Scientists succeeded in producing 580 mg of gasoline per litre of cultured broth by converting in vivo (on living subject) generated fatty acid.
For many decades, we have been relying on fossil resources to produce liquid fuels such as gasoline, diesel, and many industrial and consumer chemicals for daily use, researchers said.
Gasoline, the petroleum-derived product that is most widely used as a fuel for transportation, is a mixture of hydrocarbons, additives, and blending agents.
The hydrocarbons, called alkanes, consist only of carbon and hydrogen atoms. Previously, through metabolic engineering of Escherichia coli (E coli), there have been a few research results on the production of long-chain alkanes, which consist of 13-17 carbon atoms, suitable for replacing diesel.
However, there has been no report on the microbial production of short-chain alkanes, a possible substitute for gasoline.
A Korean research team led by Professor Sang Yup Lee of the Department of Chemical and Biomolecular Engineering at the Korea Advanced Institute of Science and Technology (KAIST) reported, for the first time, the development of a novel strategy for microbial gasoline production through metabolic engineering of E coli.
Researchers engineered the fatty acid metabolism to provide the fatty acid derivatives that are shorter than normal intracellular fatty acid metabolites, and introduced a novel synthetic pathway for the bio-synthesis of short-chain alkanes.
This allowed the development of platform E coli strain capable of producing gasoline for the first time. Furthermore, this platform strain, if desired, can be modified to produce other products such as short-chain fatty esters and short-chain fatty alcohols.
"It is only the beginning of the work towards sustainable production of gasoline. The titre is rather low due to the low metabolic flux towards the formation of short-chain fatty acids and their derivatives," Lee said.
"We are currently working on increasing the titre, yield and productivity of bio-gasoline. Nonetheless, we are pleased to report, for the first time, the production of gasoline through the metabolic engineering of E coli, which we hope will serve as a basis for the metabolic engineering of microorganisms to produce fuels and chemicals from renewable resources," said Lee. The study was published in the journal Nature.