Contact:
sales@biotechnologyforums.com to feature here

Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Genetically modified trees: easier paper and biofuel production
#1
One of the main barriers to efficient processing of wood to give paper and biofuel is lignin, an aromatic polymer which makes up a large proportion of plant cell walls. Lignin contains ether bonds that are difficult to break, creating difficulties for biofuel and paper production as the lignin must currently be removed at considerable environmental and economic cost. However researchers at the University of British Columbia, the University of Wisconsin-Madison, Michigan State University, funded by Great Lakes Bioenergy Research Center, have made a breakthrough by genetically engineering poplar trees with modified lignin, containing more easily broken ester linkages. The study is published today in the journal Science.

In the study, the researchers isolated a gene for an enzyme called transferase which works by forming monolignol ferulate conjugates. These conjugates when used by the tree in lignin production results in introduction of the more easily broken ester linkages in the lignin. While previous studies had attempted to address the problem by reducing the quantity of lignin in trees by suppressing genes, this often resulted in stunted growth or susceptibility of the trees to weather conditions or pathogens. The strength of this study was that introduction of the transferase gene into the trees and consequent production of more easily broken down lignin left the strength and structure of the modified poplars intact. Dr Shawn Mansfield of the University of British Columbia, an author on the study, said: "It is truly a unique achievement to design trees for deconstruction while maintaining their growth potential and strength."

Removal of lignin from trees in production of biofuels and paper currently requires high energy expenditure and use of chemicals and results in production of environmental pollutants. These genetically modified poplars could be processed with less chemicals and energy. The new technique also means more effective recovery of lignin which can be used in other applications, for example adhesives, insolation, carbon fibres and paint additives.

The strategy adopted in this study would be transferable to other plants such as grasses, with potential to develop new biofuel sources as alternatives to petroleum. The authors acknowledge that genetic modification of plants is a controversial topic but point out that various strategies can be adopted to ensure that genes do not spread to the forest. These include growing crops away from native stands, introducing genes to make the trees or plants sterile and harvesting before reproductive maturity is reached. Eventually, they envisage the trees being planted like an agricultural crop rather than in native forests. Poplar in particular has potential as a biofuel crop as it grows rapidly and on marginal farmland.

Dr Mansfield concludes: "We're a petroleum reliant society… We rely on the same resource for everything from smartphones to gasoline. We need to diversify and take the pressure off of fossil fuels. Trees and plants have enormous potential to contribute carbon to our society."

Sources:

Wilkerson, C.G., Mansfield, S.D., Lu,F., Withers, S., Park, J.-Y., Karlen, S. D., Gonzales-Vigil, E., Padmakshan, D., Unda, F., Rencoret, J. and Ralph, J. Monolignol Ferulate Transferase Introduces Chemically Labile Linkages into the Lignin Backbone. Science 4 April 2014: Vol. 344 no. 6179 pp. 90-93; DOI: 10.1126/science.1250161

Press release: University of British Colombia; available at http://www.eurekalert.org/pub_releases/2...040314.php [Accessed 3 April 2014].
Like Post Reply
  




Users browsing this thread:
1 Guest(s)

Genetically modified trees: easier paper and biofuel production00