Plant Genetic Modification and the pSAT Vector System
Genetic modification of plants is carried out by introducing certain specific genes from different sources into the plant genome. This is done to give plants certain characteristics that either make them excellent food producers or make them resistant to pests and diseases. In recent years, scientists have also been using genetic engineering for tapping the potential of plants as providers of bio-fuel. Production of bio-fuel from plants may help ease the concerns about fossil fuel shortage and whether the oil industry will run out of oil.
Introducing different genes in a plant is one thing, but to get them to express simultaneously is another matter. Production of proteins by activated genes is called gene expression. Researchers have now devised a way to bring this about by using an advanced plant genetic engineering molecular tool called the modular satellite (pSAT) vector system. It allows for the simultaneous expression of multiple genes.
Modifying Plant Genes for Biofuel Production
In April 2009, scientists at the U.S. Department of Energy’s Brookhaven National Laboratory published a study in Plant Molecular Biology about a family of plant genes that may help step up biofuel production from plants. The scientists researched and identified 61 genes from the leafy Arabidopsis and 94 genes from the woody Poplar trees. They then studied how these genes, once they were activated, instructed plant cells to make different enzymes.
The researchers were particularly interested in the enzymes that helped build the cell walls in the woody plant tissues. These cell walls are bound and strengthened by acyl group molecules. The acyl groups prevent an easy breakdown of cell walls, and, in biofuel production, the cell walls must be broken down to make sugar.
Once the scientists discover the exact building enzymes connected with the acyl groups, they can apply genetic engineering and modify cell wall formation. This would lead to plants whose biofibers could be easily broken down and converted to sugar. It would step up biofuel production.
Biofuel Building Block HMF
While genetic engineering can make it easier to derive sugar from plant cellulose, there are still a couple of steps required to convert that sugar into biofuel. The sugar derived from the cellulose has to be converted into 5-hydroxymethylfurfural, more conveniently known as HMF. This is a building block for biofuels. It is also found in regular fossil fuels. It takes time and expense to derive first the sugar and the HMF from the sugar and then the biofuel from the HMF.
Now researchers from the Pacific Northwest National Laboratory, a research center belonging to the U.S. Department of Energy, have devised a way to make HMK directly from cellulose, without bothering with the sugar-making step.
They used a combination of metal chlorides and an ionic liquid solvent to break down cellulose. It only takes one step to convert cellulose to HMK, and the metal chlorides and the ionic liquid can be recycled for repeated future use. This is both time-saving and resource-saving.