Researchers have designed an entire molecular “assembly line” in bacterial cells that pieces together a kind of alcohol that isn’t normally made by known living organisms. This alcohol could serve as a biofuel that, unlike ethanol, has a high energy density and could be used in gasoline and jet fuel.
While the engineered bacteria are not yet efficient enough to produce biofuel on a commercial scale, the work shows that microbes can be designed to make chemicals that are beyond life’s natural repertoire, the researchers report online December 8 in Proceedings of the National Academy of Sciences.
“Previous metabolic engineering work typically produces compounds that already exist in nature,” says coauthor James Liao, a biomolecular engineer at the University of California, Los Angeles. “Our work here aims to produce compounds that are not synthesized in nature.”
Since the 1970s, scientists have been able to alter cells by inserting a foreign gene into cells’ DNA. That gene carries the genetic code for a protein — perhaps human insulin or a protein that makes plants resistant to pests — that the cells’ machinery will then produce.