Functional genomics analysis of free fatty acid production under continuous phosphate limiting conditions

  • J. Tyler Youngquist
  • Travis C. Korosh
  • Brian F. Pfleger
Applied Genomics & Systems Biotechnology - Review


Free fatty acids (FFA) are an attractive platform chemical that serves as a functional intermediate in metabolic pathways for producing oleochemicals. Many groups have established strains of Escherichia coli capable of producing various chain-length mixtures of FFA by heterologous expression of acyl-ACP thioesterases. For example, high levels of dodecanoic acid are produced by an E. coli strain expressing the Umbellularia californica FatB2 thioesterase, BTE. Prior studies achieved high dodecanoic acid yields and productivities under phosphate-limiting media conditions. In an effort to understand the metabolic and physiological changes that led to increased FFA production, the transcriptome of this strain was assessed as a function of nutrient limitation and growth rate. FFA generation under phosphate limitation led to consistent changes in transporter expression, osmoregulation, and central metabolism. Guided by these results, targeted knockouts led to a further ~11 % in yield in FFA.


Free fatty acid Microarray Escherichiacoli Phosphate limitation Functional genomics Thioesterase 



This work was funded by the DOE Great Lakes Bioenergy Research Center (GLBRC DOE Office of Science BER DE-FC02-07ER64494) and the National Science Foundation (CBET-1149678). TCK is the recipient of a Biotechnology Training Fellowship through the National Institutes of Health (NIGMS-5 T32 GM08349).

Supplementary material

10295_2016_1846_MOESM1_ESM.xlsx (2.3 mb)
Supplementary material 1 (XLSX 2397 kb)


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Copyright information

© Society for Industrial Microbiology and Biotechnology 2016

Authors and Affiliations

  1. 1.Department of Chemical and Biological EngineeringUniversity of Wisconsin-MadisonMadisonUSA
  2. 2.Microbiology Doctoral Training Program, University of Wisconsin-MadisonMadisonUSA
  3. 3.Graduate Program in Environmental Chemistry and TechnologyUniversity of Wisconsin-MadisonMadisonUSA

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