Biology Department Seminar

Lignocellulosics are an essential component of the nation’s energy strategy for ethanol because they can be produced in very large scale. However, current lignocellulosics have several barriers. Foremost is the quality and composition of lignin, which limits the accessibility of cellulose. Secondly, the cellulose itself is high in crystallinity, thereby reducing saccharification efficiency. Thirdly, low cellulose content in natural populations and that the hemicellulose composition is substantially less than optimal further work against a more feasible conversion economics. Based on previous results, trees may be modified in cell wall composition far beyond the barriers of natural variation within any species. This has generated substantial information that could be applied to other lignocellulosics, however, much new knowledge is needed. We do not yet have an adequate understanding of the genetic regulatory networks and molecular interactions involved in the synthesis of plant cell walls. Trees are the only target energy crop that would allow investigations at the genome level for such knowledge. This is because of the genome sequence of Populus trichocarpa and the recent availability of an efficient genetic transformation system for the sequenced genotype. The paradigm is an iterative functional genomic approach, where genomics is used to identify candidate genes in transgenics, and transformation is used to create new transgenics to test the genomic inferences for cell wall biosynthesis. We envision the use of trees to establish an integrated systems-based genomic model where the lignocellulosic and the process are coherently designed together for an optimized and high efficiency ethanol production.