Engineering Secondary Cell Walls in Plants
The polysaccharide polymers of plant cell walls provide a carbon and energy source for biofuel production, but they are embedded in lignin, which gives plants their required rigidity but is also primarily responsible for the recalcitrance of plant biomass to enzymatic hydrolysis. Previous attempts to engineer reduced lignin content in plants were imprecise and resulted in unacceptable negative impacts on plant growth because of vessel integrity loss. In this work, researchers engineered lignin and polysaccharide biosynthesis in a cell-type specific manner such that lignin was greatly reduced in the normally lignin-rich fiber cells, and the amount of polysaccharide polymers was much greater in vessel cells. The resulting plants were viable and grew normally. When biomass from these engineered plants was subjected to enzymatic digestion, more sugars were released than from wild-type plants, a desirable trait for biofuels production.
Yang, F., P. Mitra, L. Zhang, L. Prak, Y. Verhertbruggen, J.-S. Kim, L. Sun, K. Zheng, K. Tang, M. Auer, H. V. Scheller, and D. Loque. 2013. “Engineering Secondary Cell Wall Deposition in Plants,” Plant Biotechnology Journal 11, 325–335. DOI: 10.1111/pbi.12016.