Engineered bacteria can produce the sugars from carbon dioxide
Scientists from a university in Israel reported that they have engineered bacteria that can produce the sugars needed to make a cell from the greenhouse gas carbon dioxide (CO2).
Scientists from Weizmann Institute of Science “reprogrammed” an organism — that consumes sugar and releases CO2 — so that it can consume CO2 from the environment and produce sugar.
Lead researcher at the university Niv Antonovsky said that the ability to improve carbon fixation is crucial for our ability to cope with future challenges, such as the need to supply food to a growing population on shrinking land resources while using less fossil fuel.
Antonovsky, who performed the experiment at Ron Milo’s lab at the institute’s Plant and Environmental Sciences Department, attached the genes containing the information for building a metabolic pathway for carbon fixation into the bacterium’s genome.
Although the bacteria produced the functional carbon fixation enzymes, the process did not “deliver the goods” as the bacteria failed to use carbon dioxide for sugar synthesis, relying instead on an external supply of sugar.
“Of course, we were dealing with an organism that has evolved over millions of years to eat sugar, not carbon dioxide. So we turned to evolution to help us create the system we intended,” Antonovsky said in a statement released by Weizmann Institute of Science.
To find a solution to this problem, the team designed tanks called “chemostats”, in which they grew the bacteria, gradually nudging them into developing an appetite for carbon dioxide.
The changed conditions forced the bacteria to learn to use the more abundant material in their environment.
In three month’s time the bacteria started using CO2 to create a significant portion of their body mass, including all the sugars needed to make a cell.
The team envisions that in the future their insights might be applied to creating microorganisms that soak up atmospheric CO2 and convert it into stored energy or to achieving crops with carbon fixing pathways, resulting in higher yields and better adaption to feeding humanity.