall synthesis

Project Acronym: RENEWALL

Title of project: Improving plant cell walls for use as a renewable industrial feedstock

Research area: Plant cell walls - understanding plant cell walls for optimizing biomass potentia

Contract No: 211982

EU Contribution: 5 744 122 EURO

Start date: 01-08-2008

Duration: 48 Months

Objectives

With oil reserves diminishing and the effects of industrial emissions on global climate, there is a need for renewable carbon-neutral industrial feedstocks. First generation biorefineries, producing biofuels and bioplastics through fermentation of sugar or starch have shown rapid expansion. Since these feedstocks are derived from conventional food crops this has led to concerns about competition with food. A more sustainable option is to use plant biomass in the form of agricultural by-products or residues abundant sources of which are underutilized and can be supplemented by purpose grown dedicated energy crops. Such raw materials are composed largely of cell wall polysaccharides. Conversion of these polysaccharides to sugars could potentially provide cheap and abundant substrates for industrial biotechnology. The use of plant biomass in this way is hampered by the high cost of conversion (saccharification) reflecting the resistance of plant cell walls to rapid enzymatic hydrolysis. This project aims to find ways to overcome this technical bottleneck by identifying and modifying the structural features of plant cell walls that make them difficult to process. Combining genomics, transcriptomics, proteomics, and systems approaches, it will increase understanding of the biosynthesis of the major components of plant biomass, (lignin, cellulose and matrix polysaccharides. It aims to identify new genes that can be manipulated to improve the ease and yield of biomass saccharification and will generate rational approaches for improving the quality of plant biomass as an industrial feedstock.

Expected Impact

Overall, the project should develop novel strategies for genetic engineering of cell walls for improved saccharification by simultaneously targeting several bottlenecks in the process. It will increase understanding of cellulose biosynthesis to a level where predictive approaches using reverse genetics can be used to improve the digestibility of cellulose by decreasing its crystallinity without compromising its overall mechanical function in the cell wall. It should make a significant impact on the potential to breed energy crops that are easier to breakdown to their constituent sugars which can then be used as fermentation feedstock. This could impact on the development of the European biofuels initiative by reducing the cost of feedstock as well as reducing concerns about competition between use of potential food plants for fuel. It could also impact the European fermentation industry in general yielding lower cost substrates. However, if the improved plants are generated through genetic manipulation the longer term impact will depend on the attitude to allowing genetically modified organisms in the various Member States.

Expected Results

The project expects to identify molecular bottlenecks in the enzyme-based saccharification process based on analyses of both existing germplasm as well as on new mutant populations and novel materials generated during the course of the work, overall identifying the molecular and genetic barriers of importance. A greater understanding of lignin biosynthesis will aid manipulation in order to optimise saccharification. It will characterise mutants/transgenics with altered lignin to determine how the content and structure of lignin influences saccharification. The capability for rational design of lignocellulosics improved for saccharification should be increased through use of new tools (systems biology; microarray co-expression) to effect a step change in understanding of lignification in grasses by identifying and manipulating lignin biosynthesis genes in Brachypodium. The work will also establish the relative importance of various structural characteristics of hemicelluloses in terms of saccharification potential by identifying novel enzymes involved in key steps in biosynthesis of matrix polysaccharides. The use of transcriptomic and proteomic approaches will identify key biosynthetic enzymes, establishing levels, degree of acetylation and quantity of polysaccharide-lignin links that can be altered in plant materials. The value of using of microbial proteins and modules, tested both in vitro during the saccharification process, and in transgenic, Brachypodium, Arabidopsis and poplar should be established.

Website of project: http://www.renewall.eu/

Contacts:

Coordinator: Simon Mcqueen-Mason, sjmm1@york.ac.uk

Organisation University of York (UK), http://www.cnap.org.uk/

Partners:

University of Dundee, UK, http://www.lifesci.dundee.ac.uk/ps

Københavns Universitet, Denmark, http://www.plbio.life.ku.dk/

Kungliga Tekniska Hoegskolan, Sweden, http://www.biotech.kth.se/glycoscience/Main_Page

Institut National de la Recherche Agronomique, France, http://www.angers-nantes.inra.fr/

University of Newcastle upon Tyne, UK, http://www.ncl.ac.uk/

Universite Paul Sabatier Toulouse III, France, http://www.ups-tlse.fr/

University of Cambridge, UK, http://www.bio.cam.ac.uk/~dupree/

University of Manchester, UK, http://www.ls.manchester.ac.uk/

Sveriges Lantbruksuniversitet, Sweden, http://www.upsc.se/

VIB, Belgium, http://www.psb.ugent.be/

KWS SAAT AG , Germany, http://www.kws.de/

Swetree Technologies AB, Sweden, http://swetree.com/

DLF - Trifolium AS, Denmark, http://www.dlf.com/

Cornell University, USA, http://mbg.cornell.edu/cals/mbg/