New Approach Reduces Cost, Improves Yield of Industrial Chemicals

Achievement date: 
2014
Outcome/accomplishment: 

We are moving closer to greater industrial use of synthetic biology, thanks to research sponsored by the Synthetic Biology Engineering Research Center (SynBERC), an NSF-funded center headquartered at the University of California at Berkeley. SynBERC researchers found a way to harness an organism's natural response machinery to regulate chemical processes, reducing cost and improving production of desired chemicals.

Impact/benefits: 

From life-saving drugs to sustainable, green biofuels, the metabolic engineering of microbes for the production of valuable chemicals continues to grow in importance. However, the most productive “microbial hosts” now in use have been engineered in such a way that there is little or no native regula­tion within the chemical process, which can result in toxic impact to the host—and limited production of the target chemical. Harnessing an organism's natural response machinery to regulate heterologous pathways in an inducer-free manner is a simple yet powerful solution to what has been a significant roadblock to industrial application of synthetic biology.

Explanation/Background: 

Just as a factory can generate pollution and a health risk, microbes engineered to synthesize a useful product, such as a drug or biofuel, can create toxic intermediates on the way to the final product that can limit production. SynBERC researchers found a novel solution to this problem: harnessing the natural stress mechanisms of E. coli.

They screened the genome of E. coli and identified promoters that responded to toxic intermediates. Using such promoters to regulate pathway expression in response to the intermediates creates a link between the cell's metabolic state and the expression of the metabolic pathway. This approach increased the concentration of an organic chemical by twofold over that achieved by other methods.