The Escherichia coli bacteria have a bad reputation. For one, the bacterium is more known for its strains that cause food poisoning, urinary tract infection, diarrhea and other illnesses but British and Finnish scientists have come up with a way to utilize the bacteria to generate green energy.
In a new study published in Nature Communications on Sept. 2, Patrik Jones, from the Imperial College London, and colleagues, used E.coli bacteria to interrupt fatty acid synthesis, a process that converts fatty acids into cell membranes. By using special enzymes, the researchers were able redirect the fatty acids so that instead of producing cell membranes, the bacteria produces renewable propane.
"Fatty acids are normally synthesized mainly in order to generate cell membranes but, by introducing a special enzyme, we can redirect it to instead release butyric acid, the precursor for propane," Jones explained. "From there, only two more enzymes were needed in order to convert this smelly fatty acid into propane."
Jones said that the process involves introduction of only five E. coli genes, which is considered a very tiny fraction of over 4,000 genes that can be found the entire genome of the bacteria. As to why they have chosen to develop renewable propane, the researchers said that the fuel can be separated from natural process without requiring much energy. Propane can also be used with existing infrastructure.
"Propane, the bulk component of liquid petroleum gas, is an appealing target as it already has a global market. In addition, it is a gas under standard conditions, but can easily be liquefied," the researchers wrote. "This allows the fuel to immediately separate from the biocatalytic process after synthesis, yet does not preclude energy-dense storage as a liquid."
The researchers said that their findings could pave way to the commercial production of a renewable fuel that could potentially replace limited fossil fuel reserves.
"Fossil fuels are a finite resource and as our population continues to grow we are going to have to come up with new ways to meet increasing energy demands," Jones said. "It is a substantial challenge, however, to develop a renewable process that is low-cost and economically sustainable."
Jones also said that the propane produced using E.coli is already engine-ready albeit he acknowledged that the amount of fuel his team has produced is way lesser than what is required to make it into a commercial product. Nonetheless, he said that they currently work on refining the process.
