Edinburgh, Scotland, United Kingdom - TAIR

Systems biology of lignification and relevance
to biofuels
With increasing concerns about global warming and energy security, it is
important to reduce dependence on fossil fuels. Biofuels are widely accepted to
be a valuable alternative to achieve part of this objective. Bioethanol, as one of
the major biofuels, is nowadays mainly made from food crops such as maize
and sugarcane. However, much higher energy efficiencies are expected when
bioethanol could be derived from lignocellulosic material such as wood or straw.
This process, which includes fermentation after acid or enzymatic hydrolysis of
the cell wall polysaccharides, is expensive due to some practical hindrances.
One of the major barriers is lignin, an aromatic polymer and important
component of the secondary cell wall. Lignin reduces access of enzymes and
chemicals to cell wall polysaccharides, thus reducing the efficiency of hydrolysis.
A solution to this issue is designing tailor-made lignin in biomass crops, in order
to make the cell wall more applicable for processing, without introducing
detrimental effects on plant growth. To succeed in this fragile balance-exercise,
system-wide knowledge about lignification is needed.
We used Arabidopsis as a model species to determine the effects of altering
lignin composition and content on both plant growth and biofuel processing
efficiency, and to obtain insight into the cross-talk between lignin biosynthesis
and other metabolic pathways and processes. A complete set of mutants, each
defective in a lignin biosynthetic step, is investigated by transcriptomics (via
microarrays) and metabolomics (via GC/MS and LC/UV-MS). The data reveal
that genetic modification of monolignol biosynthesis in the cell wall has wideranging
consequences on a number of metabolic processes. Molecular insight
into these pleiotropic effects is essential if we want to design cell walls for end
use applications.
94
C43
Saturday 14:30 - 15:00
Bioenergy
Ruben Vanholme
Veronique Storme
Kris Morreel
Jorgen Christensen
Antje Rohde
Geert Goeminne
Rebecca Van Acker
Eric Messens
Wout Boerjan
VIB Department of Plant
Systems Biology
Gent
Ghent
Belgium