Rutgers University-led study has found that certain green algae are expected to better survive climate change compared to others due to genes they “stole” from bacteria.
The Picochlorum single-celled species of green algae, which evolved to tolerate hostile and fluctuating conditions in salt marshes and inland salt flats, suggest ways scientists may someday engineer more robust algae to serve as biofuels, said senior author Debashish Bhattacharya, distinguished professor in the Department of Biochemistry and Microbiology, at Rutgers.
“These photosynthetic species are tiny and have small genomes compared with humans, but they managed to survive in hostile conditions such as salt marshes and salt flats where light and salinity fluctuate widely as seasons change,” he said.
Understanding how microalgae adapt to rapidly changing environments can help clarify the potential impact of climate change on the biology at the base of the food chain, the researchers said. Next steps include developing robust Picochlorum species as biofuel feedstock and as targets for genetic engineering to produce bio-products.
These species have been studied for potential use in remediating wastewater, producing biomass and serving as feed in aquaculture, the study noted. Using genetic tools, scientists have already manipulated one species to increase lipid production.
The findings reveal how the miniaturized genomes of green algae have evolved from the larger genomes of their freshwater ancestors to become resilient primary producers of organic compounds that support ecosystems, Dr. Bhattacharya said.
This transition to a saltier and more hostile environment achieved by Picochlorum occurred over millions of years, but parallels what is happening on a more rapid scale now due to climate change, he explained.
Lead author Fatima Foflonker, who earned a doctorate from Rutgers’ School of Graduate Studies and is a post-doctoral researcher at Brookhaven National Laboratory, discovered that Picochlorum species of green algae stole genes from bacteria, allowing them to cope with salt and other physical stresses.