EXPLOITING WILLOW METABOLITES AND PATHWAYS FOR THE BIO-ECONOMY
Engaging plant carbon metabolism to supplement petro-chemical derived feedstocks and high value products
Sunday, January 1, 2012 - 12:30
- Rothamsted Research Technology Innovation Programme (TIP)
Willows (Salix sp.) are fast growing woody plants that are an established commercial crop, grown for harvesting for combustion in biomass boilers, as well as for a number of traditional uses such as basket-making and the production of herbal medicines. However, this genus of plants (the Salicaceae) also produces and accumulates a variety of chemicals, mainly based on phenolic glycoside structures that potentially can add value to the crop. Salix metabolites have a number of potential economic uses across a range of industries from basic chemicals (e.g. ingredients for resins and polymers) to high value pharmaceuticals. The project studies the diversity of chemistry found across the Salicaceae, defines the biosynthetic pathways leading to those metabolites, and exploits genetic collections and Rothamsted expertise in willow breeding, genetics and agronomy with the aim of producing a new generation of dual-purpose biomass crops, tailor-made for production of valuable chemicals in addition to current bioenergy uses.
The National Willow Collection (circa 1500 different accessions) and mapping populations (up to 1000 lines each) have been assembled at Rothamsted as part of a breeding programme for high biomass yield and pest resistant traits. In this project, the diversity of chemistry across these collections is being mapped by application of NMR and LC-MS metabolomics technologies and an associated natural product discovery programme that includes pharmaceutical activity assessment, is building on the historical use of willow bark as a medicine. The biosynthetic pathway in Salix leading to a variety of phenolic glycosides is being delineated and the genes responsible are being identified by a combined metabolomics-transcriptomics approach. Working with specialists in willow genetics and genomics, we are identifying key genes and utilising them in a metabolic engineering programme to produce designer willow and poplar (a close relative) plants for future farming for the production of high value chemicals. We are covering a chemical space that includes phenolic glycosides and terpenoid pathways, and we also study carbon partitioning into these secondary products, particularly in relation to biomass and lignin accumulation, which occurs via related pathways. Our current strategic interests include novel willow pharmaceuticals in the oncology and neuroscience areas, as well as production of specialist chemicals for resin, polymer and adhesive applications.
The project generates species specific metabolite signatures and associated bioactivity data.
Additionally, a panel of isolated, characterised novel molecules is available for pharmacological testing