. At present, hydrogen in fuel cells is extracted from natural gas, a nonrenewable source. Scientists are researching how to use a kind of single-cell algae called Chlamydomonas reinhardtii as a renewable hydrogen source. Additional applications include using the Chlamydomonas chloroplast as a bioreactor to create a variety of novel proteins for agricultural, industrial, and biomedical purposes.

Biologists from the Boyce Thompson Institute (BTI) at Cornell University say the algae is already an important biological model for genetics research. BTI scientists recently sequenced the complete genome of the plant's chloroplast (the area of the plant that harvests light energy). According to David Stern, biologist and vice president of research at BTI, the group is also exploring how the algae responds to phosphates. "The developed world puts too much phosphorous fertilizer on plants and crops," he says. "Working with Chlamydomonas, we can quickly test ways to improve tolerance or adaptation, perhaps leading to ways of engineering crop plants for the same purpose," he adds. Reducing fertilizer might cut phosphorous runoffs into creeks, streams, and lakes. Phosphate leaching is a prime cause of algae blooms in lakes and ponds around agricultural areas.