Lori Maggio-Hall, senior research microbiologist at DuPont Central Research and Development delivered the talk, “Metabolic Engineering of E. coli for the Commercial Production of 1,3-propanediol,” at the Virginia Bioinformatics Institute (VBI) on Tuesday, June 15. Maggio-Hall was a special guest lecturer for the Research Experiences for Undergraduates (REU) Site: Microbiology in the Post Genome Era, which is led by VBI Associate Professor Biswarup Mukhopadhyay.
Maggio-Hall discussed DuPont’s successful development and
commercial-scale implementation of a bioprocess to convert corn sugar to
1,3-propanediol (BioPDO). This project serves as a perfect example of
team science in action, involving approximately 50 scientists with
expertise in microbiology, biochemistry, mathematics, and engineering.
DuPont’s goal was to develop a new type of polyester with vastly
superior properties. The polyester, commercialized under the name
Sorona®, is now widely available in Mohawk® carpeting. The BioPDO
monomer is also used in a number of commercial products, from
biodegradable airplane deicers to shampoo. DuPont won a 2003
Presidential Green Chemistry Challenge Award for their development of
the fermentation process for production of 1,3-propanediol from
corn-derived glucose in recombinant Escherichia coli K-12. According to
Maggio-Hall, DuPont began production of the polymer in 2006.
Maggio-Hall’s key take away messages were:
• Economic analysis dictates selection of biological targets and
• Reaching the production phase was a long process because a low-cost
chemical production method could not be identified, which led to the
decision to use a bioprocess
• Focus during the development process was on rate (speed of the
chemical reaction), titer (measure of concentration), and yield (the
amount of product obtained)
Researchers working on this project introduced genes encoding a BioPDO
pathway into E. coli to construct the biocatalyst. Multiple metabolic
engineering approaches were used to optimize the BioPDO pathway and to
modify the host’s native metabolism to maximize carbon flux from glucose
into the product pathway. Maggio-Hall explained how both yield and
titer played very important roles in developing 1,3-propanediol in an
economically feasible way.
According to Maggio-Hall, “What we wanted to do was make less of
everything else that was produced during the process and more of our
Maggio-Hall met with REU and graduate students, as well as faculty
members, and shared her experiences from her journey as an undergraduate
at the University of Illinois at Urbana-Champaign, to her Ph.D. and
postdoctoral work at the University of Wisconsin, to her current
position at DuPont. REU Site: Microbiology in the Post Genome Era is
supported by the National Science Foundation (NSF), Virginia Tech’s
Fralin Life Science Institute, and VBI.
June 17, 2010