Genetically engineered algae can be successfully cultivated outdoors while maintaining new traits — all without adversely affecting native algae populations, scientists at UC San Diego and San Diego-based Sapphire Energy reported Thursday.
Their study was the first outdoor field trial sanctioned by the U.S. Environmental Protection Agency for genetically engineered algae, a potential future source of fuel and increased food supplies. The U.S. Department of Energy funded the study, which was published in the journal Algal Research.
"Just as agricultural experts for decades have used targeted genetic engineering to produce robust food crops that provide human food security, this study is the first step to demonstrate that we can do the same with genetically engineered algae," said Stephen Mayfield, a UCSD professor of biology and an algae geneticist.
"Algae biomass can address many needs that are key to a sustainable future," said Mayfield, also director of the California Center for Algae Biotechnology and the Food and Fuel for the 21st Century initiative.
"This is the first of many studies testing this technology in field settings," he said.
In the 50-day experiment, scientists cultured genetically engineered and nonengineered strains of the algae species Acutodesmus dimorphus side-by-side.
Testing both algae strains in water samples taken from five regional lakes showed similar levels of growth in the tests and that the genetic modification did not change the impact of the cultivated strains on native algae communities, the researchers said.
The genetically engineered strain had genes for biosynthesis of fatty acids — useful for energy storage — and green fluorescent protein expression, which can be used to make biosensors.
"This study showed the framework for how this type of testing can be done in the future," said study co-author Jonathan Shurin, an ecologist in UCSD's Division of Biological Sciences.
"If we are going to maintain our standard of living in the future we are going to need sustainable food and energy, and ways of making those that do not disrupt the environment," Shurin said. "Molecular biology and biotechnology are powerful tools to help us achieve that. Our experiment was a first step towards an evidence-based evaluation of genetically engineered algae and their benefits and environmental risks."
The scientists said that future testing will include additional gene types in experiments that run several months, allowing the researchers to further evaluate influences from weather, seasonal shifts and other environmental factors.
