MARIA GHIRARDI, Research Associate Professor
Environmental Science & Engineering
Colorado School of Mines
Coolbaugh Hall
Golden, CO 80401-1887

Senior Scientist
Basic Sciences Center
National Renewable Energy Laboratory
1617 Cole Blvd.
Golden, CO 80401
www.nrel.gov/basic_sciences/basicframe.html

Phone:303-384-6312 Fax: 303-384-6150 Email: maria_ghirardi@nrel.gov

Education

• Ph.D. Comparative Biochemistry, University of California, Berkley, 1998
• M. A. Comparative Biochemistry, University of California, Berkley, 1983
• B.S. Bioenergetics, University of California, Berkley, 1981

Work Experience

• Research Associate Professor (2000-present), Colorado School of Mines
• Senior Scientist (1997-present), National Renewable Energy Laboratory
• Scientist (1995-1997), National Renewable Energy Laboratory Research Associate (1991-1995), National Renewable Energy Laboratory Scientific Consultant (1991), Martek Inc., Columbia MD
• Research Associate (1988-1991), USDA, Beltsville, MD
• Research Associate (1987-1988), Dow Chemicals, Walnut Creek, CA
• Research Assistant (1981-1988), University of California, Berkeley, CA
• Teaching Assistant (1983-1984), University of California, Berkeley, CA

Research Interests

Algal Hydrogen Production

Green algae can produce hydrogen gas, H2, in a process called "biophotolysis" or "photobiological hydrogen production." This process is carried out by photosynthetic enzymes, which split water to obtain electrons, excite these electrons with photons, and eventually use these electrons to reduce 2H⁺ to H2. The scientific challenge associated with this approach to hydrogen production is that the enzyme that actually releases the hydrogen, called a "reversible hydrogenase", is sensitive to oxygen. The process of photosynthesis, of course, produces oxygen and this normally stops hydrogen production very quickly in green algae. So, to overcome this problem, we are generating O2-tolerant, H2-producing mutants of the green alga Chlamydomonas reinhardtii by various genetic approaches. The ultimate goal of this work is to develop a water-splitting process that will result in a commercial H2-producing system that is cost effective, scalable to large production, non-polluting, and self-sustaining.

Selected Publications and Presentations

Ghirardi, M.L., T.W. Lutton and M. Seibert. 1995. Selective effect of carboxyl and histidyl modifiers on binding and single turnover photooxidation of Mn²⁺ by Photosystem II. In: Photosynthesis: from Light to Biosphere (P. Mathis, ed.), Kluwer Academic Publishers, The Netherlands, vol. II, 409-412.

Ghirardi, M.L., T.W. Lutton and M. Seibert. 1996. Interactions between diphenylcarbazide, zinc, cobalt, and manganese on the oxidizing side of Photosystem II. Biochem. 35, 1820-1828.

Ghirardi, M.L., R.K. Togasaki and M. Seibert. 1997. Oxygen sensitivity of algal H2-production. Appl. Biochem. Biotechnol. 63-65, 141-151.

Seibert, M., M. Ghirardi, P.C. Maness and P. Weaver. 1997. Photobiological production of renewable fuels, chemicals, and materials. In: Proceedings of the International AAA BIOTEC Conference (Ferrara, Italy; Oct. 1996), Vol. IV, pp. 122-136.

Ghirardi, M.L., T.W. Lutton and M. Seibert. 1998. Effect of carboxyl amino acid modification on the properties of the high-affinity, Mn-binding sites in Photosystem II. Biochem 37, 13559-13566.

Ghirardi, M.L., C. Preston and M. Seibert. 1998. Use of a novel histidyl-modifier to probe for residues on tris-treated Photosystem II membranes that may bind functional manganese. Biochem 37, 13567-13574.

Seibert, M., T. Flynn, D. Benson, E. Tracy and M. Ghirardi. 1998. Development of selection/screening procedures for rapid identification of H2-producing algal mutants with increased O2-tolerance. In: Biohydrogen (O.R. Zaborsky, ed.; J.R. Benemann, T. Matsunaga, J. Miyake, and A. San Pietro, associate eds.), Plenum Publishing Corporation, New York, N.Y., pp. 227-234.

Ghirardi, M.L., T. Flynn, M. Forestier, A. Iyer, A. Melis, P. Danielson and M. Seibert. 1999. Generation of C. reinhardtii mutants that photoproduce H2 from H2O in the presence of O2. In : Photosynthesis: Mechanisms and Effects, (G. Garab, ed.), Kluwer Academic Publishers, The Netherlands, vol.III, pp. 1959-1962.

Melis, A., L. Zhang, M. Forestier, M.L. Ghirardi and M. Seibert. 2000. Sustained photobiological hydrogen gas production upon reversible inactivation of oxygen evolution in the green alga Chlamydomonas reinhardtii.Plant Physiol. 122, 127-136.

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Last Updated: October 9, 2001