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Mary Franden

Researcher IV-Molecular Biology

Mary.Ann.Franden@nrel.gov | 303-384-7767

Research Interests

Mary Ann Franden is a senior scientist in the Applied Biology Group of the National Bioenergy Center (NBC) at the National Renewable Energy Laboratory (NREL). Her current research focuses on metabolic engineering of organisms (bacteria and yeast) to include novel pathways for the production of a variety of advanced fuels and chemicals from lignocellulosic materials. She was also involved in the development of growth assay and fermentation tools to monitor the toxicity of Zymomonas by model compounds and hydrolysates. The identification of the dominant inhibitors present in lignocellulosic hydrolysates subsequently led to efforts for their mitigation during the pretreatment process. Franden also collaborated with DuPont on the Integrated Corn-Based Biorefinery cooperative research and development agreement (CRADA) toward the development of a proprietary ethanologen based on Zymomonas mobilis to convert sugars contained in the feedstock into high yields of ethanol with fewer byproducts. She has also collaborated with the Corn Refiners Association through a CRADA to identify suitable L-arabinose transporters for cloning to enhance arabinose uptake.

  • Biological upgrading of sugars to biofuels

  • Upgrading of lignin to advanced biofuels and chemicals

  • Metabolic engineering of bacteria and yeast

  • Hydrolysate toxicity

  • Fermentation

  • Sugar transport in yeast and Zymomonas

  • Metabolite analysis

  • Protein overexpression and purification


Education

  • Post-Baccalaureate Status, Emphasis on Computer Science, University of Houston and University of Colorado at Denver

  • B.S., Microbiology, Ohio State University


Professional Experience

  • Senior Scientist, NREL, NBC, Applied Biology Group

  • Professional Research Assistant, University of Colorado Health Sciences Center, Division of Endocrinology

  • Associate Molecular Biologist, NREL, Applied Biological Sciences Branch, Alternative Fuels Division

  • Professional Research Assistant, University of Colorado Health Sciences Center, Department of Biochemistry, Biophysics, and Genetics3


Patents

  1. "Biotcatalysts with enhanced inhibitor tolerance," U.S. Patent Application No. 20140342421 (2014)

  2. "L-arabinose fermenting yeast," U.S. Patent No. 8,841,090 (2014)

  3. "Zymomonas with improved xylose utilization in stress conditions," U.S. Patent No. 8,465,961 (2013)

  4. "L-arabinose fermenting yeast," U.S. Patent No. 8,372,626 (2013)

  5. "Zymomonas with improved xylose utilization in stress conditions," U.S. Patent No. 8,247,208 (2012)

  6. "Zymomonas with improved ethanol production in medium containing concentrated sugars and acetate," E.P. Patent No. 2209899 B1 (2012)

  7. "Zymomonas with improved xylose utilization in stress conditions for the production of ethanol," E.P. Patent No. 2376623 A1 (2011)

  8. "Zymomonas with improved xylose utilization," U.S. Patent No. 7,998,722 (2011)

  9. "High expression Zymomonas promoters" U.S. Patent No. 7,989,206 (2011)

  10. "Process for the production of ethanol in a medium comprising xylose employing a recombinant Zymomonas strain with reduced HIMA expression," E.P. Patent No. 2205753 B1 (2011)

  11. "Zymomonas with improved ethanol production in medium containing concentrated sugars and acetate," U.S. Patent No. 7,897,396 (2011)

  12. "Zymomonas with improved ethanol production in medium containing concentrated sugars and acetate," U.S. Patent No. 7,803,623 (2010)

  13. "L-arabinose fermenting yeast," U.S. Patent No. 7,846,712 (2010)

  14. "Ethanol production in fermentation of mixed sugars containing xylose," U.S. Patent No. 7,629,156 (2009)

  15. "Recombinant Lactobacillus for fermentation of xylose to lactic acid and lactate," U.S. Patent No. 5,798,237 (1998)


Featured Publications

  1. "Adipic Acid Production from Lignin," Energy and Environmental Science (2015)

  2. "Novel Transporters from Kluyveromyces marxianus and Pichia guilliermondii Expressed in Saccharomyces cerevisiae Enable Growth on L-arabinose and D-xylose," Yeast (2015)

  3. "Insights into Acetate Toxicity in Zymomonas mobilis 8b Using Different Substrates," Biotechnology for Biofuels (2014)

  4. "Lignin Valorization through Integrated Biological Funneling and Chemical Catalysis," Proceedings of the National Academy of Sciences of the United States of America (2014)

  5. "Inhibition of Growth of Zymomonas mobilis by Model Compounds Found in Lignocellulosic Hydrolsyates," Biotechnology for Biofuels (2013)

  6. "The Impacts of Deacetylation Prior to Dilute Acid Pretreatment on the Bioethanol Process," Biotechnology for Biofuels (2012)

  7. "Development of a High-Throughput Method to Evaluate the Impact of Inhibitory Compounds from Lignocellulosic Hydrolysates on the Growth of Zymomonas mobilis," Journal of Biotechnology (2009)

  8. "Utilization and Transport of L-arabinose by Non-Saccharomyces Yeasts," Cellulose (2009)

  9. "D-Xylose transport by Candida succiphila and Kluyveromyces marxianus," Applied Biochemistry and Biotechnology (2003)

  10. "Promising Ethanologens for Xylose Fermentation," Applied Biochemistry and Biotechnology (1995)

View all NREL Publications for Mary Ann Franden.