Acyldepsipeptide Antibiotics and a Bioactive Fragment Thereof Differentially Perturb Mycobacterium tuberculosis ClpXP1P2 Activity in Vitro

ACS Chem Biol. 2023 Apr 21;18(4):724-733. doi: 10.1021/acschembio.9b00454. Epub 2022 Oct 14.

Abstract

Proteolytic complexes in Mycobacterium tuberculosis (Mtb), the deadliest bacterial pathogen, are major foci in tuberculosis drug development programs. The Clp proteases, which are essential for Mtb viability, are high-priority targets. These proteases function through the collaboration of ClpP1P2, a barrel-shaped heteromeric peptidase, with associated ATP-dependent chaperones like ClpX and ClpC1 that recognize and unfold specific substrates in an ATP-dependent fashion. The critical interaction of the peptidase and its unfoldase partners is blocked by the competitive binding of acyldepsipeptide antibiotics (ADEPs) to the interfaces of the ClpP2 subunits. The resulting inhibition of Clp protease activity is lethal to Mtb. Here, we report the surprising discovery that a fragment of the ADEPs retains anti-Mtb activity yet stimulates rather than inhibits the ClpXP1P2-catalyzed degradation of proteins. Our data further suggest that the fragment stabilizes the ClpXP1P2 complex and binds ClpP1P2 in a fashion distinct from that of the intact ADEPs. A structure-activity relationship study of the bioactive fragment defines the pharmacophore and points the way toward the development of new drug leads for the treatment of tuberculosis.

Publication types

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

MeSH terms

  • Adenosine Triphosphate / metabolism
  • Anti-Bacterial Agents* / metabolism
  • Anti-Bacterial Agents* / pharmacology
  • Bacterial Proteins / metabolism
  • Endopeptidase Clp / chemistry
  • Humans
  • Molecular Chaperones / metabolism
  • Mycobacterium tuberculosis* / drug effects
  • Mycobacterium tuberculosis* / metabolism
  • Peptide Hydrolases / drug effects
  • Peptide Hydrolases / metabolism
  • Tuberculosis* / drug therapy

Substances

  • acyldepsipeptides
  • Adenosine Triphosphate
  • Anti-Bacterial Agents
  • Bacterial Proteins
  • Endopeptidase Clp
  • Molecular Chaperones
  • Peptide Hydrolases
  • clpP2 protein, Mycobacterium tuberculosis
  • clpP1 protein, Mycobacterium tuberculosis