Escherichia coli allows efficient modular incorporation of newly isolated quinomycin biosynthetic enzyme into echinomycin biosynthetic pathway for rational design and synthesis of potent antibiotic unnatural natural product

J Am Chem Soc. 2009 Jul 8;131(26):9347-53. doi: 10.1021/ja902261a.

Abstract

Natural products display impressive activities against a wide range of targets, including viruses, microbes, and tumors. However, their clinical use is hampered frequently by their scarcity and undesirable toxicity. Not only can engineering Escherichia coli for plasmid-based pharmacophore biosynthesis offer alternative means of simple and easily scalable production of valuable yet hard-to-obtain compounds, but also carries a potential for providing a straightforward and efficient means of preparing natural product analogs. The quinomycin family of nonribosomal peptides, including echinomycin, triostin A, and SW-163s, are important secondary metabolites imparting antibiotic antitumor activity via DNA bisintercalation. Previously we have shown the production of echinomycin and triostin A in E. coli using our convenient and modular plasmid system to introduce these heterologous biosynthetic pathways into E. coli. However, we have yet to develop a novel biosynthetic pathway capable of producing bioactive unnatural natural products in E. coli. Here we report an identification of a new gene cluster responsible for the biosynthesis of SW-163s that involves previously unknown biosynthesis of (+)-(1S, 2S)-norcoronamic acid and generation of aliphatic side chains of various sizes via iterative methylation of an unactivated carbon center. Substituting an echinomycin biosynthetic gene with a gene from the newly identified SW-163 biosynthetic gene cluster, we were able to rationally re-engineer the plasmid-based echinomycin biosynthetic pathway for the production of a novel bioactive compound in E. coli.

Publication types

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

MeSH terms

  • Anti-Bacterial Agents / biosynthesis*
  • Anti-Bacterial Agents / chemistry
  • Anti-Bacterial Agents / pharmacology
  • Bacillus subtilis / drug effects
  • Biosynthetic Pathways
  • Echinomycin / analogs & derivatives
  • Echinomycin / biosynthesis*
  • Echinomycin / pharmacology
  • Escherichia coli / enzymology*
  • Escherichia coli / genetics*
  • Escherichia coli Proteins / genetics
  • Escherichia coli Proteins / metabolism*
  • Genes, Bacterial
  • Multigene Family
  • Streptomyces / genetics

Substances

  • Anti-Bacterial Agents
  • Escherichia coli Proteins
  • Echinomycin