image: Introducing really cleavable linkages into the lignin polymer backbone. Lignins are polymers integral to plant cell walls derived from combinatorial radical polymerization of hydroxycinnamyl alcohol monomers. Delignification requires cleavage of the polymer into smaller soluble units, but breaking even the weakest backbone bonds requires stringent chemical conditions. We have induced plants to synthesize monolignol ferulate conjugates in their monomer pool, by using a gene from Chinese Angelica, and to utilize them for lignification. Using a xylem-specific promoter, the protein is targeted explicitly to the vascular tissue of the leaf (as shown here by the fluorescence) and, of course, in the wood. This produces lignins that are more easily depolymerized, providing less energy-demanding access to the valuable plant polysaccharides. This image relates to a paper that appeared in the 4 April, 2014, issue of Science, published by AAAS. The paper, by Curtis Wilkerson at Michigan State University in East Lansing, MI, and colleagues was titled, "Monolignol Ferulate Transferase Introduces Chemically Labile Linkages into the Lignin Backbone." view more
Credit: [Photo by Shawn Mansfield, UBC, and editing by Matt Wisniewski, Media Specialist, Great Lakes Bioenergy Research Center, Madison, WI]