Exploring the Relationships between Gene Regulation and Microbial Ecology for the Sustainable Production of Microalgae-base Biofuels

Yale University, New Haven CT

Investigators

Abstract

CBET-0854322 Jordan Widespread adoption of alternative liquid biofuels has the potential to mitigate CO2-caused climate change, boost local and national economies, and increase national security. Using microalgae-derived lipids as biofuel feed-stocks has documented advantages in production rate, land use, and CO2 sequestration over the more developed liquid biofuel alternatives, including ethanol and plant oils. The efficient application of this technology requires the incorporation of core bioprocess engineering concepts, including gene regulation and microbial ecology, into microalgae-based biofuel reactor design. The goal of this proposed research is to link gene regulation with microalgae function to design and produce robust mixed consortia microalgae reactors that maximize volumetric lipid content. Specific objectives include the following: (i) sequence genes involved in microalgae lipid production and build gene expression microarrays, (ii) determine the effects of CO2 concentration, pH, and other environmental conditions on the gene regulation and ability of microalgae to synthesize lipids, (iii) investigate process conditions that select for lipid producing microalgae stains in reactors using unsterile feed solutions, and (iv) integrate the experimental work with an evaluation of the environmental and economic impacts of producing biofuels from microalgae. Intellectual Merit: The potential sustainability of microalgae fuel production, coupled with the limited knowledge of how to design and operate efficient, robust CO2 uptake and lipid synthesis systems, provide a strong rationale for investigating microalgae genetics and microbial ecology. The major outcome of this research is fundamental and applied information that directs the design, stable operation, and sustainability of microalgae-based biofuel reactors. Beyond these tangible outcomes, the proposed work is designed to make fundamental contributions toward this developing industry. These include producing gene sequence information and bioinformatics tools to enable further gene expression or genetic engineering research, providing a basis to understand how algal populations evolve under realistic microalgae biofuel reactor conditions, and ensuring the sustainability of the process by incorporating economic issues into microalgae biofuel technology development. Broader Impacts: The project promotes teaching and training through involvement of graduate and undergraduate students in research. Students from a broad cross section of disciplines will become involved in a multi-year project to design, operate, and test a variety of research hypotheses on two continuously operated, unsterile microalgae reactors. In addition to providing long term information to inform the research section of this proposed work, the project will span six different courses and is expected to produce a campus-wide opportunity for student involvement in alternative biofuel development, regardless of the student's course of study.