Bioinformatic and Functional Evaluation of Actinobacterial Piperazate Metabolism

ACS Chem Biol. 2019 Apr 19;14(4):696-703. doi: 10.1021/acschembio.8b01086. Epub 2019 Apr 9.

Abstract

Piperazate (Piz) is a nonproteinogenic amino acid noted for its unusual N-N bond motif. Piz is a proline mimic that imparts conformational rigidity to peptides. Consequently, piperazyl molecules are often bioactive and desirable for therapeutic exploration. The in vitro characterization of Kutzneria enzymes KtzI and KtzT recently led to a biosynthetic pathway for Piz. However, Piz anabolism in vivo has remained completely uncharacterized. Herein, we describe the systematic interrogation of actinobacterial Piz metabolism using a combination of bioinformatics, genetics, and select biochemistry. Following studies in Streptomyces flaveolus, Streptomyces lividans, and several environmental Streptomyces isolates, our data suggest that KtzI-type enzymes are conditionally dispensable for Piz production. We also demonstrate the feasibility of Piz monomer production using engineered actinobacteria for the first time. Finally, we show that some actinobacteria employ fused KtzI-KtzT chimeric enzymes to produce Piz. Our findings have implications for future piperazyl drug discovery, pathway engineering, and fine chemical bioproduction.

Publication types

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

MeSH terms

  • Amino Acids / chemistry*
  • Amino Acids / metabolism
  • Bacterial Proteins / chemistry
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism
  • Computational Biology
  • Kinetics
  • Mutant Chimeric Proteins / chemistry
  • Mutant Chimeric Proteins / genetics
  • Mutant Chimeric Proteins / metabolism
  • Mutation
  • Pyridazines / chemistry*
  • Pyridazines / metabolism
  • Streptomyces / genetics
  • Streptomyces / isolation & purification
  • Streptomyces / metabolism

Substances

  • Amino Acids
  • Bacterial Proteins
  • Mutant Chimeric Proteins
  • Pyridazines
  • piperazic acid