Metabolic engineering: enabling technology for biofuels production

Focus Article

Mitchell Tai, Gregory N. Stephanopoulos

Published Online: Jun 05 2012

DOI: 10.1002/wene.5

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Abstract The biofuels industry is rapidly growing with the goal of providing a sustainable fuel alternative to petroleum products. However, two challenges persist in limiting current biofuels technologies as a viable alternative: (1) the cost of feedstock and (2) the quality of the fuel. Metabolic engineering shows the potential to overcome these two challenges, enabling the bioconversion of cheaper feedstocks into improved fuels in a sustainable and environmentally friendly manner. Metabolic engineering is the systematic attempt to understand, design, and engineer cellular metabolic networks using a wide range of interdisciplinary tools and strategies. It is rapidly emerging as the enabling technology behind the development of the next generation of biofuels. Several examples of current research demonstrate how metabolic engineering has begun to contribute both novel and creative solutions toward bringing promising biofuel technologies to fruition: production of higher chain alcohols, fermentation of lignocellulosic material, and production of fatty acid derivatives. © 2012 John Wiley & Sons, Ltd. This article is categorized under: Bioenergy > Science and Materials Energy and Development > Science and Materials

Strategies of metabolic engineering revolve around the understanding, design, and engineering of metabolic networks and pathways to produce desired molecular products from biological platforms. These strategies employ techniques and technologies from a range of disciplines, from omics technology to synthetic biology.

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Metabolic network of biofuel production pathways and intermediates for the conversion of feedstocks to fuels (bold text): current biofuels (orange), higher chain alcohols (blue), lignocellulosic fermentation (green), and fatty acid derivatives (purple). Engineering the desired biofuel pathway requires maximizing flux through the relevant nodes while minimizing metabolite flux to competing branches. This can involve tuning expression of intermediate reaction steps, deletion of competing pathways, or manipulation of distal enzymatic or regulatory targets.

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