Scientists have been tweaking algae in the lab for use in everything from making foam to making fuel to using it to clean up wastewater. But till now, at least in the US, those tests have been confined to the lab. The US Environmental Protection Agency approved moving things outdoors, and green glowing algae was let loose in water from five reservoirs in California. Should anyone be worried? Not all, according to the results.
For starters, the algae used was harmless. The engineered species is known as Acutodesmus dimorphus, and it was designed to synthesize fatty acids and undergo green fluorescent protein expression. It was also designed to be safe.
"The genes we put in were specifically chosen to be benign, so they could not harm the environment, as this was the world's first outdoor genetically engineered algae trial," Stephen Mayfield told us. Mayfield is the director of the California Center for Algae Biotechnology at the University of California San Diego and co-author on a paper about the trial in the journal Algal Research. "In the future we will put in genes that increase biomass accumulation, or improve lipid content and quality."
Also, the algae wasn't released into lakes in the wild, but rather, water from five different reservoirs in the UC San Diego area was taken back to the center and placed in different plastic ponds. The engineered algae was then added to those ponds along with a non-modified "wild-type" algae. The algae was cultivated in the ponds for 50 days and water samples were then analyzed.
The study concluded that the genetically engineered (GE) algae had the same impact on the pond water as the natural algae in terms of its effect on "biodiversity, species composition, and biomass of native algae," according to the paper. It was also concluded that neither the GE algae nor the wild-type algae could "outcompete" the native strains of algae naturally present in the water.
As to the importance of growing algae outside the lab, Mayfield told us that it's a matter of scale.
"For algae to be able to compete with fossil fuels and other forms of industrial agriculture, we are going to need to grow them outside in really large ponds, as only with this economy of scale can we produce commodity products, like foods, feeds and fuels that the world needs," he said. "So this experiment was designed to identify how engineered traits performed in this real-world outdoor setting."
Or, as study lead author Shawn Szyjka put it in a press release: "Progress made in the lab means little if you can't reproduce the phenotype in a production setting."
The next step for the researchers is to test out algae that has had different sets of genes altered, and to extend the trial over several months to examine how seasonality, weather and other environmental factors impact the system.
Source: UC San Diego