In this project funded by the Macromolecular, Supramolecular and Nanochemistry Program of the Chemistry Division, Judit Puskas of the University of Akron will develop strategies to quantify the formation of natural rubber, a polyterpenoid, from isoprene and to characterize the microstructure of the polyisoprene formed. The idea of the project is to gain a fundamental understanding of the reversible equilibria involved in terpenoid biosynthesis and to optimize their production from isoprene, an abundant substrate than can be obtained from renewable resources. The approach is to monitor the kinetics of monomer conversion in the presence of selected enzyme cocktails using high resolution size exclusion chromatography, nuclear magnetic resonance spectroscopy, and in situ infrared and Raman spectroscopy techniques. The production of natural rubber from Guayule and Russian Dandelion will also be investigated following the same strategy. The exact structure and molar mass of the obtained isoprenoids will be determined using a variety of analytical techniques, and the data will be used to reconstruct the biosynthetic reaction pathway. The project will be performed in collaboration with Alain Deffieux, University of Bordeaux, France, and Manuel Rodriguez-Concepcion, Centre for Research on Agricultural Genomics (CRAG), Spain. The broader impacts involve developing infrastructure for research and education through establishing multilateral international collaborations as well as promoting teaching, training and learning of graduate students through this project and its international dimensions. The project will encourage students to think "green," finding ways to emulate natural chemical pathways and contributing to sustainable materials development for future generations.

Isoprene and terpenoids are produced by all living things: plants, microbes and animals. They have essential functions in life processes such as respiration, photosynthesis, the regulation of growth and development, and others. They are also used to make important elastic materials that are used in a range of industries, such as automotive, apparel, and medical equipment. This project will contribute to a better understanding of the biochemistry of terpenoids and lead to green processes to access these chemicals.

Project Report

Summary. Isoprenoids or terpenoids, one of the largest families of natural products, are derived from an enzyme-catalyzed polymerization of a common building bock, isopentenyl pyrophosphate (IPP). Further enzymatic reactions and/or incorporation of functional groups eventually result in the production of many compounds essential to life such as vitamin A, steroids and colesterol, and important natural polymers (polyisoprenoids) such as natural rubber (NR). Although a number of isoprenoids exhibit extremely interesting properties, their direct recovery is limited due to their low concentration in natural sources, except for NR produced from Hevea brasiliensis or the Brazilian rubber tree. This international (France, Spain, USA) collaborative project aimed to develop alternative approaches toward the production of polyisoprenoids using a reversed enzymatic biosynthesis approach. Merit. The basic idea of the project was to get a fundamental understanding of the reversible equilibria involved in terpenoid biosynthesis. The ultimate goal is to construct microbial cell factories for the biosynthesis of polyisoprenoids starting from inexpensive renewable materials and by using genetically engineered enzymes and recombinant microorganisms. The collaboration between polymer chemists (Bordeaux, Akron) and isoprenoid bioengineering specialists (Barcelona) brought the necessary expertise for achieving the proposed goals. Our part focused on the analysis of rubber from three species: Hevea brasiliensis, Parthenium argentatum (guayule) and Ficus elastica. We developed a new method to monitor the growth of rubber in vitro (in a test tube) without the use of radioactive IPP building block, which is the currently accepted technique. We discovered that certain additives increased rubber production in the laboratory. We conducted field experiments in Brazil at a Hevea plantation. The results are still being analyzed and will show us if rubber production can be boosted using these additives. We also synthesized an artificial initiator that we plan to test in vitro. Broader Impacts. This project was interdisciplinary, involving biology, biochemistry, polymer chemistry, analytical chemistry and reaction engineering. It was built on established and new academic collaborators from the USA, France and Spain, and enjoyed support from the US Department of Agriculture (USDA), and the Department of Horticulture and Crop Science of Ohio State University, vital partners for success in such an interdisciplinary proposal. "Green" chemistry in general is very attractive, helping us to conserve our environment and to leave a better place for our children. The project supported post-doctoral fellows and students, including a visiting student from Brazil. The project exposed students to the great variety of scientific disciplines listed above. They have also had a chance to carry out part of their research at the USDA in France. Exposure to different cultures, organizations and work ethics prepares the students to work better in the global economy, making them more attractive to potential employers. Their horizons were broadened through the recently initiated new program connecting science and art, performed in collaboration with the Myers School of Art at The University of Akron. Outreach involved K-12 teachers and their students via the Akron Global Polymer Academy; its former Assistant Director, Dr. Carin Helfer, is still closely associated with our group. The project also contributed to the new text book "Puskas, J.E. Introduction to Polymer Chemistry: A Biobased Approach. ISBN: 978-1-60595-030-3. DEStech Publications Inc. 2014. 334 pages.

Agency
National Science Foundation (NSF)
Institute
Division of Chemistry (CHE)
Application #
1057954
Program Officer
Timothy Patten
Project Start
Project End
Budget Start
2010-09-15
Budget End
2014-08-31
Support Year
Fiscal Year
2010
Total Cost
$315,000
Indirect Cost
Name
University of Akron
Department
Type
DUNS #
City
Akron
State
OH
Country
United States
Zip Code
44325