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Fragments of the bacterial toxin microcin B17 as gyrase poisons

Frédéric Collin1, Robert E Thompson, Katrina A Jolliffe

  • 1Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich, United Kingdom.

Plos One
|April 18, 2013
PubMed

Insights

Microcin B17 (MccB17) stabilizes bacterial DNA gyrase, similar to fluoroquinolone antibiotics. Researchers identified MccB17 fragments that retain this DNA cleavage complex stabilization ability for new antibiotic development.

Area of Science:

  • Microbiology
  • Drug Discovery
  • Structural Biology

Background:

  • Fluoroquinolones are crucial antibiotics targeting bacterial DNA gyrase.
  • Bacterial resistance to antibiotics necessitates novel therapeutic strategies.
  • Microcin B17 (MccB17) shares a similar mechanism of action with fluoroquinolones but is not therapeutically viable.

Purpose of the Study:

  • To investigate the structural elements of MccB17 responsible for its antibacterial activity.
  • To identify MccB17 fragments capable of stabilizing the DNA gyrase-DNA cleavage complex.
  • To explore MccB17 as a potential scaffold for developing new antibacterial agents.

Main Methods:

  • Structural analysis of Microcin B17.
  • Biochemical assays to assess cleavage complex stabilization.
  • Identification and characterization of active MccB17 fragments.

Main Results:

  • Specific structural features of MccB17 were identified as critical for its activity.
  • Certain fragments of MccB17 were found to effectively stabilize the gyrase-DNA cleavage complex.
  • These fragments demonstrate potential as starting points for novel antibiotic design.

Conclusions:

  • MccB17's mechanism provides insights into DNA gyrase inhibition.
  • Fragment-based studies of MccB17 can lead to the development of new antibacterial drugs.
  • This research contributes to combating antibiotic resistance by exploring alternative molecular scaffolds.

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