Researchers in Israel modified a bacteria, which usually thrives on sugar, to consume carbon dioxide. The bacteria could be used to help manufacture long-term supplies of food and fuel, according to the scientists behind this alteration.
In a research that lasted several months, researchers created an E.coli strain able to consume CO2 for energy rather than organic elements, through genetic alteration. The scientists used the method known as ‘metabolic rewiring’ to help recreate the bacteria’s diet to make it absorb CO2 in a similar way to a plant. This required adding genes that assimilate CO2 and removing genes that normally consume sugar compounds.
“From a basic scientific perspective, we wanted to see if such a major transformation in the diet of bacteria – from dependence on sugar to the synthesis of all their biomass from CO2 – is possible,” said first author Shmuel Gleizer, a Weizmann Institute of Science postdoctoral researcher.
“Beyond testing the feasibility of such a transformation in the lab, we wanted to know how extreme an adaptation is needed in terms of the changes to the bacterial DNA blueprint.”
The team said the outcome is an impressive step forward in synthetic biology and showcase the plasticity of bacterial metabolism. This achievement could provide a context for future carbon-neutral bioproduction.
Transforming Compound Into Food and Fuel
According to senior author Ron Milo, a systems biologist at the Weizmann Institute of Science, the aim of the team was to create a suitable scientific platform that could improve CO2 fixation. This, in turn, could help solve issues related to the sustainable production of fuel and food, as well as global warming caused by CO2 emissions.
Dr. Gleizer said there was no available model for the process, and that the research shows, for the first time, a fruitful alteration of an E.coli mode of growth.
“When we started the directed evolutionary process, we had no clue as to our chances of success, and there were no precedents in the literature to guide or suggest the feasibility of such an extreme transformation. In addition, seeing, in the end, the relatively small number of genetic changes required to make this transition was surprising,” he said.
The authors of the study explained that a significant limitation is that the bacteria releases more CO2 than is absorbed via carbon fixation at the moment. Moreover, more observation and analysis is required before it is possible to take into consideration the adaptability of the accomplishment for industrial use.
The team says their next move will be to target the supply energy via renewable electricity to solve the issue of carbon dioxide release and enhance their comprehending of the conditions in which the E.coli can survive.
Professor Milo said that this attempt is a powerful proof of concept that leads to new interesting ways of using engineered bacteria to produce content we consider as waste into fuel, food, or other compounds that interest the world.
“It can also serve as a platform to better understand and improve the molecular machines that are the basis of food production for humanity and thus help in the future to increase yields in agriculture,” he added.
The research was published in the journal Cell.