GM tobacco plants can produce bio-fuels

Genetically modified tobacco plants are viable as raw material for producing bio-fuels, a new study has found.
Scientists have demonstrated, for the first time, the viability of using specific tobacco proteins (known as thioredoxins) as biotechnological tools in plants.
Researchers have managed to increase the amount of starch produced in the tobacco leaves by 700 per cent and fermentable sugars by 500 per cent.
Thioredoxins (Trx) are small proteins present in most living organisms.
Ruth Sanz-Barrio, an agricultural engineer of the NUP/UPNA-Public University of Navarre, demonstrated the capacity of the thioredoxins f and m in tobacco as biotechnological tools to increase the starch content in the plant.

Thioredoxin f was shown for the first time in vivo to be more efficient than Trx m in regulating the metabolism of carbohydrates, as it causes "a significant increase in the amount of starch in the leaves, which can reach 700 per cent with respect to the amount obtained from non-modified control plants."

Ruth Sanz explained that this was also new, since "up until now both Trxs were thought to act in the same way, but we have shown that this is not so."
Once the regulating function of Trx f in starch synthesis had been proven, the researchers focussed on its possible application in energy crops used to produce bio-ethanol.

"We saw that the leaves of the genetically modified tobacco plants were releasing 500 per cent more fermentable sugars.
"With these sugars, which could later be turned into bioethanol, one could obtain up to 40 litres of bioethanol per tonne of fresh leaves -according to the theoretical calculation provided by the National Centre for Renewable Energies where the enzymatic test was conducted," said Ruth Sanz.
This would mean an almost tenfold increase in bioethanol yield with respect to the control tobacco plant that had not been modified, researchers said.