Author
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Ralph, John |
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Submitted to: Meeting Abstract
Publication Type: Abstract Only Publication Acceptance Date: 9/20/2007 Publication Date: N/A Citation: N/A Interpretive Summary: Technical Abstract: The effects on lignification of perturbing most of the genes for enzymes on the monolignol biosynthetic pathway have now been reasonably well studied, particularly in angiosperms. Early studies sought to reduce lignin content with the idea of targeting the key barrier to efficient utilization of plant cell walls in a variety of natural (e.g., ruminant digestibility) and industrial (e.g., chemical pulping, biomass conversion to ethanol) processes. More recently, and particularly for pulping and biomass conversion to ethanol, the idea of altering the composition and structure of the lignin, without necessarily reducing the amount, has also become attractive. The latter approach arose from noting the resilience of the lignification pathway, and its metabolic plasticity. Some transgenics with diminished capacity for biosynthesis of the normal lignin monomers responded by incorporating other available phenolic monomers (often, but not always, pathway intermediates and their derived products) into the polymer. Plant cell wall integrity and plant growth may be impacted, but not always seriously. Obviously, incorporating new phenolics into lignin produces a polymer with a different structure and, therefore, different chemical and physical properties. Not surprisingly, some of these modifications allow for improved biomass conversion efficiencies. This talk will explore the structural changes that result from perturbing the various genes in the lignin biosynthetic pathway and highlight the implications for cell wall utilization. |
