(2cs) Build It up and Break It Down: Synthetic Biology and Biochemical Engineering for Sustainable Chemical Production and Bioremediation

The scale and severity of the environmental challenges the world faces—from environmental pollution to anthropogenic climate change—are daunting. Fortunately, nature has endowed us with a myriad of microscopic chemical factories that may be utilized in addressing these growing challenges. For example, bacteria can be engineered to produce a variety of value-added products, potentially supplanting fossil-based processes. Microbes also play a critical role in the remediation of environmental contaminants. My research group will work at the interface of biochemical engineering and synthetic biology to address these environmental challenges and will focus on three major topic areas:

• Carbon-neutral commodity chemical production using electromicrobial production

To avoid competition with agricultural land used for food production, next-generation bioprocesses should not be dependent on crop-derived sugars as feedstocks. One promising alternative to conventional bioprocesses is electromicrobial production (EMP), in which electricity or electrochemically generated mediator molecules serve as the microbial energy source to drive biochemical processes. The primary focus of my doctoral research, and a major component of my future research group, is engineering bacteria capable of converting electrochemically generated substrates to value-added products. In my doctoral research, I engineered strains of Cupriavidus necator (which can metabolize hydrogen gas or formic acid as energy sources) to possess novel functionalities for various applications, including simplified recovery of intracellular products and the production of the biofuels. Proof-of-principle studies using strains like C. necator for commodity chemical production have been established. However, for these systems to be feasible, the yield of the desired product must be high. A primary focus of my research group will be on developing strategies that improve the selectivity of product formation over the wasteful production of biomass, improving the economic and environmental feasibility of electromicrobial production.

• Synthetic biology for the bioremediation of emerging pollutants

Microbes already play an important role in the bioremediation of environmental pollutants. Due to the development of novel genetic toolkits, the prospect of engineering strains with augmented potential to remediate environmental contaminants is promising. The bulk of synthetic biology work in bacteria has relied on the use of a couple of select strains as microbial chassis (e.g., E. coli). However, these strains may not be well-suited for particular bioremediation efforts, such as remediation in harsh environments or the complete degradation of compounds requiring complex metabolic pathways. My research group will focus on developing synthetic biology techniques to engineer non-conventional bacterial strains capable of enhanced degradation of emerging environmental pollutants.

• Process modeling, technoeconomic assessment, and life cycle analysis of novel biochemical technologies

A major component of my doctoral work involved developing modeling and analytical frameworks for electromicrobial production systems by integrating biochemical reaction modeling with life cycle analysis (LCA) and techno-economic assessment (TEA). These frameworks provide a bridge between laboratory research and actual pilot-scale development. While the work in my doctoral studies revolved around a few select proposed EMP systems, I intend to expand this work to develop more generalizable frameworks to assess novel biochemical systems, particularly in carbon-neutral chemical production and bioremediation.

Ph.D. Dissertation: Microbial Engineering and Process Modeling Toward the Development of Electromicrobial Production Systems

Ph.D. Mentor: Douglas S. Clark, Department of Chemical and Biomolecular Engineering, University of California, Berkeley

Teaching Interests

As a graduate student, I served as a graduate student instructor (equivalent position to “teaching assistant” at other institutions) for four semesters. In this time, I received two awards from the Graduate Division of UC Berkeley, the Outstanding Graduate Student Instructor Award and the Teaching Effectiveness Award. I also received a Certificate of Teaching and Learning in Higher Education offered by the UC Berkeley Graduate Division. Through these experiences, I feel confident in teaching most of the core chemical engineering courses in the undergraduate curriculum. My research interests require a firm understanding of Chemical Kinetics/Chemical Reaction Engineering, Chemical Thermodynamics, and Process Design, and I therefore feel particularly comfortable in teaching these courses. I am also interested in teaching elective courses closer to my research focus, such as Biochemical Engineering or a closely related course. If these elective courses are not currently offered, I would be interested in developing such a course.

One of my long-term career goals is to introduce more interdisciplinary study into the chemical engineering curriculum. The intersection of science/engineering with social issues has been elevated in recent years, and an understanding of how social structures such as race, gender, and class impact scientific education, research, and industry will be essential for the success of future chemical engineers. However, current curricula are generally insufficient in conveying this knowledge to students in most STEM fields. Through the UC Berkeley College of Chemistry Graduate Diversity Program, I co-developed and co-taught a pilot course titled “Transformative pedagogy for chemical engineers.” In this graduate-level seminar course, students read texts from fields such as science and technology studies, the humanities, and social sciences, discussed how the concepts in these texts can be applied to our scientific institutions, and presented group projects on interventions that could be made to address some of the themes raised throughout the course. A long-term goal of mine is to transform this pilot seminar course into a full-length course that can be integrated into chemical engineering curricula at both the undergraduate and graduate level.