Tuesday, July 31, 2007 - 2:00 PM
S109
Algal Biohydrogen Production
Michael Seibert, Chemical and Biosciences Center, National Renewable Energy Laboratory, 1617 Cole Blvd., Golden, CO 80401
The green alga, Chlamydomonas reinhardtii, can directly couple light-driven photosynthetic water oxidation to [FeFe]-hydrogenase-linked H2 production. We have examined the process under sulfate-nutrient-stress conditions and have found ways to produce H2 continuously for up to 6 months. Nevertheless, efficiencies are low and a number of issues are being addressed, including the sensitivity of the hydrogenase enzyme to O2. Molecular Dynamics modeling has been used along with site-directed mutagenesis to restrict access of O2 to the catalytic site. However, a better understanding of the factors that promote H2 production in algae is also being sought by “omics” methods. Significant changes in the transcript levels of many genes associated with algal metabolism, and particularly fermentation, occur when H2 is produced. More detailed knowledge of the metabolic and regulatory context that facilitates H2 production will be necessary to understand and also ultimately eliminate current limitations in yields.
Web Page: www.nrel.gov/research_fellows/seibert.html