Israeli scientists transform a gut bacteria to ally with CO2

Israeli scientist Ron Milo is 44 years old and an ambitious project at the helm: to sustainably produce food, generate renewable fuels and eliminate CO2 from the atmosphere to curb climate change. He wants to get it all at once. And his team just made a leap towards that triple goal. Researchers at the Weizmann Institute of Science in Rejovot, Israel, have manipulated a bacterium so that instead of consuming sugar, it absorbs CO2, the main gas responsible for global warming. It's the first time that a microbe's growth mode has been transformed,

Bacteria E. coli in

normal conditions

The bacterium Escherichia coli (E. coli) is a heterotroph organism, unable to make its own organic matter from inorganic substances.

Sugar

E. coli Bacterium

CO2

Energy

and stuff

organic

From sugar, the bacteria generates energy and organic matter and expels CO2.

Modifications

Engineering

genetics

Targeted evolution

in the lab,

in an atmosphere

high CO2

, little sugars

Modified E. coli Bacteria

Modified E. coli is an autotrophean organism, capable of making its own organic matter from inorganic substances, as plants do

.

formiatosmolecules

(chemical energy)

CO2

CO2

Cycle

fixing

carbon

Matter

organic

It was achieved that from energy and CO2, without sugar, the bacteria generated organic matter, but continues to expel CO2.

Future job

StheE tibacy

on an industrial scale

From renewable energy and CO2 the bacteria will generate organic matter (proteins intended to feed livestock) and other by-products such as ethanol and butanol, useful for making fuels.

Renewable energy

CO2

Cycle

fixing

carbon

Matter

organic

Food and

green fuels

Source: Gleizer et al.

COUNTRY

Bacteria E. coli under normal conditions

The bacterium Escherichia coli (E. coli) is a heterotroph organism, unable to make its own organic matter from inorganic substances.

Sugar

E. coli Bacterium

CO2

Energy

and stuff

organic

From sugar, the bacteria generates energy and organic matter and expels CO2.

Modifications

Engineering

genetics

Targeted evolution

in the lab,

in an atmosphere

high CO2

, little sugars

Modified E. coli Bacteria

Modified E. coli is an autotrophean organism, capable of making its own organic matter from inorganic substances, as plants do

.

formiatosmolecules

(chemical energy)

CO2

CO2

Cycle

fixing

carbon

Matter

organic

It was achieved that from energy and CO2, without sugar, the bacteria generated organic matter, but continues to expel CO2.

Future job

Future E. coli bacteria on an industrial scale

From renewable energy and CO2 the bacteria will generate organic matter (proteins intended to feed livestock) and other by-products such as ethanol and butanol, useful for making fuels.

Renewable energy

CO2

Cycle

fixing

carbon

Matter

organic

Food and

green fuels

Source: Gleizer et al.

COUNTRY

Bacteria E. coli under normal conditions

The bacterium Escherichia coli (E. coli) is a heterotroph organism, unable to make its own organic matter from inorganic substances.

Sugar

E. coli Bacterium

CO2

Energy

and stuff

organic

From sugar, the bacteria generates energy and organic matter and expels CO2.

Modifications

Engineering

genetics

Targeted evolution

in the lab,

in an atmosphere

high CO2

, little sugars

Modified E. coli Bacteria

Modified E. coli is an autotrophean organism, capable of making its own organic matter from inorganic substances, as plants do

.

formiatosmolecules

(chemical energy)

CO2

CO2

Cycle

fixing

carbon

Matter

organic

It was achieved that from energy and CO2, without sugar, the bacteria generated organic matter, but continues to expel CO2.

Future job

Future E. coli bacteria on an industrial scale

From renewable energy and CO2 the bacteria will generate organic matter (proteins intended to feed livestock) and other by-products such as ethanol and butanol, useful for making fuels.

formiatosmolecules

(chemical energy)

CO2

Cycle

fixing

carbon

Matter

organic

Food and

green fuels

Source: Gleizer et al.

COUNTRY

"We believe that this progress could pave the way for industrial production of food and renewable fuels," milo explains. His group has used a common bacterium in the human gut, Escherichia coli. Under normal conditions, the microbe feeds on sugars and converts them into energy and proteins, emitting CO2 in the process. Milo's team has used sophisticated genetic engineering to ensure that the bacteria does not use sugars, but CO2 and chemical energy (molecules called formiatos

).

"In the future, we may be able to use renewable energy to boost CO2fixation and protein production in these bacteria," says Milo. Their plan is to continue to modify microbes so that, in addition to absorbing CO2, they produce proteins that can be used to feed livestock and fuels such as ethanol and butanol.

"It's not the end of the road, but this is a very important step," claps microbiologist Victor de Lorenzo

"By producing zero net emissionfuels in industrial environments, we could reduce fossil fuel consumption and thus reduce global CO2 emissions," Milo reflects. "Bacteria would not be able to survive in the wild, as they would not have the necessary energy sources and would be displaced by more suitable natural bacteria. We don't want to interfere in natural ecology in any way," says the Israeli scientist, who has led the work with his colleague Shmuel Gleizer.

Milo's team recognizes an important Achilles heel. Researchers have managed to get the bacteria to fix CO2, but that process requires energy and the energy sources used—formiates—in turn become CO2. The bacteria actually "produces more CO2 than you consume," Milo admits. In the future, however, industrially used formicates could be produced from renewable and CO2 atmospheric electricity. "In that scenario, bacteria would be net CO2 fixators of the atmosphere rather than broadcasters," the scientist reasons, the results of which are published today in the prestigious journal Cell.

Milo remembers that living beings can be divided into autotrophs and heterotrophs. The former, such as green plants, can convert CO2 into biological materials. Seconds, such as animals and the bacteria Escherichia coli, need organic compounds. Scientists at the Weizmann Institute have first transformed a heterotroph into an autotroph.

"It is not the end of the road, but this is a very important step", applauds the microbiologist Víctor de Lorenzo, from the National Center for Biotechnology, in Madrid. The researcher, who has not participated in this study, argues that "a piece of DNA could be designed in the laboratory with all the information necessary for bacteria to incorporate it and fix CO2". A controversial option, he says, would be to make a political decision to spread this "genetic device" by nature, in order to reduce CO2 atmospheric. At the moment, that possibility is science fiction, but it won't be for long,