A key part of blue-green algae could help engineer crops like wheat, rice and soybean to capture more carbon dioxide from the atmosphere and tackle the climate crisis.
University of Newcastle research, published in Science Advances, discovered how an enzyme in the algae boosts the extraction of CO2.
The algae is normally known for causing toxic blooms in lakes and rivers that pose a threat to wildlife and humans.
But it's now been described as "tiny carbon superheroes".
Dr Ben Long said the study focused on unravelling a mystery about how the enzyme "gobbled" such a high concentration of CO2.
"What we found was completely unexpected," he said.
They discovered a "switch" crucial to the enzyme being able to sequester CO2 efficiently.
Blue-green algae, also known as cyanobacteria, are "responsible for about 13 per cent of the global carbon dioxide captured every year".
"They're mostly in the oceans, which is surprising," Dr Long said.
He said organisms floating in the ocean capture about "50 per cent of global CO2 production every year".
"Plants do the other 50 per cent on land."
Also, Dr Long highlighted that he prefers the term cyanobacteria because "it's not actually algae, it's photosynthetic bacteria".
The study's lead author and PhD researcher Sacha Pulsford said cyanobacteria had a "carbon dioxide concentrating mechanism".
Ms Pulsford, of Australian National University, said this allowed them to turn carbon into sugars "at a significantly faster rate than standard plants and crop species".
Dr Long said some crops already have a CO2 "concentrating mechanism".
"But it's not as good as the cyanobacterial one."
Dr Long said his team's research was "focused on trying to make plants capture CO2 more efficiently".
"They wouldn't need as much nitrogen fertiliser and water and we could improve crop yield."
This would help make global food systems more resilient to climate change.
"We're trying to engineer the way that cyanobacteria capture carbon dioxide into plant cells," Dr Long said.
"When they capture more carbon dioxide, they generate more food for us to eat. We'd expect yield increases of 8 per cent to 30 per cent."
Dr Long, a synthetic biologist, said there were "limitations to which plants we can engineer".
"We want to aim this at crops like rice, soybean and wheat. They're plants we know could benefit from this approach."
The system could also be "put into trees", depositing extra carbon into timber and boosting carbon sinks.
As such, he said cyanobacteria could be used to tackle climate change.
Dr Long said Ms Pulsford did most of the work needed for the published study "as an honour's student during COVID".
"She finalised it all leading into her PhD. It's a remarkable piece of work from someone so young."
