Lignin engineering to improve saccharification and digestibility in grasses

The digestibility of plant biomass has a major influence on its value as a forage for livestock and as a feedstock for industrial biotechnology. For both processes, the concentration, structure and composition of lignin influence the accessibility of wall carbohydrate polymers to microbes and digestive enzymes during biochemical decomposition. Although lignin engineering has been less tractable in monocots than in model dicots, a body of work is accumulating on the effects of manipulating lignin biosynthesis in energy grasses and cereal crops. In addition to conventional targets for lignin engineering, several novel features of grass lignin have recently become amenable to targeted manipulation through the identification of genes involved in their synthesis.