title: GPCR-Based Chemical Biosensors for Medium-Chain Fatty Acids.
abstract: A key limitation to engineering microbes for chemical production is a reliance on low-throughput chromatography-based screens for chemical detection. While colorimetric chemicals are amenable to high-throughput screens, many value-added chemicals are not colorimetric and require sensors for high-throughput screening. Here, we use G-protein coupled receptors (GPCRs) known to bind medium-chain fatty acids in mammalian cells to rapidly construct chemical sensors in yeast. Medium-chain fatty acids are immediate precursors to the advanced biofuel fatty acid methyl esters, which can serve as a "drop-in" replacement for D2 diesel. One of the sensors detects even-chain C8-C12 fatty acids with a 13- to 17-fold increase in signal after activation, with linear ranges up to 250 μM. Introduction of a synthetic response unit alters both dynamic and linear range, improving the sensor response to decanoic acid to a 30-fold increase in signal after activation, with a linear range up to 500 μM. To our knowledge, this is the first report of a whole-cell medium-chain fatty acid biosensor, which we envision could be applied to the evolutionary engineering of fatty acid-producing microbes. Given the affinity of GPCRs for a wide range of chemicals, it should be possible to rapidly assemble new biosensors by simply swapping the GPCR sensing unit. These sensors should be amenable to a variety of applications that require different dynamic and linear ranges, by introducing different response units.
authors.affiliation: School of Chemistry and Biochemistry, Georgia Institute of Technology , Atlanta, Georgia 30332, United States.
authors.forename: Kuntal
authors.initials: K
authors.lastname: Mukherjee
authors.affiliation: School of Chemical and Biomolecular Engineering, Georgia Institute of Technology , Atlanta, Georgia 30332, United States.
authors.forename: Souryadeep
authors.initials: S
authors.lastname: Bhattacharyya
authors.affiliation: School of Chemistry and Biochemistry, Georgia Institute of Technology , Atlanta, Georgia 30332, United States.|School of Chemical and Biomolecular Engineering, Georgia Institute of Technology , Atlanta, Georgia 30332, United States.
authors.forename: Pamela
authors.initials: P
authors.lastname: Peralta-Yahya
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D050556:Fatty Acid-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D005227:Fatty Acids / Q000032:analysis* / Q000378:metabolism; D043562:Receptors, G-Protein-Coupled / Q000235:genetics / Q000378:metabolism*; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*
chemical_list: D050556:Fatty Acid-Binding Proteins; D005227:Fatty Acids; D043562:Receptors, G-Protein-Coupled; D011994:Recombinant Proteins
keywords: GPCR; biofuels; chemical biosensors; yeast