Background
Dr. Benjamin Keith Keitz and his team have developed a new controlled polymerization methodology using an electroactive bacterium to synthesize responsive materials. Dr. Keitz is an Assistant Professor in the Department of Chemical Engineering at UT Austin. His primary research area focuses on using chemical and biological synthesis techniques in combination with chemical engineering processes to design innovative functional materials. Dr. Keitz is the recipient of the NSF CAREER Award, the Air Force Office of Scientific Research Young Investigator Award, and the NIH Maximizing Investigator's Award. He has published various technical articles, and his research work has broad applicability in the fields of catalysis, energy generation, environmental remediation, biological separation, and the development of new medical procedures/medicines.
Invention
The developed controlled polymerization technique uses the electroactive bacterium Shewanella oneidensis (MR-1) as a “living electrode” in combination with an inorganic catalyst for the synthesis of well-defined polymers (e.g., polyolefin) or for the preparation of responsive materials which can change properties as a result of adjustments in specific biological and chemical inputs.
The developed system is composed of four components; S. oneidensis, a metal catalyst, a monomer, and an initiator. S. oneidensis reduces the metal catalyst, which in turn activates the initiator, which adds monomer units to form a polymer chain. The reaction rate is controlled by S. oneidensis and the structure/type of metal catalyst used in the reaction. The technology takes advantage of the electron transport capacity of the electroactive bacteria, where electrons generated during bacterial metabolism are used to reduce a metal catalyst and turn over/control a catalytic cycle.
Metabolic engineering practices take advantage of microorganisms' flexible nature and genetic tunability (e.g., E. coli) for use in fuel production, soft material manufacture, and pharmaceutical development. Transition metal (e.g., palladium) applications normally require elevated temperatures, pressures, and the use of organic solvents to catalyze biorthogonal labeling of proteins and metabolites. The developed technology combines both fields, metabolic engineering and transition metal catalysis, to create new routes to produce pharmaceuticals, fuels, and advanced materials.
Potential medical applications of the developed polymerization technique include tissue engineering, wound repair, and emerging bio-material/medical applications.
