title: Surface Enhanced Raman Scattering for Quantification of p-Coumaric Acid Produced by Escherichia coli.
abstract: The number of newly developed genetic variants of microbial cell factories for production of biochemicals has been rapidly growing in recent years, leading to an increased need for new screening techniques. We developed a method based on surface-enhanced Raman scattering (SERS) coupled with liquid-liquid extraction (LLE) for quantification of p-coumaric acid (pHCA) in the supernatant of genetically engineered Escherichia coli (E. coli) cultures. pHCA was measured in a dynamic range from 1 μM up to 50 μM on highly uniform SERS substrates based on leaning gold-capped nanopillars, which showed an in-wafer signal variation of only 11.7%. LLE using dichloromethane as organic phase was combined with the detection in order to increase selectivity and sensitivity by decreasing the effect of interfering compounds from the analytes of interest. The difference in pHCA production yield between three genetically engineered E. coli strains was successfully evaluated using SERS and confirmed with high-performance liquid chromatography. As this novel approach has potential to be automated and parallelized, it can be considered for high-throughput screening in metabolic engineering.
authors.affiliation: Department of Micro- and Nanotechnology, Technical University of Denmark , 2800 Kongens Lyngby, Denmark.
authors.forename: Lidia
authors.identifier: 0000-0002-3299-8608
authors.initials: L
authors.lastname: Morelli
authors.affiliation: Department of Micro- and Nanotechnology, Technical University of Denmark , 2800 Kongens Lyngby, Denmark.
authors.forename: Kinga
authors.initials: K
authors.lastname: Zór
authors.affiliation: The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark , 2800 Kongens Lyngby, Denmark.
authors.forename: Christian Bille
authors.initials: CB
authors.lastname: Jendresen
authors.affiliation: Department of Micro- and Nanotechnology, Technical University of Denmark , 2800 Kongens Lyngby, Denmark.
authors.forename: Tomas
authors.initials: T
authors.lastname: Rindzevicius
authors.affiliation: Department of Micro- and Nanotechnology, Technical University of Denmark , 2800 Kongens Lyngby, Denmark.
authors.forename: Michael Stenbæk
authors.initials: MS
authors.lastname: Schmidt
authors.affiliation: The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark , 2800 Kongens Lyngby, Denmark.
authors.forename: Alex Toftgaard
authors.initials: AT
authors.lastname: Nielsen
authors.affiliation: Department of Micro- and Nanotechnology, Technical University of Denmark , 2800 Kongens Lyngby, Denmark.
authors.forename: Anja
authors.initials: A
authors.lastname: Boisen
mesh_terms: D003373:Coumaric Acids; D004926:Escherichia coli / Q000737:chemistry / Q000378:metabolism*; D006046:Gold / Q000737:chemistry; D053768:Metal Nanoparticles / Q000737:chemistry; D015394:Molecular Structure; D011422:Propionates / Q000032:analysis* / Q000378:metabolism; D013059:Spectrum Analysis, Raman; D013499:Surface Properties
chemical_list: D003373:Coumaric Acids; D011422:Propionates; D006046:Gold; C495469:p-coumaric acid