Mr Stefan Ferreira
Lignin and cellulose are the two most abundant terrestrial polymers on Earth and has many uses, such as a dispersant in concrete or dyes, as an emulsifier, a chelating agent for fertilizers or oil drilling fluids and micronutrient fertilisers, a raw material for chemical production, and a binder for animal feed and road dust control. The problem with lignin is the majority of products humans tend to use, bar timber uses, requires us to remove or break down most of the lignin from trees.
There has been a lot of work focusing on reducing or alter the lignin levels and S:G ratios in plants, alter the structure, or by using substitutes for monolignols, in an effort to facilitate pulping, improve forage digestibility, or overcome recalcitrance for bioenergy feedstocks. Most of the enzymes involved in the shikimate and phenylpropanoid pathway have been altered or down-regulated in experiments to reduce lignin levels and many successes have been made in reducing lignin content or composition
Yet very little research has been done on altering gene expression of Calvin cycle or Pentose Phosphate Pathway (PPP) genes. Transketolase (TK) and Transaldolase (TAL) are genes found in the Calvin cycle and PPP. There is evidence to suggest that perturbing expression of of these genes can affect lignin composition and increase saccharification efficiency. This study will focus on how TK1, TK2, and TAL affects primary carbon metabolism, and secondary cell wall formation, and investigate if there might be a biotechnological application in knock-outs or knock-downs of these genes.