Start
Feb 10, 2015 - 16:00
End
Feb 10, 2015 - 17:00
Venue
Room 240 Computer Lab Chemical Engineering
Event Type
Speaker
Dr. Aindrila Mukhopadhyay Director The Joint BioEnergy Institute (JBEI) U.S. Department of Energy Staff Scientist Physical Biosciences Division Lawrence Berkeley National Laboratory Emeryville CA USA.
Title
Engineering Solvent Tolerant Bacteria
Abstract: Many petrochemical compounds that are candidates for microbial production are also solvent-like in nature. Examples of such compounds are fuels and other bulk chemicals such as precursors for polymers and plastics. For these compounds two aspects impede the efficiency of microbial production. One is their inherent solvent like nature that results in toxicity towards the microbe. Second is product inhibition due to intracellular accumulation. We have used both systems and synthetic biology to successfully investigate the role of cellular transporters and other tolerance genes towards improving biofuel tolerance and production in Escherichia coli. Using simple but effective competition based strategies we identified heterologous pumps that bestowed tolerance against representative biogasoline biodiesel and biojetfuel candidates. We find functional genomics to be a useful approach to prospect for tolerance bestowing transporters and other genes and have used such candidates successfully to increase both tolerance and production levels. Transporters specifically stand out as an ideal tolerance mechanism as they also serve to export a final product. Building upon the discovery of various transport systems we are now exploring several avenues to optimize the use of transporters in microbial host engineering. Strategies that improve the efficiency of a transporter (e.g. via directed evolution) have allowed us to bypass the necessity to overexpress these high burden systems. Optimization of expression systems has also proven to be important in maximizing the fitness phenotypes in production strains.About the speaker: Dr. Mukhopadhyay received an MSc in Chemistry from the Indian Institute of Technology Bombay and has a PhD in Organic Chemistry from the University of Chicago. She is a Staff Scientist in the Physical Biosciences Division at the Lawrence Berkeley National Laboratory where she leads a multidisciplinary team to study stress response in bacteria using microbiological biochemical and systems biology tools. As part of JBEI’s Fuels Synthesis Division Dr. Mukhopadhyay is the Director of Host Engineering. Her projects include the study of two component signal transduction systems in the anaerobic sulfate reducing bacterium Desulfovibrio vulgaris Hildenborough and the study of a desert soil crust bacterium Microleus vaginatus. In the study of metabolically engineered microbes Dr Mukhopadhyay focuses on the role of efflux pumps as a mechanism to relieve toxicity from metabolite accumulation and increasing titer of metabolite production.