team of researchers led by Professor Nigel Scrutton, director of the Manchester Institute of Biotechnology, and Dr. Patrik Jones from Imperial College of London, have developed a new metabolic pathway for the biosynthesis of propane gas, a relatively clean fuel, by genetically engineering an enzyme found in algae. The team’s method was published in the journal Biotechnology of Biofuels.
In nature, enzymes are proteins that act as catalysts and help complex reactions occur, such as digestion and photosynthesis, often breaking down large molecules into smaller ones.
Propane is easily stored and transported, and there is already a market for it, so a renewable form of it would be not only promising economically but also good for the environment.
There is no natural way to make small-chain hydrocarbon propane, so the team first had to identify an enzyme that was capable of working with large hydrocarbon molecules, and then edit its genome. They used an enzyme found in algal cyanobacteria that researchers have previously employed to catalyze a reaction in order to form butanol (C4H9OH). It was then genetically engineered to make it capable of carrying out a reaction to convert a natural cell substrate into propane gas (C3H8) instead of butanol.
“We take a natural enzyme, we re-engineer it to do a different type of chemistry with a different small molecule specificity,” said Professor Scrutton. “Having done that, we can then use metabolic engineering to make an artificial pathway that then converts that into propane gas.”