Engineered short branched-chain acyl-CoA synthesis in E. coli and acylation of chloramphenicol to branched-chain derivatives

Appl Microbiol Biotechnol. 2013 Dec;97(24):10339-48. doi: 10.1007/s00253-013-5262-6. Epub 2013 Oct 8.

Abstract

Short branched-chain acyl-CoAs are important building blocks for a wide variety of pharmaceutically valuable natural products. Escherichia coli has been used as a heterologous host for the production of a variety of natural compounds for many years. In the current study, we engineered synthesis of isobutyryl-CoA and isovaleryl-CoA from glucose in E. coli by integration of the branched-chain α-keto acid dehydrogenase complex from Streptomyces avermitilis. In the presence of the chloramphenicol acetyltransferase (cat) gene, chloramphenicol was converted to both chloramphenicol-3-isobutyrate and chloramphenicol-3-isovalerate by the recombinant E. coli strains, which suggested successful synthesis of isobutyryl-CoA and isovaleryl-CoA. Furthermore, we improved the α-keto acid precursor supply by overexpressing the alsS gene from Bacillus subtilis and the ilvC and ilvD genes from E. coli and thus enhanced the synthesis of short branched-chain acyl-CoAs. By feeding 25 mg/L chloramphenicol, 2.96 ± 0.06 mg/L chloramphenicol-3-isobutyrate and 3.94 ± 0.06 mg/L chloramphenicol-3-isovalerate were generated by the engineered E. coli strain, which indicated efficient biosynthesis of short branched-chain acyl-CoAs. HPLC analysis showed that the most efficient E. coli strain produced 80.77 ± 3.83 nmol/g wet weight isovaleryl-CoA. To our knowledge, this is the first report of production of short branched-chain acyl-CoAs in E. coli and opens a way to biosynthesize various valuable natural compounds based on these special building blocks from renewable carbon sources.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acyl Coenzyme A / metabolism*
  • Acylation
  • Anti-Bacterial Agents / metabolism*
  • Bacillus subtilis / enzymology
  • Bacillus subtilis / genetics
  • Biotransformation
  • Chloramphenicol / metabolism*
  • Chromatography, High Pressure Liquid
  • Escherichia coli / genetics
  • Escherichia coli / metabolism*
  • Metabolic Engineering*
  • Metabolic Networks and Pathways / genetics*
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism
  • Streptomyces / enzymology
  • Streptomyces / genetics

Substances

  • Acyl Coenzyme A
  • Anti-Bacterial Agents
  • Recombinant Proteins
  • Chloramphenicol