Artificial covalent linkage of bacterial acyl carrier proteins for fatty acid production

Sci Rep. 2019 Nov 5;9(1):16011. doi: 10.1038/s41598-019-52344-w.


Acyl carrier proteins (ACPs) are essential to the production of fatty acids. In some species of marine bacteria, ACPs are arranged into tandem repeats joined by peptide linkers, an arrangement that results in high fatty acid yields. By contrast, Escherichia coli, a relatively low producer of fatty acids, uses a single-domain ACP. In this work, we have engineered the native E. coli ACP into tandem di- and tri-domain constructs joined by a naturally occurring peptide linker from the PUFA synthase of Photobacterium profundum. The size of these tandem fused ACPs was determined by size exclusion chromatography to be higher (21 kDa, 36 kDa and 141 kDa) than expected based on the amino acid sequence (12 kDa, 24 kDa and 37 kDa, respectively) suggesting the formation of a flexible extended conformation. Structural studies using small-angle X-ray scattering (SAXS), confirmed this conformational flexibility. The thermal stability for the di- and tri-domain constructs was similar to that of the unfused ACP, indicating a lack of interaction between domains. Lastly, E. coli cultures harboring tandem ACPs produced up to 1.6 times more fatty acids than wild-type ACP, demonstrating the viability of ACP fusion as a method to enhance fatty acid yield in bacteria.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Acyl Carrier Protein / chemistry
  • Acyl Carrier Protein / genetics
  • Acyl Carrier Protein / metabolism*
  • Amino Acid Sequence
  • Bacterial Proteins / chemistry
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism*
  • Escherichia coli / metabolism
  • Fatty Acids / analysis
  • Fatty Acids / metabolism*
  • Gas Chromatography-Mass Spectrometry
  • Photobacterium / metabolism*
  • Protein Conformation
  • Protein Stability
  • Recombinant Proteins / biosynthesis
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / isolation & purification
  • Scattering, Small Angle
  • Temperature
  • X-Ray Diffraction


  • Acyl Carrier Protein
  • Bacterial Proteins
  • Fatty Acids
  • Recombinant Proteins

Supplementary concepts

  • Photobacterium profundum