Green Design

Genetically Engineering Algae for Biodiesel

John Morgan, an associate professor of chemical engineering at Purdue University, is leading a portion of a federally funded effort based at Iowa State University aimed at creating genetically engineered algae for biodiesel production.

Currently, hydrocarbon fuels such as diesel and gasoline require complex chemical processing to be manufactured and are made primarily from non-renewable fossil fuels, which are being depleted, whereas single-cell algae use photosynthesis and are renewable resources.

The Purdue portion of the work focuses on creating algae that produce more lipids, the precursor of biofuels. The algae harness solar energy to make lipids from carbon dioxide in the atmosphere.

"Algae now store some of their carbon as lipids, but not enough to be useful in producing biodiesel," Morgan said. "We need to genetically engineer them to increase the amount of lipids they accumulate."


The three-year project is funded with a grant of more than $4 million from the DOE, with about $1 million going to Purdue's portion of the research.

The algae are being grown in a "bioreactor" in Morgan's laboratory in the Forney Hall of Chemical Engineering. Algae carry out photosynthesis using energy from light to convert carbon dioxide into a variety of products, including lipids.

"The carbon dioxide is routed in many directions to produce various products, and we are trying to maximize traffic in the specific pathway that leads to lipid storage," Morgan said. "We want to maximize the accumulation of lipids, which can then be harvested and turned into biodiesel."

The Purdue group will create "flux maps" that reveal the speed of reactions along many "metabolic pathways" inside algae, information that should enable researchers to engineer algae to store more lipids.

Other researchers in the project will focus on creating algae that thrive in higher temperatures than natural algae can tolerate. The elevated temperature kills contaminants that hinder algae growth. Another facet of the work will focus on increasing "carbon dioxide assimilation," the first of many steps leading to lipid storage.

(Purdue University)