Biotechnology Program Division of Chemical, Bioengineering, Environmental, and Transport Systems
Eliciting Novel Microbial Phenotypes through Transcriptional, Degradation, and Translational Engineering
Gregory Stephanopoulos Massachusetts Institute of Technology CBET-0730238
The goal of this research is to select members of the transcription and translation machinery in order to enrich the repertoire of global regulators by which new, otherwise unreachable, phenotypes can be elicited in prokaryotic cells. Methods to quantify the diversity of libraries resulting from the engineering of various regulators and their combinations will be developed as means of guiding the phenotype improvement process to the most promising candidate regulators. Finally, a series of specially designed experiments will elucidate the mechanism by which mutant regulators interact with the native machinery of the host cell in eliciting the new phenotypes.
The intellectual merit of this research lies in advancing the fundamental understanding of the transcription mechanism and its interaction with mutant regulators of global intracellular reach. Additionally, it will elucidate transcriptional regulation by identifying direct and indirect molecular interactions by which gene expression is affected. Perhaps the most lasting impact will be the realization that many cellular phenotypes are the collective property of many genes and, as such, should be optimized by more creative methods than single gene modulation, like global regulator engineering proposed herein.
The broader impact of the research is the opening of a new, totally unexplored, avenue to phenotype elicitation and strain improvement. This is of particular importance when one considers the specific phenotypes of tolerance to toxic compounds. As a model system, tolerance of E. coli to ethanol and other toxic byproducts of biomass hydrolysis will be studied. By engineering more tolerant strains, an overall biomass-to-biofuels conversion process will be substantially improved. Other biotechnological processes presently impaired from limited tolerances could similarly benefit from this research.
