Purification, characterization, and inhibition of peptide deformylase from Escherichia coli

Biochemistry. 1997 Nov 11;36(45):13910-8. doi: 10.1021/bi971155v.

Abstract

Peptide deformylase (EC 3.5.1.31) catalyzes the removal of a formyl group from the N-termini of nascent ribosome-synthesized polypeptides, an obligatory step during protein maturation in eubacteria. Since its discovery in crude Escherichia coli extracts 3 decades ago, the deformylase has resisted all attempts of purification or characterization due to its extraordinary lability. By placing the coding sequence (def gene) of Escherichia coli deformylase behind a bacteriophage T7 promoter, we have, however, been able to overexpress this deformylase in Escherichia coli. Overproduction has allowed the purification of > 50 mg of deformylase enzyme from each liter of cell culture. Purified deformylase is highly active toward N-formylated peptide substrates. A new, sensitive assay for the deformylase has been developed by measuring the amount of released formate using a formate dehydrogenase. This has allowed for the assessment of the catalytic properties of peptide deformylase using a series of synthetic N-formylated peptides as substrates. The deformylase exhibits strong preference for an L-methionine or the isosteric norleucine at the N-terminus of a substrate and has broad specificity for the rest of the residues. Small divalent metal chelators strongly inhibit the E. coli deformylase. In particular, certain 1,2- and 1,3-dithiol compounds act as potent, time-dependent inhibitors of the peptide deformylase.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amidohydrolases*
  • Amino Acid Sequence
  • Aminopeptidases / antagonists & inhibitors*
  • Aminopeptidases / biosynthesis
  • Aminopeptidases / chemistry
  • Aminopeptidases / isolation & purification*
  • Cations, Divalent
  • Chelating Agents / pharmacology
  • Enzyme Stability
  • Escherichia coli / enzymology*
  • Escherichia coli / genetics
  • Hydrogen-Ion Concentration
  • Kinetics
  • Metalloproteins / antagonists & inhibitors*
  • Metalloproteins / chemistry
  • Metalloproteins / isolation & purification*
  • Recombinant Proteins / biosynthesis
  • Recombinant Proteins / isolation & purification
  • Substrate Specificity
  • Sulfhydryl Compounds / pharmacology

Substances

  • Cations, Divalent
  • Chelating Agents
  • Metalloproteins
  • Recombinant Proteins
  • Sulfhydryl Compounds
  • Aminopeptidases
  • Amidohydrolases
  • peptide deformylase